Perimetric homonymous visual field loss post-stroke.

Post-stroke homonymous visual field (PSHVF) loss has functional and driving implications for patients. Automated, as opposed to confrontational, assessment of PSHVF loss has the potential to provide a more reliable indicator for field loss and thus ability to drive. Sixty-one consecutive stroke admissions were assessed at 9 months post-stroke. Driving status and the patient's awareness of any visual field loss was ascertained. Patients underwent formal perimetric visual field testing using a Humphrey Visual Field Analyser II. A separate, blinded, confrontational assessment of visual fields was made using the National Institutes of Health Stroke Scale (NIHSS) technique. Homonymous field defects were found in 10 (16%) patients, with 50% of these being hemianopia and 50% quadrantanopia. Right-sided field loss was more common (70%). No patients with PSHVF loss were aware of their loss, and only two were detected using NIHSS assessment. One patient was thought to have PSHVF loss on NIHSS assessment but this was not confirmed on perimetry. Of those with significant PSHVF loss at 9 months, 30% were driving. The prevalence of PSHVF loss is relatively high and is underestimated by confrontational testing. Stroke patients are often unaware of their field loss, with up to 5% driving with significantly affected visual fields at 9 months. Perimetric testing may be useful in decision-making regarding driving eligibility post-stroke.

Quinine associated blindness.

BACKGROUND: Quinine is commonly prescribed to the elderly for the treatment of benign nocturnal cramps, yet its use is not without complications. OBJECTIVE: This article presents a case of quinine toxicity producing bilateral blindness, followed by a review of the adverse reactions associated with quinine use and its efficacy in treating benign nocturnal muscular cramps. DISCUSSION: Visual loss has been associated with quinine serum concentrations above 10 microg/mL (therapeutic range 2-5 microg/mL). Other adverse reactions include neurological symptoms, haemolysis, acute renal failure and arrhythmia. There is conflicting evidence for the efficacy of quinine for leg cramps in randomised controlled studies, however, meta-analysis of these studies suggests some benefit. Although severe side effects are rare at therapeutic doses, the possibility of overdose needs to be considered when prescribing and an individual risk benefit analysis needs to be made. Benefits and adverse reactions should be closely monitored and medication ceased if appropriate.