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Isolated amyloid deposition in an extraocular muscle is a rare event but can be a presenting feature of systemic amyloidosis. A 67-year-old woman with an acquired exotropia and hypertropia was found to have unilateral diffuse extraocular muscle enlargement on magnetic resonance imaging. Owing to the progressive nature of her strabismus and the negative laboratory testing for thyroid disease, she underwent an extraocular muscle biopsy that revealed amyloid deposition. Further workup demonstrated a monoclonal gammopathy consistent with systemic amyloidosis. This case demonstrates the need to consider amyloidosis in the differential diagnosis of patients presenting with an atypical acquired strabismus. We review other reports of isolated amyloid deposition in extraocular muscles and its association with systemic amyloidosis, emphasizing the importance of the ophthalmologist in the early recognition of this disease to prevent irreversible, life-threatening end organ damage.

Purpose: To describe the importance of considering vaso-occlusive disease on the differential diagnosis of a patient presenting with amaurosis fugax (AF) and unilateral cotton wool spots (CWS). Observations: A 69-year-old female with history of obesity, hyperlipidemia and recent orthopedic surgery, presented with 3 days of worsening monocular AF and CWS in the right eye. She was diagnosed with antiphosphospholipid syndrome based on positive serologic testing for antiphosphatidylserine IgM, anticardiolipin IgM. The patient was treated with lipid lowering medication, long-term aspirin, and has followed a weightloss and physical therapy program under medical supervision. The CWS resolved and AF symptoms have not recurred. Conclusions and importance: Antiphospholipid syndrome can be considered in the differential diagnosis of patients presenting with AF, assymetric CWS, and/or rapid progression of symptoms.

Intracranial germinomas are typically present in the suprasellar or pineal location, and their origin within the optic nerve or chiasm is extremely rare. We report a 25-year-old woman with an exophytic primary optic chiasm germinoma who underwent partial resection followed by radiation and had no detectable tumor on magnetic resonance imaging at 1-year follow-up.

Background Cerebral venous sinus thrombosis (CVST) is a life-threatening condition that may present with symptoms and signs identical to idiopathic intracranial hypertension (IIH). Both conditions consist of increased intracranial pressure (ICP); however, IIH shows no evidence of contributory intracranial pathology. Oral hormonally based contraceptive usage has been associated with both conditions as well. Because disc edema often occurs in CVST, and IIH and is evident in other sight- and life-threatening conditions such as intracranial mass lesions, neuroimaging and other ancillary testing must be conducted for definitive diagnosis. Case An 18-year-old white woman with IIH previously diagnosed presented with headaches and severe visual loss in the left eye. Bilateral disc edema with macular edema in the left eye (O.S.) was present. Threshold perimetry found bilaterally enlarged blind spots as well as a central scotoma O.S. Her medical history was significant for a right transverse, sigmoid and jugular siphon thrombosis secondary to a hypercoagulable state and associated with her use of oral birth control medication. Subsequent magnetic resonance venography (MRV) found the presence of CVST. Despite anticoagulation therapy and acetazolamide, she had severe, nonresolving papilledema. Treatment with oral prednisone was initiated. She recovered full visual fields and excellent visual acuity. Conclusion Because of the similarity in clinical presentation of CVST and IIH, it is important to differentiate distinguishing characteristics of these diseases for correct diagnosis and prompt treatment.

A 50-year-old healthy woman underwent an uncomplicated elective clipping of a right middle cerebral artery aneurysm via pterional craniotomy. Ophthalmology was consulted urgently in the recovery roombecause of complaints of vision loss andophthalmoplegia in the right eye. On examination, visual acuity was no light perception (NLP) OD and 20/20 OS. Pupils were equal and round, with a 3+ relative afferentpupillarydefect in the right eye. Intraocular pressure was within normal limits in both eyes. There was completeophthalmoplegia in the righteyewithnosigns of restriction on forced ductions and normalmotility in the left eye. Visual field was full to confrontation in the left eye. The right eye also demonstratedmild fullness of theorbit, right cheek skin erythema, traceproptosis, and trace conjunctival chemosis. Posterior examinationwas significant for diffuse retinalwhiteningwith a cherry-red spot in themacula in the right eye (Figure 1A). Therewere noother neurologic deficits identified on examination. Acomputed tomographyscanwithout contrastdidnot showanacute intracranial hemorrhage and demonstrated diffuse enlargement of the right extraocular muscles. Magnetic resonance imaging of the brain and orbits with contrast again showed enlargement and abnormal signal of the extraocular muscles on the right (Figure 1B); there was no evidence of cavernous sinus pathology. Quiz at jamaophthalmology.com A B

