[Esophageal replacement with lyophilized dura (author's transl)].

In 50 dogs thoracic or cervical esophagus was resected and the defect was replaced by a prosthesis made out of lyophilized dura. The healing process was studied radiologically and by clinical and histological examination. The experiments have proved the feasibility of bridging esophageal defects with lyophilized dura. The dura is replaced within 2 months by a tube of connective tissue. Until epithelialisation is complete there is a tendency to circular contraction. A stenosis could be prevented by dilatation or by means of a homologous-alloplastic esophageal prosthesis.


Posterior table fractures of the frontal sinus: I. An experimental study.

Experiments using cats were performed to examine the natural history of posterior table fractures of the frontal sinus and the methods available for treatment. Elevation of depressed fractures and obliteration by either fat or osteoneogenesis and fibrosis were the modalities of treatment used. Comparisons were made with untreated controls. Fascia reinforcement of the dura and plugging of the nasofrontal duct were variables. The nasofrontal duct is critical in the natural history of these injuries. All fractures of the posterior table heal if drainage into the nose is maintained. Fractures which are elevated heal by bony union with associated mucosal and dural healing. Loose fragments of the posterior table heal if left in place. Mucoceles form if the nasofrontal duct is obstructed, if mucosa is inadequately removed during obliteration and, in some instances, where islands of mucosa are isolated by mucosal laceration. Viable adipose tissue in the sinus prevents significant ingrowth of mucosa from the nasofrontal duct. Growth of mucosa into fracture lines was not a problem. Both adipose transplants and intrasinus fascia reinforcement appeared to contribute to well defined posterior table healing.


Alternative uses for the flexible fiberoptic bronchoscope in otolaryngology.

Currently there are many fiberoptic instruments available to the otolaryngologist. These include, in addition to the rigid endoscopes, the fiberoptic headlight, cable, indirect laryngoscope, nasopharyngoscope, flexible laryngoscope, flexible esophagoscope and flexible bronchoscope. Each possesses a certain unique characteristic to aid the otolaryngologist. For several of these, there are certain alternative uses. The purpose of this report is to discuss additional uses for the flexible fiberoptic bronchoscope in relation to the head and neck as it is the most versatile instrument.


Theory of hearing--cellular approach.

A model was developed to simulate the combination of Davis's electrical model of cochlear excitation and the electrical model of a neuron; both afferent and efferent fibers were included. The resulting model was stimulated by varying the hair cell resistance. This is equivalent to varying the sound pressure level presented to the cochlea in the physiological system. It was found that, in the normal ear, there was a critical level of hair cell resistance below which no firings were obtained (no information transmitted). The scala media potential was varied and the previous tests repeated. This was done to simulate changes in the stria vascularis of the physiological system. It was found that as the scala media potential decreased, the critical value of the hair cell resistance increased. Two clinical procedures are proposed: the first is a procedure to improve hearing for persons with a "linear or flat loss"; the second is a procedure for improving the hearing for persons with a "ski slope loss."


Diagnosis and management of cochlear hydrops.

In an early case of cochlear hydrops, the symptoms of a mild pressure sensation or fullness in the involved ear may be mistaken for a blocked eustachian tube. More severe cases demonstrate a true sensori-neutral hearing loss that fluctuates. Tinnitis is usually present during the attack and will often subside when the hearing returns to normal. The neurotologic evaluation is negative and attempts to establish an etiology are seldom fruitful. The treatment is usually medical, and empirically, these individuals are treated with diuretics, low salt diet, and vasodilators. It is felt by most investigators that cochlear hydrops is an early form of Ménière's disease, and over a long period of time these individuals may develop vertigo as a complaint. The purpose of this paper is to discuss this interesting form of Ménière's disease in detail concerning etiology, physiology, diagnosis, and treatment. A small series of patients who have undergone the subarachnoid endolymphatic sac procedure will be reported according to the guidelines set forth by the Committee on Hearing and Equilibrium of the American Academy of Ophthalmology and Otolaryngology. Based on the result in these patients, it would appear that this procedure should be considered in those individuals who are refractory to medical management. There is convincing evidence that the shunt does stabilize the hearing in many instances.


Preliminary results with use of an eustachian tube prosthesis.

One of the primary causes of tympanoplasty failure is inadequate eustachian tubal function. Measures taken to improve tubal function have often been inadequate for their task. A prosthesis was constructed for the purpose of installation at the time of tympanoplasty to improve eustachian tubal function. Our early results with a two to 14-month follow-up of 38 patients show a success rate of 79 percent in secruing an aerated middle ear space in ears which were judged to have poor eustachian tubal function.


A clinical and anatomical study of the various techniques of irrigation of the maxillary sinus.

Irrigation of the maxillary sinus is a common procedure in clinical practice for removing the contents of the antrum for either diagnosis or therapy. For many years, it has been accomplished by inserting a trocar in either the natural ostium or the medial wall of the sinus under the inferior turbinate. Recently, the anterior wall of the maxillary sinus has been re-introduced as a better route. It is more direct and is the only one suited for use in a child whose sinus is underdeveloped. The anterior route has been termed the canine fossa technique and is the preferred route since it has a high degree of patient acceptance and safety and can be done easily and quickly by the clinician through a familiar anatomical pathway.


Residual carcinoma of the larynx.

Two hundred forty-nine patients with squamous cell carcinoma seen and treated at Universtiy of Wisconsin Hospitals from 1960-1972 were analyzed as to recurrence rates, with emphasis on specific sites of recurrence, salvage rates, and end results. Each case was carefully staged according to the TNM classification as set forth by the American Joint Committee for Cancer Staging and End Results Reporting (Revised, 1972). Of the cases treated initially with radiation, 58 percent developed recurrences in the larynx, and 5 percent developed surgical lymph node metastases. Of the cases treated initially by surgery, 13 percent demonstrated local recurrences and 15 percent cervical lymph node metastases. Twenty-six of 86 initial therapy failures were salvaged with further treatment, giving a salvage rate of only 29 percent. The overall recurrence free rates, including cases salvaged, were T1, 91 percent; T2, 86 percent; T3, 68 percent; and T4, 44 percent.


Tympanic membrane keratoma (cholesteatoma) in children with no prior otologic surgery.

Three children whose eardrums appeared normal upon previous examinations, one with the otomicroscope, apparently developed tympanic membrane cholesteatomas that penetrated the fibrous layer of the pars tensa. Their histories all included episodes of acute otitis media, but no otorrhea. No otologic surgical procedures, including myringotomy, had been performed. These cases are thought to provide clinical support for the basal epithelial migration theory of cholesteatoma genesis. Rüedi's experiments suggest that cholesteatomas resulting from basal epithelial migration may not be visible for 18 to 30 days; thus, follow-up evaluations after acute otitis media should probably include examinations one and two months after the infection. Pediatricians and family physicians should be urged to seek otologic consultation for patients with even minor eardrum abnormalities, particularly those following infection.


"Practical suggestions on facial plastic surgery--how I do it". Sublabial mucosal flap: repair of septal perforations.

The majority of perforations of the nasal septum, regardless of etiology, create little more than an annoyance to the patient. Perforations commonly may be totally asymptomatic, discovered only on careful nasal examination. It is reasonable to assume, therefore, that only those septal defects creating important symptoms are deserving of repair and correction. Heavy crusting, recalcitrant bleeding and impending or actual loss of dorsal support are justifications for perforation closure. Textbooks and journals abound with suggested varieties of techniques of repair, testifying to the non-effectiveness of any one suitable approach. Local mucosal flaps, turbinate flaps, pedicle skin flaps, and free grafts of skin, dermis, perichondrium, cartilage, and fascia have all been employed with variable results. An inadequate blood supply and unfavorable scarred host bed commonly lead to failure of the above reconstruction methods. In the past five years a horizontal mucosal flap derived from the undersurface of the upper lip has proved reliable and expedient in septal perforation re-epithelialization and closure. The reconstructive procedure is not technically difficult and leads to minimal patient discomfort.


A study of nasal airway function in the postoperative period of nasal surgery.

One hundred fifty-seven consecutive nasal surgery cases were followed for a minimum of one year or more. Ten cases were considered to have unsatisfactory mechanical airways, caused either by return of the original pathology (alar collapse or atrophic rhinitis) or by inadequate mechanical results. Nineteen cases in which the mechanical airways were satisfactory had soft tissue obstruction secondary to chronic inferior turbinate congestion. The effects of nasal allergy and the trauma of postnasal packing on chronic congestion of the turbinates are tabulated according to the type of surgery performed and results discussed.


Surgical repair of the caudal end of the septum.

The repair of the caudal end of a severely deviated septum has been a challenge since the beginning of septum surgery. In the time of Freer and Killian, a caudal and dorsal strip was always left. Frequently, the most obvious portion of the septal deformity, the caudal end, was undisturbed and the deformity persisted. Metzenbaum, Fomon and Cottle procedures designed to correct this problem. The procedure described in this presentation utilizes the maxilla-premaxillary approach to the septum. The laporotomy of the rhinoplasty procedure is used to expose the upper lateral cartilages. These cartilages are submucously uncovered and separated from the dorsal margin of the septal cartilage. This provides complete exposure of the line of fracture usually responsible for the extreme deflection of the caudal end of the septal cartilage. A strip of cartilage including the line of fracture is removed. The caudal end is attached to the mucoperichondrium of the right side and now is completely mobile. The caudal end is placed over the maxillary spine and sutured in position by a chromic cat gut suture from the prespine fascia through the caudal edge of the septal cartilage. The upper lateral cartilages are sutured to the dorsal margin of the septum acting as a splint to hold the sections of cartilage straight and immobile until the tissues heal.


Carcinoma in situ of the larynx.

