The long-term outcome of bilateral Cohen ureteric reimplantation under a common submucosal tunnel

Objective To analyse the results of bilateral Cohen reimplantation under a common submucosal tunnel, over an 18-year period. Patients and Methods We retrospectively examined 102 children (35 boys and 67 girls, median age 5.5 years, range 0.5-13.5) who underwent bilateral antireflux ureteric reimplantation from 1983 to 2000 with a modified Cohen technique, re-implanting both ureters under a common submucosal tunnel in the mid-trigonal area, to treat primary vesico-ureteric reflux (VUR, 99 patients) or obstructive megaureter (three). The mean (range) follow-up was 10.6 (2-18) years. Results The operation was successful in 198 of 204 (97%) ureters. One patient had vesico-ureteric stenosis in one ureter and was re-operated successfully. In two ureters in two different patients there was transient stasis after surgery caused by oedema within the tunnel, which gradually resolved. Two ureters in two other patients had reflux after surgery, which resolved spontaneously after 12 and 24 months, respectively. A 6-month old baby had anuria after surgery because of acute compression of both ureters within a narrow tunnel; this patient was re-operated, the tunnel widened and the obstruction resolved. None of 82 patients who had reached school age by the time of their last follow-up showed signs of voiding dysfunction. Conclusions The modified bilateral Cohen reimplantation with both ureters under a common submucosal tunnel offers very good long-term results in curing VUR or obstructive megaureter. Crossing one ureter upon the other within the tunnel does not predispose to long-term obstruction. From these results we recommend it as a reliable technique for surgically treating bilateral VUR or obstructive megaureter.