DO WOMEN WITH PROLAPSE HAVE LEVATOR ANI IMPAIRMENT?

盆腔器官脱垂(POP)发生的基本机制尚未建立。长期以来，人们一直假设提肛肌(LA)损伤与POP有关，但这一假设尚未得到验证。这项病例对照研究将检验Null假设，即盆腔器官脱垂的女性(病例)和支撑正常的女性(对照组)的肛提肌结构和功能是相同的。我们将研究150例女性盆腔器官脱垂，这些女性的盆腔器官脱垂延伸到处女膜环以下超过1厘米，以及150名无症状的对照组，他们的年龄、产次和种族都得到了证实的正常支持。曾接受过持久性有机污染物治疗的女性将被排除在外。将寻求病例和对照之间LA结构和功能的差异。洛杉矶结构和功能的测试：洛杉矶肌肉解剖中的结构异常将在高分辨率质子密度磁共振图像中进行量化。LA力量将在休息时和肌肉最大收缩时进行测量。目的I：检验病例和对照的MR图像中LA的耻骨内脏部分的解剖横截面积没有差异的零假设。目的2：检验病例组静息或最大收缩功能时左房肌力与对照组无差异的零假设。还将根据脱垂的大小和类型以及有无压力性尿失禁对提升肌的解剖和强度进行次级分析。将对可能导致脱垂的协变量进行分析，包括既往子宫切除、肥胖、雌激素状况、负重搬运和脱垂家族史。目的3：检验病例和对照组肌肉横截面积与左主肌力无相关性的零假设。这项研究的重要性在于它提供了关于POP女性存在的特定功能和解剖缺陷的基本见解，这将导致对这一常见疾病的改进研究。这些信息将指导未来的研究，并有助于设计更合理的治疗选择。

The basic mechanisms responsible for development of pelvic organ prolapse (POP) are not established. It has long been hypothesize that levator ani (LA) muscle impairment is associated with POP but this hypothesis has not been tested. This case control study will test the Null Hypothesis that levator ani muscle structure and function are the same in women with pelvic organ prolapse (cases) and women with normal support (controls). We will study 150 Cases who will be women with pelvic organ prolapse that extends more than 1 cm below the hymenal ring and 150 asymptomatic Controls with proven normal support matched for age, parity and race. Women with prior treatment for POP will be excluded. Differences in LA structure and function between cases and controls will be sought. Tests of LA structure and function: Structural abnormalities in LA muscle anatomy will be quantified in high-resolution proton density MR images. LA strength will be measured at rest and during maximum muscle contraction. Aim I: Test the null hypotheses that there are no differences in the anatomical cross-sectional area of the pubovisceral portion of the LA as seen in MR images of cases and controls. Aim 2: Test the null hypothesis that there is no difference in LA muscle strength at rest or during maximal contraction function in cases compared to controls. Sub analyses of levator anatomy and strength based on the size and type of the prolapse as well as the presence or absence of stress incontinence will also be carried out. Analysis of covariates possibly contributing to prolapse including prior hysterectomy, obesity, estrogen status, heavy lifting, and prolapse family history will be performed. Aim 3: Test the null hypothesis that muscle cross-sectional area is not correlated with LA strength for either cases or controls. The importance of this research lies in its providing fundamental insights about the specific functional and anatomical defects present in women with POP that will lead to improved research in this common disease. This information will guide future research as well as helping to devising more rational treatment selection.