Literature review of cranial nerve injuries during carotid endarterectomy.

OBJECTIVE In the recent prospective randomised trials on carotid endarterectomy (CEA), the incidence of cranial nerve injuries (CNI) are reported to be higher than in previously published studies. The objective of this study is to review the incidence of post CEA cranial nerve injury and to discover whether it has changed in the last 25 years after many innovations in vascular surgery. METHODS Generic terms including carotid endarterectomy, cranial nerve injuries, post CEA complications and cranial nerve deficit after neck surgery were used to search a variety of electronic databases. Based on selection criteria, decisions regarding inclusion and exclusion of primary studies were made. The incidence of CNI before and after 1995 was compared. RESULTS We found 31 eligible studies from the literature. Patients who underwent CEA through any approach were included in the study. All patients had cranial nerves examined both before and after surgery. The total number of patients who had CEA before 1995 was 3521 with 10.6% CNI (352 patients) and after 1995, 7324 patients underwent CEA with 8.3% CNI (614 patients). Cranial nerves XII, X and VII were most commonly involved (rarely IX and XI). Statistical analysis showed that the incidence of CNI has decreased (X(2) = 5.89 + 0.74 = 6.63 => p-value = 0.0100). CONCLUSION CNI is still a significant postoperative complication of carotid endarterectomy. Despite increasing use of CEA, the incidence of CNI has decreased probably because of increased awareness of the possibility of cranial nerve damage.