How can laparoscopy help evaluate patients with suspected rotational anomalies?

Again, the subject of rotational anomalies and equivocal UGI findings came up. The next day, this paper by Hsiao et al out of Sick Kids in Tornoto was in JPS. Here the authors discuss the utility of diagnostic laparoscopy as a tool to help corroborate UGI findings, or as a tie breaker for equivocal UGI studies.

The article was based on two premises. The first is what defines malrotation vs. non-rotation. Malrotation, here, was defines as the DJJ and the cecum near the midline, and the base of the mesentery less than 50% of the diameter of the abdomen. Non-rotation was defined as DJJ to the right of midline, ceceum in the lower left or central abdomen, small bowel on the left side, colon on the right, and base of mesentery is longer than 50% of the diameter of the abdomen. The other premise is that the small bowel is not at risk of midgut volvulus when the base of the mesentery is longer than 50% of the diameter of the abdomen (as in normal and non-rotation), and a Ladd's procedure is not necessary.

Very few people would argue that an infant with bilious emesis who is found to have an abnormal UGI needs exploration. The issue becomes more controversial when abnormal UGI studies are found in children with no symptoms or chronic and/or non-specific symptoms. This is the group of patients this paper addressed.

The UGI results studies included findings consistent with malrotation, malrotation with volvulus, non-rotation, or equivocal findings. Of the patients with UGI findings consistent with malrotation, ~60% had malrotation confirmed by laparoscopy (with or without volvulus), and the rest had either non-rotation (30%) or were normal (10%) (both conditions the authors believe do not need surgical correction). When UGI's showed non-rotation, laparoscopic evaluation was consistent with the diagnosis in all patients. Finally, of the patients with an equivocal UGI, a third had malrotation with/without volvulus, and the rest were found to be either non-rotated (48%) or normal (21%) on laparoscopic evaluation.

So if we accept that a mesenteric base longer than 50% of the diameter of the abdomen constitutes a stable mesenteric base not prone to volvulus (a finding confirmed by laparoscopy), laparoscopy can be an important tool that can help us manage this perplexing population of patients with no/vague symptoms and inconclusive UGI studies.


Reference:
Hsiaoo M, Langer JC. Value of laparoscopy in children with a suspected rotation abnormality on imaging. Journal of Pediatric Surgery (2011) 46, 1347-1352