Ischemic optic neuropathy occurred in a patient following liposuction. Perioperative anemia and hypotension may be the cause of this complication. Correction of anemia with transfusion improved the hemoglobin and hematocrit but the right eye remained blind. Liposuction should be added to the list of the surgical procedures that may produce ischemic optic neuropathy as an isolated complication.

A patient with advanced AIDS presented with right conjugate gaze palsy and impaired adduction on left gaze (the one-and-a-half syndrome). The responsible pontine lesion involved the ipsilateral abducens nucleus and the adjacent medial longitudinal fasciculus (MLF), as demonstrated by magnetic resonance imaging (MRI). Tuberculosis (TB) was the etiology of the brainstem lesion. The patient had complete recovery after anti-tuberculosis treatment. The nuclear location of the tuberculoma is unusual and the reversal of this neuro-ophthalmologic syndrome is noteworthy.

Objective To determine the incidence of positive neuroradiologic studies in consecutive patients with glaucoma associated with normal intraocular pressure and to compare the psychophysical and clinical characteristics of these eyes with eyes with disc cupping associated with intracranial masses. Design Retrospective case-controlled study. Participants Fifty-two eyes of 29 patients with glaucoma associated with normal intraocular pressure and 44 eyes of 28 control patients with compressive lesions were reviewed. Intervention The medical records of consecutive glaucoma patients with normal intraocular pressure who underwent brain magnetic resonance imaging or computed tomography scanning as part of a diagnostic evaluation between January 1, 1985, and July 1, 1995, were reviewed. A masked reading of optic nerve photographs and visual fields was performed by one observer. A similar analysis was performed on a control group of consecutive patients with nonglaucomatous optic nerve cupping with known intracranial mass lesions. Main outcome measures The neuroradiologic findings, clinical characteristics, optic nerve head appearance, and patterns of visual field loss were compared between groups. Results None of the patients diagnosed with glaucoma had neuroradiologic evidence of a mass lesion involving the anterior visual pathway. Compared to control subjects, patients with glaucoma were older ( P = 0.0001), had better visual acuity ( P = 0.002), greater vertical loss of neuroretinal rim tissue ( P = 0.0001), more frequent optic disc hemorrhages ( P = 0.01), less neuroretinal rim pallor ( P = 0.0001), and more nerve fiber bundle visual field defects aligned at the horizontal midline ( P = 0.0001). Visual acuity less than 20/40, vertically aligned visual field defects, optic nerve pallor in excess of cupping, and age younger than 50 years were 77%, 81%, 90%, and 93% specific for nonglaucomatous cupping associated with compressive lesions, respectively. Conclusions Anterior visual pathway compression is an uncommon finding in the neuroradiologic evaluation of patients with a presumptive diagnosis of normal-tension glaucoma. Younger age, lower levels of visual acuity, vertically aligned visual field defects, and neuroretinal rim pallor may increase the likelihood of identifying an intracranial mass lesion.

A 16-year-old adolescent girl with multiple risk factors for thrombosis presented with acute onset of headache, decreased vision, and papilledema. Evaluation demonstrated cerebral venous thrombosis (CVT) involving the left transverse and sigmoid sinuses and left internal jugular vein. Following bilateral optic nerve sheath fenestration (ONSF), she experienced improvement in vision and resolution of papilledema. In selected cases, ONSF is an effective surgical option for the treatment of papilledema due to CVT after medical treatment has failed.

