Syndrome simulating pseudotumor cerebri caused by partial transverse venous sinus obstruction in metastatic prostate cancer.

PURPOSE: To report a case of partial transverse venous sinus obstruction causing a syndrome resembling pseudotumor cerebri. METHOD: Case report. A 61-year-old man developed decreased vision, bilateral papilledema, and a highly increased cerebrospinal fluid opening pressure. Brain magnetic resonance imaging (MRI) disclosed a small, extra-axial mass near the torcula, which was dismissed as an incidental meningioma because cerebral angiography showed sinus patency. RESULTS: The patient's vision worsened. Biopsy of the enlarging mass disclosed metastatic prostate cancer. After radiation therapy, the mass shrank, magnetic resonance angiography disclosed reopening of the transverse sinuses, and papilledema resolved, but visual fields remained severely compromised. CONCLUSION: Partial blockage of the dural venous sinus by a small mass near the torcula can cause a sufficient increase in intracranial pressure to produce vision-threatening papilledema.

The impact of the optic neuritis treatment trial on the practices of ophthalmologists and neurologists.

OBJECTIVE: To determine whether the Optic Neuritis Treatment Trial (ONTT) results have altered the practice patterns of ophthalmologists and neurologists. DESIGN: Mail survey. PARTICIPANTS: A random sample of 987 ophthalmologists and 900 neurologists practicing in the United States were mailed a questionnaire that inquired into decision-making with regard to management of optic neuritis before and after the publication of the ONTT results. MAIN OUTCOME MEASURES: Responses received from 202 ophthalmologists and 244 neurologists, a response rate of 47%. RESULTS: Following the ONTT reports, nearly all ophthalmologists and neurologists have reduced their use of oral prednisone alone, substituting a regimen that includes intravenous methylprednisolone. A large proportion of practitioners in both specialties mistakenly believe that intravenous methylprednisolone treatment improves final visual outcome. Only 7% of neurologists and 36% of ophthalmologists (P = 0.0001) are adhering to the ONTT suggestion to use magnetic resonance imaging as a basis for initiating treatment. CONCLUSIONS: The ONTT has led to a dramatic reduction in the use of oral prednisone without a preceding course of intravenous methylprednisolone in the treatment of acute optic neuritis. Ophthalmologists and neurologists have changed some of their practices without fully understanding the results of the ONTT.

Brain biopsy in primary angiitis of the central nervous system.

To determine the yield of brain biopsy and the predictive value of clinical features and ancillary studies, we retrospectively analyzed hospital chart data from 61 consecutive patients suspected of having primary angiitis of the CNS (PACNS). Biopsies disclosed PACNS in 22 (36%), alternative diagnoses in 24 (39%), and no diagnosis in 15 (25%). Clinical indicators and angiography were not useful predictors of PACNS. Brain biopsy should be the primary diagnostic tool in this setting because of the poor reliability of other indicators and because of the high yield of alternative diagnoses requiring different management.

Minocycline treatment and pseudotumor cerebri syndrome.

PURPOSE: To demonstrate the association between minocycline treatment and development of the pseudotumor cerebri syndrome. METHODS: A retrospective study was conducted of 12 patients from five neuro-ophthalmic referral centers who developed pseudotumor cerebri syndrome after being treated with standard doses of minocycline for refractory acne vulgaris. The main outcome measures included resolution of headaches, transient visual obscurations, diplopia, papilledema, and visual fields static thresholds after withdrawal of minocycline and treatment for increased intracranial pressure. RESULTS: Nine (75%) of the 12 patients developed symptoms of the pseudotumor cerebri syndrome syndrome within 8 weeks of starting minocycline therapy; six were not obese. Two patients developed symptoms only after a year had elapsed because of commencement of treatment with minocycline. One patient was asymptomatic, and pseudotumor cerebri syndrome was diagnosed by finding papilledema on routine examination 1 year after minocycline was started. None of the patients developed recurrences for at least 1 year after the discontinuation of minocycline and treatment for increased intracranial pressure, but three (25%) of the 12 patients had substantial residual visual field loss. CONCLUSION: Minocycline is a cause or precipitating factor in pseudotumor cerebri syndrome. Although most patients have prominent symptoms and are diagnosed promptly, others are asymptomatic and may have optic disk edema for a long period of time before diagnosis. Withdrawal of minocycline and treatment for increased intracranial pressure lead to resolution of the pseudotumor cerebri syndrome, but visual field loss may persist.