A retrospective study of carcinoma in situ of the larynx at the British Columbia Cancer Institute indicates that radiotherapy, using a tumoricidal dose of Co 60, is the treatment of choice for this condition. Between 1940 and 1972, 43 patients with carcinoma in situ of the vocal cords were seen. A follow-up of five years or more was possible in 28 of these cases. Twenty-two were treated primarily with a tumoricidal dose of radiotherapy. Twenty-one of the 22 were free of disease for at least five years. This study, therefore, shows a five-year cure rate of almost 100 percent for patients treated with radiotherapy. It also brings out two further points regarding carcinoma in situ of the larynx; namely, an apparent increase in its incidence, and the presence of co-existing invasive carcinoma in some cases. We feel that since the incidence of laryngeal carcinoma has not increased, this apparent increase probably represents a greater awareness by both the pathologist and the clinician. We have also achieved more accurate diagnosis since the introduction of routine microlaryngoscopy. The single radiotherapy failure in our series was due to failure to diagnose co-existing invasive carcinoma. This would seem to be the most likely cause of similar failures reported in the literature.


Surgical management of airway obstructions during sleep.

Anatomical or physiological airway obstructions during sleep, of which the patient is unaware, cause daytime sleepiness at first, then signs of decreasing mental function, and eventually in some individuals, pulmonary and systemic hypertension. A few of these patients had been recognized before, the Pickwickian syndrome and in children with cardiac problems and large tonsils. The majority, however, present as sleep disorders. This paper describes our surgical experience with improving the airways of 19 children and adults with daytime somnolence.


Glottic and subglottic stenosis from endotracheal intubation.

As a result of increased use of prolonged endotracheal intubation, complications of intubation are now being seen more often. Stenosis of the airway may develop at the level of the glottic or subglottic larynx, or in the trachea. Discussions of management do not always distinguish clearly between laryngeal stenosis and tracheal stenosis. Yet, these are two separate entities. Discussions of laryngeal stenosis usually deal with subglottic stenosis, with less emphasis on obstruction at the glottic level. Of 20 patients, 14 adults and six children, with stenosis of the larynx secondary to intubation, we were successful in establishing adequate airways in 16. An analysis of these 20 patients leads to the following conclusions: 1. Scarring in the glottic posterior commissure between the arytenoid cartilages is a frequent cause of laryngeal stenosis after intubation. 2. Endoscopic management can be successful in many cases if it is started early enough, and repeated as often as is necessary. The earlier it is begun, the better the results will be. 3. Indwelling stents which are extremely valuable in laryngeal stenosis from external trauma, may not be as useful in stenosis from endotracheal tube trauma.


Mucormycosis.

Three cases of mucormycosis are presented; two with unusual aspects: one with previously unreported involvement of the mandible, and one presenting as a cavernous sinus thrombosis. Review of the literature reveals a limited number of survivors. Survival in two of the cases presented here suggests that early diagnosis, aggressive therapy with surgery, and amphotericin B should improve the prognosis.


Spontaneous and traumatic perilymph fistulas.

Clinicians have been aware of the problem of post-stapedectomy perilymph fistulas for some time. The existence of non-surgical oval and round window fistulas has been known and was first described in detail by Fee in 1968. This paper concerns a small series of patients with spontaneous and traumatic perilymph fistulas. Five oval window fistulas and one round window fistula are reported. Clinical features, audiometric, radiographic and vestibular findings are discussed. The etiology of traumatic and spontaneous fistulas is not well understood, but seems to bear a relationship to sudden increased in intracranial pressure transmitted to the inner ear through the cochlear aqueduct. Middle ear pressure changes, as seen in acoustic or barotrauma, may also cause these leaks. Indications for surgery and techniques of perilymph fistula identification and repair are discussed in the paper. Surgical correction led to relief of vertigo in 80 percent of patients in this series, and significant hearing improvements were seen in 50 percent of the patients. In evaluating patients with sudden sensori-neural hearing loss, or persistent vestibular symptoms following head or ear trauma, the otologist should keep in mind the possibility of a perilymph fistula and actively investigate these patients. Evidence presented in this paper and in the literature suggest that identification and correction of spontaneous and traumatic perilymph fistulas can lead to resolution of vestibular symptoms and improved hearing in a significant number of patients with these lesions.


Surgical and nonsurgical management of facial paralysis following closed head injury.

The outcomes of facial nerve decompression, surgical exploration, and nonsurgical treatment for facial paralysis following closed head injury were analyzed in 30 patients with an intact facial nerve, and complete evaluation. Objective evaluation of outcome was achieved by calculation of a Facial Paralysis Recovery Profile and Recovery Index (Profile minus complications). Twelve of 15 patients with incomplete facial paralysis were treated medically. All followed patients with incomplete paralysis and bilaterally equal facial nerve excitability had a Recovery Index of + 10 (complete recovery of function, no complications). Three with partial denervation had a Recovery Profile of + 10 with mild contracture and synkinesis. The average Recovery Profiles for all patients treated by decompression, exploration, or nonsurgically were respectively 4.0, 5.7, and 5.7. The Recovery Indices were +1.8, +3, and +2.7, respectively. Where nerve excitability had become abnormal, facial nerve decompression was of no benefit in traumatic facial paralysis due to closed head injury. Nerve excitability tests of peripheral branches are of great value for prognosis and selection of patients who do not need surgical intervention. Substitution of facial nerve exploration for facial nerve decompression seems reasonable. Polytomography of the facial canal is invaluable in selection of patients for operation.


Frontal sinus trauma: experimental reconstruction with proplast.

Trauma has become the most common pathologic entity requiring operative intervention in the frontal sinus. Treatment has evolved from simple open drainage to ablation with reconstruction at a later date. Methyl-methacrylate, currently the most widely used alloplastic material, has inherent disadvantages such as two-stage reconstruction, difficulty in handling and molding, and susceptibility to trauma. The present investigation evaluates Proplast, a biocompatible Teflon fluorocarbon polymer implant, in one and two-stage frontal reconstruction following traumatic defects to the canine frontal sinus. Following the loss of anterior or posterior frontal bone, Proplast provided excellent cosmetic reconstruction over a period of one year. Resistance to infection was good, reaction with dura and brain was absent, and cerebrospinal fluid leaks sealed rapidly. In contrast to other alloplastic materials, rapid vascularization and collagen ingrowth lead to stabilization rather than sequestration. Several advantages over alloplastic and metallic implants may give Proplast a unique potential in operative cranioplasty.


Contribution to therapy of dysphonia plica ventricularis.

Excision of the hypertrophic ventricular folds was performed in 35 patients by means of laryngomicroscopy. In most of our patients this therapy promptly resulted in a clear voice. Correlating the laryngomicroscopic finding and the histological picture we were able to classify hypertrophy of the ventricular folds into three stages, each of which presents with a characteristical clinical and histological picture and thus requires approapriate therapy. In Stage I the histological changes are reversible and conservative phoniatric therapy leads to success relatively quickly. In the second stage histological changes may also be reversible, and the prolonged and persistent phoniatric therapy leads to success but we prefer microsurgical excision because of the direct effect. In Stage III, however, we found irreversible histological changes in the sense of connective hyperplasia which prompted us to conclude that microsurgical excision alone may lead to regression of the hoarseness.


Effect of radiation therapy on facial nerve cable autografts.

Facial nerve cable autografts were performed on 20 cats with 10 animals receiving 6,000 Rads of postoperative irradiation over six weeks. Testing by clinical appearance, pontograms, and axon counts showed no statistical difference in the operated only and the operated plus irradiated groups. Pontograms illustrated the clinical observance of spasticity, delay and weakness often seen after grafting. This animal work tends to verify the clinical impression that in patients requiring postoperative irradiation for a malignancy necessitating excision and grafting of the facial nerve, anticipated results should be equivalent to the facial nerve cable autografts without postoperative irradiation.


Necrotizing sialometaplasia involving the nasal cavity.

Necrotizing sialometaplasia is a disease process which affects minor salivary glands. It may clinically and microscopically resemble squamous cell or mucoepidermoid carcinoma but is histologically benign. Thirteen patients with this process occurring on the hard palate have been reported in the past two years. We describe two cases in the nasal cavity and propose that compromise of the blood supply contributed to the occurrence of these lesions. This apparently benign lesion may represent nonspecific reaction of salivary and mucous glands to ischemic injury and must be distinguished from carcinoma.


"Practical suggestions on facial plastic surgery--how i do it"; subcutaneous pedicle flap reconstruction of lower nasal defects.

Large defects of the thick, immobile lower nasal skin are most optimally reconstructed by use of the single stage, reliable and cosmetically acceptable subcutaneous pedicle flap. Skin incisions are minimized and are easily placed in natural skin lines. The donor defect is closed directly. Grafts, other local flaps or regional flaps present the disadvantages of less ideal color or contour match, reduced flap mobility, restricted available skin, additional or more obvious donor site scarring or distortion, or unnecessary complexity.


Two hundred laryngeal cancers: patterns of growth and spread as seen in serial section.

Whole organ serial section studies of specimens removed by partial or total laryngectomy have yielded information which the surgeon ordinarily needs in determining the suitability of the laryngeal cancer for conservation surgery. This information includes the degree to which the surface presentation of a growth reveals its margins, and the likelihood of invasion of the laryngeal framework and overlying soft tissues. The present studies indicate that in assessing these features of a growth before treatment, the surgeon can be guided by: 1. location; 2. fixation, and 3. size of the growth. These features are presented together under each location.


Effect of inflammation of the ventilatory function of the eustachian tube.

In an attempt to determine the effect of an upper respiratory tract infection on the ventilatory function of the Eustachian tube, 20 children who had recurrent acute or chronic middle ear effusions were studied. Baseline Eustachian tube function testing was obtained when there were no signs or symptoms of upper respiratory infection. These tests were repeated at six-week intervals and whenever an upper respiratory tract infection supervened.


Experiences with type IV tympanomastoidectomy.

Tye IV tympanoplasty was performed on 72 patients having advanced suppurative disease of the middle ear and mastoid with total loss of the middle ear sound transmission system. The principal features of the method consist of a postauricular wide-field mastoidectomy, canalplasty, meatoplasty, Type IV tympanoplasty with cutaneous exteriorization of the footplate and mastoid obliteration. The method achieved a postoperative bone-air gap of 30 db or less in 59 percent of cases with a 15 percent incidence of recrudescence requiring some further surgery.


Middle fossa vestibular nerve section in the management of Ménière's disease.

