[The qualitative and quantitative diagnostic significance of P-VEP in the evaluation of glaucomatous visual function...

The pattern visual evoked potential (P-VEP) and the central visual field in 63 cases (95 eyes) of primary glaucoma were simultaneously measured with the American Compact Four electrophysiology apparatus and the Chinese TBC-IA central field analyzer. The data showed that the mean latency of P1 in the glaucomatous eyes was significantly lengthened, and this occurred before the visual field and disk abnormalities, indicating that VEP is sensitive in the detection of early glaucoma. Furthermore, the VEP changes were consistent with the central visual field defects qualitatively and quantitatively. Therefore, the latency of P1 can be a useful quantitative index in the evaluation of glaucomatous visual function damage. The difference in diagnostic sensitivity to glaucoma between VEP and visual field changes were discussed. The authors suggest that combination of the two may be a more useful index.