Visual evoked responses and immunoglobulin abnormalities in the diagnosis of multiple sclerosis.

Visually evoked responses (VERs), CSF IgG/albumin ratio and CSF oligoclonal IgG were examined in 136 patients with multiple sclerosis (MS) admitted to hospital for investigation, and compared to the CSF findings in 87 patients with other neurological diseases (OND). 33% of patients with OND had abnormal CSF IgG/albumin ratios but only 9% had CSF oligoclonal IgG banding. In clinically definite MS, VERs were abnormal in 87% and CSF oligoclonal banding was found in 80% of patients, but CSF oligoclonal banding was found significantly more frequently than abnormal VERs in patients with suspected MS. We were unable to show any relationship between benign MS and the absence or presence of CSF oligoclonal IgG. The significance of CSF oligoclonal IgG in the less clinically definite forms of MS will only emerge with prolonged follow-up.