Abstract：
OBJECTIVE: The aim of this systematic review and meta-analysis was to systematically review and perform a meta-analysis on the anatomical variations of the RLN.
METHODS: We performed online research for studies that addressed anatomical variations of the RLN and laterality, published between 2015 and 2021. We found 230 articles, and nine were included.
RESULTS: Eight variations were found, with Type I prevailing (41.17%; 95% CI 19.44-64.88), extra laryngeal divergence of the RLN. The other types were: II-fan shape; III-distance greater than 5 mm to the cricothyroid joint; IV-thickening and adipopexy in the elderly; V-non-recurrent laryngeal nerve; VI-intracranial branch; VII-tortuous ascending RLN; and VIII-combination between the inferior branch of the NV and the ascending trunk of the RLN. Types I (p = 0) and III (p < 0.01) prevailed on the left and types II (p < 0.01) and V (p < 0.01) on the right.
CONCLUSIONS: It was observed that variations occurred due to the path of the RLN to the entrance to the larynx, its shape, and the age of the evaluated individual. The most frequent variation and side were, respectively, Type I, extra laryngeal divergence and left.
METHODS: We performed online research for studies that addressed anatomical variations of the RLN and laterality, published between 2015 and 2021. We found 230 articles, and nine were included.
RESULTS: Eight variations were found, with Type I prevailing (41.17%; 95% CI 19.44-64.88), extra laryngeal divergence of the RLN. The other types were: II-fan shape; III-distance greater than 5 mm to the cricothyroid joint; IV-thickening and adipopexy in the elderly; V-non-recurrent laryngeal nerve; VI-intracranial branch; VII-tortuous ascending RLN; and VIII-combination between the inferior branch of the NV and the ascending trunk of the RLN. Types I (p = 0) and III (p < 0.01) prevailed on the left and types II (p < 0.01) and V (p < 0.01) on the right.
CONCLUSIONS: It was observed that variations occurred due to the path of the RLN to the entrance to the larynx, its shape, and the age of the evaluated individual. The most frequent variation and side were, respectively, Type I, extra laryngeal divergence and left.
摘要：
目的：本系统综述和荟萃分析的目的是对RLN的解剖变异进行系统综述和荟萃分析。
方法：我们进行了在线研究，以解决RLN和侧向性的解剖变异，在2015年至2021年之间发布。我们找到了230篇文章,其中9人。
结果：发现了八个变化，I型占优（41.17%；95%CI19.44-64.88），RLN的喉外发散。其他类型是：II扇形；距环甲关节的III距离大于5毫米；老年人的IV增厚和脂肪增生；V-非返喉神经；VI-颅内支；VII-曲折上升的RLN；以及NV下支与RLN上升干之间的VIII组合。左侧为I型（p=0）和III型（p<0.01），右侧为II型（p<0.01）和V型（p<0.01）。
结论：观察到由于RLN到喉入口的路径而发生了变化，它的形状,和被评估个人的年龄。最常见的变化和侧面是，分别,I型,额外的喉部发散和左边。
方法：我们进行了在线研究，以解决RLN和侧向性的解剖变异，在2015年至2021年之间发布。我们找到了230篇文章,其中9人。
结果：发现了八个变化，I型占优（41.17%；95%CI19.44-64.88），RLN的喉外发散。其他类型是：II扇形；距环甲关节的III距离大于5毫米；老年人的IV增厚和脂肪增生；V-非返喉神经；VI-颅内支；VII-曲折上升的RLN；以及NV下支与RLN上升干之间的VIII组合。左侧为I型（p=0）和III型（p<0.01），右侧为II型（p<0.01）和V型（p<0.01）。
结论：观察到由于RLN到喉入口的路径而发生了变化，它的形状,和被评估个人的年龄。最常见的变化和侧面是，分别,I型,额外的喉部发散和左边。