The effectiveness initiative. II: The spectrum of effectiveness research.

Effectiveness research aims to base medical decision making more on rigorous evidence than on intuition and anecdote. The methods used to generate new data include, in order of decreasing rigor, clinical trials, observational studies, claims data analysis, and anecdotal studies. The methods that synthesize existing data include unstructured literature reviews, consensus development, meta-analysis, and decision modeling. Cost minimization, cost-effectiveness, and cost-benefit analyses are formal methods of incorporating the economic impact of alternative medical interventions.

The effectiveness initiative. I. Medical practice guidelines.

We examined the impact of the "effectiveness initiative" and medical practice guidelines on the practice of ophthalmology. The effectiveness initiative asserts that much of current medical practice is unnecessary or harmful, too costly, and unresponsive to patient desires. It promotes more critical review of the medical literature, research on outcomes, and stringent practice guidelines. Whereas current practice guidelines are helpful in codifying accepted procedures, they tend to sanction interventions of unproved value. Future guidelines will probably reject unproved interventions, especially if they are expensive. Although such guidelines may limit physicians' freedom of choice, they may protect them against capricious malpractice claims and unreasonable patient expectations.

Ischemic optic neuropathy after lumbar spine surgery.

OBJECTIVE: Study of clinical features of ischemic optic neuropathy (ION) developing as a complication of multilevel lumbar spine surgery. DESIGN: Review of all cases of ION that developed within 2 weeks of spine surgery at two academic institutions from 1990 to 1992, and a review of adequately reported cases of ION after other non-ophthalmic procedures. RESULTS: Four new cases are reported in patients who ranged in age from 41 to 65 years. All four had undergone uneventful but prolonged (8 to 9 hours) spine surgery, during which blood pressure was deliberately maintained between 85 and 100 mm Hg systolic and 45 to 65 mm Hg diastolic to reduce bleeding. Hemoglobin values fell 30 to 78 g/L during surgery. Arteriosclerotic risk factors, including systemic hypertension, diabetes, coronary artery disease, and smoking, were present in three cases. There was no evidence of orbital soft-tissue injury, retinal artery occlusion, or other neurologic deficits. The combination of hypotension and anemia has been noted in most of the 30 previously well-documented cases of ION after other non-ophthalmic procedures. CONCLUSIONS: Multilevel lumbar laminectomy should be added to the list of procedures that may produce ION as an isolated complication. Deliberate hypotension maintained for long operative periods in patients with arteriosclerotic risk factors may be the cause.

Integrative agnosia following progressive multifocal leukoencephalopathy.

A 43 year-old man with presumed progressive multifocal leukoencephalopathy developed difficulty recognizing objects and faces in the presence of adequate visual acuity and visual fields. His copying and matching of line drawings was intact, suggesting that his agnosia was associative. However, he had difficulty perceiving overlapping forms and drawings of single objects as integrated wholes. Unlike control subjects, he made fewer errors identifying silhouettes compared to line drawings with internal details. These alterations, together with his feature-by-feature descriptions of objects and copying, suggest that his agnosia was due to a disturbance in integrating local form features, as described by Riddoch and Humphreys (1987). This interpretation is supported by the findings that his tactile recognition and semantic and structural knowledge of the objects he could not identify visually were intact. Furthermore, his deficient performance in categorical matching of photographs to objects was dependent upon the perceptual complexity of the photographs. Similar deficits in early form processing described by other investigators are discussed.

Varied clinical spectrum of necrobiotic xanthogranuloma.

Four cases are presented that illustrate a wide spectrum of ophthalmologic and systemic features of necrobiotic xanthogranuloma (NXG). Case 1 initially had signs of Cogan syndrome, and then developed chronic lymphocytic leukemia. Case 2, the first case of NXG to undergo autopsy, had progressive cicatricial lid retraction and corneal perforation. Case 3 had a more typical presentation of diplopia and blepharoptosis caused by orbital and periorbital infiltrative masses. Case 4 had nondeforming periocular skin lesions over a 6-year period. In all four cases, the diagnosis was made on the basis of characteristic histopathologic and laboratory findings. Although the cause of NXG is still obscure, in many cases it appears to be a forerunner of lymphoproliferative diseases.

Visual loss in tuberous sclerosis.

