A VEP study of the visual pathway function in compressive lesions of the optic chiasm. Full-field versus half-field stimulation.
Changes of the pattern reversal visual evoked potentials (VEPs) to half- and full-field stimulation in 50 patients with compressive lesions of the optic chiasm are presented. Temporal half-field stimulation yielded abnormal responses in 85% of the eyes, showing non-recordable P100 in 50% of eyes, while in 35% the P100 was significantly attenuated or delayed. With nasal half-field the percentage of all detectable abnormalities was lower (36% of the eyes). Full-field stimulation revealed VEP abnormalities in 74% of eyes and therefore proved less sensitive than the half-field stimulation. This study adds new evidence that half-field stimulation can be an important adjunct for assessing the function of the optic chiasm.
Brecelj
J
J
University Institute of Clinical Neurophysiology, University Medical Centre Ljubljana, Slovenia.
D000293:Adolescent; D000328:Adult; D000368:Aged; D003389:Cranial Nerve Diseases / Q000150:complications / Q000503:physiopathology*; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000150:complications / Q000503:physiopathology*; D009897:Optic Chiasm / Q000503:physiopathology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology