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The latency for saccadic eye movements to a visual stimulus was studied in 59 adults whose ages ranged from 20.7 to 79.5 years. All were free of neurologic disease and drug use. Horizontal eye movements were recorded by electrooculography and the latency from the onset of a peripheral visual stimulus to the onset of a saccadic refixation eye movement was determined. A linear regression analysis revealed a correlation between increasing age and increasing latency for saccadic refixation eye movements. The direct relationship between increasing age and increasing latency for saccadic eye movements is a factor that should be taken into account in eye-movement studies as well as other methodologies such as tachistoscopic studies in which saccadic eye movements play a role in study design.

Lhermitte-Duclos disease is a benign, presumably hamartomatous lesion of the cerebellum which presents clinically as a mass lesion. Pathologically, it consists of thickening of both the molecular and granular cell layers of the cerebral cortex which enlarges the folia but allows for preservation of the gyral pattern of the cerebellar cortex. Preoperative diagnosis with computerized tomography and other studies has not been possible, and even at surgery the diagnosis may be missed because of the preservation of the gyral pattern. The sensitivity of magnetic resonance imaging allows recognition of the cortical nature of the mass lesion, and especially the gyral pattern within the mass lesion, providing a diagnostic image which is unlikely to be confused with any other pathological process in the cerebellum. Preoperative diagnosis of Lhermitte-Duclos disease allows surgeons to plan an appropriate decompressive procedure.

Background and Purpose: The relation between anterior ischemic optic neuropathy and carotid artery atherosclerotic disease is unclear. We studied patients with anterior ischemic optic neuropathy to determine if they had an increased occurrence of carotid artery stenosis.Methods: Fifteen consecutive patients with anterior ischemic optic neuropathy were evaluated prospectively for cervical carotid artery stenosis and compared with 30 age-and sex-matched asymptomatic patients and also with 11 age-and sex-matched patients experiencing transient monocular blindness.Results: There was no difference in the mean stenosis of the internal carotid artery between patients with anterior ischemic optic neuropathy (mean carotid stenosis, 19%) and asymptomatic patients (mean carotid stenosis, 9%;/»>0.05), whereas patients with transient monocular blindness had significantly more stenosis (mean, 77%) in the cervical carotid arteries than both control subjects (p<0.0001) and patients with anterior ischemic optic neuropathy (p<0.0001). There was also no difference in the percentage of patients with stenosis >30% in anterior ischemic optic neuropathy (two of 15) and asymptomatic patients (five of 30), whereas 10 of 11 patients with transient monocular blindness had stenoses >30%, significantly more than patients with anterior ischemic optic neuropathy (p<0.0001) and asymptomatic patients (p<0.0001).Conclusions: Anterior ischemic optic neuropathy is not a marker for atherosclerotic carotid artery stenosis. The pathogenesis of nonarteritic anterior ischemic optic neuropathy does not involve carotid artery stenosis in most patients.

Venous stasis retinopathy and ischemic oculopathy are ocular manifestations of ischemia in the distribution of the carotid artery. While not as common as transient monocular blindness or retinal arterial emboli, they are readily recognizable and indicate the presence of severe, often bilateral, carotid occlusive disease. Patterns of occlusion vary but usually include complete occlusion of at least one common or internal carotid artery, often accompanied by occlusion or narrowing in the opposite carotid system. The ocular findings in venous stasis retinopathy and ischemic oculopathy indicate ongoing ocular ischemia and may progress to intractable neovascular glaucoma. Therapy, individualized for the specific pattern of occlusive changes, may be directed toward prevention of stroke or may be indicated primarily for the reversal of ocular ischemia and prevention of blindness secondary to neovascular glaucoma.