Of 11 patients with tuberous sclerosis complex (TSC) treated from 1980 to 1990 for obstructive hydrocephalus secondary to subependymal giant-cell astrocytoma, four had adequate documentation to determine visual outcome. Despite surgical relief of elevated intracranial pressure in all cases, two patients sustained further visual loss. In one patient, visual loss was arrested, and in one patient, it was prevented. Although hydrocephalus is uncommon in TSC, its effects on the optic nerves are serious and eventually irreversible. Because TSC patients may not be able to express early symptoms of increased intracranial pressure, periodic ophthalmologic examination and brain imaging may be advisable when a subependymal lesion has been identified.

Pupillary and electroretinographic abnormalities in a family with neuronal intranuclear hyaline inclusion disease.

Abnormal pupillary function and a severely depressed electroretinogram were found in four members of a family with neuronal intranuclear hyaline inclusion disease, an idiopathic degenerative disorder that involves the central and peripheral nervous systems. Symptoms were limited to the gastrointestinal system and consisted principally of abdominal pain, constipation, and severe weight loss. The discovery of light-fixed pupils in the propositus led to the first antemortem diagnosis by rectal biopsy in two generations of this family. Abnormalities of gastrointestinal motility and pupillary reactions constituted the only objective evidence of autonomic dysfunction; the abnormal electroretinogram was the only evidence of central nervous system dysfunction.

Angle-closure glaucoma as initial presentation of myelodysplastic syndrome.

A 57-year-old man presented with proptosis of the right eye and findings consistent with bilateral angle-closure glaucoma. Subsequent evaluation revealed severe bilateral uveal effusions and associated nonrhegmatogenous retinal detachments, which were felt to be related to orbital pseudotumour and associated scleritis. Hematologic studies were consistent with a diagnosis of myelodysplastic syndrome. Although myelodysplastic syndrome has been reported in one patient with orbital inflammation and myositis, to our knowledge ciliochoroidal effusion and secondary angle closure have not previously been reported in myelodysplastic syndrome.

Visual outcome in cystic craniopharyngiomas treated with intracavitary phosphorus-32.

Seven patients with cystic craniopharyngiomas were treated with stereotactic instillation of radioactive phosphorus-32 (32P). Five patients had been previously treated with various combinations of surgery and external beam irradiation, whereas two had the 32P instillation at a primary therapy. Visual acuity improved in 13 eyes and remained stable in 1. Visual fields normalized in three patients, improved in two, and remained stable in two. Two patients received single treatments with 32P, whereas five required multiple instillations for recurrent cyst expansion.

Bilateral optic nerve compression as a mechanism for the Foster Kennedy syndrome.

An 11-year-old boy with a juvenile nasopharyngeal angiofibroma developed optic disc pallor in one eye and optic disc edema in the other eye (Foster Kennedy Syndrome [FKS]). The mechanism was believed to be bilateral, asymmetric optic nerve compression. Review of the 36 previously reported cases of FKS revealed that 12 cases (33%) were probably also caused by bilateral optic nerve compression. Only eight (22%) of the cases satisfied Foster Kennedy's original hypothesis for the pathogenesis of his syndrome, namely, direct compression of one optic nerve causing atrophy and increased intracranial pressure causing contralateral papilledema. In 15 (41%) reported cases of FKS, descriptions were inadequate to determine a mechanism, while two (5%) were probably caused by long-standing increased intracranial pressure without direct optic nerve compression. The authors believe that as sophisticated imaging permits earlier diagnosis and more precise localization, most future cases of FKS caused by mass lesions will be found to result from bilateral direct optic nerve compression.

Power spectral analysis of visual evoked potentials in multiple sclerosis.

Power spectral analysis (PSA) was performed on the visual evoked potentials (VEPs) to counterphased checkerboard stimuli from 98 eyes in 49 patients with multiple sclerosis (MS) and 54 eyes of 27 normal volunteers. Attenuation of high frequency components of the transient visual evoked potential was found in 53% of MS patients and 4% of controls. Loss of high frequency components was poorly correlated with prolonged latency (r = 0.346). The consideration of both PSA and latency of the VEP increased the percentage of MS patients exhibiting visual pathway conduction abnormalities from 61% to 86%. The use of PSA in the diagnosis of MS is useful in increasing detection especially in cases where deformed waveforms preclude a reliable estimation of latency.