Midline mandibulotomy and interposition grafting for lesions involving the internal carotid artery below the skull base

Background The distal part of the internal carotid artery (ICA) close to the skull base can be reached surgically with different approaches. Exposure using the standard lateral incision is eventually limited by bony structures which preclude the wide-angled operative field necessary for en bloc resection of tumors or primary vascular pathology that abuts the parapharyngeal space. In these unusual cases, use of a combined midline mandibulotomy and neck incision provides necessary operative exposure. Aim We report our experience using combined midline mandibulotomy and neck incision for exposure of high carotid lesions. We also discuss different surgical and endovascular approaches in light of the literature. Patients and Methods Five patients were operated on for high ICA lesions: 2 for malignant head and neck tumors, 1 for an extended paraganglioma, and 2 for large symptomatic ICA aneurysms. All ICAs were reconstructed with an autologous vein interposition graft and the distal anastomoses were performed within the most distal 3 cm of the ICA adjacent to the orifice of bony carotid canal. Results All operations were technically successful with no operative mortality or strokes. One aneurysm patient and the paraganglioma patient had minimal long-term sequelae from this procedure. One patient with an extended lingual epidermoid carcinoma was recurrence free at 3.6 years. One aneurysm patient died due to aspiration pneumonia 30 days postoperatively and another patient had early recurrent tumor growth and died due to that after 15 months. Four patients (80%) suffered a major cranial nerve injury in the operation mainly due to the extensive nature of the disease process. Conclusion Exposure of the distal carotid artery using midline mandibulotomy is rarely required. However, this technique represents an excellent option for cases of malignancies arising from the oral cavity which abut the carotid artery and instances in which primary carotid pathology extends medially alongside the parapharyngeal space. Performance of these cases should be accomplished by a multidisciplinary surgical team comprised of head and neck and vascular specialists. High rates of cranial nerve deficits should be anticipated.