Prostaglandin E2 production by the membrane surrounding loose and fixated cemented tibial hemiarthroplasties in the rabbit knee. Sixteen mature New Zealand female rabbits had cemented, tibial hemiarthroplasty of the right knee (correction of hip) using a stemmed, fluted, titanium-alloyed, condylar type prosthesis. In the fixated prosthetic group (eight rabbits), a 1.5-cm3 doughy bolus of polymethylmethacrylate (PMMA) was used to cement the prosthesis firmly. In the loose group (eight rabbits), the cement was allowed to cure ex vivo on the implant; the prosthesis was then implanted and rotated to ensure that it was loose fitting. Roentgenograms performed postoperatively and at three months were graded for new lucent lines. The implant area was harvested aseptically and cultured during a three-day period, and the cumulative collection of tissue culture supernatants was assayed for prostaglandin E2 (PGE2). The mean cumulative grading of new lucent lines was 0.4 +/- 0.2 (mean +/- SEM) for the fixated prosthetic group and 2.3 +/- 0.5 for the loose prosthetic group. Specimens from the nonloose group produced 8.85 +/- 1.44 ng of PGE2 on the right prosthetic side, and 17.29 +/- 3.72 ng of PGE2 on the left, nonimplanted side. Specimens from the loose prosthesis group produced 52.35 +/- 16.28 ng of PGE2 on the right prosthetic side and 17.29 +/- 3.72 ng of PGE2 on the left, nonimplanted side. Increased PGE2 production relative to fixated prostheses was noted in the membranes surrounding loose prostheses. The left, nonimplanted sides were not statistically different. Roentgenographic and biochemical evidence indicates that a cemented tibial hemiarthroplasty implanted in the rabbit knee can provide a short-term model of arthroplasty loosening.


Effects of cyclosporin A on experimental new bone formation in rats. The effects of the immunosuppressive drug cyclosporin A (CsA) on bone induction by demineralized allogeneic (rat) bone matrix (DABM) and demineralized xenogeneic (rabbit) bone matrix (DXBM) were studied. Growing rats were implanted with three samples each of DABM and DXBM. Groups of eight rats were treated with 0.5 or 2 mg CsA/kg body weight for four weeks and compared with a placebo group. Cyclosporin A treatment enhanced bone induction in DABM implants by 40 to 50% at four weeks, whereas there was no difference from the control group at eight weeks. Demineralized xenogeneic bone matrix induced virtually no bone in control rats at four weeks, whereas the net bone formation increased four to five times in both groups of CsA-treated rats. At eight weeks, DXBM without CsA had induced some bone formation, and the amount was almost equal to that of DABM implants in CsA-treated groups. Also, the mineral accretion rates of DXBM were equal to DABM implants in CsA-treated rats. Cyclosporin A treatment doubled the uptake of 45Ca in the orthotopic skeleton (femora) at four weeks without affecting the mineral content, indicating an increased mineral turnover. Immunologic reactions may inhibit bone induction by DXBM, which can be counteracted by treatment with CsA.


Biomechanical comparisons of unidirectional and bidirectional Kirschner-wire insertion. Peak axial loads on entry and peak pull-out loads were measured for Kirschner-wires (K-wire) inserted into canine metacarpals. The wires were placed using a standard, unidirectional drill and using an oscillating, bidirectional drill that reversed spin direction every 120 degrees. Seven trocar-tip wires were compared with seven diamond-tip wires using each drilling method. The trocar-tip wires demonstrated equal peak axial loads on entry when drilled at comparable speeds unidirectionally and bidirectionally. Pull-out load of the trocar tip after bidirectional insertion was less than that for unidirectional insertion but was still in the clinically useful range. The diamond-tip wire exhibited higher peak axial load on entry and lower peak pull-out load when drilled bidirectionally. Bidirectional insertion of a trocar-tip K-wire offers fixation characteristics comparable with those with unidirectional insertion and will potentially reduce the risk of soft-tissue damage associated with winding-up and avulsion of vital structures on the spinning shaft of a unidirectional driver.


In vitro elution characteristics of commercially and noncommercially prepared antibiotic PMMA beads. The successful treatment of osteomyelitis with commercially prepared gentamicin-polymethylmethacrylate (PMMA) (Septopal) beads and surgical debridement has led to the use of this technique in the United States. However, commercially prepared gentamicin-PMMA beads are not currently available to orthopedic surgeons in the United States. Therefore, these surgeons commonly manufacture their own antibiotic-containing cement beads in the operating room at the time of surgery. There is little data that compare the antibiotic elution characteristics of such preparations to commercially prepared gentamicin-PMMA beads. This study compares the measured amount of antibiotic elution of either gentamicin or tobramycin from laboratory manufactured Zimmer, Simplex, or Palacos beads to commercially prepared gentamicin-PMMA (Septopal) beads. During a 30-day study period, commercially prepared gentamicin-PMMA beads eluted more total antibiotic and maintain higher concentrations than did antibiotic acrylic composites manufactured in the authors' laboratory.


Anatomic and technical considerations of pedicle screw fixation. Pedicle screw systems provide significant and, in many cases, improved and previously unattainable spinal fixation. However, pedicle screw systems represent difficult surgical techniques involving several potential problems and complications. Only by detailed knowledge of the anatomy of the spine, with a clear understanding of the pedicle screw systems implementation, can the risks of complications be minimized.


Anterior lumbar interbody fusion surgical complications. Complications of anterior lumbar fusion may be divided into several categories. The first of these is complications related to patient selection, the second is visceral complications, and the third is vascular complications. Complications of anterior lumbar fusion and complications of interbody fusion technique occur at the graft site and the donor site.


Complications of anterior intervertebral grafting. Reconstruction of the spine after anterior decompression is essential to restore stability and function. A variety of materials and methods are available to reconstitute the vertebral column. Numerous complications of anterior grafting have been identified, and include failure of the graft, graft extrusion, nonunion, and infection. The clinical severity of these complications vary. The use of spinal instrumentation has helped to address some of these problems. Although certain problems are the result of faulty decision making or technical error, others are related to the severity of the patient's disease and the limitations of grafting materials. Some complications can be avoided while others can be anticipated and perhaps corrected early.


Complications of chemonucleolysis.

Complications of chemonucleolysis. Complications in chemonucleolysis are inevitable. However, the incidence of these may be minimized with attention to detail. Proper patient selection, based on a knowledge of the natural history of lumbar disk herniation and elimination of patients with contraindications to diskolysis, will result in a higher success rate with lower incidence of complications in diskolysis. Once the proper patient has been selected, attention must be turned to technique with respect to the use of local anesthesia, appropriate patient positioning, good fluoroscopic control, and two-needle technique for appropriate needle positioning. Immunologic complications can be nearly eliminated with the use of a preoperative enzyme immunoassay test. Carefully considering all of these factors will allow chemonucleolysis to present a safe alternative to disk surgery.


Percutaneous diskectomy.

Percutaneous diskectomy. Automated percutaneous diskectomy and manual percutaneous diskectomy (PCD) have gained recent popularity as alternatives to traditional surgical diskectomy or microdiskectomy. Initial reports of morbidity seem low. The rates of infection, and neurologic and vascular complications appear comparable or less than the morbidity associated with surgical diskectomy or microdiskectomy. However, inconsistent reports of the efficacy of PCD may cause more concern about overuse than about the morbidity.


Pseudarthrosis of the spine.

Pseudarthrosis of the spine. Pseudarthrosis remains the leading cause of failed spinal fusions. The common causes of this complication are inadequate surgical technique, excessive stresses across the fusion site, insufficient internal or external stabilization, and unrecognized metabolic abnormalities. Many radiologic techniques have been used to diagnose pseudarthrosis in the spine. Nonetheless, the diagnosis of a nonunion as well as the ability to correlate the nonunion with the patient's clinical symptoms remains a challenge. In treating a symptomatic pseudarthrosis, the surgeon should first attempt to identify those factors that contributed to the development of a nonunion. The approach can then either be exploration of the fusion mass with regrafting of the pseudarthrosis or extending a fusion to locations within the abnormal segment of spinal motion.


Disk herniations associated with compression instrumentation of lumbar flexion-distraction injuries. Flexion-distraction injuries are often treated by open reduction and fusion using compression instrumentation. Three cases that were complicated by disk herniation at the injured level, with an acquired neurologic deficit, are reported. Middle-column failure through the annulus fibrosis (Gertzbein and Court-Brown Type A) appeared to be a common feature. This may be a permissive condition for this complication as compression is applied across the torn annulus. Preoperative magnetic resonance imaging and postreduction myelography may identify such herniations. Acquired neurologic deficits after reduction and instrumentation demand emergent evaluation and treatment.


Postoperative posterior spinal wound infections. The incidence of postoperative spinal infections increases with the complexity of the procedure. Diskectomy is associated with less than a 1% risk of infection; spinal fusion without instrumentation is associated with a 1%-5% risk; and fusion with instrumentation may be associated with a risk of 6% or more. Twenty-two postoperative posterior spinal infections that occurred during a three-year period were reviewed for this report. Staphylococcus aureus was the most frequent organism cultured (more than 50% of the cases). Other recurring organisms were Staphylococcus epidermis, Peptococcus, Enterobacter cloacae, and Bacteroides. Many patients had multiple organisms. Risk factors appeared to include advanced age, prolonged hospital bed rest, obesity, diabetes, immunosuppression, and infection at remote sites. Operative factors included prolonged surgery (greater than five hours), high volume of personnel moving through the operating room, and instrumentation. Postoperative contamination may occur and may be related to prolonged postoperative bed rest, skin maceration (thoracolumbosacral orthoses), and drainage tubes exiting distally from lumbar wounds (toward the rectum). Effective treatment includes early diagnosis, surgical debridement and irrigation, and parenteral antibiotics. Superficial infections were treated successfully with wound closure over outflow tubes, and deep infections with inflow-outflow systems. Maintaining the instrumentation in place was possible in most cases. Parenteral antibiotics were maintained for six weeks in every case.


