The Yang–Monti ileovesicostomy: a problematic channel?

Objective To compare the differences in the quality of Mitrofanoff channels created using appendix and re‐tubularized small bowel (the Yang–Monti ileovesicostomy). Patients and methods The case‐notes were reviewed retrospectively for all patients who underwent a Mitrofanoff procedure using either appendix or small bowel, over a 5‐year period from June 1994 to July 1999. Results In all, 92 patients underwent 94 Mitrofanoff procedures; the appendix was used in 69 and small bowel in 25. The underlying diagnoses were exstrophy‐epispadias complex (38), neuropathic bladder (21), anorectal malformations and cloacal anomalies (15), posterior urethral valves (nine) and miscellaneous (nine). The mean (range) age at operation was 9.2 (1.1–18.3) years. The mean (range) follow‐up for the appendix group was 37 (6.7–65) months and for the Monti group 25 (6–66) months. Catheterization problems occurred in 18 (27%) patients from the appendix group; two needed an adjustment of technique, six dilatation and 10 revision. Stomal stenosis occurred in 10 (15%) patients, bladder level stenosis in four (6%) and conduit necrosis in two. Catheterization problems were reported in 15 (60%) patients from the Monti group; five needed revision, three dilatation and seven are being managed conservatively. The incidences of stomal stenosis (four, 16%) and bladder level stenosis (two, 8%) were comparable with the appendix group. In addition, two patients had distal channel (sub‐stomal) stenosis and two had mid‐channel stenosis. The problem unique to the Yang–Monti channel was a pouch‐like dilatation in seven patients (28%), all of whom presented with catheterization problems; five are being managed conservatively and two have needed pouch resection. Stomal prolapse occurred in five (7%) patients in the appendix group, but in none of the Monti group. Conclusions The appendix is the conduit of choice for a Mitrofanoff procedure. Re‐tubularized small bowel conduits have a considerably higher incidence of catheterization problems. Anatomical factors may contribute to the unique incidence of pouch formation.