Department of Imaging, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil, 1211 Geneva 14, Switzerland.
Radiology. 2012 Feb;262(2):538-43. doi: 10.1148/radiol.11111014. Epub 2011 Dec 20.
To determine levator ani muscle complex anatomic findings in nulliparous patients at magnetic resonance (MR) imaging examinations performed with opacification of the vagina and rectum with ultrasonographic gel.
The institutional review board approved this retrospective study, and the informed consent requirement was waived. Findings from pelvic MR imaging examinations with double opacification in 123 consecutive nulliparous patients (mean age, 32.13 years; age range, 17-45 years) who were suspected of having endometriosis were reviewed. The pubococcygeal muscles were analyzed on coronal sections obtained through the middle part of the vagina, perineal body, and anal canal. The puborectalis muscles were analyzed on coronal sections obtained through the perineal body. The iliococcygeal muscles were analyzed on coronal sections obtained through the rectum. Miscellaneous findings such as visibility of deep transverse muscles of the perineum, perineal body, and focal muscle defects were also noted.
In 56% (69 of 123) of patients, at least one morphologic variant (thinning or aplasia) of a muscle of the levator ani complex was noted. Variants of puborectalis muscles were noted in 6% of patients. Variants of iliococcygeal muscles were noted in 13%. Variants of pubococcygeal muscles were noted in 32% at the anal canal level, in 49% at the perineal body level, and in 49% at the vaginal level. Variants of pubococcygeal muscles were noted on the left side in 53 patients (77% of pubococcygeal muscle variants).
Numerous morphologic variants of the levator ani muscle complex are noted at coronal thin-section MR imaging with double opacification. Most involve the pubococcygeal muscle on the left side at perineal body and vaginal levels. Whether some of these anatomic findings may favor prolapse after vaginal birth may be questioned.
在经阴道和直肠超声凝胶双重造影的磁共振成像（MR）检查中，确定未产妇的肛提肌复合体解剖学发现。
该机构审查委员会批准了这项回顾性研究，并且豁免了知情同意书的要求。对 123 例连续的疑似患有子宫内膜异位症的未产妇（平均年龄 32.13 岁；年龄范围 17-45 岁）进行经阴道和直肠双重造影的盆腔 MR 成像检查，对这些检查的结果进行了回顾性分析。在通过阴道中段、会阴体和肛门管获得的冠状切片上分析耻骨尾骨肌，在通过会阴体获得的冠状切片上分析耻骨直肠肌，在通过直肠获得的冠状切片上分析髂尾骨肌。还注意到其他各种发现，如会阴深横肌、会阴体和局灶性肌肉缺陷的可见性。
在 56%（69/123）的患者中，至少有一个肛提肌复合体肌肉的形态变异（变薄或发育不全）。6%的患者存在耻骨直肠肌变异，13%的患者存在髂尾骨肌变异。在肛门管水平，32%的患者存在耻骨尾骨肌变异，在会阴体水平，49%的患者存在耻骨尾骨肌变异，在阴道水平，49%的患者存在耻骨尾骨肌变异。在 53 名患者（耻骨尾骨肌变异的 77%）中，左侧耻骨尾骨肌变异。
在经阴道和直肠双重造影的冠状薄层 MR 成像中，可观察到肛提肌复合体的多种形态变异。大多数变异发生在会阴体和阴道水平的左侧耻骨尾骨肌。这些解剖学发现中的一些是否可能有利于阴道分娩后的脱垂，这可能值得质疑。
