Judith E. A. Warner

A Comparison of Idiopathic Intracranial Hypertension With and Without Papilledema

Objective.— To compare clinical features, visual characteristics, and treatment of idiopathic intracranial hypertension patients with and without papilledema.

Vitamin A in the cerebrospinal fluid of patients with and without idiopathic intracranial hypertension.

We quantified vitamin A in the cerebrospinal fluid of patients with idiopathic intracranial hypertension, elevated intracranial pressure of other causes and normal intracranial pressure. Vitamin A could be detected by high‐pressure liquid chromatography in most of the specimens. There was a significantly higher level of vitamin A in the cerebrospinal fluid of some patients with idiopathic intracranial hypertension. Vitamin A toxicity may play a role in the pathogenesis of idiopathic intracranial hypertension.

Retinol-binding protein and retinol analysis in cerebrospinal fluid and serum of patients with and without idiopathic intracranial hypertension.

Background: Several studies have implicated vitamin A-related compounds in the pathogenesis of idiopathic intracranial hypertension (IIH). The goal of this study was to compare cerebrospinal fluid (CSF) and serum concentrations of retinol and retinol-binding protein (RBP) in subjects with and without IIH. Methods: CSF and serum samples were collected from 87 subjects. The study population was composed of subjects with IIH (IIH group, n = 28), subjects with non-IIH neurologic conditions (neurology controls, n = 42), and subjects undergoing preoperative lumbar puncture but with no known neurologic conditions (anesthesia controls, n = 17). RBP levels (nM) were determined using radial immunodiffusion, and retinol levels (nM) were determined using high-performance liquid chromatography. Results: The retinol/RBP ratio was greater in CSF than in serum, especially in subjects with IIH. Conclusions: The finding of increased levels of unbound retinol in the CSF of subjects with IIH provides further evidence that vitamin A may be involved in the pathogenesis of IIH. Comparative statistical analyses revealed multivariate relationships that demonstrate the need to further investigate correlations between vitamin A and RBP levels in CSF and serum.

FL-41 Tint Improves Blink Frequency, Light Sensitivity, and Functional Limitations in Patients with Benign Essential Blepharospasm

OBJECTIVE The objective of these 2 studies was to assess the efficacy of FL-41-tinted lenses in the treatment of benign essential blepharospasm (BEB). DESIGN A randomized crossover study and a randomized crossover case-control study. PARTICIPANTS The first study included 30 subjects with BEB. The second study included 26 subjects with BEB and 26 controls. METHODS For the first study, subjects were randomized to wear either FL-41 or gray-tinted lenses for 2 weeks. After a 2-week washout period, the other lens was worn for 2 weeks. Questionnaires were completed at baseline, after the first lens, and after the second lens. In the second study, surface electromyography (EMG) was used to measure blink frequency, duration, and force while subjects read and wore FL-41, rose, or gray-tinted lenses. MAIN OUTCOME MEASURES Questionnaires were used to assess perceptions of light sensitivity and the effect of light sensitivity on activities of daily living (ADL). EMG was used to measure blink frequency, duration, and force. RESULTS Most participants observed improvement while wearing both FL-41 and gray-tinted lenses. FL-41-tinted lenses provided superior improvement in the areas of reading, fluorescent light sensitivity, overall light sensitivity, blepharospasm frequency, and blepharospasm severity. FL-41 lenses reduced mean blink rate compared with both rose and gray-tinted lenses, and reduced eyelid contraction force compared with rose-tinted lenses. CONCLUSIONS FL-41 lenses provided both subjective and objective benefit to subjects with BEB. Physicians should consider recommending this noninvasive and inexpensive lens tint to patients with BEB. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.

A novel method for screening the multifocal electroretonogram in patients using hydroxychloroquine.

Purpose: To evaluate retinal function in patients on hydroxychloroquine using multifocal electroretinography. Methods: A retrospective chart review was performed for 23 patients (46 eyes) on hydroxychloroquine therapy and referred for multifocal electroretinogram (mfERG) testing. Duration of treatment, daily hydroxychloroquine dose, visual acuity, fundus examination, color vision testing, Amsler grid testing, visual field examination, and fluorescein angiography results were obtained when available. Multifocal electroretinogram response amplitudes were calculated for the central and paracentral regions and compared with previously published normal values. The central and paracentral regions of the mfERG color difference plot, which assigns colors to localized areas of the mfERG based on deviation from normal, were assessed using a novel Color Difference Plot Scoring System which relies on the color pattern observed within each region. Results: Ninety-two regions were assessed for response amplitudes, 31 of which showed a depressed response amplitude. Of the 17 eyes which had at least one region with a depressed response amplitude, clinical examination findings were relatively benign. Color difference plot scoring showed strong agreement with response amplitude, with a Color Difference Plot Scoring System score of 2 or 3 showing 93.55% sensitivity and 60% specificity for a depressed response amplitude. Interrater reliability of the scoring system as measured by Kendall’s W coefficient of concordance was 0.6484 (P < 0.00001). Conclusion: The mfERG appears to be able to detect decreased retinal function in hydroxychloroquine patients with normal clinical examinations, and may be useful in identifying patients that require close monitoring for the development of clinically relevant toxicity. The Color Difference Plot Scoring System may be used as a tool to aid in the interpretation of results of the mfERG in the clinic setting.