The triad of fluctuating hearing loss, tinnitus, and episodic attacks of vertigo known as Ménière's disease can be a frustrating therapeutic problem. While most patients respond to a medical regime consisting of a low salt diet, diuretics, diazepam, and propantheline bromide, there is a significant group who remain refractory to conservative management. These individuals either continue to experience their distressing symptoms or undergo some type of surgical procedure in an attempt to seek relief. There are a multitude of such techniques available to the otologic surgeon and he must make the decision as to which procedure is best for any given individual. The authors' employ three surgical approaches for the management of Ménire's disease. These are the translabyrinthine labyrinthectomy, the endolymphatic subarachnoid shunt, and the middle fossa vestibular nerve section. In this paper the indications for surgery, technique, results and complications are covered in detail. Thirty-one patients are reviewed who have been followed from one to four years postoperatively. Seventeen had total and 14 had superior vestibular nerve sections. The results were much better in the total group, as 94 percent had complete relief of vertigo and 76 percent were able to maintain their preoperative hearing level. The authors feel the middle fossa vestibular nerve section is a valuable addition to the otologist's armamentarium in the treatment of the patient who is refractory to medical management.


Indications for surgery in Mé Niére's disease.

Ménière's disease has been shown to have multiple causes, each of which requires a specific treatment. Patients who do not respond to medical treatment often are allowed to suffer prolonged disability from their symptoms or develop permanent hearing loss without the benefit of surgery. The physician's uncertainty regarding which patient will ultimately respond to medical treatment or have spontaneous remission of symptoms can cause a delay in what would otherwise have been definitive surgical treatment which would have allowed the patient to return to a happy and productive life. A careful analysis of 120 patients studied intensively for five years has shown that patients who exhibit specific characteristics and diagnostic findings will ultimately require surgery for control and relief of their symptoms, while others can be expected to recover with medical treatment. Fifty-six of the 120 patients ultimately required surgery to rid them of their symptoms. These patients were almost exclusively of the group considered to be idiopathic, viral, small internal auditory canal syndrome, or caused by physical or acoustic trauma. Those patients who had other causes for their Ménère's disease rarely required surgical treatment and were well controlled by specific medical therapy. These observations would seem to provide us with information which would allow patients who might be reasonably stages of their disease where conservative measures can more often be expected to give complete relief with preservation of hearing. The indications for surgery in patients with Ménière's disease based on this information will be reviewed. The use of this knowledge has significantly reduced the morbiditiy associated with Ménière's disease.


The case for elective prophylactic neck dissection.

The possibility of improving the cure rate of cancer of the head and neck by radical neck dissection of the clinically negative neck (elective neck dissection) continues to pose a therapeutic dilemma. This paper seeks to review the available information, analyze relevant aspects of the issue and attempt to draw conclusions which will be helpful both to physicians and their patients. The discussion is confined to squamous carcinoma of the larynx, pharynx, and oral cavity.


Description of a new device: an intranasal airway/splint.

Over the past two decades, the concept and practice of using septal splints has gained in popularity. Various methods have been used including X-ray film, sheets of Teflon and strips of Polyethylene. In this presentation a new device is introduced which incorporates the principles of septal splinting, along with the simultaneous use of nasal breathing tubes. A brief history of septal surgery and splinting is discussed, and the new device is described, both in its configuration and usage.


Influence of Caldwell-Luc operation on developing permanent teeth.

The influence of Caldwell-Luc operation on the permanent teeth of school children was studied in a material of 21 six to 14-year-old children, who had undergone, altogether, 30 Caldwell-Luc operations. Ten of the children had also undergone 23 endonasal antrostomies. The control material consisted of a class of 27 healthy school children, their mean age being 10.2 years. Total anesthesia was found in five teeth on the operated side and in one tooth on the non-operated side. Additionally, the operation had caused slight hypesthesia in part of the teeth, mostly in the first incisors. All sensory disturbances were caused by nerve lesion only, and no tooth had died as a result of the operation. The operation could not be shown to be conducive to caries. Correctly performed, Caldwell-Luc operation does not cause serious dental injuries in school children, and is indicated especially in chronic sinobronchitis when conservative methods of treatment fail.


Use of enzymes for meat impactions in the esophagus.

A case is reported in which papain was satisfactorily used to treat a patient who had meat impacted in his esophagus. The English literature pertaining to the usage of proteolytic enzymes in treating esophageal meat impaction is reviewed. (Two perforations and deaths have been reported in association with the usage of this technique. Ninety instances of employment of the technique were reported in the literature. The method has doubtlessly been used in numerous unreported instances. At present it is unrealistic to conclude that the method is safer or more dangerous than routine endoscopic removal of impacted meat. Several conclusions may be drawn: 1. Enzymes should not be used if the physician has any reason to suspect that a bone may be lurking within the impacted meat. 2. Best results using any enzyme will be obtained if pooled secretions above the impacted meat are first removed with a nasogastric tube. The enzyme solution may also be administered through the nasogastric tube when the physician is certain of the tube's position. 3. Extreme caution is mandatory during esophagoscopy for removal of a meat impaction after unsuccessful employment of enzymes. Removal of pooled enzyme in the esophagus should be attempted prior to doing esophagoscopy on impacted meat persisting after a course of enzymatic treatment. We would advocate nasogastric tube suctioning, and possibly even esophageal lavage for this purpose. 4 A contrast study of the esophagus should be done after any meat impaction has occurred to rule out otherwise silent esophageal pathology which may have precipitated the impaction.


[Electron microscopic study of the small intestine in intestinal lymphangiectasia and constrictive pericarditis (author's transl)].

Electron microscopic study of the small intestine in cases of intestinal lymphangiectasia and in cases of constrictive pericarditis was performed. This study revealed that numerous chylomicron-like particles are present in the lymphatic lumina, in the extracellular spaces of the lamina propria, and within the interepithelial spaces between the absorptive cells. Presence of chylomicron-like particles in the intestinal lumen suggested possibility of passage of these substances into the intestinal tract through the interepithelial spaces. Similar findings to those as seen in intestinal lymphangiectasia were observed in constrictive pericarditis. A few pseudopode-like cytoplasmic projections of the undifferentiated crypt cells were noted. Other mechanisms of enteric protein loss are postulated.


[Etiology and management of habitual constipation (author's transl)].

Habitual constipation is present, if defecation occurs because of prolonged retention of stool in the colon less than three times per week. Motility of the intestine is increased in these cases, not decreased as has been thought for long time. Several factors of modern civilization favor habitual constipation, e.g. nutrition devoided of poorly digestible ingredients, and lack of physical exercise. The diagnosis of habitual constipation should only be made after careful exclusion of all organic causes by means of x-ray and endoscopic examination. Therapy is conservative in most cases. The diet ought to be rich in indigestible ingredients; eating and defecation habits have to be adapted to a regular pattern. Hydrophilic colloid laxatives may be used as well as in a limited extent laxatives effective on an osmotic basis. Laxatives acting more drastically or being effective upon contact with the intestinal mucosa are not suited for long-term therapy of constipation. Surgery is indicated only in a few cases.


[Screening for colorectal cancer with the Haemoccult test (author's transl)].

Results are reported of a 5 year trial with the Haemoccult stool-test in a diagnostic center (DKD), and of a 1 year trial in the offices of 110 physicians. In the DKD 8 000 patients were tested: In a non-selected group 2,4% and in a selected one 3,8% of tests performed turned out to be positive; the diagnosis of carcinoma of the colon or rectum was established in 32 of these cases and 45 large polyps were traced. In most of the offices the test was positive in less than 3% of the patients tested, 57 of these patients had a carcinoma and 26 polyps. In 54 of all 89 cases with carcinoma and in 46 out of 71 polyps the lesions could not be found by digital or rectoscopic examination, due to a higher localization; 17 of the cancer patients were asymptomatic except for a positive Haemoccult test. Using only 3 tests per patients, 7 out of 96 colorectal cancers and 27 out of 98 large polyps were negative. 6 haemoccult tests to be done on three successive stools (as originally proposed by Greegor) are recommended as a yearly routine procedure in all persons about 40 years of age for early detection of carcinoma or polyps of the colon.


[Congenital giant diverticulum of the descending colon (author's transl)].

At the autopsy of an 80 years old women an about 60 cm long vermiform deverticulum of the colon was detected originating immediately distal from the left colic flexure and running retroperitoneally downnard versus the promontorium. On the basis of topography, histology and length this structure was interpreted as a congenital traction deverticulum.


[Differential diagnosis of tumors of the duodenal bulb by endoscopy and biopsy (author's transl)].

Duodenoscopy was performed in 2 602 patients; malignant tumors were found in 5, hyperplasia of Brunner's glands in 5, hyperplasia of lymphatic follicles in 26, inflammatory pseudo-polyps in 9, and ectopic gastric mucosa in 5 cases. Only 3 of the big tumors had been detected by x-ray examinations; enlarged lymphatic follicles and the polyps had escaped x-ray detection altogether. Infiltration of the mucosa by tumor tissue can be suspected merely on the ground of endoscopic inspection with a high degree of probability. Histological diagnosis depends on forceps biopsy. Big particle biopsy of submucosal tumors with a sling carries a high risk, which however has to be taken in order to obtain a definite diagnosis. Tumors of the duodenal bulb caused by inflammatory processes do present considerable diagnostic problems. Special problems of diagnosis and therapy of the cases presenting with hyperplasia or adenoma of Brunner's glands are discussed in a special section.


[Duodenal xanthofibrogranuloma (author's transl)].

A 56 years old woman presented with nonspecific epigastric pains and anemia. X-rays of the upper gastrointestinal tract demonstrated a tumor of the duodenum, which was removed surgically. The histologic examination showed a xanthofibrogranuloma (XFG). To our knowledge, this is the first XFG found in the duodenum. Morphological and clinical findings as well as diagnosis of this condition are briefly described and the pertinent litreature is reviewed.


[Glandular cysts of gastric mucosa, a new gastroenterological entity (author's transl)].

