Delayed cranial neuropathy after neurosurgery caused by herpes simplex virus reactivation: report of three cases.

BACKGROUND: Delayed cranial neuropathy is an uncommon complication of neurosurgical interventions of which the exact etiology is uncertain. Several authors have hypothesized that reactivation of herpesviruses may play a role. CASE DESCRIPTIONS: The first patient underwent microvascular decompression of the left facial nerve because of hemifacial spasm. Nine days postoperatively, he developed severe facial weakness on the ipsilateral side. The polymerase chain reaction for herpes simplex virus (HSV) was positive in the cerebrospinal fluid (CSF). Treatment with intravenous acyclovir was initiated, after which a rapid and marked improvement was observed. The second patient developed left-sided facial numbness 20 days after microvascular decompression of the left facial nerve. The polymerase chain reaction for HSV was positive in the CSF. Treatment with intravenous acyclovir resulted in full recovery. The third patient underwent a suboccipital craniectomy with excision of a meningioma located at the left petrosal apex. Three months postoperatively, she developed multiple cranial neuropathies (involving cranial nerves V, VI, VIII, and XII). This was accompanied by serologic evidence of HSV reactivation and a positive polymerase chain reaction for HSV in the CSF. The patient was successfully treated with intravenous acyclovir.
CONCLUSIONS: The 3 reported cases provide evidence that delayed postoperative cranial neuropathy can be caused by HSV reactivation and can involve multiple cranial nerves. An increased awareness of this treatable postoperative complication is warranted.