Toozs-Hobson P, Khullar V, Cardozo L
Department of Urogynaecology, King's College Hospital, London, UK.
Ultrasound Obstet Gynecol. 2001 May;17(5):421-4. doi: 10.1046/j.1469-0705.2001.00354.x.
To measure urethral sphincter volume by three-dimensional (3D) ultrasound. To assess the reproducibility of this measurement technique and to compare volumes obtained using 3D ultrasound with volumes calculated from a formula based on 2D ultrasound measurements.
Women were recruited as part of an ongoing study of changes to the pelvis resulting from pregnancy and childbirth. One hundred and eleven women in the third trimester of pregnancy (between 32 and 41 completed weeks' gestation) underwent a 3D transvaginal ultrasound scan of the urethra. In 10 cases the scan was analyzed twice by different observers to assess the reproducibility of the measurements from the scans and the results were analyzed using limits of agreement.
The interobserver error was consistent between all the linear, 2D and 3D measurements obtained from the area scanned. There was a significant difference between volumes calculated directly by 3D ultrasound and the approximated volumes from conventional 2D measurements.
Three-dimensional ultrasound appears to be a useful tool in measuring urethral sphincter volume. The error is consistent with that of linear and 2D imaging. However, the increase in normal range generated by biological variation in all three planes makes 3D ultrasound a more sensitive method of evaluating change to the urethral sphincter.
通过三维（3D）超声测量尿道括约肌体积。评估该测量技术的可重复性，并将3D超声获得的体积与基于二维（2D）超声测量的公式计算得出的体积进行比较。
招募女性参与一项正在进行的关于妊娠和分娩导致骨盆变化的研究。111名妊娠晚期（妊娠32至41足周）的女性接受了尿道的3D经阴道超声扫描。在10例病例中，由不同观察者对扫描进行了两次分析，以评估扫描测量的可重复性，并使用一致性界限分析结果。
从扫描区域获得的所有线性、2D和3D测量之间的观察者间误差是一致的。3D超声直接计算的体积与传统2D测量的近似体积之间存在显著差异。
三维超声似乎是测量尿道括约肌体积的有用工具。该误差与线性和2D成像的误差一致。然而，所有三个平面中的生物变异所产生的正常范围增加，使得3D超声成为评估尿道括约肌变化的更敏感方法。
