The microsurgical treatment of cranio-orbital tumors assisted by intraoperative electrophysiologic monitoring and neuronavigation.

Objective: Total resection of cranio-orbital tumors without any major complications is still a challenge for neurosurgeons. Intraoperative electrophysiologic monitoring and neuronavigational system have been widely used in microneurosurgery, but their effects during microsurgical treatment of cranio-orbital tumors warrant further investigation.

Methods: Thirty-eight patients with cranio-orbital tumors admitted to our hospital underwent microsurgery assisted by intraoperative electrophysiologic monitoring. We also simultaneously performed intraoperative neuronavigation in 20 patients. A retrospective review of clinical notes, operation records and prognoses of all patients was performed.

Results: Gross total resection was achieved in 29 patients (76%), near total resection in 5 (13%), subtotal resection in 3 (8%) and partial resection in 1 (3%). With the helps of electromyogram (EMG) monitoring of levator palpebrae superioris (LPS) muscle and navigation system, no surgical damages to the oculomotor nerve and other important structures occurred. A follow-up study showed that 31 patients (82%) resumed normal lives (Glasgow Outcome Scale (GOS) score 5), 5 patients (13%) had independent lives (GOS score 4), and 2 patients (5%) were unable to live independently (GOS score 3).

Conclusion: Microsurgical treatment assisted by intraoperative electrophysiologic monitoring and neuronavigation might be a useful method for resection of cranio-orbital tumors, especially better for protection of the important cranial nerve and structure in the kull base.