Menon Riju R, Murali Sreedutt, Nair C Gopalakrishnan, Babu Misha J C, Jacob Pradeep
Department of General Surgery, Amrita School of Medicine, Amrita Vishwa Vidyapeetham, Kochi, Kerala, India.
Indian J Endocrinol Metab. 2017 Nov-Dec;21(6):845-847. doi: 10.4103/ijem.IJEM_230_17.
INTRODUCTÍON: Goiter is a very common problem dealt with by surgeons. Surgical treatment of thyroid requires removal of a part (hemi) or whole of the gland (total thyroidectomy). The external branch of the superior laryngeal nerve (EBSLN) is an important but less researched structure to be preserved during surgery. Various studies have described the incidence of different types of EBSLN, but have not described regarding the relationship between the change in volume of the gland to the nerve.
A prospective analysis of 100 patients who underwent total thyroidectomy in our department was done. All patients underwent preoperative ultrasonography and the volume of the gland was calculated. Intraoperatively, the EBSLN was identified and preserved prior to ligating the superior thyroid vessels. The nerve was classified as per the Cernea classification. The gland was divided into high and low volume, taking 20 ml as the cutoff. The incidence of Type 2 nerve in a low-volume gland was compared with that of a high-volume gland.
In 100 patients (200 nerves), 191 nerves were identified. The nerve was type 1 in 56/200 (28%), Type 2a in 116/200 (58%), and Type 2b in 19/200 (9%) patients. In large-volume glands, Type 2 nerve was more common (87%).
Dissection of thyroid gland requires expertise to preserve the EBSLN. Large volume glands pose a more difficult challenge, as the gland is more closer to the nerve.
甲状腺肿是外科医生常处理的一个非常常见的问题。甲状腺手术治疗需要切除部分（半侧）或整个腺体（全甲状腺切除术）。喉上神经外支（EBSLN）是手术中需要保留的一个重要但研究较少的结构。各种研究描述了不同类型EBSLN的发生率，但未描述腺体体积变化与该神经之间的关系。
对在我科接受全甲状腺切除术的100例患者进行前瞻性分析。所有患者术前行超声检查并计算腺体体积。术中，在结扎甲状腺上血管之前识别并保留EBSLN。根据塞尔尼亚分类法对神经进行分类。以20ml为界值将腺体分为高体积和低体积。比较低体积腺体和高体积腺体中2型神经的发生率。
100例患者（200条神经）中，识别出191条神经。56/200（28%）例患者的神经为1型，116/200（58%）例为2a型，19/200（9%）例为2b型。在大体积腺体中，2型神经更常见（87%）。
甲状腺解剖需要专业技能来保留EBSLN。大体积腺体带来的挑战更大，因为腺体更靠近神经。
