Retinal Arterio-Arterial Collaterals in Susac Syndrome.

BACKGROUND: The ophthalmic findings of Susac syndrome (SS) consist of visual field defects related to branch retinal artery occlusion (BRAO), and fluorescein angiography (FA) reveals a unique staining pattern. To date, retinal arterial collateral development has been described only in a single patient. Given that the immunopathological process in SS induces retinal ischemia, it is conceivable that abnormal blood vessel development may occur in affected individuals. METHODS: This is a retrospective observational study. The medical records including fundus photography and FA of all patients with SS were reviewed, and those with any type of retinal arterial collateral were identified. RESULTS: A total of 11 patients were identified with retinal collaterals. Five were men. Age ranged from 20 to 50 years. Ten patients had arterio-arterial (A-A) collaterals and 1 had arterio-venous (A-V) collaterals, and all had collaterals remote from the optic disc. No collaterals were present at onset of illness and the first developed at 9 months. CONCLUSIONS: The literature reveals scant evidence for the association between BRAO and retinal arterial collaterals. Our findings indicate that retinal arterial collaterals in SS are usually A-A and not A-V and may be more common in this disorder than previously believed. Collaterals do not develop early in the disease, and there may be a predilection toward development in men. The chronic inflammatory state of SS may be the stimulus for the development of these arterial collaterals.

Is Multiple Sclerosis Associated With a Lower Intraocular Pressure?

OBJECTIVE: To determine if multiple sclerosis (MS) is associated with lower intraocular pressure (IOP) compared with individuals without MS. METHODS: Thirty patients with clinically definite MS were identified and a retrospective chart review was conducted. Each patient with MS underwent IOP recording by a single investigator using kinetic applanation tonometry. Measurement of central corneal thickness (CCT) also was obtained. Similarly, 30 study controls were identified and kinetic applanation tonometry and CCT were recorded. Univariate analysis of covariance was conducted to determine a statistically significant difference between IOP between MS and control groups, controlling for age. RESULTS: Analyses were adjusted for age and 2 subjects were excluded because of steroid use. The average IOP in MS group was 12.3 mm Hg (right eye = 12.3 mm Hg, left eye = 12.2 mm Hg) and in the control group was 17 mm Hg (right eye = 16.9 mm Hg, left eye = 17 mm Hg). There was a significant effect of presence of MS on IOP accounting for 53% variability in mean IOP (F(1,55) = 60.7; P < 0.001) when compared with the control group. CONCLUSIONS: This study demonstrated that IOP was significantly lower in patients with MS compared with controls. A more in-depth prospective study design is required, along with further investigation of possible etiologies. Identifying the mechanism of decreased IOP in patients with MS might allow development of new-targeted therapies for the treatment of glaucoma.

Novel treatment for radiation optic neuropathy with intravenous bevacizumab.

Radiation optic neuropathy is a devastating form of vision loss that can occur months to years after radiation therapy for tumors and other lesions located in close proximity to the visual pathways. We present the case of a 24-year-old woman who underwent external beam radiation for treatment of a tectal pilocytic astrocytoma, and 5 years later she developed bilateral radiation optic neuropathy and radiation necrosis of the right temporal lobe. We opted to treat her with intravenous bevacizumab with 3 doses every 3 weeks, as well as dexamethasone and pentoxifylline. After the first infusion of bevacizumab, the patient noted improvement in vision and color vision, and a follow-up magnetic resonance imaging study showed that the previous enhancement of the optic nerves and chiasm was diminishing. Her vision improved dramatically and has remained stable over a 3-year period.

Toluene optic neurotoxicity: magnetic resonance imaging and pathologic features.

Toluene, a colorless liquid found in glues, paints, and industrial products, is lipid soluble and rapidly absorbed by the lipid-rich central nervous system. Prolonged exposure through occupation or purposeful inhalation may lead to neurologic abnormalities. Two men presented with multifocal central nervous system defects and bilateral optic neuropathy of unclear etiology. After numerous diagnostic tests, including brain magnetic resonance imaging, lumbar puncture, hematologic studies, and in one patient a brain biopsy, chronic inhalation of toluene was found to be the cause. Timely diagnosis is important because patients may experience improvement in neurologic and ocular manifestations with cessation of exposure, whereas continued inhalant abuse or exposure can result in permanent loss of neurologic function.

Treatment of chronic facial pain.

Facial pain occurs because of damage to the fifth cranial nerve anywhere along its course from its terminal subcutaneous craniofacial branches to the brainstem. Although topical agents may be effective in relieving pain caused by subcutaneous branch damage, systemic oral agents are usually needed to alter or correct deeper trigeminal nociceptive pain caused by damage to the trigeminal nerve further along its course. Antidepressive agents with anti-nociceptive properties, anticonvulsants, and anti-inflammatory agents are most commonly used. Newer agents are beginning to replace the commonly used first-line medications. Combination therapy is popular because it maximizes the effect of each drug while reducing the side effects seen in higher-dose monotherapy. Treatment of secondary clinical depression is very important in the management of patients with facial pain, explaining the beneficial dual role of antidepressants in this condition. Alternative and holistic approaches are also popular, but most are not confirmed by controlled studies at the present time.

Recurrent optic neuritis as the presenting manifestation of primary hypereosinophilic syndrome: a report of two cases.

Two patients sustained multiple attacks of optic neuritis with persistent visual loss. An elevated eosinophil count was initially considered an incidental finding. Years later, the diagnosis of primary hypereosinophilic syndrome (HES) was confirmed by skin and bone marrow in one patient and by lung biopsy in the other. Treatment with hydroxyurea in one patient and with continuous low-dose prednisone in the other stopped the optic neuritis attacks, resolved systemic manifestations, and stabilized neurologic manifestations. These cases emphasize that primary HES may be a cause of recurrent optic neuritis, and that delay in diagnosis and treatment of primary HES can lead to visual morbidity.