ISCEV standard for clinical visual evoked potentials (2009 update).

Area of Science:

• Ophthalmology
• Neuroscience
• Clinical Electrophysiology

Background:

• Visual evoked potentials (VEPs) are crucial for assessing visual system function.
• Previous International Society for Clinical Electrophysiology of Vision (ISCEV) standards require updating for improved consistency.
• Clinical electrophysiology laboratories need standardized protocols for reliable VEP testing.

Purpose of the Study:

• To update the ISCEV standard for clinical VEP testing.
• To enhance the precision of VEP test parameters for better inter- and intra-laboratory consistency.
• To provide standardized VEP protocols for assessing prechiasmal visual pathway function.

Main Methods:

• Revision of the 2004 ISCEV standard for clinical VEP testing.
• Definition of precise test parameters for VEP elicitation.
• Specification of core protocols using pattern-reversal, pattern onset/offset, and flash stimuli.
• Recommendation of a single recording channel with a midline occipital electrode for prechiasmal assessment.

Main Results:

• The revised standard introduces more precise test parameters for VEPs.
• Standardized protocols include specific checkerboard sizes for pattern-reversal and onset/offset VEPs (1° and 0.25° checks).
• Flash VEP protocols specify luminance increment stimuli subtending at least 20 degrees.

Conclusions:

• The updated ISCEV standard provides more precise and consistent VEP testing protocols.
• These standardized protocols facilitate reliable assessment of the visual system's functional integrity.
• The defined core protocols are designed for global adoption in clinical electrophysiology labs.