Monitoring visual evoked response during craniofacial surgery.

A case is presented in which intraoperative visual evoked response (VER) monitoring was employed during correction of orbital hypertelorism. This procedure is noninvasive and does not interfere with the execution of the operation. The operative time is prolonged only a few minutes to record the VER. This technique is a simple and safe method for detecting intraoperative damage to the optic nerve and chiasm, and may prove useful in avoiding damage to these critical structures during craniofacial surgical procedures.