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.

Evaluation of on-road driving in people with hemianopia and quadrantanopia.

OBJECTIVE: To examine whether some drivers with hemianopia or quadrantanopia display safe driving skills on the road compared with drivers with normal visual fields. METHOD: An occupational therapist evaluated 22 people with hemianopia, 8 with quadrantanopia, and 30 with normal vision for driving skills during naturalistic driving using six rating scales. RESULTS: Of drivers with normal vision, > 90% drove flawlessly or had minor errors. Although drivers with hemianopia were more likely to receive poorer ratings for all skills, 59.1%-81.8% performed with no or minor errors. A skill commonly problematic for them was lane keeping (40.9%). Of 8 drivers with quadrantanopia, 7 (87.5%) exhibited no or minor errors. CONCLUSION: This study of people with hemianopia or quadrantanopia with no lateral spatial neglect highlights the need to provide individual opportunities for on-road driving evaluation under natural traffic conditions if a person is motivated to return to driving after brain injury.

On-road driving performance by persons with hemianopia and quadrantanopia.

PURPOSE: This study was designed to examine the on-road driving performance of drivers with hemianopia and quadrantanopia compared with age-matched controls. METHODS: Participants included persons with hemianopia or quadrantanopia and those with normal visual fields. Visual and cognitive function tests were administered, including confirmation of hemianopia and quadrantanopia through visual field testing. Driving performance was assessed using a dual-brake vehicle and monitored by a certified driving rehabilitation specialist. The route was 14.1 miles of city and interstate driving. Two "back-seat" evaluators masked to drivers' clinical characteristics independently assessed driving performance using a standard scoring system. RESULTS: Participants were 22 persons with hemianopia and 8 with quadrantanopia (mean age, 53+/-20 years) and 30 participants with normal fields (mean age, 52+/-19 years). Inter-rater agreement for back-seat evaluators was 96%. All drivers with normal fields were rated as safe to drive, while 73% (16/22) of hemianopic and 88% (7/8) of quadrantanopic drivers received safe ratings. Drivers with hemianopia or quadrantanopia who displayed on-road performance problems tended to have difficulty with lane position, steering steadiness, and gap judgment compared to controls. Clinical characteristics associated with unsafe driving were slowed visual processing speed, reduced contrast sensitivity and visual field sensitivity. CONCLUSIONS: Some drivers with hemianopia or quadrantanopia are fit to drive compared with age-matched control drivers. Results call into question the fairness of governmental policies that categorically deny licensure to persons with hemianopia or quadrantanopia without the opportunity for on-road evaluation.

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.

Unusual presentation of gastric adenocarcinoma metastatic to the orbit.

A 69-year-old woman with no history of malignant disease presented with complaints of ptosis, diplopia, and left upper eyelid fullness. Computed tomography showed soft tissue infiltration of the left superior orbit. Biopsy was performed through an anterior orbitotomy. Histopathology revealed a mucinous adenocarcinoma. Subsequent systemic evaluation included esophagogastroduodenoscopy, which revealed a primary gastric malignancy.

Resistance training exercises acutely reduce intraocular pressure in physically active men and women.

Our purpose was to examine the effect of the chest press and leg press exercises on intraocular pressure (IOP) in physically active, college-aged students. Fifteen healthy males and 15 females performed 3 sets of 10 repetitions of the chest press or leg press with 70% 1 repetition maximum (1RM). IOP was measured using applanation tonometry with a Tono-PenXL prior to exercise, following each set and 5 minutes after the third set. Data were analyzed with a repeated-measures two-way analysis of variance and paired t-tests when necessary. A p < 0.05 was accepted as statistically significant. For the chest press, IOP was reduced 8.0% after the first set, up to 14.5% after the second and third sets, and remained depressed 5 minutes post exercise. For the leg press, IOP was reduced 6.9% after the second set and 13.2% after the third set. IOP began to return to the pre-exercise value during 5 minutes post exercise. Males and females had similar IOP responses to the chest press and leg press exercise. Dynamic resistance exercises induce modest postexercise decreases in IOP.