Bertschinger Katharina M, Hetzer Frank H, Roos Justus E, Treiber Karl, Marincek Borut, Hilfiker Paul R
Institute of Diagnostic Radiology, University Hospital Zurich, Rämistrasse 100, CH-8091 Zurich, Switzerland.
Radiology. 2002 May;223(2):501-8. doi: 10.1148/radiol.2232010665.
To compare open-magnet magnetic resonance (MR) imaging performed with the patient sitting with dynamic closed-magnet MR imaging of the pelvic floor performed with the patient supine.
Thirty-eight patients underwent dynamic 1.5-T closed-magnet pelvic floor MR imaging while in the supine position. Midsagittal T2-weighted single-shot fast spin-echo and T1-weighted multiphase spoiled gradient-recalled-echo (SPGR) MR images were obtained before and after rectal contrast agent administration, respectively, with the patient at rest, straining, and maximally contracting the sphincter. Subsequently, the patient was transferred to an open 0.5-T system. Midsagittal multiphase T1-weighted SPGR MR images were then obtained every 2 seconds with the patient sitting while at rest, maximally contracting the sphincter, straining, and defecating. Images were analyzed with regard to presence of enteroceles, anterior rectoceles, intussusceptions, rectal descents, bladder descents, and vaginal vault descents.
All intussusceptions were missed at supine MR imaging. With sitting MR imaging as the reference standard, the sensitivity of supine MR imaging was 79% for depiction of bladder descents. When MR findings were graded and clinically irrelevant MR findings were excluded, sensitivity increased to 100% for depiction of bladder descents and anterior rectoceles and to 96% for depiction of rectal descents.
Dynamic supine MR imaging performed with a closed-configuration unit before and after rectal contrast agent administration appears to be an alternative to sitting MR defecography performed with an open-configuration unit for diagnosis of clinically relevant pelvic floor abnormalities.
比较患者坐位时进行的开放式磁体磁共振（MR）成像与患者仰卧位时进行的盆底动态封闭式磁体MR成像。
38例患者在仰卧位时接受了1.5-T动态封闭式磁体盆底MR成像。在直肠造影剂注射前后，分别于患者静息、用力及最大程度收缩括约肌时，获取矢状面T2加权单次激发快速自旋回波和T1加权多期扰相梯度回波（SPGR）MR图像。随后，患者被转移至开放式0.5-T系统。然后在患者坐位静息、最大程度收缩括约肌、用力及排便时，每隔2秒获取矢状面多期T1加权SPGR MR图像。对图像进行分析，观察有无肠膨出、直肠前膨出、套叠、直肠下移、膀胱下移及阴道穹隆下移。
仰卧位MR成像时所有套叠均未被发现。以坐位MR成像作为参考标准，仰卧位MR成像对膀胱下移的显示敏感性为79%。当对MR表现进行分级并排除临床无关的MR表现时，仰卧位MR成像对膀胱下移和直肠前膨出的显示敏感性增至100%，对直肠下移的显示敏感性增至96%。
直肠造影剂注射前后使用封闭式设备进行的仰卧位动态MR成像，似乎可替代使用开放式设备进行的坐位MR排粪造影，用于诊断临床相关的盆底异常。