[Adult GM1 gangliosidosis--biochemical studies--1]. To address the pathogenesis of GM1 gangliosidosis, especially adult form, intracellular signal transduction pathway of EGF in skin fibroblasts from patients with this disorder was examined. For this purpose, skin fibroblasts from 2 different patients with adult form of the disorder and from 4 different normal controls were used. The results showed that 1) EGF-receptor autophosphorylation was diminished in skin fibroblasts from patients with altered time course of phosphorylation-dephosphorylation reaction. 2) The amount of EGF-receptor protein was decreased in cells from patients compared with that of controls. 3) 125I-EGF binding + internalization studies revealed decreased rate of EGF binding and internalization in patient cells. 4) Ribosomal S6 protein phosphorylation was strongly enhanced in naive cells from patients, but the reactivity to EGF was diminished compared with control cells. These data strongly suggest that patient fibroblasts have abnormalities in the intracellular signal transduction pathway of EGF. This paper is considered to be the first report demonstrating abnormalities in EGF-signal transducing system in human disorders.


[The corticospinal tract of amyotrophic lateral sclerosis--a morphometric analysis of the myelinated fibers]. The myelinated fibers in the lateral corticospinal tract at the C6, T7, L4 levels in amyotrophic lateral sclerosis (ALS) and control cases were morphometrically examined. ALS cases consisted of 6 males and 2 females with ages ranging between 48 and 85 years, and were all the common or bulbar form in clinical manifestation. As for controls, 10 cases who died of non-neurological diseases, with age ranging 36 to 90 years were served. The population and the diameter profile of the myelinated fibers in the corticospinal tract of the C6, T7, L4 levels were measured by the method previously described and expressed as number per mm2. In control subjects, fiber-size histograms of myelinated fibers showed a bimodal pattern with a sharp peak of small fibers (less than 7.28 microns) and a broad peak of large fibers (greater than or equal to 7.28 microns) in all the spinal levels. In ALS cases, large myelinated fibers were predominantly diminished in number, a small myelinated fibers were also decreased in some cases. The degree of fiber loss was extremely variable among cases; well populated in large fibers in some cases. As for the rostral caudal distribution of myelinated fiber loss, a caudally-accentuated fiber loss particularly in large fiber was seen in some of the cases. The topographical distribution of fiber loss in the horizontal plane of the corticospinal tract in ALS did not show a distinctive pattern.


[The effect of anticholinergic drugs on 123I-IMP SPECT in Parkinson's disease]. Several reports have suggested that anticholinergics have some associations with mental deterioration in Parkinson's disease (PD). We investigated the effect of anticholinergics on regional cerebral uptake of tracer in PD patients using N-isopropyl p-[I-123] iodoamphetamine SPECT. Sixteen pairs of region of interest (ROI) were located in the cortex, a pair in the basal ganglia, thalamus, and cerebellum. The size of each ROI was about 16 mm x 16 mm. Regional cerebral uptake ratio (rCUR) was calculated by the next equation: rCUR = (total count in an ORI)/(mean of total count in the cerebellar ROIs). The comparison consisted of two parts; (1) 7 PD patients (age 59-76 (65.4 +/- 6.7 mean +/- S.D.)) who had been on chronic anticholinergic therapy underwent SPECT and Wechsler Adult Intelligence Scale (WAIS) twice, for the first time when they were on anticholinergics and second a month after discontinuation of anticholinergics. All but two patients performed significantly better on WAIS after discontinuation than when they were on anticholinergics. The improvement was about 10 points in total IQ. (2) 11 PD patients (age 52-79 (64.5 +/- 8.6 mean +/- S.D.)) on chronic anticholinergic therapy including all but two patients mentioned above (group A) and 25 PD patients (age 52-88 (66.7 +/- 9.8 mean +/- S.D.)) not receiving anticholinergics (group B) also underwent SEPCT. In the comparison (1), at all but two ROIs was the mean rCUR higher after discontinuation than when they were on anticholinergics and the difference was significant at 10 ROIs out of 32 ROIs in the cortex.(ABSTRACT TRUNCATED AT 250 WORDS)


[Transcranial magnetic stimulation of the facial nerve]. It was the object of the present study to determine whether transcranial facial nerve stimulation using a magnetic coil can be clinically applicable, and to find the site where the facial nerve is best stimulated. A magnetic coil was placed over the parieto-occipital skull of the subjects for stimulation, and the facial nerve was electrically stimulated in its intracranial and peripheral courses. Then an electromyogram was recorded from the nasalis muscle of the face on the stimulated side. In 9 healthy volunteers, 18 facial nerves received magnetic and electric stimuli in the peripheral region, and the actual site of stimulation was estimated from the conduction velocity of the nerve. The conduction velocity was 56.6 +/- 4.8 m/s, and the latency between CMAPs for electric at the magnetic stimuli to the posterior tragus was 1.23 +/- 0.21 ms. Therefore, the position stimulated by magnetic coil was estimated to be 70.0 +/- 11.4 mm central to the posterior tragus, i.e., near the root exit zone. In two patients undergoing surgery in the cerebellopontine angle, transcranial magnetic stimulation and electrical stimulation of the intracranial facial nerve were compared intraoperatively. The CMAP produced by transcranial magnetic stimulation coincided closely with that produced by direct electrical stimulation of the root exit zone. Thus, the facial nerve was stimulated at the root exit zone, and this method could be expected to be useful for evaluation of disorders of the intracranial facial nerve.


[Cerebrospinal fluid levels of 28 kDa calcium-binding protein in patients with neurological diseases]. Vitamin D-dependent calcium-binding protein (Calbindin-D: CaBP) (MW 28 kDa) is present in high concentrations in the central nervous system (CNS), especially in the cerebellum. In the cerebellum, CaBP is localized in Purkinje cells. By using an enzyme immunoassay method, we measured the cerebrospinal fluid (CSF) levels of CaBP in 96 neurological patients and 24 control subjects, and evaluated the clinical usefulness of determining CaBP, especially in the diagnosis of cerebellar damage. CSF CaBP levels were strikingly elevated in patients with cerebellar lesions, including primary spinocerebellar degeneration (SCD), subacute cerebellar degeneration with lung cancer, Wernicke-Korsakoff syndrome, as well as in patients with cerebrovascular disease (CVD) without involvement of the cerebellum. In these 2 groups, neuron-specific enolase (NSE) levels were determined. The ratio of CaBP to NSE (CaBP/NSE) in patients with cerebellar lesions was higher than that in CVD, reflecting differences in lesions between these 2 groups. In the SCD group, multiple system atrophy (MSA) showed higher CaBP levels than the other types of SCD. Probably it reflects remarkable damage of the Purkinje cells in MSA. In MSA, the CaBP levels decreased with the duration of illness. In myelopathy, neuropathy, meningitis, multiple sclerosis, and other degenerative diseases, the increase of CaBP was not remarkable. Our results suggested that CSF CaBP is considered to be a marker of cerebellar damage.


[A multivariate analysis of prognostic factors of spinocerebellar degenerations]. To clarify the factors relating to the prognosis of spinocerebellar degenerations (SCD), we performed a follow-up study on the survival of patients with Friedreich disease, familial spastic paraparasis, sporadic olivopontocerebellar atrophy (OPCA), hereditary OPCA of Menzel type, sporadic late cortical cerebellar atrophy (LCCA), cerebellar atrophy of Holmes type, Shy-Drager syndrome, striatonigral degeneration, dentatorubropallidoluysian atrophy, or Joseph disease. One hundred and forty-eight patients admitted to the Nagoya University Hospital during the period of 1976 to 1990 were dealt with. They had been followed-up for 15 years at longest through the medical records, or through the direct informations from the patients or their family members or both. In order to find factors influencing the survival of the patients, Kaplan-Meier method was used as the 1st step to construct the survival curve for each factor. These were calculated by generalized Wilcoxon test. Employing Cox's proportional hazard model, a multivariate analysis was then performed based on the factors which were shown significant in the 1st step. The multivariate analysis showed that the following four factors are related to the prognosis of SCD patients, i.e., lack of hereditary trait, existence of orthostatic hypotension, lack of walking disorder at onset, and lack of nystagmus on admission. Of these factors, the lack of hereditary trait had the most intimate relation to their poor prognosis. Therefore, these four factors are statistically informative to predict prognosis of each patient with SCD.


[A case of SSPE presenting visual disturbance and serial MRI study]. A case of subacute sclerosing panencephalitis (SSPE) was reported. The patient was a 16-year-old boy and he initially developed visual disturbance. His neurologic symptoms were myoclonus, dementia, and visual disturbance which was rare as an initial symptom in SSPE. Fundoscopy revealed bilateral pole chorioretinitis and macular degeneration. Serial MRI study demonstrated the lesions in the brain and right eye ball. The distribution varied as time went on. T2-weighted MR images showed the lesions more clearly than T1-weighted MR images. In this case dementia was marked but the lesions in the cerebrum on the MR images were considerably smaller than expected. Although MR image is useful to show the lesions, the discrepancy between clinical signs and MR images may be present in the early stage in SSPE.


[Two familial cases with exertion-induced heat stroke--relationship to malignant hyperthermia]. Two patients in a family of exertion-induced heat stroke were reported. Case 1: A 23-year-old male, paternal cousin of case 2, was admitted to our hospital because of loss of consciousness during running under a burning sun. On physical and neurological examinations, he was deeply comatose with high fever, tachycardia, and increased deep tendon reflexes. Laboratory findings disclosed rhabdomyolysis, acute renal failure, disseminated intravascular coagulation, liver injury, and brain edema. He recovered after intensive cooling, some antibiotics, glycerol and sodium dantrolene administration. Case 2: A 19-year-old male experienced loss of consciousness and high fever during playing soccer at 15 years of age, and was admitted to a hospital. On admission, he had high fever of 38.7 degrees C, and increased serum CK level. He recovered two weeks after admission. He was readmitted to our hospital to evaluate the predisposition for malignant hyperthermia. His physical and neurological examinations showed no abnormalities. Routine laboratory findings were within normal limits. Muscle biopsy findings of cases 1 and 2 were mildly increased number of fibers with centrally placed nuclei. Caffeine test on skinned muscle fibers from the biopsies showed normal response in both type 1 and 2 fibers. The present patients were diagnosed as having exertion-induced heat stroke, but with no increased muscle fiber sensitivity to caffeine, suggesting that the pathomechanism differs from that of malignant hyperthermia induced by malfunction of sarcoplasmic reticulum.


