Unterweger M, Marincek B, Gottstein-Aalame N, Debatin J F, Seifert B, Ochsenbein-Imhof N, Perucchini D, Kubik-Huch R A
Institute of Diagnostic Radiology, University Hospital, Rämistr. 100, CH-8091 Zurich, Switzerland.
AJR Am J Roentgenol. 2001 Apr;176(4):959-63. doi: 10.2214/ajr.176.4.1760959.
The aim of this study was to compare pelvic floor anatomy and laxity at rest and on straining (Valsalva's maneuver) using dynamic ultrafast MR imaging in women who were continent versus those with stress incontinence differing in obstetric history.
Thirty continent women were divided into three equal groups (nulliparous, previous cesarean delivery, previous vaginal delivery) and compared with 10 women with stress-incontinence with a history of at least one vaginal delivery. MR imaging of the pelvic floor at rest and on maximal strain was performed, using axial T2-weighted fast spin-echo images followed by sagittal ultrafast T2-weighted single-shot fast spin-echo sequences. Mean population age (age range, 22-45 years; mean +/- SD, 36 +/- 5.4 years), was similar in the four groups, as was parity in the three parous groups.
Mean distances between the bladder floor and pubococcygeal line at rest did not differ between the four groups. On straining, bladder floor descent was 1.1 +/- 0.9, 1.0 +/- 1.1, and 1.9 +/- 0.9 cm in continent nulliparous, cesarean delivery, and vaginal delivery women, respectively, versus 3.2 +/- 1.0 cm in incontinent women (p = 0.0005). Cervical descent was greater in incontinent versus nulliparous women (p = 0.0019). Bladder floor descent was greater in the continent vaginal delivery group than in continent cesarean delivery control patients (p = 0.04). In patients with stress incontinence, symptoms did not correlate with amplitude of descent. The right levator muscle was thinner overall than the left, regardless of frequency direction (p = 0.001).
Ultrafast MR imaging using the T2-weighted single-shot fast spin-echo sequence allows dynamic evaluation of the pelvic compartments at maximal strain with no need for contrast medium. Pelvic floor laxity and supporting fascia abnormalities were most common in patients with stress incontinence followed by continent women with a history of vaginal delivery. The results are therefore compatible with the hypothesis of vaginal delivery as a contributory factor to stress incontinence in older parous women.
本研究旨在使用动态超快磁共振成像，比较无尿失禁女性与有压力性尿失禁且产科病史不同的女性在静息状态和用力时（瓦尔萨尔瓦动作）的盆底解剖结构及松弛情况。
30名无尿失禁女性被分为三个相等的组（未生育、既往剖宫产、既往阴道分娩），并与10名有压力性尿失禁且至少有一次阴道分娩史的女性进行比较。使用轴向T2加权快速自旋回波图像，随后进行矢状面超快T2加权单次激发快速自旋回波序列，对静息状态和最大用力时的盆底进行磁共振成像。四组的平均人群年龄（年龄范围22 - 45岁；平均±标准差，36±5.4岁）相似，三个经产妇组的产次也相似。
四组在静息状态下膀胱底部与耻骨尾骨线之间的平均距离无差异。用力时，无尿失禁的未生育、剖宫产和阴道分娩女性的膀胱底部下降分别为1.1±0.9、1.0±1.1和1.9±0.9厘米，而有尿失禁女性为3.2±1.0厘米（p = 0.0005）。有尿失禁女性的宫颈下降比未生育女性更大（p = 0.0019）。无尿失禁的阴道分娩组的膀胱底部下降比无尿失禁的剖宫产对照组患者更大（p = 0.04）。在有压力性尿失禁的患者中，症状与下降幅度无关。无论频率方向如何，右侧提肌总体上比左侧更薄（p = 0.001）。
使用T2加权单次激发快速自旋回波序列的超快磁共振成像能够在无需造影剂的情况下，对最大用力时的盆腔区域进行动态评估。盆底松弛和支持筋膜异常在有压力性尿失禁的患者中最为常见，其次是有阴道分娩史的无尿失禁女性。因此，研究结果与阴道分娩是导致老年经产妇压力性尿失禁的一个促成因素这一假设相符。
