颈动脉内膜切除术相关喉上神经外侧支显微解剖研究简

目的通过对尸头标本喉上神经外侧支的显微解剖，探讨颈动脉内膜切除术中喉上神经外侧支的保护方法。方法解剖10具（20侧）尸头标本，平均年龄（54．43±4．08）岁。于手术显微镜下找到颈动脉鞘，在其内部探查迷走神经主干，并向上分离至喉上神经起点；然后沿喉上神经向下分离，仔细辨认喉上神经走行至其分叉部，再向下分离喉上神经外侧支至咽下缩肌表面，穿人咽下缩肌之前测量外侧支厚度。分别分离二腹肌、颈总动脉、颈内动脉、颈外动脉和甲状腺上动脉，显露以二腹肌后腹下缘为上界、颈外动脉内侧缘为外侧界、甲状腺上动脉上缘为下界的解剖三角区域，观察并统计喉上神经外侧支出现概率，测量喉上神经外侧支中点至乳突尖、下颌骨角和颈动脉分叉部间的距离。结果共10具（20侧）喉上神经外侧支厚度为（0．93±0．83）mm（0．72-1．15mm），其中1侧出现在解剖三角区域外，其余19侧均位于解剖三角区域内，出现概率为19／20；解剖三角区域内喉上神经外侧支中点位于下颌骨角后方（0．34±0．96）cm（．1．62-2．43cm）、下方（1．28±0．93）cm（-1．33～3．42cm），乳突尖前方（2．84±1．09）cm（0．51～5．14cm）、下方（4．51±0．76）cm（2．82-6．39cm），颈动脉分叉部前上方（1．64±0．89）cm（0．57．3．78cm，19／20）。结论在颈动脉内膜切除术中，以下颌骨角、乳突尖和颈动脉分叉部作为解剖标志，对于保护喉上神经外侧支具有重要临床意义。

Study on microsurgical anatomy of external branch of superior laryngeal nerve related to carotid endarterectomy

Objective To discuss how to protect external branch of superior laryngeal nerve （EBSLN） during carotid endarterectomy （CEA） by studying on microsurgical anatomy of EBSLN in cadaver head specimens. Methods Ten cadaver heads [20 sides, average age （54.43 ±4.08） years old] were studied by microsurgical anatomy. Skin as well as platysma was incised under the surgical microscope. Then sternocleidomastoid was retracted laterally. The origin of superior laryngeal nerve was found along the vagus nerve superiorly after it was discovered in the carotid sheath. The segment of superior laryngeal nerve from origin to bifurcation was carefully detached along the trunk of superior laryngeal nerve. Then EBSLN from bifurcation to the surface of inferior pharyngeal constrictor muscle where the nerve piercing in it was detached, and the thickness of the nerve was measured. Digastric muscle, common carotid artery （CCA）, internal carotid artery （ICA）, external carotid artery （ECA） and superior thyroid artery （SThA） were isolated to expose the triangle bounded superiorly by stylohyoid muscle, posteriorly by ECA, and anteriorly by SThA. The occurrence rate of EBSLN in this triangle was observed and recorded. The distance of this nerve segment with mastoid tip （MT） and angle of mandible （AM） as well as the bifurcation of common carotid artery （bCCA） was also measured. Results Nineteen sides of EBSLN were observed in the triangle, except one side. The occurrence rate of EBSLN in this triangle is 19/20, and the thickness of the nerve was （0.93 ± 0.83） mm （0.72-1.15 mm）. This nerve segment was （0.34 ±0.96） cm （-1.62-2.43 cm） posterior and （1.28 ±0.93） cm （-1.33-3.42 era） inferior to AM; （2.84 ±1.09） cm （0.51-5.14 cm） anterior and （4.51 ±0.76） cm （2.82-6.39 cm） inferior to MT; （1.64 ± 0.89） cm （0.57-3.78 cm） anterosuperior to bCCA （19/ 20）. Conclusions This triangle and other 3 anatomical landmarks （MT, AM and bCCA） are significant to find and protect EBSLN during CEA.