Enes Yigit1,2, Engin Dursun3, Elif Omeroglu4, Ahmet Volkan Sunter5, Deniz Tuna Edizer6, Suat Terzi3, Zerrin Ozergin Coskun3, Munir Demirci3. 1. Department of Otorhinolaryngology, Recep Tayyip Erdogan University, Faculty of Medicine, Rize, Turkey. enesssyigit@hotmail.com. 2. Department of E.N.T., Luleburgaz State Hospital, Istiklal Mahallesi, Istanbul Caddesi No:174, Luleburgaz, Kirklareli, Turkey. enesssyigit@hotmail.com. 3. Department of Otorhinolaryngology, Recep Tayyip Erdogan University, Faculty of Medicine, Rize, Turkey. 4. Mortuary Department, The Ministry of Justice's Council of Forensic Medicine, Istanbul, Turkey. 5. Department of Otolaryngology Head and Neck Surgery, Istanbul Training and Research Hospital, Istanbul, Turkey. 6. Department of Otolaryngology Head and Neck Surgery, Izmir Bozyaka Training and Research Hospital, Izmir, Turkey.
Abstract
PURPOSE: To evaluate the course of lower cranial nerves (CNs) within the neck in relation to surrounding structures and anatomic landmarks via a cadaveric dissection study. METHODS: A total of 70 neck dissections (31 bilateral, 8 unilateral) were performed on 39 adult fresh cadavers [mean (SD) age: 38.5 (11.2) years, 29 male, 10 female] to identify the course of lower CNs [spinal accessory nerve (SAN), vagus nerve and hypoglossal nerve] within the neck in relation to surrounding structures [internal jugular vein (IJV), common carotid artery (CCA)] and distance to anatomical landmarks (cricoid cartilage, hyoid bone, digastric muscle). RESULTS: SAN travelled most commonly anterior to IJV (51.4%) at the level of jugular foramen, while travelling lateral to IJV at the post belly of digastric (55.7%) and inferior to digastric muscle (90%) in most neck dissections. Vagus nerve travelled lateral to CCA in majority (94.3%) of dissections, while medial (2.9%), posterolateral (1.4%) and posterior (1.4%) positions were also noted. Average distance of hypoglossal nerve was 27.7 (9.7) mm to carotid bifurcation, 9.3 (3.9) mm to hyoid bone, and 54.7 (18.0) mm to the inferior border of cricoid cartilage. CONCLUSION: In conclusion, our findings indicate that anatomic variations are not rare in the course of lower CNs within the neck in relation to adjacent structures, and awareness of these variations together with knowledge of distance to certain anatomic landmarks may help the surgeon to identify lower CNs during neck surgery and prevent potential nerve injuries.
PURPOSE: To evaluate the course of lower cranial nerves (CNs) within the neck in relation to surrounding structures and anatomic landmarks via a cadaveric dissection study. METHODS: A total of 70 neck dissections (31 bilateral, 8 unilateral) were performed on 39 adult fresh cadavers [mean (SD) age: 38.5 (11.2) years, 29 male, 10 female] to identify the course of lower CNs [spinal accessory nerve (SAN), vagus nerve and hypoglossal nerve] within the neck in relation to surrounding structures [internal jugular vein (IJV), common carotid artery (CCA)] and distance to anatomical landmarks (cricoid cartilage, hyoid bone, digastric muscle). RESULTS: SAN travelled most commonly anterior to IJV (51.4%) at the level of jugular foramen, while travelling lateral to IJV at the post belly of digastric (55.7%) and inferior to digastric muscle (90%) in most neck dissections. Vagus nerve travelled lateral to CCA in majority (94.3%) of dissections, while medial (2.9%), posterolateral (1.4%) and posterior (1.4%) positions were also noted. Average distance of hypoglossal nerve was 27.7 (9.7) mm to carotid bifurcation, 9.3 (3.9) mm to hyoid bone, and 54.7 (18.0) mm to the inferior border of cricoid cartilage. CONCLUSION: In conclusion, our findings indicate that anatomic variations are not rare in the course of lower CNs within the neck in relation to adjacent structures, and awareness of these variations together with knowledge of distance to certain anatomic landmarks may help the surgeon to identify lower CNs during neck surgery and prevent potential nerve injuries.