Cerebrospinal fluid leakage complicating orbital exenteration.

In three cases of cerebrospinal fluid leakage complicating orbital exenteration, leakage occurred intraoperatively following relatively low-power (0 to 25 W), high-frequency monopolar cautery to the orbital roof. Six cadaver orbits and 25 dried skulls were examined to investigate possible causes of intraoperative cerebrospinal fluid leakage. In this experimental model, monopolar cautery to the orbital roof did not cause cerebrospinal fluid leakage; however, cautery to preexistent foramina or experimentally created defects in the orbital bones did. In exenteration, monopolar cautery may transmit thermal energy through extant body defects in the orbital roof directly to the dura, resulting in its disruption. These defects may be congenital, tumor related, or iatrogenic. Alternative methods of hemostasis should probably be employed to control bleeding that occurs along the orbital roof during exenteration.