Sensitivity and Specificity of Short-Duration Transient Visual Evoked Potentials (SD-tVEP) in Discriminating Normal From Glaucomatous Eyes

We tested 30 normal eyes of 30 healthy controls and 45 eyes of 35 glaucoma patients. Normal eyes had 20/30 or better visual acuity and normal 24-2 SITA Standard visual fields (VF). Glaucoma was staged as mild, moderate and advanced (15 eyes each). Synchronized single-channel SD-tVEPs were recorded using the Diopsys® NOVA-LX (Fixed Protocol) System (Diopsys, Inc. Pine Brook, NJ). Each eye was stimulated with a 15% and 85% Michelson contrast checkerboard pattern. Test duration was 38 seconds/eye. Each resulting test resulted in a low and high contrast VEP response. Each response was evaluated for overall waveform quality, N75 and P100 latency, and the amplitude difference of the P100 and N75. Asymmetries between OS and OD latencies and amplitudes were evaluated. The sensitivity and specificity was calculated for the entire population and for each category.