Visual pattern evoked responses and blink reflexes in assessment of MS diagnosis

Summary VEPs were measured after pattern reversal in 135 MS patients and 30 control subjects. Neurological findings were documented in a standard manner. An extensive ophthalmological examination of all subjects was part of the study. The latency of P₂ was abnormally delayed in 82% of the definite, in 60% of the probable and in 65% of the possible MS groups respectively. The VEP was more often delayed in relation to ophthalmological disturbances. Changes in the MS classification had to be made in more than 10% of the patients, due to delay of VEP latency. These were patients with a spinal form of MS, which is known to create diagnostic problems.Optically and electrically evoked blink reflexes were recorded in 107 MS patients. All patients with mesencephalic lesions had delayed responses of the optically evoked reflex. 74% of the patients with caudal brainstem lesions had delayed latencies of the components of the electrically evoked blink reflex. The blink reflex was delayed in 18 additional patients without brainstem signs. The possibility of delineating clinically silent brainstem lesions by investigating blink reflexes is discussed.Supported by the Deutsche Forschungsgemeinschaft (Dr. Fischer Bosch-Stiftung).