[Gadolinium-MRI findings of two adrenoleukodystrophy cases treated with gamma-globulin]. Two cases of adrenoleukodystrophy were reported. We treated them with intravenous gamma-globulin infusion. MRI with gadolinium enhancement was performed before and after the therapy to evaluate the effect of gamma-globulin. Case 1 was a 19-year-old boy, who noticed left hemianopsia when he was 18 years old. Case 2 was a 36-year-old man, who developed ataxic gait and character change when he was 33 years old. Very long chain fatty acids in plasma and RBC membrane were elevated in both cases. On T2-weighted image of MRI, high signal lesions were seen in the white matter of occipital lobe in case 1, cerebellum, internal capsule, and around the corpus callosum in case 2. On T1-weighted image, the rim of every lesion was enhanced by gadolinium infusion. After the gamma-globulin therapy, gadolinium enhancement of the rim remarkably reduced in case 1. No reduction was observed in case 2. MRI findings of case 1 indicate the possibility that gamma-globulin may suppress the inflammation of the adrenoleukodystrophy.


[A case of chronic toluene intoxication with atrophy of cerebrum, cerebellum and brainstem on CT and MRI]. A 28-year-old man developed neurological disorders consisting of cerebellar symptoms and dementia over a period of 8 years of inhalation of toluene. He also developed bilateral optic atrophy. CT scan and MRI revealed atrophy of cerebrum, cerebellum and brainstem. The severity of neurological symptoms corresponded with the findings of CT and MRI. Furthermore, MRI (T2) showed reduced signal intensity in bilateral thalamus. This patient was also admitted to another hospital 2.5 years ago. Compared with the previous findings, present examinations showed significant progress of the atrophy of cerebrum and brainstem. It was suggested from the results of ABR that the disturbance of the brainstem was aggravated through this period.


[A case of topographical disturbance following a left medial parieto-occipital lobe infarction]. A 59-year-old man was admitted to our hospital for his sudden-onset right hemianopsia. Thirty days after the onset, neuropsychological examination revealed obvious topographical disorientation and mild optic ataxia. Magnetic resonance imaging showed abnormal intensity area at the left medial parietooccipital region and left splenium of the corpus callosum. Although single photon emission CT showed uptake decrement in the left hemisphere, almost normal uptake was observed in the right hemisphere. He could recognize landmarks, but fail to recognize the relative position of landmarks. Therefore, his topographical disorientation was considered to be due to perceptual disturbance, memory disturbance of relative position of landmarks, or both. He was right-handed with no sinistral relative, and showed dyslexia and dysgraphia early in his clinical course. The laterality index of the dichotic listening test revealed the right ear dominance. These results indicated that his left hemisphere was language dominant. His topographical disorientation could be caused by the medial parieto-occipital lesion in the dominant hemisphere.


[Wallenberg's syndrome due to vertebral artery dissection following minimal neck injury--report of two cases]. We described two cases of the lateral medullary syndrome (Wallenberg's syndrome) due to vertebral artery dissection following minimal neck injuries. The first case was a 45-year-old man, who hit his head and often rotated his head because of posterior neck discomfort. Two years after the injury, he suffered from sudden sharp neck pain, nausea, and vertigo, which was followed by left hand numbness and difficulty in walking due to the right lateral medullary syndrome. Angiography showed right vertebral artery dissection at the fourth segment. The second case, a 48-year-old man, suffered from neck pain immediately after he hyperextended his neck for painting a wall. Within several hours, he experienced left hand numbness and difficulty in walking due to the lateral medullary syndrome. Angiography showed a saccular aneurysm and dissection of the right vertebral artery at the fourth segment. In both cases, minor traumas were thought to be the causes of vertebral artery dissection. We surveyed previously reported 84 cases (men: 50, women: 34) of the vertebral artery dissection due to minor traumas. Seventy per cent of patients were in their third or fourth decade of life. The main causes of trauma preceding the dissection were neck manipulation especially chiropractics (52%). The third segment was most vulnerable. Delay in onset following neck trauma could be more than a week, but in most cases the delay was less than 24 hours. Cervical rotation and extension were thought to precipitate dissection.


[Spastic paraparesis and sensory disturbance improved by prednisolone therapy]. We reported a 65-year-old man whose sister was suffering from HTLV-I-associated myelopathy (HAM) and who presented slowly progressive spastic paraparesis, sensory disturbance in the feet, tremors and cerebellar ataxia. He was also positive for serum anti-HTLV-I antibody. He first showed a head tremor at the age of 3 years. He developed a spastic and ataxic gait when aged 15 years, and it became difficult for him to walk at the age of 50 years. Examination at 65 years showed a spastic and ataxic gait and scanning speech. Hyper-reflexia and Bahinski's signs were observed. Sensation in the feet was decreased. The anti-HTLV-I antibody titer in the serum was 1:512 by the PA method, and Western blot analysis revealed bands of P19, P24, P28 and P32. Examination of the cerebrospinal fluid (CSF), including oligoclonal bands, gave normal results. The CSF was negative for anti-HTLV-I antibody. CT and MRI of the head showed cerebellar atrophy. His sister was 60 years old. She had developed a spastic gait at the age of 15 years. Sensory defects and bladder dysfunction developed when aged 35 years. Hyper-reflexia, Babinski's sign and foot clonus were observed. Sensation in the feet was decreased. The urinary residual volume was increased. Ataxia was not observed. The anti-HTLV-I antibody titer in the serum was 1:8,192 by the PA method, and Western blot analysis revealed bands of p24, p28 and p32. Examination of the CSF, including oligoclonal bands, gave only normal results.(ABSTRACT TRUNCATED AT 250 WORDS)


[Acute hepatitis A (HA) presenting findings of meningoencephalitis]. A 39-year-old man, who had high grade fever and headache for 4 days was admitted to our hospital because of generalized seizure and disturbance of consciousness. He was pyrexial, but not icteric. Neurological examination revealed disorientation, nuchal rigidity and bilateral Babinski reflexes. Laboratory test results included the following: GOT 1,740 U/l, GPT 2,800 U/l, bilirubin 1.2 mg/dl, serum IgM-HA antibody cut-off index 6.8. CSF was clear, with 10 leukocytes/mm3 and protein level of 108 mg/dl. Head CT and MRI revealed no abnormality. An EEG demonstrated diffuse slowing. During the following 2 days, he had increased obtundation and labored breathing. In the second week of hospitalization his neurological conditions and liver function test results improved. A diagnosis of HA was confirmed by a finding of serum IgM-HA antibody. The neurological findings, CSF findings and clinical course indicated acute meningoencephalitis in association with HA. To our knowledge, there have been only 4 previous case reports of meningoencephalitis associated with serologically confirmed HA infection. HA virus infection might pass unnoticed, as many cases of HA infection remain anicteric or subclinical. Therefore, HA virus should also be considered as one of the etiological agents in meningoencephalitis.


[A case of Nasu-Hakola's disease with T2-weighted MRI finding of reduced signal intensity in the thalamus and putamen]. A 30-year-old female received a head injury at the age of 22 years. Subsequently neurological and psychiatric symptoms, such as personality change, urinary incontinence, dementia and gait disturbance developed. On admission, her cognitive function was severely impaired. Brain CT disclosed cerebral atrophy, dilatation of the lateral ventricle and calcification of the basal ganglia. Pathologically membranous structures were recognized in bone marrow. On the basis of these clinical findings, a diagnosis of Nasu-Hakola's disease was made. In this case, a T2-weighted MRI finding of reduced signal intensity in the thalamus and putamen was characteristic. This finding may be related to intracranial calcification.


[Involvement of the ventral horn cells in Guillain-Barré syndrome and chronic inflammatory demyelinating polyradiculoneuritis]. The lumbar ventral horn cells and myelinated fibers in the ventral spinal roots of Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyradiculoneuritis (CIDP) were morphometrically analyzed. In all six cases, central chromatolytic changes in the ventral horn cells were commonly observed. In addition, two out of four GBS cases and one of two CIDP cases showed a significant reduction in the ventral horn cell population, particularly in neurons with a large diameter. The cases with significant motoneuron loss also showed a remarkable reduction in the number of myelinated fibers in the ventral spinal roots, and severe axonal degeneration was observed in cases in acute phase. Astrogliosis of the ventral horn was also seen in some cases. The present study suggested that motoneuron loss in the primary demyelinating diseases like GBS and CIDP is the consequence of the axonal pathology of the motoneuron axons. These observations are helpful to understand motoneuron loss in certain motoneuron diseases with preferential involvement of lower motor neurons.


[Varicella-zoster virus-associated spinal myoclonus without skin lesions]. A 50-year-old woman was admitted to our hospital because of abnormal involuntary movement of upper abdomen. Three months before admission, she had suffered from left lateral chest pain without skin lesions for one week. The neurological examination on admission revealed myoclonus of upper abdomen, and hyperalgesia and thermohyperesthesia from T4 to T9. There was no weakness, the tendon reflexes were symmetrical and the plantar responses were flexor. The surface EMG disclosed the symmetrical, synchronous contractions of m. rectus abdominis and m. obliques externus abdominis. This spinal myoclonus reduced during sleep. The EEG, CT and MRI showed no abnormalities. Serum varicella-zoster virus (VZV) titers increased significantly on follow-up examinations. Clonazepam, 1.5 mg daily was effective in this patient. The myoclonus spontaneously disappeared without clonazepam in six weeks after onset, and at the same time the sensory disturbance also improved. From the neurological findings and clinical course, we consider this spinal myoclonus was probably elicited by involvement of the inhibitory interneurons of the dorsal horns, due to immune response to latent VZV infection but not to direct neuronal destruction by VZV. Spinal myoclonus should be recognized as the spectrum of neurological disease associated with VZV even in the absence of skin lesions.


[Unilateral persistent hyperhidrosis after ischemic stroke]. A 64-year-old right hemiplegic woman, who had been treated for hypertension for 15 years, was admitted to our hospital. Neurologic examination on admission disclosed right hemiplegia and motor aphasia; however, ophthalmoparesis, pupillary abnormality, and blepharoptosis were not evident. Excessive sweating on the right side of the body, which was most marked on the face, was observed. Amount of sweating on the left side of the body was normal. Unilateral hyperhidrosis persisted for more than 2 months. MRI revealed hemorrhagic infarctions in the left basal ganglia, internal capsule, thalamus, hypothalamus, and medial part of the cerebral peduncle. 123I-IMP SPECT disclosed hypoperfusion in the left striatum, thalamus, occipital cortex, and right cerebellar hemisphere. Cerebral angiography revealed arteriosclerotic changes in the basilar artery, but that the left posterior cerebral artery and its branches were not occluded. Unilateral persistent hyperhidrosis is rare after ischemic stroke. Hypothalamic lesion was thought to be responsible for the hyperhidrosis in this patient. As the hypothalamus receives its blood supply from the posterior cerebral artery, unilateral persistent hyperhidrosis may be an important sign of cerebral infarction in the posterior cerebral artery region.


