Intestinal malrotation is a congenital anomaly resulting from an abnormal rotation and fixation of the midgut during embryological development. While typically diagnosed in neonates and infants presenting with signs of bowel obstruction or volvulus, malrotation can occasionally be identified incidentally in adults during imaging for unrelated complaints. This anomaly often results in an abnormal location of the duodenojejunal (DJ) junction, inversion of the SMA-SMV relationship, and ectopic cecal position. Although it may remain asymptomatic, nonrotation predisposes patients to life-threatening complications such as midgut volvulus.
A patient underwent cross-sectional imaging for evaluation of nonspecific abdominal symptoms. Contrast-enhanced CT imaging revealed the following key findings:
There were no signs of bowel obstruction or volvulus on imaging at the time of study
Intestinal rotation anomalies encompass a spectrum of developmental errors that occur during the embryological rotation and fixation of the midgut. The normal 270° counterclockwise rotation brings the small bowel to the central and left abdomen, and the colon to the right side, with the DJ junction placed left of the midline and posterior to the superior mesenteric vessels.
Imaging plays a critical role in the diagnosis. CT findings such as abnormal DJ junction position, absent retro-mesenteric D3, reversed SMA-SMV relationship, and ectopic cecal location are highly suggestive of malrotation. In uncertain cases, an upper GI contrast study can provide additional functional and anatomical details.
These anatomical aberrations predisposes to midgut volvulus, bowel obstruction, internal hernias, chronic abdominal pain, and bowel ischemia due to abnormal intestinal positioning and narrow mesenteric attachment.
While most symptomatic cases are identified in infancy, adult presentations are not uncommon, particularly in cases of intermittent symptoms or complications like volvulus. In asymptomatic individuals, incidental detection may warrant a discussion about potential risks.
This case illustrates the classic imaging features of intestinal Malrotation in an adult. Recognition of this condition is crucial, even in asymptomatic individuals, due to the potential for life-threatening complications such as volvulus. A high index of suspicion and appropriate imaging interpretation are essential for timely diagnosis and management.
Dr. Ameer Hussain A Consultant Radiologist Kauvery Hospital Chennai
Dr. Manish Yadav DNB Radiology Resident Kauvery Hospital Chennai
