RESUMO
The detection of hidden visual loss is important in establishing the diagnosis of multiple sclerosis, especially in patients who have neurologic symptoms of the disease. Both visual evoked potentials and contrast sensitivity have been used for this purpose. We compared the sensitivities of pattern-reversal visual evoked potentials and contrast sensitivity, measured with the Vistech VCTS 6500 chart, in detecting hidden visual loss in 18 patients with multiple sclerosis whose visual acuity was correctable to 20/20 (6/6) or better in the examined eye. Thirteen patients had delayed visual evoked potential latencies. An additional four patients had reduced P100 amplitudes without prolonged latencies. Nine patients had abnormal contrast sensitivity. The visual evoked potential was more sensitive than contrast sensitivity at detecting hidden visual loss in patients with multiple sclerosis (p less than 0.01).
Assuntos
Sensibilidades de Contraste , Potenciais Evocados Visuais , Esclerose Múltipla/fisiopatologia , Transtornos da Visão/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos , Sensibilidade e Especificidade , Acuidade VisualRESUMO
The sensitivity of the VISTECH chart in the detection of hidden visual loss is debated. We tried to evaluate the diagnostic value of the test by using different illumination levels. Twelve MS-patients with normal acuity but a pathological VEP were examined at 9 different illuminations. We did not identify more abnormalities among patients, using VISTECH test at other illumination levels than the one recommended by the manufacturer.
