两种全子宫切除术后阴道三维轴向及承受腹压力学应变改变情况可视化研究

Visualization of three-dimensional axial and abdominal pressure strain of the vagina after two kinds of total hysterectomy

目的通过磁共振成像(MRI)可视化探究广泛性全子宫切除术(RH)与普通全子宫切除术(TH)后阴道三维轴向及承受腹压力学应变改变情况。方法按纳入标准选择2019年5月至2020年9月就诊于南方医科大学南方医院行RH的子宫颈鳞癌或腺癌患者50例,同期行TH的良性疾病或Ⅰ期子宫内膜癌患者30例,分别于术前、术后1年行盆腔MRI检查。在矢状面以耻骨联合下缘为坐标原点建立坐标系统,将耻尾线(pubococcygeal line,PCL)设为X轴、与该线垂直方向为Y轴,利用MRI三维重建技术分别重建出骨盆、阴道。定义术前、术后阴道拐点为受力点P1、P2,P1点在术后阴道对应点为P1’点,分别测量P1、P1’、P2点坐标位置,阴道上下段角度及该点阴道下段/阴道总长度比值。结果(1)RH组受力点位置及力学应变改变情况:术后P2相对术前P1向下0.75cm更靠近阴道外口、向前0.63cm更靠近耻骨联合;术后P2阴道上下夹角均较术前P1更钝,角度增加17.62°;P1、P2点处阴道下段长度与阴道总长度的比值分别为0.47±0.06和0.54±0.09(P<0.001)。(2)TH组受力点位置及力学应变改变情况:术后P2位置较术前P1向下0.35cm更靠近阴道外口、向前0.50cm更靠近耻骨联合;术后P2阴道上下夹角均较术前P1更钝,角度增加15.91°;P1、P2点处阴道下段长度与阴道总长度的比值分别为0.43±0.59和0.48±0.84(P=0.072)。(3)两组术前、术后阴道下段长度差值RH组大于TH组(P=0.002),阴道角度变化及阴道下段长度与阴道总长度的比值的差值对比差异均无统计学意义(均P>0.05)。结论术后早期RH及TH均可导致阴道前倾、变直,阴道受力点位置下移,RH后阴道受力点位置较TH后更向前靠近耻骨联合,向下靠近阴道外口,术后受力点P2处阴道上下段角度更钝。

Objective To compare the three-dimensional axial and abdominal pressure strain of the vagina after radical hysterectomy(RH)and total hysterectomy(TH)through magnetic resonance imaging visualizaion.Methods Fifty cervical cancer patients treated with RH in Nanfang Hospital of Southern Medical University from May 2019 to September 2020 were included,and 30 patients treated with TH during the same period were included;they received pelvic MRI examination before and 1 year after surgery,respectively.On the sagittal plane,the coordinate system was established with the lower margin of the pubic symphysis as the origin,and the pubococcygeal line(PCL)was set as the X axis and the vertical direction of PCL as the Y axis.The pelvis and vagina were reconstructed by MRI 3D reconstruction technology.The vaginal inflection points before and after surgery were defined as points P1 and P2,and the corresponding point of P1 in the vagina after surgery was P1’.The coordinate positions of points P1,P1’and P2,the angle of upper and lower vaginal segments,and the ratio of the lower vaginal segment to the total length of the vagina at this point were measured respectively.Results(1)RH stress point location and mechanical strain changes:compared with P1 before surgery,P2 was closer to the vaginal orifice 0.75cm downward and closer to the symphysis pubis 0.63cm forward;the angle between upper and lower vagina of P2 after surgery was blunter than that of P1 before surgery,and the angle increased by 17.61°.The ratio of lower vaginal segment to total length at P1 and P2 was0.47±0.06 and 0.54±0.09(P<0.001),respectively.(2)The position of TH stress point and the change of mechanical strain:P2 was 0.35cm lower and closer to the vaginal orifice and 0.50cm forward and closer to the symphysis pubis than the P1 before surgery.The angle between upper and lower vagina of P2 after surgery was blunter than that of P1 before surgery,and the angle increased by 15.92°.The ratio of lower vaginal segment to total length at P1 and P2 was 0.43±0.59and 0.48±0.84(P=0.072),respectively.(3)RH was greater than TH before and after surgery in the difference of lower vaginal segment(P=0.002);there was no statistical significance in the differences of vaginal angle or the ratio of lower vaginal segment to total vaginal length(P>0.05).Conclusion RH and TH in the early postoperative period can lead to the vagina leaning forward and straighening,and the position of the vaginal stress point moves downward.Compared with TH,the position of the vaginal stress point after RH is closer to the symphysis pubis and closer to the vaginal orifice,and the angle of the upper and lower vaginal segments at the postoperative stress point P2 is blunter.