The changing shape of the ISCEV standard pattern onset VEP

Area of Science:

• Neuroscience
• Ophthalmology
• Visual Electrophysiology

Background:

• The International Society for Clinical Electrophysiology of Vision (ISCEV) provides a standard for visual evoked potential (VEP) recordings.
• The pattern onset VEP waveform, characterized by C1-C2-C3 peaks and troughs, is not consistently observed in all individuals.
• Understanding age-related changes in VEPs is crucial for accurate interpretation and reliable recording.

Purpose of the Study:

• To investigate the developmental changes in pattern onset VEPs with age.
• To determine the age at which the ISCEV standard onset VEP waveform can be reliably recorded.

Main Methods:

• Pattern onset VEPs were recorded from 24 adults (20-63 years) using ISCEV standard methods.
• Stimuli included checks of 60 and 15 arc minutes in a 15° visual field.
• VEP waveforms were compared to the ISCEV standard and pediatric VEPs.

Main Results:

• VEP waveform shape evolved gradually with age.
• The ISCEV standard C1-C2-C3 morphology was consistently observed in adults over 40 years with 60' checks.
• Smaller 15' checks yielded earlier peak latencies and a more pronounced C2 trough.

Conclusions:

• The ISCEV standard onset VEP waveform accurately represents recordings from adults over 40 years using 60' checks.
• The 15' check stimulus elicits a distinct VEP with earlier latencies and a more prominent C2 component.