Nolte-Ernsting Claus, Glowinski Arndt, Schaeffter Tobias, Adam Gerhard, Günther Rolf W
Department of Diagnostic and Interventional Radiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany.
Invest Radiol. 2003 Oct;38(10):617-24. doi: 10.1097/01.rli.0000077123.33090.d9.
To approach the concept of magnetic resonance (MR) imaging-monitored micturating cystourethrography (MRMCU) by using gadolinium-enhanced real-time MR fluoroscopy.
MRMCU was performed in 21 male patients (27-76 years) subsequent to gadolinium excretory MR urography. Patients were examined in supine position at 1.5 T. For MR fluoroscopy of the urethra during micturition, we used a T1-weighted single-slice gradient-echo sequence with continuous radial k-space acquisition. Image reconstruction was obtained with the sliding-window technique reaching a frame rate of 25/s. The image plane was guided interactively through the urethra, the bladder and the ureters without stopping the scan.
Two patients were unable to void in supine position. With MR fluoroscopy, the flow of gadolinium-enhanced urine through the urethra was visualized in 19 patients, in 14 of whom with complete demonstration of the urethral anatomy subdivided into 5 segments. Four urethral segments were identified in 1 patient, 3 segments in 2 patients, 2 segments in 3 patients, and 1 segment in 1 patient. MRMCU demonstrated changes in the urethral anatomy and the urine flow in 2 patients with a neobladder and in 1 patient with hypertrophy of the prostate. Subject to the limitation of antegrade gadolinium application, interactive MRMCU allowed to determine whether the ureters were enhanced by gadolinium or not.
Gadolinium-enhanced MR fluoroscopy using radial k-space acquisition has achieved complete demonstration of the segmental anatomy of the urethra in 74% of the male adult patients who were able to accomplish micturition. Although MR fluoroscopy was able to visualize the gadolinium-enhanced ureters, the current data do not permit to conclude that MRMCU can demonstrate vesicoureteral reflux, especially in children.
通过使用钆增强实时磁共振荧光透视法探讨磁共振（MR）成像监测的排尿性膀胱尿道造影（MRMCU）的概念。
在钆排泄性MR尿路造影后，对21例男性患者（27 - 76岁）进行MRMCU检查。患者在1.5T磁场下仰卧位接受检查。在排尿过程中对尿道进行MR荧光透视时，我们使用了具有连续径向k空间采集的T1加权单层面梯度回波序列。采用滑动窗口技术进行图像重建，帧率达到25帧/秒。在不停止扫描的情况下，通过交互式操作将图像平面引导穿过尿道、膀胱和输尿管。
2例患者在仰卧位时无法排尿。通过MR荧光透视，19例患者可见钆增强尿液通过尿道的流动，其中14例患者的尿道解剖结构被完整显示并分为5个节段。1例患者显示4个尿道节段，2例患者显示3个节段，3例患者显示2个节段，1例患者显示1个节段。MRMCU显示了2例新膀胱患者和1例前列腺增生患者的尿道解剖结构和尿液流动的变化。由于顺行性钆应用的限制，交互式MRMCU能够确定输尿管是否被钆增强。
使用径向k空间采集的钆增强MR荧光透视法在74%能够完成排尿的成年男性患者中实现了尿道节段解剖结构的完整显示。尽管MR荧光透视能够显示钆增强的输尿管，但目前的数据尚不能得出MRMCU能够显示膀胱输尿管反流的结论，尤其是在儿童中。
