螺旋CT尿道三维重建诊断后尿道狭窄或闭锁

目的 探讨螺旋CT尿道三维重建技术在后尿道狭窄或闭锁诊断中的应用价值.方法 对30例创伤性后尿道狭窄或闭锁患者术前行螺旋CT薄层扫描和尿道三维重建、X线尿道造影,观察狭窄或闭锁部位、长度以及尿道周围组织解剖结构的改变,并与开放性手术中发现的结果进行对比研究.结果 X线尿道造影检测狭窄或闭锁段长度为1.0～7.0 cm,平均4.0 cm,狭窄或闭锁长度相关系数为0.92,定位准确率为70%(21/30);螺旋CT尿道三维重建检测狭窄或闭锁段长度为1.2～7.6 cm,平均4.3 cm,狭窄或闭锁长度相关系数为0.96,定位准确率为93%(28/30);术中发现后尿道狭窄或闭锁长度为1.5～7.5 cm,平均4.2 cm.5例合并尿道直肠瘘者螺旋CT尿道三维重建可以清楚显示瘘管位置、长度及大小;X线尿道造影则无法清楚显示.结论 螺旋CT尿道三维重建对了解伤后尿道的解剖结构改变、测量尿道狭窄或闭锁部位和长度、指导手术方式选择有较高价值,尤其对合并尿道直肠瘘者有重要的诊断意义.

Application of 3-dimensional CT reconstruction in the diagnosis of posterior urethral strictures or ankylurethria

Objective To study the diagnostic value of 3-dimensional CT reconstruction in posterior urethral strictures or ankylurethria.Methods Thirty patients with strictures or ankylurethria of posterior urethra caused by pelvic fracture underwent helical CT scan and 3-dimensional reconstruction of the urethral canal as well as radiographic urethrography before and post open urethral reconstruction to observe the urethral anatomy,the length and position of the urethral strictures,the depth of periurethral scar.Results The mean stricture or ankylurethria length measured by radiographic urethrography was 4.0 cm (range from 1.0 cm to 7.0 cm),and the correlation coefficient of stricture or ankylurethria length was 0.92,21 (70%) patients were diagnosed accurately by radiographic urethrography.The mean stricture or ankylurethria length measured by 3-dimensional CT reconstruction was 4.3 cm (range from 1.2 cm to 7.6 cm),and the correlation coefficient of stricture or ankylurethria length was 0.96,there were 28(93%) patients diagnosed accurately by 3-dimensional CT reconstruction.The mean stricture or ankylurethria length measured by open urethral reconstruction was 4.2 cm (range from 1.5 cm to 7.5 cm).Five patients with urethrorectal fistula were also diagnosed accurately by 3-dimensional CT reconstruction rather than by radiographic urethrography.Conclusions 3-dimensional CT reconstruction of the urethral canal can accurately evaluate the urethral anatomy,the length and position of the urethral strictures,as well as the depth of periurethral scar after crush injury and provide useful information for operation that may not be provided by radiographic urethrography.3-dimensional CT reconstruction may become the most valuable means for detecting posterior urethra strictures or ankylurethria with urethrorectal fistula.