POSTOPERATIVE MRI OF ANORECTAL MALFORMATION

Twenty-five patients who had pull-through rectum (PTR) surgery, some o f whom suffered from fecal incontinence, soiling or constipation were studied by magnetic resonance imaging (MRI) postoperatively. MRI demon strated 14 patients with proper placement of the PTR between the pubor ectal muscle and external sphincter muscle; four patients with imprope r placement of the PTR outside the puborectal muscle and external sphi ncter muscle(one with excess perirectal fat); one patient with disrupt ion of the puborectal muscle and external sphincter muscle; three with hypoplasia of the puborectal muscle and external sphincter muscle; th ree with asymmetric placement of PTR in the levator ani (one with exce ss perirectal fat). MRI also depicted seven patients with spine anomal ies; five with tethered cord; and 10 with genitourinary tract anomalie s. The patients with correct location of PTR all had good fecal contin ence except three patients (two with soiling and one with constipation ) who had tethered cord and ganglion cell dysfunction at the PTR. The patients with improper placement of PTR or poorly developed pelvic mus cles all had fecal incontinence. Our study emphasizes that MRI can dep ict the causes of postoperative incontinence, detect anomalies and hel p to plan further surgery.