BACKGROUND: Radiation optic neuropathy (RON) is a rare, unpredictable, late complication of radiotherapy secondary to obliterative endarteritis. Tumor recurrence has to be ruled out by a clinical and neuroradiological examination. METHODS: Five patients with RON were investigated by magnetic resonance imaging (MRI) during 1992. RESULTS: Radiation-induced lesions of the intracranial visual pathways were easily visible on MRI. Without Gadolinium, a sectorial swelling was detectable, which markedly enhanced with Gadolinium. Intracranial optic nerve was affected in 5/5 cases, optic chiasm in 3/5 cases, and optic tract in 2/5 cases. CONCLUSIONS: MRI is the examination of choice when RON is suspected: it will easily delineate the extent of the lesion, and compression/infiltration by a recurrent tumor will be formally ruled out. A segmental swelling of visual pathway with marked Gadolinium enhancement on MRI is highly suggestive of radionecrosis.

Background: Occlusive vasculitis affecting the optic nerve or chiasm is an infrequent delayed complication of radiation treatment. Hyperbaric oxygen (HBO) has been used to treat such a complication...

Purpose: To characterize visual morbidity in giant cell arteritis and to assess prognosis with respect to treatment. Methods: Record review of 185 patients with coded diagnosis of giant cell (cranial) arteritis examined at the Bascom Palmer Eye Institute from January 1, 1980, to January 31, 1993. Results: Forty-five patients with biopsy-proven giant cell arteritis had visual symptoms, and 41 individuals (63 eyes) lost vision. The visual loss was unilateral in 19 patients (46%), sequential in 15 (37%), and simultaneous in 7 (17%). Anterior ischemic optic neuropathy developed in 88% of eyes, visual acuity was 20/200 or worse in 70%, 21% had no light perception, and the majority of field defects in testable eyes, aside from central scotomas associated with loss, showed altitudinal or arcuate patterns. Six patients lost vision during corticosteroid therapy for systemic symptoms of giant cell arteritis, whereas in 39 patients visual symptoms prompted steroid treatment. For visual symptoms, 25 patients received intravenous methylprednisolone, whereas 20 received oral prednisone alone. In the 41 patients with visual loss, vision was unchanged in 20 (49%), it worsened in 7 (17%), and it improved in 14 (34%). Subsequent fellow eye involvement was observed only with oral therapy, and a greater percentage of patients (9/23 [39%] versus 5/18 [28%]) improved after intravenous treatment. Conclusions: In the authors' series, patients with visual loss due to giant cell arteritis had a 34% chance for some improvement in visual function after corticosteroid treatment. Intravenous therapy may diminish the likelihood of fellow eye involvement and was associated with a slightly better prognosis for visual improvement.

BACKGROUND Systemic lupus erythematosus (SLE) is a multisystemic inflammatory disease of unknown etiology. Physiopathology includes small vessel occlusion and auto-antibody production. Neuro-ophthalmic complications can be detected in 10-30% of SLE cases. Further, some patients can present with neuro-ophthalmic complications prior to diagnosis of SLE. PATIENTS AND METHODS We report seven cases of neuro-ophthalmic complications of SLE demonstrating lesions from the retina to the brain. The other possible manifestations of SLE will be reviewed. RESULTS Two cases were not yet diagnosed with SLE when neuro-ophthalmic disease occurred. Anti-double stranded DNA antibodies were detected at a very high titer, suggesting SLE, later confirmed by rheumatologists. CONCLUSIONS Ophthalmologists should be aware of the unusual patient presenting with a neuroophthalmic disorder prior to the diagnosis of SLE. In such cases, autoantibodies should be sought. Antinuclear antibodies are very sensitive but non specific for SLE. Anti-double stranded DNA antibodies are specific for SLE and elevated titer should raise the suspicion of undiagnosed SLE.

We report 2 patients who had eyelid retraction and eyelid lag with minimal impairment of vertical gaze. In both patients, magnetic resonance imaging demonstrated a circumscribed unilateral lesion immediately rostral and dorsal to the red nucleus involving the lateral periaqueductal gray area. Our clinical and radiological findings support the existence of a premotor eyelid control center in the region of the nucleus of the posterior commissure.

After transsphenoidal resection of a pituitary (or other) tumor, the remaining intrasellar cavity, and sphenoid sinus are usually packed with exogenous fat or muscle to prevent cerebrospinal leak and prolapse of the optic chiasm into an empty sella. We treated two patients in whom chiasmal compression occurred postoperatively because of packing of fat. In one patient, the expected visual improvement in the postoperative period was suboptimal. The subsequent removal of fat resulted in total visual recovery. In the other patient, chiasmal compression persisted from intrasellar fat and residual tumor. Iatrogenic compression of the optic nerves or chiasm should be considered in all patients in whom visual recovery is incomplete.