Two cases are reported with polypoid changes of the corpus mucosa of the stomach. X-ray and endoscopic diagnosis was: gastric polyposis. On histological examination cystic changes of the mucosal glands could be detected. These cases were followed up for 7 years; no change occurred during this period until finally the "polyps" disappeared. Localization in the corpus area and easiness of endoscopic polypectomy, as well as the cystic pattern of the mucosa are typical for these "glandular cysts". This condition was unknown up to now or was not diagnosed correctly, this entity not having been delineated yet nosologically.


[Glandular cysts of the gastric mucosa. Diagnosis and a pathogenetic hypothesis (author's transl)].

Gastric polyposis was diagnosed in a 61 year old woman. Cystic deformations of the gastric glands were found on histological examination. These changes cannot be classified according to the generally accepted scheme of classification of epithelial gastric polyps. During X-ray studies a definite enlargement of the polyps could be observed under maximal stimulation with pentagastrin.


Thermography in breast cancer screening: progress and prospects.

The use of thermography in breast cancer detection is reviewed. Although advantageous in its total lack of radiation exposure to the patient, thermography has limitations in that significant false-positive and false-negative cancer detection rates have been demonstrated. The potential use of thermography in evaluation of the pathogenesis of breast cancer and in identifying women at high risk is discussed.


Management considerations in medical equipment acquisition.

Financing acquisition of sophisticated instrumentation and accessory equipment may best be accomplished by leasing, which conserves working capital and borrowing capacity. A flexible leasing agreement allows for changing conditions, such as purchasing necessary instrumentation not previously anticipated. However, before agreeing to lease, the potential lessee should investigate the lessor's reputation and financial strength.


Measuring cervical dilatation in human parturition using the Hall effect.

An instrument was developed to continuously measure cervical dilatation in human labor. The instrument utilizes a small magnetic field source, which is attached to one edge of the cervix while a magnetic field sensor is attached to the diametrically opposite edge of the cervix. The sensor, using two Hall generators, measures orthogonal components of the field to minimize the effects of angular orientation between the source and sensor. The instrument's characteristics indicate that it can measure dilation throughout the range of 1-10 cm, but because its clinical reliability is consistent from only 1-7 cm, the equipment needs to be improved in the ways outlined in the text. This measurement, especially when analyzed with the continous measurement of intrauterine pressure, can provide the obstetrician with new insight into the physiology of labor.


Financial strategy considerations in the acquisition of biomedical instrumentation.

Equipment financing by conditional sale, lease-purchase, and true lease transactions is discussed with emphasis on equity and third-party reimbursement. Use of available funds, bank loans, and leasing are compared on a quantitative basis with an incremental cash flow (ICF) analysis. The ICF analysis involves cash accrual and present value techniques. It is demonstrated in a parametric study of lease rates, equipment useful-lives, and reimbursement levels that leasing is the preferred financing route when there is an expectation of obsolescence and when lease term maturities are significantly less than equipment useful-life. Once the decision has been made to lease equipment, it is important to structure the transaction to achieve the optimum mix of rate, term, buy-out options, and available tax shelter. Specific lease situations are given to illustrate the problems that should be considered by the lessee. Lease terms and conditions tailored to the requirements of the users of biomedical instrumentation are discussed in detail. Lessor selection and the importance of a professional working relationship between lessee and lessor also are explored. The capabilities of the lessor (financial, technical, and administrative) can be tapped by the hospital/clinic staff to develop significant advantages in addition to the financing.


An evaluation of advantages and cost measurement methodology for leasing in the health care industry.

Lease financing in hospitals is growing rapidly. Many articles published on the topic of lease financing point only to the benefits that may be derived. Very few articles actually analyze the pros and cons of leasing from a financial cost measurement point of view, which includes real world parameters. This article critically evaluates two articles published in this issue which lead the reader to believe leasing for the most part is a bargain when compared to debt financing. The authors discuss some misconceptions in these articles and point out some facts viewed from a financial analyst's position.


Leasing: is it really the answer to your financing needs?

Leasing hospital equipment may not be the best method of financing such purchases. Early reimbursement agreements offered significant financial benefits to the leasing institution in terms of increased cash flow and additional cash reimbursement dollars. However, changes in the third-party reimbursement formula have partially eliminated the financial advantages of leasing. The author discusses the effect of these changes on leasing agreements, and why hospitals still lease, and answers some of the common assertions in support of leasing.


Culture, community medicine and venereal disease.

This paper reports a remarkable case of venereal disease. It discusses the serious implications and enormous difficulties of control in an Aboriginal community in which striking cultural practices play a unique and major role in disease transmission. Despite known aetiology and the ready availability of inexpensive treatment, patients continue to suffer whilst health education remains extremely difficult.


Amoebiasis: incidence at Royal North Shore Hospital, Sydney.

Seven cases of amoebiasis have been seen at the Royal North Shore Hospital of Sydney, over a nine-year period from 1968 to 1976. Six of these patients had intestinal amoebiasis; these included four with amoebic colitis, one of whom died, one patient with a rectal amoeboma, which was surgically resected, and one case of amoebic dysentery. The patients with amoebic colitis were considered initially to have either ulcerative colitis or Crohn's disease. All patients with inflammatory bowel disease should have rectal swabs or scrapings examined by warm-stage microscopy, rectal biopsy and indirect haemagglutination (IHA) tests to exclude amoebiasis. Three patients had extraintestinal amoebiasis in the form of liver abscesses and one also had pulmonary involvement. In one patient with a hepatic abscess who presented with pyrexia and no evidence of intestinal amoebiasis, the abscess ruptured intraperitoneally. Surgery was performed on three patients, in two cases before diagnosis. Metronidazole appears to be the treatment of choice for intestinal amoebiasis and amoebic liver abscesses. Amoebiasis should be considered in patients resident in Australia who have not recently travelled abroad.


Massive pulmonary embolism during pregnancy treated with streptokinase.

A 24-year-old multipara 34 weeks pregnant presented in shock due to massive pulmonary embolism. Recovery followed thrombolytic therapy, although fetal death occurred early. There were no serious maternal side effects, although hypofibrinogenaemia occurred. Thrombolytic therapy is considered to offer advantages over heparin in this situation.


Health organization in developing countries: innovations in the Peoples Republic of China.

The medical care delivery systems of most low-income countries are largely patterned on those of industrialized societies and are ill suited to the needs of developing countries. The present alternative model of health care in China has evolved after prolonged and often bitter debate extending over twenty years. The system that has been developed is one that appears uniquely suited to the needs of a large rural developing country; but it has been achieved in large part not through the medical profession but by evolving a system based upon participation by the people themselves and the development of new health-worker roles.


School health and four-year-olds.

The results of comprehensive physical, psychological and developmental assessments of 67 four-year-olds are described. The value of this type of review, and the use of nurses and teachers in preschool medical examinations is discussed.


Attempted suicide by insulin overdose in insulin-requiring diabetics.

Four cases of suicidal insulin overdose in insulin-requiring diabetics presented to one hospital in three years. In three cases there was a history of depression; but despite huge doses of insulin (3,000 and 1,500 units) in two, no patient died and only one had residual signs of clinical brain damage. The estimated plasma insulin level was not well correlated with the severity of the hypoglycaemia. It is probable that suicidal insulin overdose is more common than reports in the literature suggest, and may often be unrecognized. The dissociation between huge doses of insulin and the severity of the subsequent hypoglycaemia in diabetics is unexplained.


Coexistence of diabetes and hypothyroidism in South India.

Diabetes mellitus coexisting with primary hypothyroidism is believed to be rare. Seventy-nine such cases were seen between 1960 and 1973. Statistically this association appears to be more frequent than the separate frequencies of the two disease warrant. The patients were mostly females, and invariably obese. Diabetes preceded hypothyroidism in the majority of cases. This frequent association is presumed to be of autoimmune origin.


A case of non-parasitic cystic disease of the liver.

The case is reported of a middle-aged woman with a non-parasitic liver cyst. The patient's left lobe of the liver was excised on her first admission to hospital; a second admission to hospital was caused by an acute small bowel obstruction. An operation was necessary and the patient has had an uneventful recovery.


Low-carbohydrate diet optic neuropathy.

Visual loss occurring in two patients taking prolonged carbohydrate-restrictive diets is reported. The clinical data in these patients point to a specific diet deficiency of thiamine, causing a bilateral optic neuropathy. A discussion of current concepts of thiamine deficiency in neuroophthalmic disorders is presented. It is recommended that patients on low-carbohydrate diets for prolonged periods of time should receive thiamine supplements.


[The antibacterial efficacy of various antibiotics and chemotherapeutical agents (author's transl)].

Sensitivity tests of 5753 organisms (streptococci, Klebsiella, Escherichia coli, enterococci, Pyocyaneus, Pseudomonas aeruginosa, Proteus group and staphylococci) against sulphonamide, nitrofurantoin, ampicillin, gentamicin, cephalosporin, and chloramphenicol are reported, with special consideration of doxycycline, tetracycline and cotrimoxazole. The samples were broken down in accordance with the respective sources. The particularly high resistance quota of co-trimoxazole was striking. The sensitivity quota against doxycycline exceeds that against tetracycline. There were considerable differences in the resistance patterns of organisms from urine samples as compared to samples from other sources.


[Tissue levels following intravenous administration of tetracyclines (author's transl)].

Interested by a comparative trial on tetracycline concentrations in gallbladder, bile and peritoneum 3 hours after administration, we wanted to know the long-term tissue concentrations, measured towards the end of a 24-hour off-drug interval, as these concentrations are particularly important for a bacteriostatic drug. We found that the tissue concentrations of doxycycline in gallbladder wall, lung, muscle, and thyroid gland were 2 to 3 times higher than those of pyrrolidino-methyltetracycline. The concentrations in the skin, in various sections of the intestinal tract and of the peritoneum, and in the gallbladder content were about the same for both drugs. The implications of these data for therapy are discussed.


[Doxycycline levels in serum and pulmonary tissue. Intravenous application of doxycycline in pulmonary surgery (author's transl)].