[A case of giant pigmented nevus with multiple meningiomas]. A 36-year-old female had a giant congenital pigmented nevus on her anterior trunk. She complained of muscle weakness of the right arm and leg in August 1988, and she was admitted to our hospital to take medical examinations in September 1988. Neurological examination revealed right hemiparesis and exaggerated deep tendon reflexes. Three small falx meningiomas were shown on CT scans and MR images, but they did not appear to be causes of her symptoms. CT-myelography and MR images revealed an intradural extramedullary tumor spreading from the foramen magnum to C2. Oncotomy and C1 laminectomy were performed. Histological finding was compatible with transitional meningioma. Neurological symptoms markedly improved after operation. This patient is considered as a case of neurocutaneous syndrome with central nervous system tumors. Considering that both giant pigmented nevus and meningioma originate from neural crest, they appear to be closely related each other. Such a combination of giant pigmented nevus and meningioma has not yet been reported.


Scintigraphic diagnosis of bile leakage after laparoscopic cholecystectomy. A prospective study. To assess the role of Tc-99m IDA cholescintigraphy in diagnosing bile leakage and bile obstruction after laparoscopic cholecystectomy, 51 studies were performed in 51 patients on the first postoperative day. Two different radioactive bile acid analogs were used, Tc-99m HIDA and Tc-99m trimethylbromo IDA. Scintigraphic findings were correlated with the clinical conditions. Results of seven out of 51 cholescintigrams were abnormal, showing accumulations of activity in the right paracolic gutter. Of these seven patients, only three had clinical symptoms consisting of more than normal postoperative abdominal pain and peritoneal irritation. The other four patients had minimal abnormal accumulation in the right paracolic gutter and showed no clinical signs postoperatively. Complete common bile duct obstruction or other bile duct-related complications, except for bile leakage, were not observed. Cholescintigraphy is feasible for the early detection of bile leakage and bile flow obstruction after laparoscopic cholecystectomy in patients with increased postoperative abdominal discomfort.


Transient unilateral reverse ventilation/perfusion mismatch in a patient with lung cancer. The authors report a transient, unilateral reverse ventilation/perfusion (V/P) mismatch in a patient with squamous cell lung cancer. The right lung was well perfused but not ventilated (unilateral reverse V/P mismatch). However, lung imaging performed 3 days later demonstrated the absence of both perfusion and ventilation (V/P match). Reverse V/P mismatch may be a transient process.


P-32 bremsstrahlung SPECT helps assess intracavitary therapy. A patient underwent intracavitary P-32 chromic phosphate therapy for a chest tumor. Tc-99m sulfur colloid instilled before the P-32 demonstrated uniform distribution of activity throughout the right pleural space, and the P-32 was immediately administered. Ten days later, SPECT imaging using bremsstrahlung radiation of the P-32 showed an unexpected loculation of the P-32. A subsequent chest CT scan demonstrated pleural infolding and fluid localization in the same area as the P-32, indicating that the bremsstrahlung SPECT study had, in fact, documented the final localization of the P-32, which was unexpected and different from the initial localization. The procedure used in this case may be of value in documenting the ultimate distribution of intracavitary P-32.


Wound dressing activity mimicking infection on labeled leukocyte imaging. Although labeled leukocyte imaging is an extremely useful technique for the localization of infection, false-positive results in inflammatory conditions where no infection exists have been described. False-positive results secondary to bleeding have also been reported. The authors recently observed intense uptake of labeled cells in the wound dressings of two patients undergoing leukocyte imaging. Repeat imaging after the removal of these dressings confirmed that the activity seen was in the dressings and did not represent focal infection, as originally thought. Based on these observations, the authors think it prudent to remove such dressings before performing leukocyte imaging.


Pitfalls of bone mineral density evaluation by dual-photon absorptiometry. Material absorbing photons aligned with the lumbar vertebrae can create falsely elevated measurements of bone mineral density during dual-photon absorptiometry. Three cases illustrating this phenomenon are presented. Although bone mineral density was overestimated in each case, calculated fracture risk was normal in two cases and greatly increased in the third. Photon-absorbing material can create overestimates of bone mineral density during dual-photon absorptiometry, even when a greatly increased fracture risk is computed.


Ice cream scooper's hand. Report of an occupationally related stress fracture of the hand. Stress fracture of the hand is uncommon but can be a significant source of morbidity if not promptly diagnosed. The authors present a case of metacarpal stress fracture in which the occupational history was key to the diagnosis and management of long-standing hand pain.


Pott's puffy tumor. Scintigraphic findings. The authors describe the scintigraphic findings of bone and Ga-67 imaging performed on three patients thought to have Pott's puffy tumor. Two patients did indeed have it, but the third patient's "puffy tumor" was a soft tissue abscess.


Intracerebral platelet accumulation as evidence for embolization of carotid origin. Arterio-arterial embolism of carotid origin is one major cause of cerebral ischemia. To evaluate the role of blood platelets in this process, In-111 labeled platelet scintigraphy was performed in a series of 250 patients. Of this number, one patient with an 80% carotid stenosis and a normal intracerebral angiogram suffered a transient ischemic attack (TIA) several hours after the injection of radiolabeled platelets. The scintigram showed a pathologic platelet accumulation in the symptomatic carotid area as well as in the ipsilateral brain hemisphere. The authors conclude that this scintigraphic finding of hemispheric platelet aggregates recorded directly after a clinically observed TIA, together with previous observations of retinal emboli after amaurosis fugax attacks, provides strong evidence for the arterio-arterial embolic mechanism of TIA.


Early detection of Rasmussen's syndrome by brain SPECT imaging. The authors describe a patient with Rasmussen's syndrome detected by grossly abnormal results of Tc-99m HMPAO SPECT brain imaging obtained with a single-headed camera. Results of magnetic resonance imaging and cerebrospinal fluid examinations were normal.


Reverse crossed cerebellar diaschisis in partial complex seizures related to herpes simplex encephalitis. Tc-99m HMPAO brain SPECT was performed in a patient who had partial complex seizures for 1 year after successful acyclovir treatment of biopsy-proven herpes simplex encephalitis 2 years earlier. In spite of antiepileptic medications, her seizures were intractable and occurred daily. Tc-99m HMPAO was administered intravenously while she was having subclinical seizures, and brain SPECT demonstrated an area of hyperperfusion in the right temporal lobe medially and in the contralateral cerebellum. This reverse of the crossed cerebellar diaschisis phenomenon in epileptic disorders has not previously been documented.


Normal uptake in a gravid uterus on Tc-99m DTPA imaging. A 17-year-old female kidney transplant patient was admitted to the hospital with a fever and right lower quadrant pain. Although she was 14 weeks' pregnant, renal DTPA imaging was performed because graft rejection was suspected. The study revealed fetal uptake of DTPA medial to the transplanted kidney. This has not been previously reported. Uptake in a normal uterus has been described using Tc-99m pertechnetate, Tc-99m glucoheptonate, and Tc-99m MDP. It is essential to recognize uptake in the gravid uterus and to differentiate it from uptake secondary to a pathologic entity.


Vigabatrin. Clinical pharmacokinetics.

Vigabatrin. Clinical pharmacokinetics. Vigabatrin is a structural analogue of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). It is supplied as a racemic mixture, with the S(+) enantiomer possessing pharmacological activity. [R,S]-Vigabatrin plasma concentrations can be estimated using high-performance liquid chromatographic methods. Only gas chromatography-mass spectrometry methods allow quantification of the S(+) and R(-) enantiomers. Vigabatrin was rapidly absorbed reaching peak concentrations within 1 to 2h. Area under plasma concentration-time curves indicated dose-linear pharmacokinetics. There was no effect of food on the absorption of vigabatrin. The absorption characteristics of the enantiomers were similar to those of the [R,S]-vigabatrin. No chiral inversion was detected after administration of the pure S(+) enantiomer. Vigabatrin is not protein bound. The apparent volume of distribution of [R,S]-vigabatrin was approximately 0.8 L/kg. Despite the lack of protein binding, cerebrospinal concentrations of the [R,S]-vigabatrin were only 10% of the plasma concentration 6h after a single oral dose. The half-life of [R,S]-vigabatrin was between 5.3 and 7.4h, the half-life of the enantiomers were 7.5 and 8.1h for the S(+) and the R(-) forms, respectively. The major route of elimination was renal excretion; urinary recovery of the [R,S]-vigabatrin was close to 70%. Pharmacokinetic studies in epileptic children did not show any significant effect of maturation on the disposition of the S(+) enantiomer: the half-life and the renal clearance were similar to adult values. Data suggest a lower bioavailability in children. In adults with epilepsy, the half-life of the [R,S]-vigabatrin ranged from 4.2 and 5.6h, similar to that measured in healthy adults. In elderly nonepileptic volunteers the pharmacokinetics of the enantiomers of vigabatrin showed delayed absorption, a major increase in peak concentration and a prolonged half-life. These changes were attributed to decreased renal clearance of vigabatrin. A nonlinear relationship between renal clearance and creatinine clearance was suggested. Vigabatrin caused a 20% fall in plasma phenytoin concentrations, the mechanism of which has not been elucidated. There were no other interactions with most concurrently administered anticonvulsants. The usual dosage of vigabatrin as add-on treatment in adults is 2 to 4g daily. Higher dosages up to 80 mg/kg daily were required in children. A dosage adjustment was recommended in any patient with decreased renal clearance. Although anticonvulsant effects were clearly related to dosage, monitoring of plasma concentrations of vigabatrin as a guide to dosage is unlikely to be of as much value as with other antiepileptic drugs. The action of the drug long outlasts its presence in plasma.


