This 46-year-old woman was initially admitted to our hospital with headache, progressive decrease in visual acuity, and a fever above 38.5 C for the last month, in addition to polyuria and polydipsia for the last 2 weeks. Upon admission, her neurological exploration was unremarkable. Visual exploration disclosed a reduced visual acuity of both eyes, 20/200 in the right eye and 20/40 in the left one. The initial perimetry evidenced a homonymous left inferior quadrantanopia, whereas the funduscopic exam did not reveal any abnormality. All her baseline endocrine tests were also normal at this time. The brain MRI displayed a 1.5-cm mixed solid-cystic lesion occupying the lower 3V and adjacent hypothalamic-chiasmatic region [Figure 1a-c]. As the patient was seropositive for HIV infection and had suffered from lung tuberculosis several years before, this lesion was presumed to correspond to a cerebral tuberculoma related to the HIV infection, and specific therapy with isoniazid and rifampicin was initiated.
Six months later, the patient was admitted again due to visual deterioration and symptoms of panhypopituitarism and diabetes insipidus. She was treated with hormone replacement therapy and also received psychiatric assessment for a depressive disorder which had worsened in the last year.
At this point, a thorough neuro-ophthalmological and neuroradiological evaluation was performed. The patient could only see light with her right eye and could distinguish hand movements from 2 m distance with the left one. Visual fields were impaired severely in both eyes with a generalized loss of sensitivity in the right one and sparing of the upper nasal quadrant of the left eye (Figure 2a, perimetry on 07/16/2012). A mild blurred temporal border in the left macula was observed on funduscopic exam. OCT (SD-OCT SPECTRALIS, Heidelberg Engineering, Heidelberg, Germany, Software 5.3) was used to reveal slight thinning of the RNFL in the superior and temporal wedges of the right eye (90 mum on average) and atrophy of the temporal wedge in the left eye (Figure 3, preoperative OCT). An MRI study showed a significant enlargement of the 3V lesion, which had a basal cauliflower-like nodule and a cystic upper component [Figure 1d-f]. The chiasmatic (suprasellar) cistern was tumor free, and both the pituitary stalk and the pituitary gland were anatomically intact. The optic chiasm was grossly distorted, showing a potbelly downward deformation on coronal sections, due to tumor infiltration [Figure 1e]. In addition, on T2-weighted axial images, the optic tracts displayed a "moustache-like" appearance, characterized by a hyperintense signal of edema extending along both optic tracts and into the adjacent hypothalamus [Figure 1d].
The tumor was approached through a right frontotemporal craniotomy. After opening the Sylvian fissure, the optic chiasm was exposed. It was displaced against the tuberculum sellae and presented a quite swollen and shortened appearance [Figure 4a]. The tumor occupying the 3V was approached through the lamina terminalis, which was found to have a ballooned and thinned aspect protruding above the optic chiasm. The lesion could be dissected out from the 3V walls, except at its solid basal portion where a solid tongue of the tumor infiltrated the right posterolateral region of the chiasm and extended into the swollen proximal portion of the right optic nerve [Figure 4a]. After severing the intrachiasm tumor attachment with careful sharp dissection under microscope magnification, the tumor was totally removed. Pathological diagnosis identified a CP of the squamous-papillary variety [Figure 4b1 and b2].
The patient recovered successfully from the surgical procedure, although her panhypopituitarism, diabetes insipidus, and subjective visual disturbance remained unchanged. Complete removal of the lesion was confirmed on postoperative MRI [Figure 5a], with a small defect or breach at the 3V floor that extended to the junction of the optic chiasm and the right optic tract, just at the site where the tumor infiltrated the chiasm [Figure 5b and c].
Follow-up neuro-ophthalmological assessment 1 week after surgery showed some improvement in the patient's visual acuity and visual fields. Visual acuity returned to its prior initial values, from only light perception to 20/60 in the right eye and 20/40 in the left one. A marked improvement of vision in the nasal hemi-field in the left eye was observed as well, although only a partial recovery at the temporal-superior quadrant of the right eye occurred (Figure 2, third perimetry on 8/6/2012). Postoperative OCT conducted at this time, however, showed a reduction in the RNFL thickness in both eyes, with atrophy of the superior wedge in the right eye and a greater degree of atrophy in the temporal wedge in the left eye. At the last visual assessment, six months after surgery, a significant worsening of the visual defect was evidenced on the perimetry (Figure 2, fourth perimetry on 01/21/2013), probably due to degenerative changes of retinal fibers associated with gliotic scarring. This damage was congruent with the postoperative retinal atrophy disclosed on the OCT. No tumor recurrence was demonstrated on the last postoperative MRI, performed 1 year after surgery.