远外侧入路中枕髁相关解剖学参数的CT影像研究

目的探讨正常成人枕髁相关解剖学参数的CT影像测量,为远外侧入路手术中枕髁的处理提供解剖学依据。方法回顾性分析2018年9月—2019年3月新乡医学院第一附属医院影像资料库中335例正常成人头颈CTA影像资料,应用Mimics软件对枕髁进行三维重建后,在图像下面观标出:枕骨大孔前缘中点(A)、枕骨大孔后缘中点(B)、枕髁后缘和枕骨大孔后缘交点(C)、舌下神经管内口后缘中点(D)等定位点,分别测量枕髁两侧A、B点连线与A、C点连线的夹角(∠α),A、B点连线与A、D点连线的夹角(∠β),CD两点之间的长度,枕髁前后径长度,以及∠β和∠α差值。采用配对样本t检验比较不同侧别间上述测量指标的差异。结果335例正常成人两侧合计检测结果:∠α为32.49°~52.18°(42.06°±3.25°)、∠β为43.62°~73.48°(58.51°±5.37°),∠β和∠α差值为7.42°~30.10°(16.45°±4.07°);CD长度为6.18~13.08(8.94±1.33)mm;枕髁前后径长度为16.12~27.71(21.57±2.17)mm。枕髁左侧、右侧∠α为42.12°±2.88°、42.00°±3.59°,∠β为59.37°±5.24°、57.66°±5.39°,∠β和∠α差值为17.24°±4.13°、15.66°±3.87°,CD长度为(9.14±1.39)mm、(8.73±1.23)mm,枕髁前后径长度为(21.59±2.28)mm、(21.55±2.08)mm。不同侧别间比较:左侧∠β、∠β与∠α差值、CD长度均大于右侧,差异均有统计学意义(t=4.402、5.971、4.199,P值均<0.05);而∠α、枕髁前后径长度不同侧别间差异均无统计学意义(P值均>0.05)。结论不同侧别间枕髁的相关解剖学影像测量数据存在差异;远外侧入路中,磨除从枕髁后缘至舌下神经管内口范围的骨质所暴露的视野及扩大的视角,在左侧均大于右侧。因此,对于枕骨大孔腹侧正中病变,建议从左侧开颅,可获得更大的暴露范围。

CT imaging study of anatomical parameters related to occipital condyle in the far lateral approach

Objective To explore the CT image measurement of the anatomical parameters of the occipital condyle in normal adults, and to provide an anatomical basis for the treatment of the occipital condyle in the far lateral approach.Methods The imaging data of 335 normal adults with head and neck CTA in the imaging database of the First Affiliated Hospital of Xinxiang Medical University from September 2018 to March 2019 were analyzed retrospectively. After three-dimensional reconstruction of occipital condyle with Mimics software, the positioning points of the midpoint of anterior edge of foramen magnum (A), the midpoint of posterior edge of foramen magnum (B), the posterior edge of occipital condyle and posterior edge of foramen magnum (C) and the midpoint of posterior edge of internal orifice of hypoglossal nerve canal (D) were marked. The ∠α that was between the line connecting point A and point B and the line connecting point A and point C, the ∠β between the line connecting point A and point B and the line connecting point A and point D and the length between point C and point D and the anteroposterior diameter length of occipital condyle were measured. The difference between ∠β and ∠α was calculated. The paired sample t-test was used to compare the differences of the above measurements between different sides.Results Total measurements on both sides of 335 normal adults, ∠α was 32.49°-52.18° (42.06°±3.25°), ∠β was 43.62°-73.48° (58.51°±5.37°), the difference between ∠β and ∠α was 7.42°-30.10° (16.45°±4.07°); the length of CD was 6.18-13.08 (8.94±1.33)mm, the anteroposterior diameter length of occipital condyle was 16.12-27.71 (21.57±2.17)mm. ∠α was 42.12° ± 2.88° on the left and 42.00° ± 3.59° on the right. ∠β was 59.37° ± 5.24° on the left, and 57.66° ± 5.39° on the right. The difference between ∠β and ∠α was 17.24° ± 4.13° on the left, and 15.66° ± 3.87° on the right. The length of CD was (9.14 ± 1.39) mm on the left side and (8.73 ± 1.23) mm on the right side. The anteroposterior diameter length of occipital condyle was (21.59 ± 2.28) mm on the left side and (21.55 ± 2.08) mm on the right side. Comparison between different sides: the measured values of ∠β,the difference between∠β and∠α, the length of CD on the left side were higher than those on the right side, and the differences were statistically significant (t=4.402, 5.971, 4.199, all P values＜0.05). There was no significant difference between the∠α and the anteroposterior diameter length of occipital condyle (all P values＞0.05).Conclusions There are differences in anatomical measurement data of normal occipital CT images between different sides. The bone from the posterior edge of the occipital condyle to the internal orifice of the hypoglossal nerve canal is removed in the far lateral approach, and the surgical field and enlarged visual angle on the left side are larger than those on the right side. For the ventral median lesion of occipital foramen, it is suggested that craniotomy from the left can obtain a larger exposure range.