Artery of Percheron and Endoscopic Endonasal Surgery: Case Report and Review of the Literature.

Artery of Percheron (AOP) is a rare anatomical variant in which a single perforating artery arising from the P1 segment of the posterior cerebral artery supplies paramedian thalami and rostral midbrain. The occlusion of AOP produces bilateral thalamic ischemia and may be a rare complication in relation to an extended endoscopic endonasal approach. We report the case of a patient who developed AOP damage during endoscopic endonasal surgery (EES); to our knowledge, this complication has been previously reported only in one case, in relation to a second surgery. We also review the anatomical variants in thalamic vascularization and the factors that may be involved in this complication. A 52-year-old female underwent an extended endoscopic endonasal approach with intraoperative neurophysiological monitoring. In the postoperative period, she presented with a decreased level of consciousness and bilateral mydriasis. Magnetic resonance imaging showed rostral midbrain and paramedian thalami ischemia congruent with AOP infarction. AOP infarction may be associated with extended EES when treating lesions with retrosellar extension. Every effort should be made to preserve the small perforating arteries. Intraoperative neurophysiological monitoring of the motor and sensory pathways may not detect damage to the AOP.

Intraoperative Use and Benefits of Tractography in Awake Surgery Patients.

OBJECTIVE: The present study analyzed the benefits of the use of tractography in the preoperative and intraoperative scenarios. METHODS: We present a prospective cohort study with 2 groups of patients who had undergone awake surgery for brain tumor resection. A control group for which no intraoperative navigated diffusion tensor imaging (DTI) was used (non-DTI group) and the case group (DTI group). The operative time, complete tumor resection, and neurological postoperative deficits were measured as primary outcomes. A secondary analysis was performed to determine the power of preoperative DTI to predict for complete tumor resection. RESULTS: A total of 37 patients were included, 18 in the non-DTI group and 19 in the DTI group. No differences were found between the 2 groups for sex, mean age, tumor histological findings, and preoperative mean tumor volume. The awake surgical time in the non-DTI group was 119.8 ± 31.1 minutes and 93.6 ± 12.2 minutes in the DTI group (P = 0.007). A trend was found toward complete tumor resection in the DTI group (P = 0.09). The sensitivity and specificity for predicting complete tumor resection were 88% and 62.5% for the non-DTI group and 100% and 80% for the DTI group, respectively. The area under the receiver operating characteristic curve was 0.720 in the non-DTI group and 0.966 in the DTI group (P = 0.041). CONCLUSIONS: Intraoperative navigated tractography shortened the time of awake neuro-oncological surgery and might provide help in performing complete tumor resection. Also, tractography used in the preoperative planning could be a useful tool for better prediction of complete tumor resection.