颜璨?曹亚先?王海玉?刘金蓉?王哲?王红英

【摘要】目的 總结胎儿一穴肛畸形（CM）产前超声及MRI的图像特征。方法 回顾性分析经产前系统超声初筛疑似CM的8例胎儿的临床影像资料，并与出生或引产后结果进行对照，总结其产前影像学特征，追踪胎儿妊娠结局。结果 经产后或引产后证实CM 5例，均于孕晚期发现，产前超声误诊3例，产前MRI漏诊1例。产前超声主要表现为肛门闭锁（5例）、盆腹腔中线位置囊肿（4例）、外生殖器模糊（3例）、双肾积水（3例）、肠管扩张（2例）、肠管回声增强（1例）。产前MRI检查示直肠未探及粪便高信号影（4例）、盆腹腔囊状信号影（4例）。孕妇引产2例，活产3例。5例CM胎儿会阴部仅有一个开口，肛门闭锁，外生殖器为女性外观，2例术中见三腔室汇合成1个共同通道开口于会阴。结论 肛门闭锁、盆腹腔中线部位囊肿是CM产前超声的特征性表现，当提示外生殖器异常、泌尿系统积水及肠道钙化斑时有助于诊断CM。MRI较超声更能清晰显示盆腔三个腔室之间的关系及直肠情况。

【关键词】产前诊断;超声;磁共振成像;一穴肛畸形

Diagnostic value of prenatal ultrasound combined with MRI in fetal cloacal malformations Yan Can， Cao Yaxian， Wang Haiyu， Liu Jinrong， Wang Zhe， Wang Hongying. Department of Ultrasound， Guangzhou Women and Childrens Medical Center， Guangzhou 510623， China

Corresponding author， Wang Hongying， E-mail： why0118@ 163. com

【Abstract】Objective To illustrate the imaging features of fetal cloacal malformations （CM） by ultrasound combined with magnetic resonance imaging （MRI）. Methods Clinical imaging characteristics of 8 fetuses suspected with CM by prenatal systematic ultrasound screening were retrospectively analyzed， and compared with the postpartum results. Prenatal imaging characteristics were summarized. Fetal and pregnant outcomes were recorded. Results Five cases who were diagnosed with CM at the third trimester were confirmed after labor or induced labor， 3 cases were misdiagnosed by prenatal ultrasound and 1 case was missed by prenatal MRI， respectively. Prenatal ultrasound characteristics mainly consisted of anal atresia （n = 5）， pelvic abdominal cyst （n = 4）， ambiguous genitalia （n = 3）， intestinal dilation （n = 2） and intestinal echo enhancement （n = 1）， respectively. Three cases were complicated with urinary hydrops. Prenatal MRI showed no high fetal signal in the rectum （n = 4）， abdominal cysts （n = 4）. Two pregnant women chose induced labor and 3 cases of live birth. Five CM fetuses were manifested with only 1 opening in the perineum， anal atresia and female appearance of external genitalia. Intraoperatively， 3 pelvic cavities converged into a common opening in the perineum in 2 cases. Conclusions Anal atresia and cystic mass in the midline of pelvic-abdominal cavity are the common prenatal imaging features of CM. The possibility of CM should be considered in the differential diagnosis in any fetus presenting with ambiguous genitalia， hydronephrosis and calcified meconium. MRI can more explicitly show the relationship among three pelvic cavities and the rectum.

【Key words】Prenatal diagnosis;Ultrasound;Magnetic resonance imaging;Cloacal malformation

一穴肛畸形（CM）是较严重的先天性肛门直肠畸形，属于泄殖腔畸形，临床很罕见，国外报道约占活产儿1/50 000。该病是指原始肛门位置处无肛门，尿道、阴道、直肠共同开口在会阴部的一个腔内，大、小便都由这个共同开口排出[1]。

由于CM临床表现多样且尿道、阴道、直肠彼此相关性在胎儿时期显示难度大，国外报道产前正确诊断率仅有6%[2-3]。出生后病情的严重程度取决于尿道、阴道及直肠共同通道的长度及合并畸形，胎儿出生后常需经多次手术矫治，给家庭及社会带来沉重的经济、生理及心理等负担。……