Liposomal and lipid formulations of amphotericin B. Clinical pharmacokinetics. Amphotericin B remains a very important drug for the treatment of fungal infections despite its toxicity. Encapsulation of amphotericin B into liposomes appears to reduce the toxic effects and to improve the clinical efficacy, allowing higher dosages to be given. The exact mechanism behind the reduced toxicity is not yet known. Amphotericin B is widely distributed after intravenous administration as the deoxycholate solubilisate. The highest concentrations are found in the liver, spleen and kidney. Protein binding and binding to the tissues is very high. The fate of the drug in the body is not known in detail. Renal and biliary excretion are both low and no metabolites have been identified. The drug is still detectable in the liver, spleen and kidney for as long as 1 year after stopping therapy. The pharmacokinetics of the different liposomal amphotericin B or lipid complexes of amphotericin B, which were recently developed, are quite diverse. A number of these preparations, such as amphotericin B lipid complex (ABLC), 'AmBisome' and amphotericin B colloidal dispersion (ABCD) are in clinical development. Their pharmacokinetics depend to a large extent on the composition and particle size of the liposomes or lipid complexes. Relatively large structures such as ABLC are rapidly taken up by the mononuclear phagocyte system, whereas smaller liposomes remain in the circulation for prolonged periods. In all studies only the total amphotericin B (both free and liposome- or lipid-associated) concentrations were determined. There is a need for studies correlating clinical efficacy and tolerability of liposomal amphotericin B with the pharmacokinetic properties of these formulations.


Correlating CBC profile and infectious outcome. A study of febrile infants evaluated for sepsis. The cases of 1,009 febrile infants who were evaluated for sepsis as outpatients during a seven-year period were reviewed to correlate their complete blood count (CBC) profiles with the infectious outcomes. Eighty-one infants had serious bacterial infections (SBIs); the remainder (928) were culture-negative. The infants with SBIs had a significantly greater mean total white blood cell (WBC) count and absolute band count (ABC) than did those who were culture-negative, whereas the difference in mean percent of polymorphonuclear leukocytes was not significant. The sensitivity of the ABC was significantly superior to that of total WBC count in predicting the outcome of SBI. The diagnostic data provided by the ABC can aid physicians in determining the predictive value of CBC profiles for infectious outcome in febrile infants receiving outpatient sepsis evaluation.


The perioperative management of pheochromocytoma in children. The perioperative experiences of 15 children and adolescents who underwent a total of 18 surgical procedures for resection of a pheochromocytoma were analyzed to determine clinical or hemodynamic events associated with intraoperative or postoperative complications. Of the pre- and intraoperative factors assessed, only preoperative resolution of symptoms and normalization of blood pressure were predictive of uncomplicated outcome. No intraoperative factors were statistically associated with outcome, but the four patients with complicated outcomes had had aggressively administered intraoperative fluids. Noninvasive measures of cardiac function did not help predict outcome; however, echocardiography results were available only for six patients. Two of the patients with complicated outcomes had cardiac dysfunction, suggesting undiagnosed catecholamine-induced cardiomyopathy in the other two with complicated outcomes. Intraoperative fluids should be given based on intraoperative blood pressures, the presence or absence of prior adrenergic blockade, and assessment of preoperative myocardial function. If preoperative myocardial dysfunction is revealed, intraoperative measurement of right atrial and pulmonary capillary wedge pressures may be indicated.


Glucuronidation of drugs. A re-evaluation of the pharmacological significance of the conjugates and modulating factors. Glucuronides of drugs are considered to be generally inactive and rapidly eliminated. Therefore, these metabolites are often not taken into account in evaluating drug effects. The present review describes examples of both direct and indirect contributions of glucuronides to net drug effects. Multiple lines of evidence indicate that morphine-6-glucuronide has analgesic activity. This compound has a high affinity to the mu-receptor, is capable of penetrating the blood/brain barrier and is a potent analgesic after administration to patients. Indirect activity of glucuronides may consist of a systemic cycle in which an active parent compound is derived from the glucuronide by enzymatic action. Such systemic cycling has been demonstrated for clofibric acid. In addition, some acyl glucuronides are subject to intramolecular rearrangement and the resulting metabolites are resistant to beta-glucuronidase. Covalent protein binding of glucuronides by different mechanisms may contribute to drug toxicity and immune responses. If glucuronides are accepted as potential modifiers of net drug action it is important to determine what factors modulate disposition of these compounds. Therefore, the later section of this review describes glucuronidation under different pathophysiological conditions. Examples for alterations of the rate and/or extent of glucuronidation by concurrent diseases processes, age and coadministration of other drugs are provided.


Do adolescents understand what physicians say about sexuality and health? The high rates of adolescent sexual activity, often with adverse medical and social outcomes among minority females, prompted us to survey 160 girls between the ages of 13 and 18 concerning their knowledge of reproductive health terms, anatomy, and body functions. All were patients in a clinic in an inner-city hospital. We hypothesized that adolescents who were older, sexually active, and/or had received formal sex education would be better informed. We used a two-part, self-administered questionnaire. The first part focused on definitions of nine common medical and reproductive health terms; the second focused on definitions of unlabeled anatomic drawings of male and female genitourinary systems. The subjects' responses revealed their lack of information as well as a great deal of misinformation. No statistical differences in knowledge were found related to age, sexual activity status, or formal sex education. Many patients knew only nontechnical and slang terms and did not understand medical terms used by physicians in the clinic. Clinicians should not assume similar patients (minority and poor) know or understand their terminology and should use simple and, if necessary, explicit vocabulary.


Emergence of invasive group A streptococcal disease among young children. Eight cases of invasive group A streptococcal disease in young children were reported over a three-month period, February to April 1990. The spectrum of clinical disease included: pneumonia with bacteremia (two patients), osteomyelitis/septic arthritis (three patients), epiglottitis/supraglottitis (two patients), and sepsis without a focus (one patient). Three cases followed chicken pox. Three children were in shock at the time of presentation, including one child who had a toxic shock-like appearance. Only four children had pharyngitis. Bacteremia was confirmed in three children and presumed in another three. All the subjects survived. Four isolates of group A streptococci were tested for exotoxin A, B, and C (A-0, B-4, C-1) production. These data confirm the reappearance of a highly invasive strain of group A streptococci capable of producing a variety of clinical diseases, including bacteremia and shock, in a significant proportion of victims.


Learning by teaching. A resident-taught oral therapy program for acute diarrhea. An educational program on oral rehydration therapy (ORT) for diarrhea was instituted in our residents' continuity clinics to evaluate the impact that residents teaching parents would have on the knowledge and practices of both groups. Sixty-one residents and 287 parents answered the initial written questionnaire before the teaching program began, and 48 residents and 147 parents completed a second questionnaire at the end of the program. Nineteen residents in two clinics were told to participate frequently in teaching the parents, while 29 residents in three other clinics were given no such instructions. The parents were divided into three groups: 58 received teaching and an instructional handout on the management of diarrhea; 73 received only the instructional handout; and 16 received neither intervention. The 19 "teaching" residents had a significantly improved overall score compared with the "nonteaching" residents (p < .03). No improvement was found in the scores of the 58 parents who received teaching compared with those of the 89 parents who received either a handout or no educational intervention. We conclude that active teaching of ORT may improve the knowledge and practices of residents, but that single teaching encounters, whether or not accompanied by written instructions, may have little impact on parents.


Doppler ultrasound of the hepatic veins: normal appearances. Doppler ultrasound of the hepatic veins gives a pulsatile velocity profile which mirrors the cardiac cycle. We describe the physiological basis for the complex waveform and suggest a venous pulsatility index (VPI) which can be used to quantify it. We have studied normal volunteers under differing conditions to establish a normal range of VPI. This provides a baseline against which abnormal patterns of hepatic vein Doppler can be judged.


The role of hepatic vein Doppler in diagnosing acute rejection following paediatric liver transplantation. Serial Doppler ultrasound examinations of the hepatic veins were performed on 50 consecutive paediatric liver transplants. Damping of the normally pulsatile signal was observed in 23 of the 32 biopsy-proven episodes of rejection. In 10 episodes, the reduction in hepatic vein pulsatility preceded clinical and biochemical evidence of rejection by up to 36 h. Seven cases had damped signals throughout the post-operative period which precluded assessment by this method. In two patients the hepatic vein signals remained pulsatile despite rejection, one patient having unsuspected tricuspid regurgitation, and the other a stenotic IVC anastomosis. In the 35 liver transplants with normal pulsatility, hepatic vein Doppler proved to be a valuable indicator of acute rejection during the first 2 weeks following transplantation (sensitivity 92%, specificity 100%, positive predictive value 100% and negative predictive value 83%).


Duplex and colour flow sonography in the diagnosis of post-biopsy arteriovenous fistulae in the transplant kidney. Arteriovenous fistulae are a common sequel to percutaneous biopsy of the transplant kidney. The majority close spontaneously, but a proportion progress and may require embolization or surgical closure. They are characterized by a very pulsatile (arterialized) venous flow. The arteries sometimes demonstrate a low resistive index and/or high velocities, but normal values may be encountered. On colour flow Doppler the most characteristic appearance is a mosaic of colour due to a combination of tissue vibration and turbulence.


Transjugular liver biopsy: a review of 200 biopsies. Transjugular liver biopsy was performed in 200 patients for whom percutaneous biopsy was contraindicated because of coagulation disorders (36%), ascites (32%) or for the work-up of portal hypertension (32%). An adequate biopsy allowing a histological diagnosis was obtained in 155 patients (77%). The biopsy was inadequate in 13 patients (6.5%). In 32 patients (16%) the biopsy failed. Complications occurred in 18 patients (9%). Twelve (6%) patients developed liver capsule perforations which were immediately embolized without complication. Inadvertent carotid artery puncture and supraventricular tachycardias occurred in three patients each. Transjugular liver biopsy is a valuable technique which provides information which would otherwise be unavailable in those patients for whom percutaneous biopsy is considered unsafe.


Contrast media-induced effects on blood rheology and their importance in angiography. Factors which alter blood viscosity may have important consequences during angiography. The differential effects of various concentrations of five different radiocontrast media on the viscosity characteristics of erythrocyte-plasma suspensions were made over a range of applied shear rates. The results showed that, at both high and low shear rates, the rate of change of viscosity with contrast concentration differs markedly between the various types of contrast media. The conventional ionic monomers caused most disturbance to blood viscosity. The monoionic dimer hexabrix was least disturbing to the viscometric characteristics of blood, and the newer non-ionic monomers were intermediate in their effects. Significant effects on blood viscosity may be caused by radiocontrast agents during a number of in vivo angiographic situations, in particular: early after contrast bolus injection into large vessels, in the microcirculation after selective injections, and during angioplasty procedures.


