Fetal Superior Mesenteric Artery Peak Systolic Velocity as a Marker of Prenatal Bowel Inflammation in Gastroschisis: A Case-Control Study.

OBJECTIVE

This study aimed to evaluate whether peak systolic velocity (PSV) in the fetal extra-abdominal superior mesenteric artery (SMA) is a useful prenatal marker of bowel inflammation in gastroschisis (GS), which manifests postnatally as bowel matting.

METHODS

This case-control study included 30 fetuses with gastroschisis who underwent standardized bowel assessment and Doppler measurement of the extra-abdominal SMA-PSV. Postnatal bowel status was classified as normal or inflamed. The primary analysis examined the association between fetal SMA-PSV and bowel inflammation, using linear models and generalized estimating equations for repeated measurements.

RESULTS

Among 30 fetuses, bowel matting was identified postnatally in 10 cases (33.3%). These neonates had significantly lower birthweight percentiles (5.5 vs. 50.5; p = 0.002) and more frequent ultrasound inflammatory signs such as bowel wall oedema (80% vs. 15%; p = 0.002), bowel wall stiffness (50% vs. 5%; p = 0.004), and corrugation wall (60% vs. 5%; p = 0.004). PSV was strongly correlated with bowel wall thickness (r = 0.81) and significantly higher in fetuses with postnatally diagnosed bowel matting (p < 0.001). GEE models showed that higher prenatal PSV independently predicted the later occurrence of bowel matting. Incorporating the time × bowel matting interaction significantly improved model fit (adjusted R2 = 0.460).

CONCLUSIONS

Fetal SMA-PSV is significantly associated with prenatal/ultrasound and postnatal signs of bowel inflammation in gastroschisis, such as bowel wall thickening and bowel matting. This association appears independent of the simple/complex GS surgical classification, suggesting PSV as a functional marker of intestinal compromise. Although technically demanding, SMA-PSV assessment may aid prenatal evaluation and perinatal planning, particularly in detecting evolving intestinal inflammatory cases.