Service de Radiopediatrie, La Timone Children's Hospital, 264 rue saint-Pierre, Marseille 13385, France.
Pediatr Radiol. 2010 Jul;40(7):1215-21. doi: 10.1007/s00247-009-1497-x. Epub 2010 Jan 6.
It has been described that both the colon and distal ileum present with a physiological hypersignal on T1-weighted sequences during the second and third trimesters of pregnancy because of their protein-rich meconium content, it was unclear whether the normal characteristics that have been described on fetal MRI can be applied to gastrointestinal (GI) obstructions.
To analyse the localisation value of T1 hypersignal within dilated bowel loops in fetuses with gastrointestinal tract obstruction.
A retrospective 4-year multicentre study analysing cases of fetal GI obstruction in which MRI demonstrated T1 hypersignal content in the dilated loops. Data collected included gestational age (GA) at diagnosis, bowel appearance on US, CFTR gene mutations and amniotic levels of gastrointestinal enzymes. The suggested prenatal diagnosis was eventually compared to postnatal imaging and surgery.
Eleven patients were included. The median GA at US diagnosis was 23 weeks (range 13-32). In eight cases there was a single dilated loop, while several segments were affected in three. The median GA at MRI was 29 weeks (range 23-35). One case presented with cystic fibrosis mutations. Final prenatally suspected diagnoses were distal ileal atresia or colon in nine cases and proximal atresia in two. Postnatal findings were proximal jejunal atresia in nine cases and meconium ileus in two. In five cases the surgical findings demonstrated short bowel syndrome.
In cases of fetal occlusion, T1 hypersignal should not be considered as a sign of distal ileal or colonic occlusion. The obstruction may be proximal, implying a risk of small bowel syndrome, which requires adequate parental counselling.
已有研究表明，由于富含蛋白的胎粪内容物，妊娠 2 至 3 个月时胎儿的结肠和回肠远段在 T1 加权序列上呈现生理性高信号。但目前尚不清楚在胎儿 MRI 上描述的正常特征是否适用于胃肠道（GI）梗阻。
分析胎儿胃肠道梗阻时扩张肠袢 T1 高信号的定位价值。
这是一项回顾性的 4 年多中心研究，分析了 MRI 显示扩张肠袢 T1 高信号内容物的胎儿 GI 梗阻病例。收集的数据包括诊断时的胎龄（GA）、US 下的肠管表现、囊性纤维化跨膜传导调节因子（CFTR）基因突变和羊水中胃肠道酶的水平。产前诊断建议最终与产后影像学和手术进行比较。
共纳入 11 例患者。US 诊断时的中位 GA 为 23 周（范围 13-32 周）。8 例为单个扩张肠袢，3 例为多个肠段受累。MRI 诊断时的中位 GA 为 29 周（范围 23-35 周）。1 例存在囊性纤维化基因突变。产前可疑诊断为 9 例回肠远段或结肠闭锁，2 例为近端闭锁。产后发现 9 例为近端空肠闭锁，2 例为胎粪性肠梗阻。5 例手术结果显示为短肠综合征。
在胎儿梗阻的情况下，不应将 T1 高信号视为回肠远段或结肠闭锁的征象。梗阻可能是近端的，这意味着存在小肠综合征的风险，需要对父母进行充分的咨询。