Recurrent chiasmal apoplexy due to cavernous malformation

We report a case of chiasmal apoplexy due to a cavernous malformation (CM). Surgery was delayed because of the patients advanced pregnancy, and nearly complete recovery of vision occurred spontaneously. Recurrent hemorrhage prompted surgical extirpation. The patient was left with a residual deficit. The literature pertaining to chiasmal apoplexy and CMs is reviewed. Nearly half of the reported cases of chiasmal CM had recurrent hemorrhages. The co-occurrence of hemorrhage from CM and pregnancy is too rare to merit any conclusions about cause and effect.

Chronic migraine is associated with reduced corneal nerve fiber density and symptoms of dry eye

We used in vivo corneal confocal microscopy to investigate structural differences in the sub‐basal corneal nerve plexus in chronic migraine patients and a normal population. We used a validated questionnaire and tests of lacrimal function to determine the prevalence of dry eye in the same group of chronic migraine patients. Activation of the trigeminal system is involved in migraine. Corneal nociceptive sensation is mediated by trigeminal axons that synapse in the gasserian ganglion and the brainstem, and serve nociceptive, protective, and trophic functions. Noninvasive imaging of the corneal sub‐basal nerve plexus is possible with in vivo corneal confocal microscopy.

Immunohistochemical evidence of inducible nitric oxide synthase and nitrotyrosine in a case of clinically isolated optic neuritis

Background: Optic neuritis (ON) is a demyelinating inflammation of the optic nerve that may occur as an isolated disease or related to multiple sclerosis (MS). There is little evidence of whether the immunohistochemistry of ON resembles that of typical cerebral MS lesions. Methods: Pathologic optic nerves were obtained from a patient who died of causes unrelated to ON after clinical recovery from clinically isolated ON. Normal control optic nerves were obtained from an eye bank. Normal and pathologic tissues were probed with antibodies to pathologic proteins including myelin basic protein (MBP) fragment, the inducible form of nitric oxide synthase (iNOS), macrophage markers CD14 and CD64, nitrotyrosine, and cyclooxygenase (COX-2). We also examined MBP, the oligodendrocyte marker cyclic nucleotide phosphodiesterase (CNPase), and glial fibrillary acidic protein. Results: In the affected pathologic nerve, iNOS-positive macrophages/microglia, iNOS-positive astrocytes, COX-2, and nitrotyrosine were observed. iNOS and COX-2 were occasionally observed in the unaffected nerve. Decreased expression of MBP and CNPase was seen in the pathologic optic nerves, along with evidence of gliosis and ongoing myelin degradation indicated by the presence of MBP fragment. Conclusions: The immunohistochemistry of clinically isolated optic neuritis, as judged by this single case, resembles that of cerebral lesions of MS in showing abnormally high levels of iNOS and nitrotyrosine as well as other mediators of immune damage.

Optic neuropathy in a patient with AIDS.

We present a patient with acquired immunodeficiency syndrome (AIDS) with bilateral sequential optic neuropathies attributed to the 14484 mutation of Leber hereditary optic neuropathy (LHON). We discuss the potential interaction of the mitochondrial mutation with antiretroviral therapy and review the literature.

Panhypopituitarism as an initial manifestation of primary central nervous system non-Hodgkin's lymphoma.

OBJECTIVE To report an unusual case of primary central nervous system non-Hodgkins lymphoma in which the initial manifestation was panhypopituitarism. METHODS We present a retrospective case review and discuss similar cases from the literature. RESULTS A 64-year-old woman with nausea, vomiting, diarrhea, and peripheral and periorbital edema was found to have panhypopituitarism. Magnetic resonance imaging showed minimal enlargement of the pituitary, and a transsphenoidal biopsy of the pituitary was nondiagnostic. Months later, abnormalities of extraocular movements developed. Repeated imaging and a second transsphe-noidal biopsy did not reveal the ultimate diagnosis. When further neurologic signs and symptoms subsequently developed, a right temporal open craniotomy was performed. It was not until this procedure, the patients third biopsy, that the cause of her illness was discovered to be diffuse large cell lymphoma. CONCLUSION Although idiopathic panhypopituitarism is a relatively common clinical entity, it remains a diagnosis of exclusion. The development of associated neurologic signs should prompt the clinician to initiate a new search for an underlying cause. This case underscores the protean manifestations of central nervous system lymphoma, both endocrine and neurologic, and the difficulties that may be encountered in attempts to establish a diagnosis.