Retromandibular fossa approach to the high cervical internal carotid artery: an anatomic study.

OBJECTIVE: Access to the high cervical internal carotid artery (ICA) is technically challenging for the treatment of lesions in and around this region. The aims of this study were to analyze the efficacy of approaching the high cervical ICA through the retromandibular fossa and to compare preauricular and postauricular incisions. In addition, the relevant neural and vascular structures of this region are demonstrated in cadaveric dissections. METHODS: The retromandibular fossa approach was performed in four arterial and venous latex-injected cadaveric heads and necks (eight sides) via preauricular and postauricular incisions. This approach included three steps: 1) sternocleidomastoid muscle dissection; 2) transparotid dissection; and 3) removal of the styloid apparatus and opening of the retromandibular fossa to expose the cervical ICA with the internal jugular vein along with Cranial Nerves X, XI, and XII. RESULTS: The posterior belly of the digastric muscle and the styloid muscles were the main obstacles to reaching the high cervical ICA. The high cervical ICA was successfully exposed through the retromandibular fossa in all specimens. In all specimens, the cervical ICA exhibited an S-shaped curve in the retromandibular fossa. The external carotid artery was located more superficially than the ICA in all specimens. The average length of the ICA in the retromandibular fossa was 6.8 cm. CONCLUSION: The entire cervical ICA can be exposed via the retromandibular fossa approach without neural and vascular injury by use of meticulous dissection and good anatomic knowledge. Mandibulotomy is not necessary for adequate visualization of the high cervical ICA.