This Hoyt lecture is composed of 2 topics. First, a series of patients with idiopathic intracranial hypertension (IIH) is presented, emphasizing the importance of magnetic resonance venography (MRV). Study of the cerebral venous sinuses in IIH may demonstrate focal stenosis or venous gaps and represent a manifestation of elevated intracranial pressure. Conversely, the clinical picture of IIH may occur following cerebral venous sinus thrombosis, and MRV may be essential in establishing this diagnosis. In the future, evaluation of flow in the cerebral venous sinuses may play an important role in determining the potential for visual failure. Second, I will review patients with visual cognitive changes, which often go unrecognized. These patients suffer from visuoperceptual disturbances, recognizing parts of visual scenes but not the entire picture and are unable to comprehend their visual environment. These findings are often part of the syndrome of posterior cortical atrophy characterized by parieto-occipital atrophy, enlargement of the atrial portion of the ventricular system, and diminished metabolic activity in the posterior portion of the brain demonstrated with positron emission tomography.

Hodgkin's disease is a rare cause of infiltrative optic neuropathy, which typically evolves late in the disease course. We managed an unusual case of isolated optic neuropathy in a 21-year-old man occurring during clinical remission from Hodgkin's disease. Radiotherapy and treatment with high-dose systemic corticosteroids resulted in dramatic improvement in vision. Even without other evidence of recurrent disease, acute-onset optic neuropathy in a patient with a history of a lymphoproliferative disorder should raise the question of a reemergence of the malignancy.

Dural sinus hypertension from cerebral venous outflow impairment is a cause of pseudotumor cerebri. The authors documented six such patients: two with unilateral neck dissection, one with surgical ligation of the dominant sigmoid sinus, two with thrombosed central intravenous catheterization, and one with dural sinus thrombosis. The site of cerebral venous outflow obstruction was variable and identified in three patients with computed tomography, conventional magnetic resonance imaging, magnetic resonance angiography, and/or angiography. Magnetic resonance angiography used in two patients characterized the venous flow pattern and identified the site of obstruction, confirming magnetic resonance angiography as an effective noninvasive blood flow technique in diagnosing and following these patients. Three patients were treated successfully with medical therapy and one patient with optic nerve fenestration. The two patients with thrombosed central venous catheters had serious systemic illnesses and suffered permanent visual loss.

A patient with typical pituitary apoplexy with documented intralesional hemorrhage and spontaneous resolution is presented. There was no evidence of a tumor at a 3-month follow-up.

We present two cases of delayed optic nerve complications following proton beam radiotherapy. Patient 1 received radiotherapy after surgery for clival chordoma and developed sequential radiation optic neuropathy at 5 and 9 months. Patient 2 developed optic nerve hemorrhage post radiotherapy for optic nerve sheath meningioma. These two cases of blindness demonstrate the risks associated with proton beam radiotherapy.

Three patients with delayed radiation optic neuropathy after radiation therapy for parasellar neoplasms underwent magnetic resonance imaging. The affected optic nerves and chiasms showed enlargement and focal gadopentetate dimeglumine enhancement. The magnetic resonance imaging technique effectively detected and defined anterior visual pathway changes of radionecrosis and excluded the clinical possibility of visual loss because of tumor recurrence.

Thirteen patients with delayed radiation injury to the optic nerves and chiasm were treated with hyperbaric oxygen (HBO) and corticosteroids. These patients experienced painless, abrupt loss of vision in one (6 patients) or both (7 patients) eyes between 4 and 35 months after receiving radiation doses of at least 4500 cGy to the region of the chiasm. Diagnostic evaluation including neuro-imaging and lumbar puncture showed no recurrent tumor and no other cause for visual loss. No patient's vision improved during treatment or follow-up lasting between 1 and 4 years. There were no serious complications of treatment.