Doxycycline levels were measured fluorimetrically in the serum and pulmonary tissue of 36 patients undergoing a pulmonary operation. Doxycycline 200 mg was given intravenously 20 hours before operation. The doxycycline concentration in pulmonary tissue (1.03 to 12.30 mug/g) were as high or higher than the serum doxycycline levels (0.94 to 7.82 mug/ml) in the majority of cases. This is possible as the lung has an ample blood supply and doxycycline is a lipophilic drug. There were large variations in the results, which was probably related to the underlying illness and to an altered blood circulation. The side effects were minimal. The daily infusions of doxycycline were continued over 5 days, no conclusions could be drawn about its possible prophylactic effect on postoperative infections.


[Vibravenös--a report of a multicenter trial (author's transl)].

A multicenter trial was conducted in Austria, Germany Holland and Switzerland. A total of 944 patients were included. They had a variety of diagnoses which required hospital admission and intravenous antibiotic therapy. The majority of patients (86.9 p.c.) started therapy with 200 mg doxycycline on the first day. All patients began therapy with an intravenous administration of doxycycline and most were later switched to an oral formulation. Various parameters of response were examined. Resolution of temperature as well as a decrease in associated pain was recorded. Side effects were usually mild and self limiting and were the reason to stop therapy in 1.2 p.c. of the patients. Early improvement was noted in the majority of the diagnostic categories. In 11 p.c. of the cases the response was not indicated or a poor response was noted but overall 89 p.c. of the patients responded to therapy. Doxycycline can be considered a truly useful hospital antibiotic in both its intravenous and oral forms.


[Retrospective studies of resistance patterns of antibiotics in 1971 to 1974 (author's transl)].

A retrospective study was made of the resistance patterns of 16700 pathogenic bacterial strains from the region of Dordrecht (Netherlands) from the years 1971 through 1974. The importance of computer analysis for questions about resistance and antibiotic usage monitoring is supported. The practical importance of those analyses is the fact that antibiotics often have to be given without a known antibiogram. In those instances one must rely on historical data to guide the therapy and to compose a rational antibiotic utilization review. It should be interesting to repeat the study in other areas to establish an overall pattern for a country and to compare the findings on a country-by-country basis.


[Adverse reactions to drugs in hospitalized medical patients (author's transl)].

Prospective research showed that unwanted side-effects resulting from medical therapy were found in 20,6% of all patients hospitalized in our medical clinic during a period of one year. Part of these side-effects was considered a possible reason for admission to the hospital and a cause of complications during the clinical treatment. The side-effects were classified according to their severity, duration, symptomatology and pathogenesis. Furthermore, the frequency of side-effects was studied with regard to age, sex and groups of drugs. It was possible to predict about 80% of the side-effects by considering pharmacological properties and individual risk-factors. The careful integration of these criteria into the treatment plan and the observation of the course of the disease is the basis for calculating the probability of occurrence of side-effects.


[Occurrence of malignant tumors in high-aged patients (author's transl)].

The analysis of macroscopic findings in 2385 autopsies for frequency and distribution for malignant tumors had the following results: Augmented frequency with increasing age was stated for cancer of the stomach, colon, prostate and breast. There is a clear decrease in the frequency of cancer of the lung and of the uterus with increasing age. Severe tumorindependent disease was an almost constant finding in tumor autopsies. The overall frequency of malignant tumors decreases with increasing age.


[The carcinoma of the gastric stump--clinical experiences and observations in 15 years (author's transl)].

From 1960 to 1975 29 patients were treated at our clinic for carcinoma of the gastric stump following resection for benign causes. These cases are casuistically put together and their history, clinic, method of operation, and course after operation are described. 2.38p.c. of all carcinomas of the stomach were carcinomas of the stump. The patients were averagely 38.9 years old at the time of resection for benign causes; they were averagely 60.6 years old at the time of diagnosis of the carcinoma. The so called free interval was therefore 22.2 years. The younger a patient is at the time of primary resection, the longer the free interval will be. The history of complaints lasted 3.4 months; main complaints were pains in the epigastrium, loss of weight, vomiting, and aversion for meat. The carcinomas were located in 60p.c. at the anastomosis, in 36p.c. at the cardia of the stomach. Other locations were distributed over the whole gastric stump. 14 patients could be subjected to gastrectomy with interposition of jejunum, while the rest of the cases were primarily inoperable or were treated with prothesis. All types of carcinomas of the stomach were found in the stump, in 56p.c. the adeno-carcinoma prevailed. 32p.c. of the patients died in the clinic; 17 patients could leave the clinic more or less complaintless. These patients were on the average 24.8 days in the clinic and survived at home averagely 8.5 months. In the introduction, the discussion and on a table the informations of other workers are discussed and their results compared with our findings. We come impressively to the conclusion, that a resection for ulcer is no predisposing factor in the development of a carcinoma of the gastric stump. This causal connection may be established, when wide range statistics are available, which are compiled under controlled and comparable conditions.


[Diagnosis of breast cancer metastatic to the chest (author's transl)].

The records of 100 patients with morphologically proven breast cancer metastatic to the chest retrospectively were analysed. The following manifestations were found by evaluating roentgenographs of the chest and available results of endoscopy and biopsy which were carried out in most of the cases: solid pulmonary coin lesion, multiple pulmonary coin lesions, lymphangiosis carcinomatosa, bronchostenosis caused by cancer, mediastinal lymph node metastases. Since life expectancy in approximatively 70 per cent can be increased by chemotherapy the authors put emphasis on the importance of early diagnosis of metastatic breast cancer disseminated to the chest.


[Primary tumors of the ureter (author's transl)].

13 own cases of primary tumors of the ureter are presented and discussed with reference to the presenting clinical symptoms, diagnostic procedures, and therapy. In our patients, excretory urography was not always of diagnostic value, whereas retrograde pyelography contributed to the correct diagnosis. The radiographic appearance of ureteral tumors has to be differentiated from strictures. In one case with a calcified papilloma, preoperative roentgendiagnosis suggested an ureteral stone.


[Investigations of the clinical course of acute myocardial infarction. I. The fibrinolytic treatment of acute myocardial infarction with streptokinase (author's transl)].

In 26 hospitals a study was carried out to investigate the influence of fibrinolytic therapy on mortality in hospital in acute myocardial infarction. The study was concerned with the question whether fibrinolytic therapy in acute myocardial infarction could lower the hospital mortality and whether fibrinolytic therapy should be recommended as an additional therapy for any type of hospital, irrespective individual differences in treatment. 483 out of 1463 patients were treated with streptokinase. These patients were randomized in two groups. Group I was treated in the usual way additionally streptokinase was given, group II without streptokinase. Both groups were similar regarding the course of illness and clinical data. It could be shown that the mortality was not significantly lowered by streptokinase. But in case of shock the mortality seemed to be lower after streptokinase, this difference not being significant.


[Investigations of the clinical course of acute myocardial infarction. II. Epidemiological facts (author's transl)].

1463 patients with acute myocardial infarction were treated in 26 hospitals in Northern Germany from June 1972 till August 1973. The time elapsed between onset of symptoms and admission to the regional hospital was similar in rural patients and those living in cities. 39% were admitted later than 12 hours after onset of symptoms. Having survived the prehospital phase the age of infarction did not influence the mortality. The treatment in the different hospitals was in no way standardized, except the treatment with streptokinase. Regarding this procedure, the following results can be presented. The overall mortality was 25.8%. Mortality was higher in cases of high age, preexisting myocardial failure, diabetes mellitus and in cases of shock and/or arrhythmia. Anterior wall infarction showed a higher mortality than posterior wall infarction. In this study the average results of treating 1463 patients with acute myocardial infarction treated in Northern Germany were presented.


[A controlled clinical study of early mobilisation of patients with myocardial infarction (author's transl)].

This is the report about 265 patients with recent transmural myocardial infarction. In the first week of hospital treatment 63 died. From the remaining 201 patients 101 fulfilled the conditions for early mobilisation of the WHO. In a controlled study these patients were divided in 2 groups: group 1 started the programme of early mobilisation the 7th day and group 2 was the control group which was mobilized after 3 weeks of bed rest. The 2 groups were comparable in the clinical course and had 2% of letality. The remaining 100 patients with conditions against early mobilisation were conservatively treated with 3 weeks of bed rest. The letality in this group was very high with 23%.


[Behaviour of erythrocytes in patients with aortic of mitral stenosis (author's transl)].

The behaviour of red blood cells was studied in 17 patients with aortic stenosis and 14 patients with mitral stenosis. Anemia was present only in 1 out of 17 patients with highgraded aortic stenosis. 8 of the 17 patients showed a reduced survival time of the red blood cells indicating hemolysis in a compensated stage. 14 cases of mitral stenosis showed no evidence of hemolysis. There was a significant inverse relationship (r = --0,85) between the valve gradient and the survival time of the erythrocytes in patients with aortic stenosis; valve area and survival time were directly related (r = 0,75). In mitral stenosis, there was no significant correlation between gradient or valve area and survival time. This suggests that the gradient through the valve rather than the reduced valve area is responsible for the damage of the erythrocytes; in addition, hemolysis appears to be dependent on pressure gradient rather than on valve pathology or reduction of valve area per se.


[Liver damage after resection of the stomach: evaluation of 215 cases (author's transl)].

Only 11% out of 215 patients with resection of the stomach had a normal liver if the term of the resection was not longer ago than 30 years. Contrarily the deposition of fat became less frequent with increasing distance from the operation term while deposition of iron (siderin) was demonstrable nearly equaly in all groups. Age and sex did not influence the behaviour of the liver after resection of the stomach. The information value by blood transaminase activity (GOT/GPT) decreases with the distance of time from the resection term. Alcoholics (n = 20) had less shares of post resection liver harms than non-alcoholics. Thus alcohol seems to be not a bigger risk for resectioned as for people with normal stomach. Repeated liver biopsies after different intervals of time pointed out that a change for the worse happened more often with increasing distance to the resection term. Therefore resected patients should be examined regularly, including liver biopsy, as to discover in time a growing up liver damage. After resection of the stomach discovered liver diseases refer to a damage caused by that stomach disease which induced the operation.


[Quantitative serum immunoglobulin determination: differential diagnostic significance for liver disease (author's transl)s].

