Ronald A. Braswell

Hemianopic and Quadrantanopic Field Loss, Eye and Head Movements, and Driving

PURPOSE To compare eye and head movements, lane keeping, and vehicle control of drivers with hemianopic and quadrantanopic field defects with controls, and to identify differences in these parameters between hemianopic and quadrantanopic drivers rated safe to drive by a clinical driving rehabilitation specialist compared with those rated as unsafe. METHODS Eye and head movements and lane keeping were rated in 22 persons with homonymous hemianopic defects and 8 with quadrantanopic defects (mean age, 53 years) who were ≥6 months post-injury and 30 persons with normal fields (mean age, 53 years). All were licensed to drive and were current drivers or aimed to resume driving. Participants drove a 6.3-mile route along non-interstate city roads under in-traffic conditions. Vehicle control was assessed objectively by vehicle instrumentation for speed, braking, acceleration, and cornering. RESULTS As a group, drivers with hemianopic or quadrantanopic defects drove slower, exhibited less excessive cornering or acceleration, and executed more shoulder movements than the controls. Those drivers with hemianopic or quadrantanopic defects rated as safe also made more head movements into their blind field, received superior ratings regarding eye movement extent and lane position stability, and exhibited less sudden braking and drove faster than those rated unsafe. CONCLUSIONS Persons with hemianopic and quadrantanopic defects rated as safe to drive compensated by making more head movements into their blind field, combined with more stable lane keeping and less sudden braking. Future research should evaluate whether these characteristics could be trained in rehabilitation programs aimed at improving driving safety in this population.

Resolution of Chiari I Malformation Following Acetazolamide Therapy

A 25-year-old obese woman developed headaches and visual blurring. Examination showed papilledema and cranial MRI showed a large Chiari I malformation. Acetazolamide was initiated and a repeat cranial MRI surprisingly showed resolution of the Chiari I malformation. Chiari I malformation associated with papilledema has never been shown to resolve with acetazolamide therapy.

Neuro-ophthalmologic manifestations of sarcoidosis.

Sarcoidosis is a multisystem disorder characterized by granulomatous inflammation. There have been numerous reports describing its epidemiology and immunopathology, yet the etiology of sarcoidosis remains unknown. By definition, neuro-ophthalmologic manifestations of this disorder fall under the rubric of neurosarcoidosis, indicative of involvement of the nervous system. In general, with neurologic findings present, other organ systems are involved. For this reason, systemic evaluation of the patient is warranted. But exceptions do occur, where sarcoidosis involves only the central nervous system, and particularly the visual system. This article will review sarcoidosis in general, delineate ocular involvement, and describe and illustrate the neuro-ophthalmologic signs and symptoms of this disorder. Because of its protean and variable clinical presentation, sarcoidosis presents a formidable challenge for the ophthalmologist both diagnostically and therapeutically.