Purpose Severe visual acuity loss associated with pseudotumor cerebri is usually caused by chronic optic disk edema or a retinal abnormality. Method We treated a woman, with known pseudotumor cerebri treated with a lumboperitoneal shunt, who developed acute pallid optic disk swelling and visual acuity of R.E.: no light perception and L.E.: 20/70 in association with lumboperitoneal shunt failure. There were no contributory retinal lesions. Results The patient underwent optic nerve sheath fenestration and lumboperitoneal shunt revision. Visual acuity improved to 20/20 in both eyes. The papilledema resolved. Conclusion The severe sudden visual loss was attributed to axoplasmic stasis and optic nerve ischemia associated with a sudden rise in intracranial pressure.

Purpose To review the clinical characteristics, prevalence, and severity of retinopathy in diabetics with cranial nerve (CN) 3, 4, and/or 6 palsies, and to determine the relationship between type and duration of diabetes mellitus (DM), presence of retinopathy, and occurrence of CN palsy. Design Retrospective, comparative cohort study. Participants Chart reviews of 2229 patients with CN 3, 4, and/or 6 palsies were performed at the Bascom Palmer Eye Institute (BPEI) from January 1991 through December 1997 and at the Dean A. McGee Eye Institute (DMEI) from January 1994 through July 2001. A total of 306 patients qualified for the study group. The Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) was used as a control. Methods Demographic and clinical data were extracted to determine characteristics of patients with diabetic ophthalmoplegia. The subsets of data regarding type of DM and level of diabetic retinopathy in the study population were compared with the WESDR control data for statistical analysis. Main outcome measures The prevalence of diabetic retinopathy in patients with diabetic ophthalmoplegia. Results Of 2229 patients at both institutions with ocular motor CN palsy, 306 (13.7%) were associated with DM. The frequency of CN involvement was 6 (50.0%), 3 (43.3%), and 4 (6.7%). There was a total of 12 patients (3.9%) with consecutive palsies and 8 patients (2.6%) with simultaneous palsies (5 unilateral and 3 bilateral). At both institutions, the prevalence of retinopathy controlling for duration of DM was lower in both insulin-dependent DM (IDDM) and non-IDDM (NIDDM) type II diabetics as compared with controls (BPEI, P = 0.009 and P = 0.005; DMEI, P = 0.004 and P = 0.29). When data from both locations were combined, the difference was even more significant (IDDM, P = 0.001 and NIDDM, P = 0.006). There were no significant differences between the two institutions in gender, type or duration of DM, age at presentation, or frequency of CN involvement. Conclusions Diabetic ophthalmoplegia most commonly involves CN 3 and 6, with relative sparing of CN 4. Multiple cranial nerves are affected simultaneously in 2.6% of cases, and consecutive palsies occurred in 3.9% of cases. Type II diabetics with ocular motor CN palsy have significantly less diabetic retinopathy than do controls. This may imply a different pathophysiologic mechanism for these two microvascular complications of DM.

PURPOSE: To report infraorbital nerve dysfunction after laser in situ keratomileusis. DESIGN: Observational case report. METHODS: Neuro-ophthalmologic examination with brain and orbital magnetic resonance imaging (MRI) and orbital computed tomography (CT). RESULTS: During laser in situ keratomileusis, two healthy women, aged 42 and 46 years, experienced acute onset of sharp ipsilateral cheek pain. Both cases occurred during manipulation of the eyelid speculum. Postoperatively, ipsilateral numbness and tingling or pain of the upper cheek was reported, and examination showed decreased sensation in the distribution of the infraorbital nerve. In both cases, brain and orbit MRI and orbit CT were normal. Both patients were managed medically. In one patient, mild symptoms persisted 1 year postoperatively, and in the second patient, moderate discomfort persisted 8 months postoperatively. CONCLUSION: Infraorbital nerve palsy is a potential complication of laser in situ keratomileusis. Symptoms improve but may persist.

The clinical course of four patients with visual loss in the postpartum period due to acute optic neuritis is described. Factors that disclosed the underlying etiology and expression of disease are discussed. The clinical records of four women examined and managed for visual loss after uncomplicated pregnancies and term deliveries were reviewed. Neurodiagnostic examination, treatment modalities, and outcomes were assessed. These four women with varied and confounding medical histories, all with optic neuropathy, eventually were demonstrated to harbor demyelinating disease. Although visual loss in the postpartum period evokes differential diagnostic considerations, the authors' experience suggests that puerperal immune-mediated changes are responsible for activation of optic neuritis associated with relapsing multiple sclerosis.

