三维超声对不同状态下女性盆膈裂孔及耻骨直肠肌的观察

Observation of levator hiatus and puborectalis in different conditions by three-dimensional ultrasound

目的应用三维超声分别在静息期、张力期和缩肛期观察未育女性耻骨直肠肌和盆膈裂孔的形态学变化并进行相关分析,以期寻找一种简便有效的观察女性盆底形态学变化的影像学方法。方法选取2011年9月至2012年4月于上海交通大学附属第六人民医院妇产科就诊的70例未育女性患者,分别在静息期、张力期和缩肛期行盆底三维超声检查并对三维重建声像图进行分析,观察不同状态下盆膈裂孔的形态及内部解剖构成,测量耻骨直肠肌厚度和后角以及盆膈裂孔的前后径、左右径和面积。采用配对t检验分别比较耻骨直肠肌厚度、后角大小、盆膈裂孔前后径、左右径、面积差异。结果 70例未育女性患者在静息期、张力期和缩肛期3种不同状态下,盆膈裂孔的形态以及内部解剖结构无明显变化,而裂孔大小以及耻骨直肠肌厚度和后角大小发生较明显改变:静息期、张力期和缩肛期测得耻骨直肠肌厚度分别为(6.64±0.73)mm、(6.48±0.12)mm和(6.89±0.25)mm,耻骨直肠肌后角分别为(64.81±8.27)°、(71.96±9.36)°和(69.94±7.88)°,盆膈裂孔前后径分别为(4.29±0.67)cm、(4.54±0.79)cm和(4.01±0.85)cm,盆膈裂孔左右径分别为(3.70±0.61)cm、(3.96±0.65)cm和(3.47±0.49)cm,盆膈裂孔面积分别为(11.25±2.56)cm2、(14.48±4.51)cm2和(9.23±2.53)cm2。与静息期相比,张力期耻骨直肠肌变薄,后角变大,盆膈裂孔前后径、左右径及面积变大,差异均有统计学意义(t值分别为2.56、-3.58、-2.91、-3.12、-5.07,P均<0.001);与静息期相比,缩肛期耻骨直肠肌变厚,后角变大,盆膈裂孔前后径、左右径及面积变小,差异均有统计学意义(t值分别为-3.01、-2.70、3.88、3.21、4.39,P均<0.001)。结论三维超声可动态观察不同状态下盆膈裂孔和耻骨直肠肌的形态学改变,是观察女性盆底形态学改变的最佳影像学方法之一。

Objective To evaluate the morphological alternations of levator hiatus and puborectalis in different conditions using three-dimensional ( 3D) ultrasound,and to provide a convenient and effective imaging method to observe the morphological alternation of female pelvic floor. Methods Totally 70 nulliparous women in Department of Gynaecology and Obstetrics,Shanghai Jiaotong University Affiliated Sixth People's Hospital from September 2011 to April 2012 underwent translabial 3D ultrasound at rest,on levator ani muscle contraction and during maximum Valsalva maneuver. The morphology and internal anatomical structures of levator hiatus were observed,the thickness and angle of puborectalis and the size of levaor hiatus were measured in the minimum hiatal dimension during three maneuvers. Results The morphology and internal anatomical structures of levator hiatus showed no notable alternations at rest,on levator ani muscle contraction and during maximum Valsalva maneuver,the size of levator hiatus and the thickness and angle of puborectalis changed significantly during the three maneuvers: the thickness and angle of puborectalis were ( 6. 64 ± 0. 73) mm and ( 64. 81 ± 8. 27) °; ( 6. 48 ± 0. 12) mm and ( 71. 96 ± 9. 36) °; ( 6. 89 ± 0. 25) mm and ( 69. 94 ± 7. 88) °,respectively,and there were significant differences among different conditions ( t = 2. 56,- 3. 58, - 3. 01, - 2. 70,all P < 0. 001) . The anteroposterior diameter ( AP) ,left to right diameter( LR) and area of the levator hiatus( HA) were ( 4. 29 ±0. 67) cm,( 3. 70 ±0. 61) cm and ( 11. 25 ± 2. 56) cm2 at rest. During the maximum Valsalva maneuver,AP,LR and HA were ( 4. 54 ± 0. 79) cm,( 3. 96 ± 0. 65) cm and ( 14. 48 ± 4. 51) cm2. AP,LR and HA were measured as ( 4. 01 ±0. 85) cm,( 3. 47 ±0. 49) cm and ( 9. 23 ±2. 53) cm2 on levator ani muscle contraction. There were significant differences among different conditions ( t = - 2. 91,- 3. 12,- 5. 07,3. 88,3. 21,4. 39, all P < 0. 001) . The size of levator hiatus was larger,the angle of puborectalis was bigger and the puborectalis was thinner during maximum Valsalva maneuver as compared to the condition at rest. While on levator ani muscle contraction,the levator hiatus showed adverse alternations as compared to the maximum Valsalva maneuver,except for the angle of puborectalis,which is bigger than that at rest. Conclusions The morphological alternations of levator hiatus and puborectalis in different conditions of nulliparous women could be dynamically observed using 3D ultrasound. Three - dimensional ultrasound is one of the optimum imaging methods in observing the morphological alternations of female pelvic floor.