Visual evoked potentials in tumors from orbita to occipital lobe in childhood.

68 infants and children with proven tumours along the visual pathway visually evoked potentials with pattern reversal and flash were investigated. Subdivided in 5 locational groups (orbital, optic nerve, chiasmatic, retrochiasmatic and occipital lobe) best results were obtained by stimulation with pattern reversal using variable checksizes (91.2%) versus 61.8% by using flash evoked responses. Furthermore, using patterned stimuli not only latency shifts are best detected but also hints for visual function correlating to visual acuity could be given also in nonverbal or disabled children. For long term follow-up studies in known space-occupying lesions along the visual pathway, the use of pattern VEP is extraordinary because of its high sensitivity and complete harmlessness. Pattern VEP are even more sensitive than visual acuity testing in cooperative patients. The close interdisciplinary follow-up controls in these children between pediatric neurophysiologists and neurosurgeons are, therefore, strongly recommended.