The effect of iodixanol, a new isotonic contrast agent, on femoral blood flow in man. Both ionic and non-ionic contrast media (CM) injected intra-arterially produce peripheral vasodilatation and a sensation of heat or even pain. This effect has been considered to be predominantly related to the osmolality of the CM used. Iodixanol is a non-ionic dimeric CM which can be made isotonic with blood at iodine concentrations up to 400 mg/ml. To assess the degree of peripheral vasodilatation following aortic injection of iodixanol, the change in femoral artery blood flow has been assessed non-invasively. Dupex ultrasound flow-velocity records were taken from the contralateral femoral artery in 10 patients undergoing transfemoral aortography. Volume flow, mean velocity, pulsatility index and peak systolic velocity were continuously recorded before and up to 2 min after injection of 60 ml of iodixanol at an iodine concentration of 320 mg/ml (iodixanol 320). Transient changes consistent with vasodilatation were observed in all patients. The greatest changes were observed during the time period 18-24 s after injection. Volume flow, mean velocity and pulsatility index all changed significantly from baseline (mean changes of 80.6%, 73% and -42.7% respectively). Peak systolic velocity did not change significantly. Intra-arterial injections of isotonic iodixanol 320 produces a significant increase in femoral blood flow in man. Factors other than hypertonicity must therefore be implicated in the vasodilatory effect of contrast media.


CT-guided drainage of pelvic abscesses: the peranal transrectal approach. Five patients with deep pelvic abscesses underwent computed tomography (CT)-guided catheter drainage using a transrectal approach. The use of an outer removable plastic sheath over the catheter to facilitate positioning and prevent inadvertent damage to the mucosal wall is described. This new approach using CT guidance is discussed and the alternative routes reviewed.


Direct puncture venography in subcutaneous cavernous haemangiomas. The conventional assessment of subcutaneous cavernous haemangiomas by venography, arteriography, ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) is often unsatisfactory and fails to show either the extent of the lesion or its feeding and draining vessels. We describe a direct puncture venography technique which successfully delineated the lesions in six patients. The technique was easy to perform and no complications occurred.


Can we reduce the number of routine films required for contrast sialography? A reduction in the number of radiographs for many investigations has been advocated. This study aims to assess the need for control views in sialography and whether the post-contrast lateral oblique radiograph would be satisfactory, at least initially, as the sole standard post-contrast film.


Airways obstruction and bronchiectasis: correlation with duration of symptoms and extent of bronchiectasis on computed tomography. Many patients with bronchiectasis have diffuse airways obstruction and this may be the dominant symptom. This study was performed to assess whether the severity of airway obstruction in these patients is related to duration of bronchiectatic symptoms or to the extent of bronchiectasis demonstrated by computed tomography (CT). Twenty-six patients were studied. The severity of airflow obstruction was measured by standard physiological testing and the extent of bronchiectasis demonstrated by CT was assessed using a scoring system. Correlation was measured by Kendall's rank correlation coefficient. A highly significant correlation between FEV1 and CT score was demonstrated and a significant correlation was also observed between FEV1 and duration of symptoms. A weak correlation was present between CT score and symptom duration.


High resolution computed tomography (HRCT) in emphysema associated with alpha-1-antitrypsin deficiency. Alpha-1-antitrypsin (AAT) deficiency is an inherited disorder associated with an increased prevalence of pulmonary emphysema. To date there has been no description of the appearances on CT of the emphysema associated with AAT deficiency. We have reviewed the CT scans of 17 patients with proven AAT deficiency. Eleven out of 17 were examined with HRCT. The CT features were correlated with those on chest radiography. Areas of low density corresponding to parenchymal destruction and reduced perfusion, and attenuation of the pulmonary vasculature were present in all cases. Frank bulla formation occurred in 7/17 patients and was not a major feature. A striking CT finding was bronchial wall thickening and/or dilatation in 7/17 patients with gross cystic bronchiectasis in one patient. In contrast to appearances on chest radiography the upper zones were affected in all cases (17/17) and fine section scanning was particularly valuable in demonstrating changes in these less severely affected regions. Estimation of the extent of disease correlated well with abnormal lung function tests.


Radiological investigation in laparoscopic compared with conventional cholecystectomy--an early assessment. The implications of laparoscopic cholecystectomy (LC) for radiology were assessed by comparing imaging investigations in 48 LC and 48 conventional cholecystectomy (CC) patients. In addition, we attempted to identify findings on pre-operative ultrasound (US) which predicted operative difficulties at LC. There were no per-operative or T-tube cholangiograms in the LC patients, but otherwise the pattern of investigation was similar in both groups. Forty of the 48 CC patients underwent cholangiography (per-operative cholangiography in 36, endoscopic retrograde cholangiopancreatography (ERCP) in two, and both in two) demonstrating calculi in eight (16.7%) cases. Only four LC patients had cholangiography (ERCP in all cases) demonstrating common bile duct (CBD) calculi in one (2.1%) case. Ultrasound failed to identify the gall-bladder with certainty in three of the five failed LC cases. Neither gall-bladder wall thickness, contraction nor calculus size on pre-operative US served as predictors of other per-operative difficulties. Our results indicate that there may be some patients with retained CBD calculi in the LC group. The role of pre-operative US in predicting operative difficulties needs further assessment in a prospective study.


Ultrasonic and computed tomographic appearances of paraganglioma simulating pancreatic mass. We report two cases of paraganglioma in which the tumour was situated adjacent to the head of the pancreas simulating a pancreatic mass lesion. The absence of biliary or pancreatic duct dilatation on ultrasound in the presence of a large mass suggested a retroperitoneal tumour rather than a pancreatic adenocarcinoma. Functional activity in these tumours is common and should be excluded before biopsy.


Technical report: percutaneous cholecystostomy in acute acalculous cholecystitis. Acute acalculous cholecystitis is a significant cause of morbidity and mortality in patients with other serious illnesses (Howard, 1981) and the mortality rate after surgical cholecystostomy may reach 15% (McGahan and Lindfors, 1989). Radiologically controlled percutaneous cholecystostomy is a safe, minimally invasive, procedure which may be curative (McGahan and Lindfors, 1989; Berger et al., 1989). Both cases described here were successfully treated by percutaneous cholecystostomy. A modified Seldinger technique was used in one and a direct 'trocar' puncture in the other. Percutaneous cholecystostomy, which is technically relatively straightforward, is now the treatment of choice for acute acalculous cholecystitis.


Case report: multisystem failure following intravenous iopamidol. A case of life-threatening adverse effects following intravenous administration of a non-ionic contrast medium is reported. The patient, a 68-year-old diabetic hypertensive male with dyspnoea and cough had an abnormal chest radiograph, revealing congestive heart failure and an enlarged right hilum. Computed tomography (CT) of the chest was performed using 100 cm3 of intravenous iopamidol. Within half an hour the patient developed abdominal cramping, vomiting, and diarrhoea, followed by hypotension, tachycardia, fever to 40 degrees C, and delirium. His course was complicated by disseminated intravascular coagulation, rhabdomyolysis, renal failure, respiratory arrest, and atrial fibrillation. There was no evidence of infection, neoplastic disease, or myocardial infarction. Over the next month the patient slowly recovered. One other case report implicates a contrast agent with a similar syndrome. The features of this case fulfil the criteria for a probable adverse drug reaction of a type and severity rarely encountered.


Case report: superior vena cava obstruction complicated by central venous thrombosis--treatment with thrombolysis and Gianturco-Z stents. Expandable wire stents can provide effective palliation of superior vena cava obstruction (SVCO). We describe a case of SVCO unresponsive to radiotherapy and chemotherapy, which was complicated by extensive central venous thrombosis. Successful thrombolysis occurred with low-dose streptokinase allowing subsequent stent placement.


Case report: taste of success in thyroglossal fistulography. Thyroglossal fistulography is poorly documented in the radiological literature. An illustrative case is presented, highlighting the technique employed and the significance of its findings. The taste of contrast medium as it spills over the tongue is a useful additional sign in the successful demonstration of a fistulous communication. The contribution of fistulography to the accurate diagnostic work-up of patients undergoing the Sistrunk procedure is discussed.


Case report: granulocytic sarcoma (chloroma) presenting as a cerebellopontine angle mass. Granulocytic sarcomas (chloromas) are rare, solid extramedullary tumours composed of granulocyte precursors occurring in association with granulocytic leukaemia. A cerebellopontine angle granulocytic sarcoma in a 4-year-old child presenting with unilateral facial palsy is reported. The computed tomographic (CT) findings are described, with a review of the literature, and the significance of early diagnosis is discussed.


Case report: solitary haemangioblastoma of the fourth ventricle in an adolescent male. We report a solitary haemangioblastoma arising from a pedicle in the wall of the fourth ventricle of the brain, which we believe to be the first report of haemangioblastoma occurring in this location. Computed tomography (CT), angiography and magnetic resonance imaging (MRI) made possible accurate pre-operative tumour identification and localization which facilitated a minimally invasive surgical resection.


Case report: tailgut cyst--assessment with transrectal ultrasound. Tailgut cysts are derivatives of the embryonic post-anal gut. Usually asymptomatic, they are discovered in adult life as an incidental retrorectal mass. Complications include infection, with the formation of retrorectal abscesses and occasionally and fistulae, and a long-term risk of malignant change, which means that once discovered surgical excision is advised. We present a case that was assessed pre-operatively with transrectal ultrasound. The findings were of a well defined cystic lesion, with no evidence of invasion. We believe that transrectal ultrasound is of value in assessing retrorectal lesions.


Percutaneous transluminal angioplasty of the subclavian and axillary arteries: initial results and long term follow-up. The early and long term outcomes of 25 subclavian and axillary angioplasties in a series of 19 patients treated at one centre over a period of 10 years were assessed. The eventual outcome was long lasting improvement in most cases. Two of 25 PTAs were technical failures as defined as > 30% residual stenosis. Twenty-three of 25 PTAs were technical successes: 17 of these were first procedures, one was a repeat after an initial failure, two were repeats for restenosis and three were for separate new lesions. Clinically, 13 of the 19 patients were asymptomatic at long term follow-up. Four had only occasional, mild symptoms (in one of those they were due to shoulder arthropathy). Two patients had technically successful dilatations but developed problems with arterial occlusion distally which in one patient required amputation of that limb.


Thrombin-soaked embolization coils: the effect on whole blood clotting time. Embolization coils are well established as embolic agents for the treatment of various conditions. Several authors have commented on the increased 'thrombogenicity' of coils following soaking in thrombin solutions. We have carried out an in vitro study, carefully measuring the effect on whole blood clotting time (WBCT), of soaking coils in thrombin solutions of different concentrations (100, 200, 400, 1000 U/ml). Untreated steel coils are shown to have clot promoting activity (CPA) in vitro, reducing WBCT from 14.85 min to 5.53 min. Passing the coils down a saline-filled catheter slightly reduces their CPA, but not significantly (p = 0.21). With thrombin concentrations above 100 U/ml, a significant reduction in WBCT is recorded, but although there is a trend of increasing CPA with increasing thrombin concentration from 200-1000 U/ml, a plateau in WBCT is seen, and the difference is not significant. It therefore appears that the clot promoting activity of embolic coils is significantly increased by soaking them in a relatively weak thrombin solution. The use of such a solution (e.g. 200 U/ml) in vivo would have obvious value in limiting the potential systemic effects of thrombin.


