title: The application of flash visual evoked potentials during operations on the anterior visual pathways.
abstract: Flash visual evoked potentials (F-VEP's) have been recorded in fifteen patients (thirty eyes) with anterior visual pathway compression lesions before, during and after the operation in relation to clinical visual testing. A grading system for the wide variety of abnormal F-VEP's has been established, based on changes in forty patients (eighty eyes). No significant correlation between change in F-VEP and visual acuity or visual field has been demonstrated. Intraoperative F-VEP's have been found to be sensitive to halothane and to surgical manipulation of the optic nerve and/or chiasm during dissection of the tumour. The technique is considered a useful means of identifying the optic pathway during operation and may assist in prevention of optic damage if the transphenoidal approach is used.
authors.forename: I
authors.initials: I
authors.lastname: Costa e Silva
authors.forename: A D
authors.initials: AD
authors.lastname: Wang
authors.forename: L
authors.initials: L
authors.lastname: Symon
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000503:physiopathology / Q000601:surgery*; D003397:Craniopharyngioma / Q000503:physiopathology / Q000601:surgery*; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008579:Meningioma / Q000503:physiopathology / Q000601:surgery*; D008875:Middle Aged; D010911:Pituitary Neoplasms / Q000503:physiopathology / Q000601:surgery*; D011930:Reaction Time / Q000502:physiology; D014792:Visual Acuity; D014794:Visual Fields; D014795:Visual Pathways / Q000503:physiopathology*