The serum immunoglobulin (Ig) G, A, and M levels were investigated with respect to their differential diagnostic significance, pathogenesis and estimation of prognosis of different forms of liver disease. The sera of 204 patients with acute hepatitis, fatty liver I and II, and cirrhosis, and of 110 healthy adutls were quantitatively determined for immunoglobulins. 1. IgG- and IgA-concentrations higher than 2000 mg% and 330 mg%, respectively, indicate chronic aggressive hepatitis or cirrhosis, and exclude all other groups. 2. A clear correlation between HBsAG (Australia Antigen) and immunoglobulin content could not be demonstrated in any group; 3. A significantly elevated level of IgA was observed in alcoholic cirrhosis when compared to non-alcoholic cirrhosis. No such differences were found inhe other groups. 4. Acute and chronic persistent hepatitis show a similar increase of immunoglobulins. Thus persistent high levels of Ig following acute hepatitis indicate the development into a chronic hepatitis. 5. A relative increase of IgA rather than IgG corresponds to the degree of inflammatory activity of a liver process.


[Silymarin for the treatment of acute viral hepatitis? Report of a controlled trial (author's transl)].

Silymarin has been claimed to have a benificial effect in various types of liver injury. In a prospective study in patients with acute viral hepatitis (n = 151) the effectiveness of this drug on the cause of the disease was tested. The groups with and without Silymarin (Legalon) were comparable concerning age and sex distribution and the frequency of HBs-antigen positive hepatitis; Laboratory findings (total serum bilirubin, activity of GOT, GPT and alkaline phosphatase and prothrombin time) were determined in intervals of 5 to 7 days over a period of 5 weeks beginning with the onset of jaundice. There were no statistical significant differences between both groups in the decrease of mean values of all parameters tested. The frequency of nearly normalized values of transaminases and serum bilirubin after 10, 20 and 30 days was not higher in the group treated with Silymarin as compared to the controls. It is concluded that Silymarin has no favourable effects on the cause of acute viral hepatitis.


[Basic pressure in the pancreatic duct and in the bile duct: results from 50 standardized duodenoscopic transpapillary pressure measurements (author's transl)].

In 90 patients pressure measurements in the pancreatic duct (50 cases) and in the common bile duct (20 cases) were performed endoscopically. In the normal pancreas an averaged basis pressure in Wirsung's duct of 22.2 cm H2O was found with a range of 9.6 to 37.0 cm H2O. In two cases of marked chronic pancreatitis and in one case of pancreatic carcinoma the secretion pressure was considerably diminished. The mean basic pressure of the common bile duct amounted to 12.0 cm H2O with a range of 7.3 to 17.0 cm H2O. The pressure values in the duodenum were found to be considerably lower than in the pancreatic duct and the bile duct; they amounted to 5.3 cm H20 with a range of 0.6 to 10.9 cm H20. In both ducts two different patterns of ondulations were found: tracings of slight ondulations, i.e. slow pressure changes with a constant average pressure and tracings of coarse ondulations with quick increase and drop in pressure. It will be discussed, how these findings can be related to physiology and pathophysiology of the pancreatic and biliary duct system. The clinical relevance for detection of excretory insufficiency of the pancreas and of pathologic changes leading to stenosis of the duct system are considered.


[The importance of the serumlipaseevocationtest and the retrograde pancreaticography for the diagnosis of chronic pancreatic affections (author's transl)].

Comparative studies between activity of serumlipase, lipaseevocationstest and endoscopic retrograde cholangiopancreaticography (ERCP) in 45 patients with chronic pancreatitis, pancreatic cysts or pancreatic carcinoma confirm, that elevated enzyme values after caerulein stimulation indicate an alteration of the pancreatic parenchyma. However, this findings does not give information on the etiology of the damage. On the basis of the presented results it seems that the lipase-evocationstest has only limited value as screening method within the total of clinical methods for the assessment of light and medium severe stages of chronic pancreatitis and accompanying forms of pancreatitis. There is no evidence that this method may be used for screening for carcinoma of the pancreas. A positive result gives a valuable information, but the lack of an increase of lipase activity does not exclude the existence of pancreatic affection. In each case with clinical suspicion for pancreatic disease further diagnostic investigation by the ERCP and additional radiographic methods should be performed.


[Pancreatic pseudocysts--clinical picture and surgical treatment].

Report about 98 cases of pancreatic pseudocysts and also elaboration on the etiology, pathogenesis and details of this disease. The operative method of choice is to establish the internal anastomosis. As long as the anatomic conditions and especially the structure of the cyst permit it, such anastomosis should be performed. We applied this method in 57.2 p.c. of the cases altogether. Y-anastomosis (Roux) proved to be the best. We applied it in 35.9 p.c. of our patients. For patients in bad general condition, outside drainage operation in the sense of marsupialisation is often the only possible and at the same time life-saving intervention. We performed this operation in 42.8 p.c. of our cases. Because of the clear increase in number of pancreas diseases in the last years, there is also a higher frequency of pancreatic pseudocysts. Their diagnosis and therapy are therefore important.


[Focal mucosal hyperplasia of the appendix (author's transl)].

On a 20-year-old male patient and on a 67-year-old female patient, we incidentally detected as histologicbioptic findings after routine appendectomy a focal mucosal hyperplasia of the appendix. Basing on these cases we give a survey on the literature pertaining to these rate cases of mucosal alterations of the appendix published up to now, and discuss the problems of these mucosal hyperplasias.


[Fatigue fractures of the femoral neck (author's transl)].

By means of one case problems of diagnosis and therapy of fatigue fractures of the fermoral neck are demonstrated and discussed by comparison to recent reports in literature. In case of uncertain diagnosis we recommend surgical revision of the fractured zone with take off of bone tissue for histological examination, especially in order to exclude a malignant bone process.


[Thermometric investigations about the efficacy of beta-escin to reduce postoperative edema (author's transl)].

Beta-escin is highly effective in reducing postoperative edemas and swellings. It was tried to demonstrate the effect of beta-escin using the thermometry. The temperature of soft tissues and bones can be measured with the help of the thermometry, in this way the circulation of the skin can be determined. In 65 test persons so-called normal thermograms were established, using the infraredthermometer KT 41, which makes registrations without touching the skin. In 53 patients the temperature of the skin was checked after surgery of the hand. 27 patients received beta-escin (Reparil); 26 patients without medication served as controls. In every case the temperature of the operated hand was compared to the other hand. Among the patients, who received escin, the temperature of the operated hand rose for two days following surgery; afterwards it fell quickly. Among the controls the skin-temperature rose up to the 4. day after surgery and decreased slowly. These results demonstrate clearly that after using beta-escin there is a quick reduction of postoperative inflammation and edema.


[Bilateral hamartomas of the kidneys (author's transl)].

A case of a patient with multiple bilateral hamartomas of the kidneys is reported. The diagnosis of polycystic renal disease, suggested by the urographic studies had to be corrected after renal angiography. A well established diagnosis, basing on the striking angiographical findings was only possible, when we took notice of an adenoma sebaceum and other signs of the tuberous sclerosis complex. In cases of circumscribed unifocal lesions the antiographic findings may cause difficulties in the differential diagnosis between hamartoma and malignant hypernephroma. Therefore it is important to pay attention to other stigmata of tuberous sclerosis (Bourneville-Pringle's-syndrome). The differentiation between benign hamartoma and malignant hypernephroma may be possible by angiographic criteria alone, but many of the reported typical signs are of limited value.


[Investigations on the pharmacokinetics of pentoxifylline in chronic renal failure (authors transl)].

The pharmacokinetical behaviour of 14C-labelled pentoxifylline was investigated in normal volunteers and in patients with different stages of impaired renal function. It was shown that in patients, having a creatinine-clearance of less than 10,0 ml/min., occurs an accumulation of pentoxifylline. This finding leads to the conclusion that in patients with advanced renal failure the daily dose of pentoxifylline should be adjusted to the diminished renal elimination.


[Theoretical basis and practical carrying out of an APTT control test for exact heparin monitoring (author's transl)].

We presented in this journal (Med. Klin. 71 [1976], 116), a procedure how to avoid hemorrhage risks due to heparine giving during hemo-dialyses. In this presentation is found the theoretical basis of the "minimal heparinisation". The practical carrying-out of the APTT (Activated Partial Thromboplastin Time)-control test as demonstrated by the 1200 bedside test cases, was done in order to give the personal without lab experience a practical guideline in the hand.


[Psychological problems in obesity (author's transl)].

The MMPI was administered to 209 obese women and 72 obese men before onset of a weight reduction regime. Obese subjects differ in a variety of MMPI-standard-scales from the standard population as well as from a control group of healthy women: 1. Scales Hypochondriasis (Hs) and Hysteria (Hy) have significant higher values for the obese. This somatic impairment grows in the group of obese women with increasing age and obesity. In men, scale Hs corresponds to the degree of overweight but the youngest male age group (up to 19 years) has a Hs-peak as well as men above 35 years of age. 2. Higher than normal values for obese men and women in scales Depression (D) and Psychasthenia (Pt) in the obese point towards emotional upset. 3. Obesity does not decrease Hypomania (Ma) values for men or women; to the contrary: obese men felt more active than the standard population. With growing age women had a decrease in Ma-values.


[Changes of kidney function in obese subjects during absolute fasting (author's transl)].

In 28 obese subjects the influence of a 15-days fasting period on the kidney function was investigated by continuous measurement of the clearances for creatinine, urea and uric acid. In the course of fasting time the serum concentrations of creatinine in comparison to the initial value significantly increased, the creatinine clearance maximally decreased about 40%. The serum concentrations of urea were found lower, whilst the clearance of urea increased. Moreover a distinct increase of the serum levels in connection with a significant decrease of the uric acid clearance was to be observed. Under conditions of strict fasting changes of the kidney function are evident, whose intra- and extrarenal reasons are discussed.


[Plasma lipid concentrations during the healing phase after myocardial infarction (author's transl)].

In the initial phase after myocardial infarction the cholesterol and triglyceride concentrations were statistically significantly decreased with respect to the first evaluations. Subsequent analyses during the following four to five weeks revealed some increase in the plasma lipid level. On discharge from hospital the mean plasma lipid concentrations were elevated compared to the first day after myocardial infarction. The time courses of the changes in concentrations of the particular lipids were different. On discharge three quarters of the patients with myocardial infarction had developed hypertriglyceridaemia (hyperlipoproteinaemia type IV or type IIb). Our investigations demonstrate the difficulties in discovering a possible disorder in lipid metabolism during the healing phase after a myocardial infarction.


[Mode of action and control of "low dose heparin" (author's transl)].

Investigating the mechanism of action of "low dose heparin" it could be shown that this type of anticoagulation--in addition to other mechanisms--inhibits the contact phase of the intrinsic coagulation system. Thus "low dose heparin" would be directed against the hypercoagulability that arises via increased contact activation of the intrinsic system by inflammatory or degenerative processes of the vessel walls. Further the biological significance of "low dose heparin" was demonstrated by a prolongation of the half life of 125J-fibrinogen. In general a laboratory control of "low dose heparin"-prophylaxis is not required. In patients with an increased "tolerance" for heparin, however, the determination of the thrombin time with a thrombin-solution of low concentration (1 N.I.H.-unit/ml) might be useful to indicate whether the dosage of heparin has to be increased or not.


[Log-normal distributed plasma cortisol levels of four daily measurements in normal subjects. A comparison of the fluorescence method after de Moor with a radioimmuno assay of plasma cortisol (author's transl)].

The present paper describes the plasma cortisol concentrations on four daily measurements in normal subjects assayed with the fluorescence method after de Moor and with a radioimmuno assay. A comparison of these two methods shows that the determinations of plasma cortisol with the fluorescence method always yielded higher values. Both methods are sensitive enough to detect the circadian rhythm of cortisol secretion. For the purpose of routine diagnostics it is sufficient to measure the maximal and minimal concentrations of plasma cortisol in blood samples taken at 8 a.m. and 8 p.m., respectively. The plasma cortisol measurements should only be attempted after allowing a few days of adaption to the hospital situation. Table 2 shows that the normal plasma cortisol levels are represented only by log-normal distributed values. These concentrations are lower than the linear distributed levels reported so far.


[Symptoms and clinical findings in bronchial cancer according to the TNM-classification (author's transl)].

500 patients with proven bronchial cancer have been classified according to the TNM-system in a retrospective study. By classifying symptoms, clinical and technical findings into the classes of the TNM-system the frequency of individual symptoms and findings at different stages of bronchial cancer was examined statistically. The majority of the investigated parameters demonstrated an increasing frequency with advancing T-classes.


Breast cancer: lack of prognostic value of adrenal pathology at adrenalectomy.

The adrenal glands of 58 patients undergoing adrenalectomy for advanced breast cancer were reviewed and correlated with subsequent course of the patients' disease. Three patients had thecomatous metaplasia in the adrenal cortex, six patients had myelolipomatous changes, and 13 patients had metastatic breast cancer in their adrenal glands at the time of adrenalectomy. Neither the presence of metastases nor myelolipomatous changes were associated with a long disease-free interval, a long period from mastectomy to adrenalectomy, or a prolonged postadrenalectomy survival. The patients with metastatic breast cancer in the adrenal glands had more widespread disease than patients without adrenal metastases. The presence of breast cancer metastases in the adrenal glands at the time adrenalectomy identifies patients further advanced in the course of their disease, but is not related prognostically to the effect of adrenalectomy.


Neurotoxicity due to CNS therapy for leukemia.

CNS symptoms ranging from mild to lethal have occurred following CNS radiotherapy and intrathecal chemotherapy. Cranial radiotherapy often produces signs of mild encephalopathy, with predominance of somnolence. In rare cases, it appears that CNS radiotherapy may be followed by progressive encephalopathy. Intrathecal methotrexate frequently causes symptoms of meningeal irritation. Occasionally cases of weakness and paralysis, and rare instances of severe encephalopathy, may occur. However, in leukemic children treated with intensive chemotherapy and CNS radiotherapy who develop neurological complications, it is often difficult to determine which of many possible factors may be causing the CNS symptoms. The pathogenesis of the various forms of methotrexate neurotoxicity is poorly understood. The best-established cause for these symptoms is high concentrations of methotrexate in the CSF or porlonged exposure of the brain to low CSF concentrations of methotrexate. These elevated concentrations of the drug may in turn be due to impaired elimination of the drug from the cerebrospinal fluid (usually due to overt CNS leukemia) or to increased dosage in relation to cerebrospinal fluid volume (due to adolescent age). Leukoencephalopathy is occasionally found at autopsy in children given intensive therapy with CNS radiotherapy and intrathecal methotrexate, together with intensive systemic chemotherapy. It was proposed that alteration of the blood-brain barrier by cranial radiotherapy allows systemically administered anti-leukemic drugs to enter the brain and to cause necrotic changes in the CNS white matter. Leukoencephalopathy also occurs following intraventricular administration of methotrexate. CNS-toxicity due to intrathecal cytosine arabinoside is clinically similar to the symptoms seen following intrathecal methotrexate.


Cicatricial ectropion secondary to 5-fluorouracil therapy.

Four cases of cicatricial ectropion secondary to prolonged systemic administration of 5-fluorouracil are described. In 1 patient ectropion resolved with conservative treatment and discontinuation of 5-FU. Another patient developed the ectropion terminally and died before its resolution. In 2 patients surgical repair of the ectropion was unsuccessful in relieving conjunctival symptoms while 5-FU was continued. With prolonged adjuvant chemotherapy programs utilizing 5-FU, this complication may be seen with increasing frequency. Conservative management should be attempted, and patients with this problem should be reassured that symptoms will resolve when 5-FU is stopped.


Treatment of rhabdomyosarcoma in children with surgery, radiotherapy and chemotherapy.

From May, 1970 through December, 1972, Children's Cancer Study Group entered 112 patients on an amended treatment program for rhabdomyosarcoma and undifferentiated sarcoma in children. These patients had Group II disease with residual tumor remaining after surgery, or metastatic disease at onset. Another group consisted of patients who previously had treatment with surgery and radiotherapy and had recurrent disease. Cyclophosphamide was added to a previously used drug regimen which consisted of actinomycin D and vincristine. The drugs were given sequentially in repeated cycles for 18 months. Of 97 evaluable patients, there were 24 with microscopic residual disease, 37 with gross residual disease, 22 with metastatic disease at onset, and 14 patients who were treated with chemotherapy for the first time with recurrent or metastatic disease. All patients have been followed for 3 or more years. Survival in each group was 70.8%, 43.2%, 27.2%, and 28.2%, respectively. Although the number of complete remissions was greater than with two-drug therapy, survival with three-drug therapy was not significantly different than that seen in the earlier study.


Case reports and studies of paraneoplastic hypotension: abnormal low pressure baroreceptor responses.

Intrathoracic stretch receptors regulate adjustments of the vasculature to gravitational changes and influence urinary water and solute excretion. Few reports of pathologic states involving interruption of these regulatory mechanisms have appeared. Two patients with orthostatic hypotenstion related to advanced intrathoracic carcinoma were studied, utilizing tilt-table examinations and immersion of the entire body in water to test the function of their intrathoracic baroreceptor reflex arcs. Both patients showed abnormalities of antidiuretic hormone level and sodium excretion as compared with normal controls. This suggests that total immersion is a safe and convenient test of the low-pressure baroreceptor system in patients with suspected dysfunction. Three patients are also reported whose charts were reviewed posthumously. Although they were not tested in the laboratory, their clinical data suggest that they too had been suffering from an interference with the transmission of impulses from the intrathoracic receptors.


Choline antagonism of methotrexate liver toxicity in the rat.

Because of the frequent reports of hepatic toxicity associated with long-term administration of methotrexate, a rat model was developed utilizing daily methotrexate administration. This model revealed an incidence of fatty metamorphosis of over 80 percent, atrophy and necrosis of 30 percent, and fibrosis of 10 percent. Fatty liver changes did not differ substantially from control animals in those animals receiving long-term thydroxyurea, an agent which, like methotrexate, inhibits DNA synthesis but unlike methotrexate, does not impair methylation reactions. Because choline has a lipotropic effect and because its synthesis requires methylation, an attempt was made to block the liver toxicity of methotrexate by simultaneous administration of choline. Animals so treated did not show the pathologic changes in the liver characteristic of methotrexate treatment alone. Furthermore, the accumulation of triglycerides in the liver which was characteristic of methotrexate administration was markedly reduced in those animals receiving choline. These data strongly suggest that, in the rat model, methotrexate produced liver toxicity by virtue of an effect other than inhibition of DNA synthesis; and that this toxicity can be blocked without impairing methotrexate effect on bone marrow by the administration of choline, a lipotropic agent requiring methylation for its synthesis. It is suggested that these results may have implications for human therapeutic situations involving long-term administration of methotrexate.


Post-hypophysectomy insulin response in patients with advanced breast cancer.

Seven postmenopausal women with metastic breast cancer underwent transsphenoidal hypophysectomy. The rate of disappearance, k*, of iv glucose and insulin following iv glucose and l-arginine infusion was determined before and after the ablation. The k* was estimated with a linear least squares weighted regression method. The insulin secretory capacity of the pancreas before and after the ablation was evaluated with the index of insulinogenic reserve, the index representing the quantity of insulin secreted per unit of glycemic stimulus. Following iv glucose and arginine, there was no significant difference in the mean k* for glucose and insulin, before and after the ablation. The insulinogenic index before was lower than the normal. After hypophysectomy, the index decreased further for the first 30 min following iv glucose. In patients with advanced cancer the index of insulinogenic reserve is lower than normal and is suppressed further by hypophysectomy.


Interpretation of star test pattern images.

The star test pattern image contains a large amount of information about the focus OTF which is not presently used. A mathematical analysis of these images for the special case of separable and symmetrical focal spots is presented. Circular blur loci are identified and their changes over the imaging field are described. Harmonic distortion and its application are described. Sources of measurement error are discussed.