We report two patients with unique homonymous hemianopias from occipital lobe infarctions. One patient had vertical meridian sparing, and the other displayed horizontal meridian sparing. MRI correlation with the visual field defects confirmed that the vertical hemianopic meridian was represented along the border of the calcarine lips, and the horizontal meridian lies at the base of the calcarine banks deep within the calcarine fissure.

A 66-year-old woman presented with a 3-year history of predominantly right-sided blepharospasm and a 1-year history of progressive predominantly left-sided hemiparkinsonism manifested by a left upper extremity resting tremor and left-sided bradykinesia. Magnetic resonance imaging of the brain revealed a large right mesencephalic cyst with mass effect. Positron emission tomography revealed bilateral striatal hypometabolism consistent with nigrostriatal dopaminergic dysfunction. The association of predominantly ipsilateral blepharospasm and predominantly contralateral hemiparkinsonism is very rare, and its association with a posterior fossa space-occupying lesion has been reported only once. This is the second report of such an association and the first description of adult-onset symptomatology.

A 15-year-old boy had onset of unilateral facial weakness. A few days later, he experienced mild vertigo, double vision, and headache. Examination confirmed a peripheral right seventh nerve weakness in addition to an internuclear ophthalmoplegia. The neurologic features suggested a pontine glioma. A T2-weighted MRI scan revealed demyelinating lesions in the pons and in several areas of the cerebrum, including the periventricular region. Subsequent history revealed that he had been diagnosed with Lyme arthritis 7 years earlier while living in Connecticut. The radiographic studies favored a diagnosis of multiple sclerosis. However, studies of blood and cerebrospinal fluid established a diagnosis of Lyme neuroborreliosis.

Neuroimaging with nuclear medicine techniques permits assessment of brain function by measurement of metabolism or blood flow. Such studies complement the anatomic information derived from computed tomography (CT) or magnetic resonance imaging (MRI). We describe two patients with occipital lesions who were initially diagnosed with functional visual loss. Neither CT scan nor MRI adequately demonstrated the source of visual dysfunction; however, single proton emission tomography (SPECT) scanning in a patient with carbon monoxide poisoning and positron emission tomography (PET) scanning in a patient with post-hypoxic delayed encephalopathy were helpful in confirming the organic substrate of their visual impairment. Functional imaging techniques such as SPECT and PET should be considered in patients with suspected cortical visual loss and normal CT or MR scans.

Ten patients with migraine developed persistent positive visual phenomena lasting months to years. The complaints were similar in their simplicity and involvement of the entire visual field and usually consisted of diffuse small particles such as TV static, snow, lines of ants, dots, and rain. Neurologic and ophthalmologic examinations were normal, and EEGs were normal in eight of eight patients tested. MRI was normal in all patients except one who had nonspecific biparietal white matter lesions and another with a small venous angioma. Treatment of this unusual complication of migraine was unsuccessful.

Objective: To determine the efficacy of optic nerve sheath fenestration in eyes with the progressive form of common anterior ischemic optic neuropathy. This investigation complements a previously reported initial series of 26 similar patients. Patients and Methods: Optic nerve sheath fenestrations were performed in 21 eyes for treatment of common (nonarteritic) ischemic optic neuropathy with documented progressive deterioration of visual function. All patients underwent thorough preoperative and postoperative ocular evaluations by the Neuro-Ophthalmology Service at the Bascom Palmer Eye Institute, Miami, Fla. Results: During a mean follow-up of 22.5 weeks (range, 3 to 104 weeks), results were as follows: visual acuity increased by 2 or more lines on the Snellen chart in two eyes (9.5%; the combined improvement rate for the two series was 14.9%); visual acuity decreased by 2 or more lines in two eyes (9.5%). Conclusions: Data from this series of 21 surgical procedures indicate no beneficial effect on visual morbidity in cases of common ischemic optic neuropathy and confirm the generally poor visual outcome implied from the results of optic nerve sheath decompression in our initial series. Based on this experience with a total of 47 eyes, we have discontinued optic nerve sheath decompression as a form of therapy for ischemic optic neuropathy.

