Prenatal diagnosis of intestinal nonrotation using magnetic resonance imaging: Is it possible?

Twenty years' experience of midgut malrotation and volvulus in a tertiary center in northern Taiwan: A retrospective study

BACKGROUND

Early diagnosis and surgical intervention for midgut malrotation with bowel obstruction are crucial. We aimed to identify risk factors for adverse outcomes in infants with midgut malrotation and to develop a prediction model.

METHODS

We reviewed the operation records of infants surgically diagnosed with midgut malrotation at Chang Gung Children's Medical Center between January 2000 and December 2020. Patients were classified into the poor-outcome group (PO) if they underwent bowel resection or experienced mortality; all others were categorized as the favorable-outcome group (FO). Data on demographics, initial presentations, laboratory results, radiographic or sonographic findings, maternal conditions, and outcomes were collected and analyzed. Fisher's exact test, the independent sample t-test, and the Mann-Whitney test were utilized for comparative analysis when suitable.

RESULTS

The study included 103 infants. Eleven were in the PO group, and 92 were in the FO group. Initial presentations such as respiratory distress, poor activity, and shock status were notably more prevalent in the PO group. The INR, hemoglobin, HCO3, base excess, and aspartate transaminase values showed significant variation between the two groups. Multivariate analysis identified that lower hemoglobin (OR 0.677, p = 0.043) and higher AST (OR 1.036, p = 0.044) were independent predictors of adverse outcomes. An AST/Hb ratio of <3.78 demonstrated a high negative predictive value (98.6%) for an adverse outcome in midgut malrotation.

CONCLUSIONS

Prompt diagnosis and surgical treatment of midgut malrotation are vital to prevent bowel resection or mortality. The independent predicting factors for poor outcomes include low hemoglobin and elevated AST levels.

A case of isolated malrotation without midgut volvulus diagnosed prenatally and treated by laparoscopic surgery

BACKGROUND

Malrotation is a congenital condition that predisposes individuals to midgut volvulus, which can result in significant bowel resection. While most cases of malrotation are diagnosed by the age of 1 year, typically presenting with symptoms related to volvulus or bowel obstruction, some cases remain asymptomatic. In children with visceral malposition, gastroschisis, omphalocele, or diaphragmatic hernia, malrotation may be suspected before symptoms manifest. However, isolated malrotation without midgut volvulus diagnosed prenatally is rare. We herein present a case of isolated malrotation without midgut volvulus that was prenatally diagnosed and successfully treated with laparoscopic surgery.

CASE PRESENTATION

A 30-year-old woman (gravida 3, para 1) underwent routine obstetric ultrasound, which revealed increased blood flow in the lower uterine segment and abnormal placental attachment. To rule out placenta percreta, magnetic resonance imaging was performed at 34 weeks of gestation. Incidentally, abnormal fetal intestinal arrangement was noted, with the colon localized in the left hemi-abdomen and the small intestine distributed in the right hemi-abdomen, raising suspicion of malrotation. Postnatal contrast studies confirmed the diagnosis of malrotation without midgut volvulus. Given the risk of midgut volvulus, a laparoscopic Ladd's procedure was performed on day 6 of life. The postoperative course was uneventful, and the patient was still symptom-free 1 year postoperatively.

CONCLUSIONS

This case illustrates that malrotation can be prenatally diagnosed using fetal magnetic resonance imaging. Considering the risk of midgut volvulus, prophylactic Ladd's procedure should be performed in neonatal period. In cases where malrotation is not complicated by midgut volvulus, a laparoscopic Ladd procedure can be safely performed in neonates.

Contribution of fetal magnetic resonance imaging in fetuses with congenital heart disease

BACKGROUND

Increasing evidence supports an association among congenital heart disease (CHD), structural brain lesions on neuroimaging, and increased risk of neurodevelopmental delay and other structural anomalies. Fetal MRI has been found to be effective in demonstrating fetal structural and developmental abnormalities.

OBJECTIVE

To determine the contribution of fetal MRI to identifying cardiovascular and non-cardiovascular anomalies in fetuses with CHD compared to prenatal US and fetal echocardiography.

MATERIALS AND METHODS

We performed a retrospective study of fetuses with CHD identified by fetal echocardiography. Exams were performed on 1.5-tesla (T) or 3-T magnets using a balanced turbo field echo sequence triggered by an external electrocardiogram simulator with a fixed heart rate of 140 beats per minute (bpm). Fetal echocardiography was performed by pediatric cardiologists and detailed obstetrical US by maternal-fetal medicine specialists prior to referral to MRI. We compared the sensitivity of fetal MRI and fetal echocardiography for the diagnosis of cardiovascular anomalies, as well as the sensitivity of fetal MRI and referral US for the diagnosis of non-cardiac anomalies. We performed statistical analysis using the McNemar test.

RESULTS

We identified 121 anomalies in 31 fetuses. Of these, 73 (60.3%) were cardiovascular and 48 (39.7%) involved other organ systems. Fetal echocardiography was more sensitive for diagnosing cardiovascular anomalies compared to fetal MRI, but the difference was not statistically significant (85.9%, 95% confidence interval [CI] 77.8-94.0% vs. 77.5%, 95% CI 67.7-87.2%, respectively; McNemar test 2.29; P=0.13). The sensitivity of fetal MRI was higher for diagnosing extracardiac anomalies when compared to referral US (84.1%, 95% CI 73.3-94.9% vs. 31.8%, 95% CI 18.1-45.6%, respectively; McNemar test 12.9; P<0.001). The additional information provided by fetal MRI changed prognosis, counseling or management for 10/31 fetuses (32.2%), all in the group of 19 fetuses with anomalies in other organs and systems besides CHD.

CONCLUSION

Fetal MRI performed in a population of fetuses with CHD provided additional information that altered prognosis, counseling or management in approximately one-third of the fetuses, mainly by identifying previously unknown anomalies in other organs and systems.