Renal biopsy in diffuse renal disease--experience with a 14-gauge automated biopsy gun. The diagnostic and complication rates of 104 percutaneous renal biopsies performed for diffuse renal disease in native kidneys were retrospectively reviewed. Biopsies were performed by one radiologist using continuous ultrasound guidance and a 14-gauge biopsy needle in an automated gun (Biopty TM, Radiplast TM, Uppsala). 103 of 104 (99%) biopsies resulted in adequate tissue for a definitive histological diagnosis which improves on previously published diagnostic rates. Four patients (3.8%) experienced transient macroscopic haematuria. There were two symptomatic peri-renal haematomas, both of whom required transfusion, and one arteriovenous fistula which was successfully embolized (total 2.9% significant complications). Our results compare favourably with results using more conventional techniques. We suggest that use of real-time ultrasound with the 14-gauge Biopty needle should be the method of choice for percutaneous renal biopsy in adults.


The lateral neck radiograph in suspected impacted fish bones--does it have a role? A double blind trial, using lateral neck radiographs of 100 patients with proven impacted fish bones and 100 normal cases, was conducted to assess the sensitivity, specificity and positive predictive value of radiography for impacted fish bones. Values of 25.3%, 86.3% and 72.7% respectively were obtained. The results are correlated to the clinical findings and reasons for the poor performance of radiography are discussed. It is recommended that routine radiography for suspected impacted fish bones should be abandoned.


Is radiology a 'nine to five' specialty? The role of the radiologist in 'out of hours' radiology was prospectively studied in a single Scottish Health Board for a continuous 6 month period. Six hundred and sixty seven procedures were performed by radiologists. Computed tomography (CT) (274, 41%), ultrasound scans (190, 28.5%) and vascular/interventional procedures (60, 9%) were the most frequently performed procedures. Trauma accounted for 139 (24%) of all 'out of hours' work and overall 365 (54.7%) procedures yielded an abnormality. The workload varied widely between hospitals from two procedures per 100 beds to 137 procedures per 100 beds. Similarly the input from individual radiologists was very variable. A registrar was present for 227 (34%) procedures, a senior registrar for 360 (54%) and a consultant for 138 (20%) (there being two radiologists present for 8.7% of procedures). 'Consultant only' radiology departments offering a full radiological service may expect a substantial 'out of hours' commitment.


Case report: ultrasound appearances of a malignant mesothelioma of the tunica vaginalis testis. A case of a 91-year-old gentleman who developed massive scrotal swelling secondary to malignant mesothelioma of the tunica vaginalis testis is presented. Preoperative sonography was performed and the findings and difficulty in establishing the pathological diagnosis are discussed.


Case report: tuberculous colitis mimicking Crohn's disease. Although intestinal tuberculosis is rare in this country, increasing numbers of patients are now being seen, particularly in the immigrant population. We present the history of a lady who had acute diarrhoea and in whom the radiological and endoscopic findings looked very similar to those seen in Crohn's disease. The radiological presentation included widespread aphthous ulceration, a feature that has rarely been reported in tuberculous colitis.


Case report: perforation of angioplasty balloon by Palmaz stent. Intravascular stents are recognized to be of value in maintaining patency in resistant stenoses, recanalized occlusions, and when intimal dissection has occurred during balloon angioplasty [1,2,3]. Apart from early thrombosis, complications are relatively infrequent. We report a case of perforation of an angioplasty balloon during iliac angioplasty by a Palmaz stent sited in the contralateral iliac artery.


Case report: hepatic ultrasound findings in a case of toxocariasis. Multiple hypoechoic areas within the liver may be caused by a large variety of disorders. We report a case of Toxocara infestation which produced such an appearance within the liver of an 18-month-old child. We believe that this is the first report of Toxocara granulomata detected by ultrasound, and suggest that ultrasound examination may provide a useful diagnostic clue to this disease.


Case report: calcification of genioglossus: a painful radiographic finding. Resorption of the edentulous mandible can lead to the genial tubercles taking up a relatively superficial position. A case is presented where resorption was accompanied by calcification of the insertion of genioglossus resulting in the development of a painful mass in the floor of the mouth, whose nature could only be determined radiographically.


Case report: paraganglioma of the cauda equina. The clinical, radiological and pathological features of a paraganglioma of the cauda equina are described, including magnetic resonance imaging features. The literature is reviewed and discussed.


Case report: amoebic liver abscess complicated by a hepatoduodenal fistula. Amoebic liver abscess (ALA) is a common extra-intestinal presentation of amoebiasis caused by Entamoeba histolytica. The liver abscess may be complicated by rupture into adjacent structures. Common organs involved include thorax, peritoneum and pericardium. Rupture into the gastrointestinal tract is extremely rare. We report a patient who developed a hepatoduodenal fistula complicating an amoebic liver abscess. Suspicions were raised on finding air in the liver abscess on ultrasound scanning. Diagnosis was confirmed on a water-soluble (Gastrografin) swallow (Fig. 1 a,b). Complications of ALA are associated with a high morbidity and mortality and early diagnosis is important. To our knowledge only one previous case of a hepatoduodenal fistula complicating an ALA with radiological confirmation has been reported.


Calf vein anatomy and flow: implications for colour Doppler imaging. Early experience has suggested that colour flow Doppler ultrasound may have a diagnostic role in calf vein thrombosis. Before its accuracy within the calf can be adequately assessed, normal calf vein flow and anatomy needs to be understood. We, therefore, studied 40 normal volunteers, age range 24-75 years (mean 45.4), M:F 22:18, and assessed both flow and venous diameter in each of the three sets of calf veins in the supine and erect positions and once again in both these positions following the application of an above knee band. Paired sets of veins were present in all posterior tibial and common peroneal sets, but in only 85% of the anterior tibial group. Significant flow variations were present between different sets of veins, there being relatively less appreciable flow within the common peroneal (p < 0.05). Both band application and erect posture produced significant increases in venous diameter (p < 0.01, p < 0.001) in the posterior tibial and common peroneal veins, aiding visualization but at the cost of reducing flow following band application (p < 0.05, p < 0.01). The erect posture had no deleterious effect on calf vein flow. We, therefore, recommend that when the patency of calf veins is being assessed scanning should be performed in both a supine and erect position as this will help vein visualization without a reduction in flow, and thus avoid misinterpretation.


Ultrasound features of low power interstitial laser hyperthermia. Low power interstitial laser hyperthermia (ILH) is a reliable means of producing in situ thermal necrosis. Ultrasonic studies have been carried out of the changes that occur in canine liver during ILH performed at laparotomy. With a single fibre delivering Nd-YAG laser at 1-1.5 W for 670 s an hyperechoic region developed at the fibre tip measuring 5-6 mm in diameter; around this developed an area of hypoechoic change (up to 500s) giving a total area of changed echogenicity of 14-16 mm. With a multiple fibre system using 4 laser fibres simultaneously the sonographic changes were a summation of the changes seen with a single fibre, the hypoechoic areas overlapping. With this four fibre system the creation of large (3.5 x 2.8 cm) areas of thermal necrosis was possible. There was good correlation between the sonographic and pathological measurements of the region of thermal change. The sonographic studies showed the extension and overlap of regions of thermal necrosis and allowed visualization and accurate measurement of the area undergoing change. The same combined technique has been successfully applied in a small number of clinical cases and may be of use in the treatment of tumours in solid organs.


The potential use of diuresis Doppler sonography in PUJ obstruction. Three cases of proven PUJ (pelvi-ureteric junction) obstruction in whom duplex Doppler sonography was performed are described. In one case, there was a duplex transplant kidney with PUJ obstruction of the lower pole moiety. The resistive index of an interlobar lower pole artery was markedly elevated compared to that of an artery in the upper unobstructed moiety. In the other two cases, the resistive index of interlobar arteries of native kidneys increased significantly following intravenous frusemide simultaneous with an increase in the degree of pelvicalyceal dilatation. It is proposed that diuresis Doppler sonography may provide additional diagnostic information in patients with PUJ obstruction, and that the method warrants further evaluation.


Alveolar hydatid disease of the liver: computed tomography and transabdominal ultrasound with histopathological correlation. The appearances of alveolar hydatid disease of the liver (AHDL) on computed tomography (CT) and ultrasound (US) were retrospectively compared with histopathological appearances in 67 patients with 100 separate lesions. The radiological features were correlated directly with the pathological specimens obtained from each patient. We conclude that the CT appearances are more specific, but that US has a role to play in mass screening in endemic areas, and intraoperatively.


Transjugular intrahepatic portosystemic stent shunt (TIPSS): early clinical experience. Transjugular intrahepatic portosystemic stent shunt (TIPSS) is a new percutaneous technique for reducing portal venous pressure. We attempted TIPSS in six patients with recurrent bleeding for oesophageal or gastric varices between July 1991 and January 1992 with success in five. There have been no deaths. One patient re-bled after TIPSS. His portal pressure was found to be elevated persistently indicating an inadequate shunt. Following further dilatation of the shunt, portal pressure fell to a satisfactory level and bleeding has not recurred. No bleeding episodes have occurred in the other patients following successful TIPSS. Our series contributes to the growing body of experience which suggests that TIPSS is a safe and effective treatment for recurrent variceal bleeding.


Embolization with detachable balloons--applications outside the head. Detachable balloons, although widely used as an embolization material in neurovascular work, are rarely used outside the head. Yet they offer distinct advantages over other methods of embolization in certain situations. They can effect an instant and precise occlusion of large arteries and fistulae and unlike any other embolization technique the occlusion is reversible until the balloon is finally detached. In addition, they can be floated out to distal locations inaccessible with more conventional catheter techniques. They are inflated with contrast medium or silicone monomers. Large arteries and arteriovenous fistulae (AVFs) are best suited to balloon embolization where embolization distal to the fistula resulting in parenchymal infarction is not indicated. Thirteen patients underwent 14 detachable balloon embolizations. Eleven had large AVFs (4 coronary AVFs, 4 Blalock-Taussig shunts, 2 vertebro-vertebral fistulae and 1 renal AVF) and three had large arteries (2 aorto-pulmonary collaterals in one patient and 1 innominate artery pseudo-aneurysm). Twelve of these embolization procedures were successful and there were no complications. The two failures were due to inability to pass the balloon catheter around an acute angle in the introducer catheter and to early deflation. These cases illustrate a wide range of situations where balloon embolization may be used successfully. Continued refinement and improvement in the technique will allow expansion of the indications for non-neurological balloon embolization.