We report three patients with chronic headaches and optic neuropathy due to widespread meningeal thickening shown on enhanced MRI; all had biopsy-proven intracranial pachymeningitis (fibrosclerosis of the meninges). Two patients had bilateral optic neuropathy, elevated CSF protein, and polyclonal serum hypergammaglobulinemia. They developed temporal lobe cortical necrosis or sagittal sinus thrombosis, presumably due to compromised dural venous drainage from extensive meningeal fibrosis. The other patient had multiple cranial nerve palsies and unilateral optic neuropathy with normal CSF. Corticosteroid therapy improved visual function in all three patients, although all had persisting visual deficits. Gadolinium-enhanced MRI was essential in identifying meningeal inflammation and locating suitable biopsy sites.

Homonymous visual field defects are rare in patients with MS and are usually caused by large lesions in the white matter of the posterior optic radiations and visual cortex. The postulate of Holmes and others, early this century, that optic radiation lesions could produce quad-rantic defects has recently been questioned. We report the full recovery of a patient with probable MS who presented with congruous quadrantanopia from a small white matter lesion in the contralateral trigone area.

Clinical data and fundus fluorescein angiograms were analyzed from 35 patients with acute (onset less than four weeks) anterior ischemic optic neuropathy. Nineteen of the 35 patients (54%) had nonarteritic disease, and 16 patients (46%) had giant cell arteritis confirmed by biopsy. Patients with arteritis had higher erythrocyte sedimentation rates, larger cup/disk ratios, and delayed fluorescein dye appearance and choroidal filling times. Three additional patients with cranial arteritis confirmed by biopsy, but without visual loss, had angiographic characteristics similar to patients with arteritic ischemic neuropathy. We consider fluorescein angiography a valuable diagnostic adjunct in identifying patients with giant cell arteritis.

• Optic nerve sheath fenestration was performed in 26 eyes for treatment of the progressive type of common (nonarteritic) anterior ischemic optic neuropathy. During a mean follow-up period of 21 weeks (range, 6 to 52 weeks), results were as follows: visual acuity increased by two or more lines on the Snellen chart in 7 eyes; visual acuity decreased by two or more lines in four eyes; some regression of visual field defects occurred in six eyes, including two eyes in which acuity also improved. These results, attributed to surgical decompression, do not exceed the spontaneous recovery rates reported in the literature pertaining to nonarteritic anterior ischemic optic neuropathy and fail to substantiate the sanguine visual outcome in recently reported series of patients undergoing optic nerve sheath decompression.

We reviewed retrospectively 114 prednisone dose reduction attempts in 63 myasthenic patients. Dose reduction was considered successful if a patient remained asymptomatic for more than 1 year on no prednisone or a stable low dose of prednisone. Successful dose reduction attempts were more common in patients taking azathioprine, but thymectomy did not influence taper outcome. Slower rate of dose reduction and higher ending dose of prednisone improved the chance of success.

Purpose We examined a 28-year-old woman who developed incongruous binasal and bitemporal visual field defects one week after having a febrile gastroenteritis characterized by severe diarrhea while traveling in Mexico. Methods The patient was treated with intravenous methylprednisolone sodium succinate, 1 g daily for three days, followed by an eight-week course of oral prednisone. Results Neuroradiologic examination demonstrated bilaterally increased signal intensity within the lateral geniculate bodies. Cerebrospinal fluid analysis disclosed isolated protein increase. Conclusion Severe diarrhea may be associated with an aseptic bilateral lateral geniculitis resulting in hourglass-shaped visual fields. Corticosteroid therapy may provide mild improvement.

A 42-year-old woman with a 6-year history of diabetes insipidus and progressive hypersomnolence presented with visual loss. Neuroimaging showed infiltration in the hypothalamus, the optic nerve, and the chiasm, as well as multiple lesions in other areas of the brain parenchyma. Biopsy showed Langerhans cell histiocytosis. This is an unusual presentation of Langerhans cell histiocytosis, involving the visual pathways without manifestations outside of the central nervous system. The differential diagnosis and the magnetic resonance imaging findings will be discussed.