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Purpose: To assess the relationship of aspirin use and ischemic cranial nerve palsies among patients with diabetes mellitus and hypertension., Methods: This retrospective case-control study involved 100 patients with ischemic cranial nerve palsies in association with diabetes, hypertension, or both (palsy cases) and 163 age-matched and sex-matched patients with diabetes, hypertension, or both but without ischemic cranial nerve palsies (nonpalsy control subjects). Comparisons were made with respect to duration of diabetes, dose and duration of aspirin use, dose and duration of tobacco use, and presence of cardiac or cerebrovascular disease., Results: There were 20 oculomotor, 33 trochlear, 37 abducens, and 10 facial nerve palsy cases. The median duration of diabetes was 6 years for cases and 7 years for control subjects. There were 34 cases (34%) who had used aspirin for a mean duration of 5.5 years before the onset of the cranial nerve palsy and 49 control subjects (30.1%) who had used aspirin for a mean duration of 4.3 years. There were no significant differences between cases and control subjects for duration of diabetes (P =.94); aspirin use (P =.51), duration (P =.50), and dosage (P =.89); tobacco use (P =.73) and consumption (P =.45); and proportion of cardiac disease (P =.17). Cerebrovascular disease was significantly less common among palsy cases than nonpalsy control subjects (P<.001). There was no significant difference in the odds of a patient having cranial nerve palsy in the aspirin group compared with the nonaspirin group (odds ratio, 1.12; 95% confidence interval, 0.70-2.04)., Conclusion: Aspirin use was not associated with a reduced rate of ischemic third, fourth, sixth, and seventh nerve palsies among patients with diabetes mellitus and hypertension. Aspirin appears to be ineffective in preventing ischemic third, fourth, sixth, and seventh cranial nerve palsies. Patients with ischemic cranial nerve palsy have a significantly lower rate of strokes and transient ischemic attacks than patients who have diabetes or hypertension but who do not have a history of cranial nerve palsy.

The two examples of phospho and dephospho proteins for which structural data were previously available (glycogen phosphorylase and isocitrate dehydrogenase) demonstrated two different mechanisms for control. In glycogen phosphorylase, activation by phosphorylation results in long-range allosteric changes. In isocitrate dehydrogenase, inhibition by phosphorylation is achieved by an electrostatic blocking mechanism with no conformational changes. During the past year, the structures of the phospho and dephospho forms of two more proteins, the cell cycle protein kinase CDK2 and yeast glycogen phosphorylase, have been determined. The new results highlight the importance of the phosphoamino acids both in the organization of local regions of protein structure through phosphate-arginine interactions and in the promotion of long-range conformational responses.

Purpose: To examine the effect of aspirin use on the visual outcome of nonarteritic anterior ischemic optic neuropathy., Methods: This retrospective case-controlled study included 23 patients who used aspirin regularly before and during the course of nonarteritic anterior ischemic optic neuropathy and 55 control patients with nonarteritic anterior ischemic optic neuropathy. Snellen visual acuity in logMAR and mean deviation on automated perimetry were compiled from the initial and final follow-up examinations., Results: The comparisons of patients who took aspirin with control patients disclosed that neither initial logMAR (P = .36) nor the follow-up logMAR (P = .95) data differed significantly. There was no significant difference between the groups for the initial (P = .60) and the follow-up mean deviation (P = .41)., Conclusions: Aspirin use does not improve the visual outcome of patients with nonarteritic anterior ischemic optic neuropathy. Additional studies are needed to further elucidate this issue.

Purpose: We conducted a pilot clinical trial to determine the efficacy of levodopa in promoting visual recovery in eyes with nonarteritic anterior ischemic optic neuropathy of greater than six months' duration., Methods: This prospective, randomized, double-masked, placebo-controlled clinical trial involved 20 subjects with nonarteritic anterior ischemic optic neuropathy of 30 months' mean duration. Subjects were randomly assigned to receive either low-dose levodopa and carbidopa or a placebo for three weeks. At 12 weeks after the baseline visit, the levodopa group then was provided a higher, conventional dose of levodopa and carbidopa for three more weeks. Change in visual function was monitored at four, 12, 16, and 24 weeks after the baseline visit., Results: At 12 weeks after the baseline visit, the levodopa group experienced a significant (P = .016) mean difference in improvement of visual acuity of 5.9 letters from the placebo group. At 24 weeks after the baseline visit, a significant treatment effect (P = .036) for visual acuity was still evident; the levodopa group had a mean gain in improvement of 7.5 letters difference from baseline from the placebo group. Three subjects in the levodopa group experienced a doubling of the visual angle as denoted by a gain of at least 15 letters. Significant improvement was not observed for color vision (P = .82) or mean deviation of visual field loss (P = .82)., Conclusion: The study found significant improvement of visual acuity among subjects receiving levodopa and carbidopa despite long-standing visual loss from nonarteritic anterior ischemic neuropathy. Confirmation of our results is awaited from larger population studies and with a longer follow-up time interval regarding the efficacy of levodopa in reversing visual loss in this disease.

The histopathologic findings in a case of ocular invasion in rhinocerebral mucormycosis are described. The findings of hyphae in the inner sclera and marked involvement of the posterior ciliary arteries suggested an arterial route of ocular invasion by fungus. Only five other cases of rhinocerebral mucormycosis with ocular fungal invasion have been reported to our knowledge. All six patients died from the infection. As a group, these cases suggest that the presence of ocular infiltration by fungus may indicate poor prognosis in rhinocerebral mucormycosis.

1. A tetradecapeptide containing the phosphorylation site was obtained from 32P-labelled pig heart phosphorylase a isoenzyme by alpha-chymotryptic digestion. 2. The peptide was purified by Mono S cation-exchange chromatography and reversed-phase HPLC. 3. The phosphorylated residue was identified as Ser and the sequence was determined: T D G E R R K Q I S V R G L. 4. The sequence was compared to the known sequences of muscle and liver type isophosphorylases and the structural consequences of the amino acid residue exchanges were predicted.

Craniopharyngiomas are common tumors located in the suprasellar region. Contrast enhancement, cyst formation, and calcification are the three characteristic features of craniopharyngiomas on computed tomographic scan. More than 90% of suprasellar craniopharyngiomas exhibit at least two of these three features, thus providing easy radiologic detection. We treated a 41-year-old man in whom a large suprasellar craniopharyngioma producing severe visual loss was not detected by computed tomography but was easily identified with magnetic resonance imaging. Thus, despite high-resolution computed tomographic scan, large suprasellar craniopharyngiomas can be missed. Magnetic resonance imaging may be superior to computed tomography in detecting these tumors.

Two patients (two men, 56 and 59 years old) had sphenoid sinus mucocele originating in the anterior clinoid process. In one case the mucocele initially mimicked diabetic ophthalmoplegia with pupil-sparing palsy of the oculomotor (third) nerve. After resolution of the palsy, severe visual loss developed with minimal recovery of vision after surgery. The second patient had recurrent episodes of retrobulbar optic neuropathy with optic atrophy and decreased vision. Visual loss from sphenoid sinus mucoceles is usually associated with a poor prognosis if surgical treatment is delayed more than seven to ten days.