The current status of embolization in renal cell carcinoma--a survey of local and national practice. The current role of renal embolization in carcinoma of the kidney is uncertain. In order to assess surgeons' opinion of its usefulness a questionnaire was circulated to all general urologists practising in Britain and Ireland. Also, a series of cases in which the technique was employed (n = 35) was reviewed and compared with a similar group who were not embolized (n = 40). There was a 71% response to the survey. The principal findings were that all but five urologists believe that embolization should not be used routinely in the management of renal cell carcinoma. Thirty-five per cent stated that they felt it has a role in management of symptoms in metastatic or inoperable tumours. The review of both series of patients in our unit shows that embolization (using 95% ethanol infused via a balloon occlusion catheter) did not reduce peroperative blood loss and did significantly increase hospital stay. There were no deaths in this series, and morbidity was confined to 'post-embolization syndrome' in 16 cases. We believe that in those cases where embolization is indicated, alcohol infusion via a balloon occlusion catheter is a safe and efficient method.


MRI in diabetes insipidus due to metastatic breast carcinoma. Magnetic resonance imaging (MRI) has been established as a valuable imaging modality in the evaluation of pituitary disorders. We describe three women with known carcinoma of the breast, who presented acutely with biochemically proven diabetes insipidus (DI), in whom MRI was used as the primary investigative tool. The patients were studied using a 1.5T superconducting system, with gadolinium enhancement in two cases. All three had thickened pituitary stalks and two had complete loss of the normal high signal from the posterior lobe of the pituitary gland. Two also had enlargement of the anterior pituitary gland. One subject was also noted to have other metastases to the brain. All three had multiple secondary deposits elsewhere in the body and one had metastases to the clivus but without evidence of extension to the pituitary fossa. DI is uncommon in systemic cancers and anterior pituitary dysfunction much more so, due to the separate blood supply of the two lobes. Thickening of the stalk has not been found frequently in large autopsy series. In the clinical context of DI in a patient with a known primary tumour the loss of high signal from the posterior lobe and stalk thickening are indicative of infiltration by metastases. A pituitary mass or metastases to adjacent bones are not necessary for diagnosis.


The imaging characteristics of naso-sinus chondrosarcoma. Eighteen patients with histologically-verified naso-sinus chondrosarcomata are reviewed, emphasizing their CT and MRI appearances. These tumours present with a soft tissue mass expanding and destroying bone and typically (89%) showing areas of nodular or plaque-like calcification on CT. The magnetic resonance characteristics are more specific and when present with the typical CT features are diagnostic of chondrosarcoma. They combine high signal on T2-weighted sequences, with differential enhancement on post-Gadolinium T1-weighted scans. The contrast enhancement is seen at the periphery of the tumour and the central chondromatous core does not enhance. These changes are dependent upon the vascularity of the tissues concerned and have been correlated exactly with the histopathology of the resected tumour specimens.


Non-invasive assessment of the Circle of Willis using transcranial pulsed Doppler ultrasound with angiographic correlation. The ability of transcranial pulsed Doppler ultrasound (TCD) to provide a dynamic assessment of the functional capability of the Circle of Willis was assessed using conventional cerebral angiography for anatomic correlation. Eleven patients had normal four-vessel cerebral angiography prior to being investigated with ultrasound. Angiography and ultrasound both demonstrated a functional anterior communicating artery in nine of the eleven patients, giving complete agreement between the two techniques. Posterior communicating arteries were visualized angiographically in all eleven patients. Ultrasound identified bilateral functional vessels in nine, the other two patients having non-functional vessels. In these latter two patients, angiography demonstrated three of the four posterior communicating arteries to be hypoplastic and it was uncertain whether these vessels carried significant blood flow. The fourth posterior communicating artery was shown to have an absent proximal segment of the ipsilateral posterior cerebral artery, with a persistent fetal posterior communicating artery. This anatomical variation is a potential limitation of ultrasound for assessing functional posterior communicating arteries. These preliminary results indicate that a combination of the anatomical (angiographic) and dynamic (ultrasonic) data may prove to be complementary for assessing the Circle of Willis.


Colour flow imaging of calf vein thrombosis. Ultrasound and more recently colour Doppler ultrasound has been successfully used in the diagnosis of lower limb venous occlusive disease. Colour Doppler ultrasound has shown promise in the diagnosis of calf vein thrombosis but to date there has been no prospective trial to specifically evaluate its potential. In view of this, we carried out a prospective trial of 50 patients comparing the accuracy of colour Doppler ultrasound with venography in the diagnosis of deep venous thrombosis both above and below knee but in particular with respect to the detection of calf vein clot. Of the 50 patients studied, 10 had only one imaging modality performed as there were eight venographic failures and two ultrasonic failures. Comparison was only thus possible in 40 cases. As in previous studies, colour Doppler ultrasound was shown to be accurate in the diagnosis of thrombosis within the femoro-popliteal veins and had a sensitivity and specificity of 100% respectively. With respect to calf vein lesions, there was one false negative scan using the ultrasonic technique giving a sensitivity of 95%, specificity of 100% and accuracy of 97.5%. We feel colour Doppler ultrasound can and should be used as a first line alternative to venography and can be employed for the exclusion of both above and below knee deep venous thrombosis. Venography should now be reserved for those patients who are unsuitable for ultrasound examination or who have an equivocal ultrasound scan.


Case report: life-threatening hypercalcaemia secondary to pancreatic tumour secreting parathyroid hormone-related protein--successful control by hepatic arterial embolization. Parathyroid hormone-related protein elaborated by pancreatic neuro-endocrine tumours can cause life-threatening hypercalcaemia. This is the first reported case where hypercalcaemia caused by such a tumour has been successfully controlled by hepatic arterial embolization.


Case report: congenital mediastinal arteriovenous fistula in an adult--diagnosis with digital subtraction angiography. A case of asymptomatic congenital mediastinal arteriovenous fistula detected in an adult patient is presented. The diagnosis was suspected clinically and confirmed with intravenous digital subtraction angiography. The clinical and radiological features are discussed and the literature reviewed.


Case report: volvulus of a mesenteric cyst--an unusual complication diagnosed by CT. A 10-year-old girl presented with colicky abdominal pain and a vague left sided mass on physical examination. Plain radiographs of the abdomen were unremarkable but ultrasound examination demonstrated a large right sided unilocular cystic abdominal mass. Computed tomographic features were diagnostic of volvulus of the proximal small bowel with associated mesenteric cyst. Surgery confirmed CT findings and no mid gut malrotation was noted at operation.


Case report: the vanishing ring sign--an unusual CT manifestation of multiple sclerosis. Ring-like computed tomographic (CT) enhancement of a solitary cerebral mass usually indicates neoplasm or abscess. A 64-year-old man with this sign was found to have multiple sclerosis (MS), and following oral steroid treatment, it disappeared.


Case report: inverted contrast medium--urine level in the bladder on computed tomography. Fluid-fluid levels within structures are caused by differences between the specific gravity of the fluids. This results in a characteristic appearance on computed tomography (CT), with urine which contains contrast medium and has a high specific gravity layering posteriorly in the dependent portion of the bladder, while lower specific gravity, non-opacified urine is found uppermost. We report a patient in whom the contrast medium-urine level was inverted because of sediment in the dependent part of the bladder.


Gravitational stress and volume regulation. During the past 3 decades, groundbased experiments have been performed in order to investigate the effects of increased and decreased gravitational stress, respectively, on the renal response in humans. Experiments that simulate an increase in gravitational load (+Gz) to the subjects (centrifugation, passive head-up titlt [HUT] or lower body negative pressure [LBNP] have clearly demonstrated a decrease in renal sodium and water excretion. Simultaneously, increases in plasma levels of arginine vasopressin (AVP), renin activity (PRA), aldosterone (PA), norepinephrine (NE) and decreases in ANP have been observed. Additionally, experiments that have utilized immersion of seated subjects to simulate a decreased gravitational stress (approximately 0 Gz) have demonstrated that renal water and sodium excretion increases by 100-400% and that plasma AVP, PRA, PA, and NE concentrations are reduced and ANP levels increased. Alternative experimental models conducted to simulate the effects of weightlessness in humans such as head-down tilt (HDT) and lower body positive pressure (LBPP) have yielded less consistent results than those of water immersion (WI) with respect to renal function. However, compared to a seated control HDT clearly induces an increased rate of renal fluid and sodium excretion. The demonstration that central volume expansion during WI is accompanied by an increase in renal fluid and electrolyte excretion and that central hypovolaemia during centrifugation, HUT, and LBNP is accompanied by the opposite effects indicate that changes in central blood volume is an important determinant of the renal functional changes. Results of experiments in humans during weightlessness in space are inconsistent and difficult to interpret. However, they have indicated that a cephalad redistribution of blood and fluid occurs and that this is accompanied by a decrease in total body fluid. Experimental models that, respectively, increase and decrease the gravitational stress in humans constitute promising tools in the investigation of the physiology and pathophysiology of volume regulation.


Changes in autonomic cardiovascular control in mid-pregnancy. Spectral analysis of heart rate variability was used to study autonomic nervous control in mid-pregnancy. Fifty women (age 22-36 years) with singleton pregnancies (mean duration of gestation 27.7 weeks) and 39 non-pregnant female controls (age 21-39 years) were studied using controlled breathing and orthostatic tests. During spontaneous breathing the overall heart rate variability was lower in pregnant subjects indicating a decreased parasympathetic tone at rest. The decreased parasympathetic tone probably counts for the increased heart rate in pregnancy. The parasympathetic efferent capacity of autonomic cardiac control was found to be similar in pregnant and non-pregnant subjects, as no difference was seen during controlled breathing in periodic heart rate variability between the groups. Standing up caused a similar change in low frequency and mid-frequency bands in both groups, but high frequency heart rate variability increased in pregnant subjects and decreased in the controls indicating an increased sympathetic tone at rest in mid-pregnancy.