Field characteristics of geometric unsharpness due to the x-ray tube focal spot.

The basic theory of field characteristics is discussed. It is shown that the point spread function and optical transfer function (OTF) of geometric unsharpness at any arbitrary field position can be derived from those at the central beam position. At all locations in the radiation field, the OTF in a direction parallel to the x-ray tube cathode-target axis does not depend on the field position X, which is perpendicular to the tube axis, whereas the OTF in a perpendicular direction does not depend on the field position Y, which is parallel to the tube axis. The theoretical result is used to demonstrate the field characteristic of the uniform, square focal spot.


Effect of asymmetric focal spots in angiography.

The effect of asymmetric focal spots in blood vessel imaging is investigated by computer simulation. Phase distortion effects are studied in isolation from MTF effects. Calculations are done for a number of symmetric and asymmetric foci with identical standard deviations. It is concluded that blood vessel image degradation due to focus asymmetry per se is small and that the LSF standard deviation is a useful size parameter for both symmetric and asymmetric foci.


Spectral considerations for absorption-edge fluoroscopy.

In our previous reports on absorption-edge fluoroscopy, it was not possible to relate fully the subtleties involved in the selection of spectral parameters. This paper is intended as an overview of this important aspect of the technique. It is shown that, by using the 1-kVp, 2-filter technique, it is possible to image certain elements (e.g., iodine and xenon) in the presence of tissue variations of +/-2 cm about the thickness at which perfect tissue cancellation takes place. Use of logarithmic signal processing extends this range, but bone thickness variations may not be accomodated because only two x-ray energies are involved in the imaging process. Use of a 3-kVp, 3-filter technique with logarithmic signal processing is shown to solve this problem. Computer simulations show that 1-mg/cm2 iodine may be imaged in the presence of 10 cm or more tissue variations and 2000-mg/cm2 bone variations.


Photoactivation ratios for specification of high-energy x-ray quality: part I, 15-40-MV x rays.

A sensitive and relatively simple method for obtaining an index of the spectral quality of high-energy x rays is presented. The method is based upon the use of photoactivation threshold detectors. Photonuclear reactions produce measurable amounts of radioactivity for radiation exposures of several thousand roentgens. Since the threshold energies for photonuclear reactions vary for different nuclei, the ratio of radioactivity induced in two appropriately selected foils is very sensitive to the x-ray spectrum. Photoactivation ratios (PAR) have been measured for 20-35-MV x rays using Co, Cu, Y, Zr, and Au activation foils. It is shown that the PAR method offers a sensitive and practical means for quality control of x-ray spectra, comparison of high-energy accelerators, and the measurement of variations of spectral quality control at different point in an irradiated volume.


Correction for spectral artifacts in cross-sectional reconstruction from x rays.

A monoenergetic response correction is described which, along with adequate filtration, may be used to remove the spectral shift artifact encountered in three-dimensional reconstruction from x rays. Reconstructions were carried out by means of a convolution algorithm for simulated data using this method. These are compared with reconstructions obtained using fixed-length water-bath scans as a remedy for the special artifact. These studies suggest that the spectral artifact can be successfully eliminated from computerized cross-sectional scans without resorting to the use of the water bath while, at the same time, improving quantum statistics and/or permitting operation at a lower tube current.


Use of 48Ca as a stable isotope tracer analyzed by proton activation.

The use of the stable isotope 48Ca as a tracer in biological systems has been studied. Determination of 48Ca concentrations in samples was accomplished by proton activation via the (p,n) reaction with subsequent measurement of gamma-ray spectra from 44-h 48Sc and 4-h 44Sc. With protons of about 5.5 MeV and a Ge(Li) gamma-ray detector, and with no chemical processing of the samples, ratios of these two radioisotopes can be determined with sufficient precision to allow 48Ca tracer studies to be performed with sensitivity at least equivalent to that possible with the common 45Ca radioactive tracer.


Relationship between tissue-phantom ratio and percentage depth dose.

The relationship between the tissue-phantom ratio and central-axis percentage depth-dose data is derived. Relationships between the tissue-phantom ratio, tissue-maximum ratio, and tissue-air ratio are given. A simple model is developed which suggests that the degree to which the TPR and TMR are independent of distance from the source depends largely on the collimator/flattening-filter scatter.


Calibration in water versus calibration in air for cobalt-60 gamma rays.

In the United States it is common practice to calibrate Cobalt-60 teletherapy machines "in air," despite recommendations by the International Commission on Radiation Units and Measurements (ICRU) and other organizations that calibration be accomplished by measurement at 5-cm depth in a water phantom. A comparison has been made between the results of ionization measurements in air at 80.5-cm distance from the source and in water at 80-cm source-skin distance (SSD) for the determination of absorbed dose at three depth (5, 10, and 15 cm) for each of three fields sizes (6 X 6, 10 X 10, and 20 X 20 cm2), for a total of 42 Cobalt-60 machines. The mean of the ratio, absorbed dose from in-water measurements to absorbed dose at the same depth calculated from in-air measurements, ranged frt 5-cm depth for a 20 X 20-cm2 field size. Reasons for the differences are offered, and compliance with ICRU recommendations is suggested.


Photoactivation ratios for specification of high-energy x-ray quality: part II, 4-15-MV x rays.

A sensitive and relatively simple method for obtaining an index of the spectral quality of x rays in the 4-15-MV range is presented. The method is based upon the simultaneous production of 115mIn by inelastic scattering of x rays by an indium foil and the production of 116mIn by neutron capture, where the neutrons are obtained from the photodisintegration of deuterium. Since the cross sections for the production of 115mIn and 116mIn have markedly different energy response functions, the ratio of radioactivities is very sensitive to the incident x-ray spectrum. Using a detector consisting of an indium foil sandwiched between two plastic bottles of D2O, photoactivation ratios (PAR) have been measured for 4-, 6-, and 10-MV x rays. It is shown that the PAR method offers a sensitive and practical means for quality control of x-ray spectra and comparison of high-energy accelerators.


Postmortem transition in the dynamic mechanical properties of bone.

Measurements of dynamic shear compliance versus dead time at room temperatures are reported for a sample of rabbit bone and several samples of human bone, including an extracted wisdom tooth. In all cases an abrupt, second-order transition is observed in one or both components of the audio-frequency complex shear compliance, J*b = Jb; - iJb", at about 5 hours after death; this is considered to be an indication of the life-to-death transition in bones.


Verification timer for radiation therapy machines.

Many cobalt and x-ray therapy machines use mechanical timers to control the given dose. There is no other timer on the machine to veryfy that the correct time was set or that the timer did not malfunciton. This article describes a digital timer that has been installed on the MIR therapy machines as a lapsed-time indicator.


Composition of A-150 tissue-equivalent plastic.

In recent years, the use of tissue-equivalent materials has become quite common in fast-neutron dosimetry, with the A-150 plastic developed by Shonka et al. probably the most popular. Information on this specific plastic is scantily reported in the literature and as a consequence a preponderance of authors unknowingly reference an article by Shonka describing an early version of a tissue substitute plastic but having a different elemental composition than the present A-150 formulation. We have reviewed the results of 21 chemical analyses which have occurred over a time span of four years on a total of 14 samples of A-150 plastic and based on these data and the formulation of the plastic, have arrived at a suggested composition for A-150 tissue-equivalent plastic. The ambiguities of water absorption by nylon, one of the components of the plastic, and the uncertainty this reflects in the composition of the plastic were evaluated.


Dosimetry measurements and analyses of 10-MV x rays for Clinac-18.

Radiation parameters for two Varian Clinac-18 10-MV x-ray units were measured and compared with the same parameters for the Toshiba LMR-13 and the Arco Mevatron XII. Comparison of the percentage depth dose, surface dose, and depth of maximum ionization as a function of field size are presented.


Computer simulation study of Siemens star x-ray image artifacts.

In the Siemens star image, exact determination of the first disappearance frequency, which is used to measure the focal spot size, is difficult since the disappearance band has a finite width and the image also has other artifacts. The origin of these artifacts and their appearance was studied by Siemens star image simulation on a digital computer. The simulated images were manipulated by using many different modulation and phase transfer functions. It is shown that the bending of spokes is not related to zero contrast; exact triplet splitting can occur only at the disappearance frequency, and therefore splitting is a valuable indicator of that frequency.


Dependence of cytoplasmic on mitochondrial protein synthesis in K. Lactis CBS 2360. I. Biochemical analysis.

In the "petite negative" yeast Kluyveromyces lactis (strain CBS 2360) growth is inhibited by the same Erythromycin concentrations on fermentable and non-fermentable carbon sources. The minimal inhibitory concentrations of Erythromycin does not affect respiration, but completely inhibits total aminoacid incorporation by the cells in conditions in which permeability effects can be ruled out. The effect of the antibiotic on the "in vitro" protein synthesis by cytoplasmic and mitochondrial systems shows that inhibition is effective only at the mitochondrial level. Results suggest that the inhibition of growth and of total protein synthesis is a consequence of the inhibition of mitochondrial protein synthesis.


Dependence of cytoplasmic on mitochondrial protein synthesis in K. lactis CBS 2360. II. Genetic studies.

A few eryR mutants independently isolated from K. lactis CBS 2360 display a conditional lethal phenotype at the temperature of 36 degrees C. In addition to drug resistance, also conditional lethality shows a non-Mendelian pattern of inheritance and is affected by exposure of the cells to Ethidium Bromide, indicating that in this yeast mitochondrial DNA controls cell viability. The results obtained from biochemical analysis suggest that the cellular functions in which are involved the gene products of the mitochondrial mutants analized are cytoplasmic protein and RNA syntheses.


EcoRI-sensitive mutation of T7 phage.

It is known that DNA from phage T7 is not cleaved by restriction endonuclease EcoRI. However, DNA from phage T7am28 (gene 5) mutant (Studier, 1969) was found to be cleaved by the endonuclease at one site. The site is located at 0.46 fractional length from the left end of the molecule. The mutation which makes T7 DNA sensitive to the endonuclease is separable from the amber nutation and located between am28 and am233 (gene 6).