The Kropp‐onlay procedure (Pippi Salle procedure): a simplification of the technique of urethral lengthening. Preliminary Results in eight patients

Objective To lengthen the urethra to increase bladder outlet resistance in adolescent girls with a neuro-genic bladder. Patients and methods During a 2-year period (1992–94), eight girls (mean age 13.5 years, range 9–19) underwent a Kropp-onlay urethral lengthening associated, for six of them, with a bladder augmentation. Seven of the eight patients patients were spina biflda and confined to a wheelchair. One patient had had a previous transverse myelitis. A Benchekroun hydraulic valve (in three cases) and a Malone procedure (in two cases) were performed at the same stage. The technique of Kropp-onlay urethral lengthening, which creates a flap valve mechanism which leaks when the bladder is too full, is described and illustrated. Results Seven of eight patients were dry during the day and four were occasionally damp during the second part of the night. One could not be dry for more than 2 h during the day but had a very hyperactive detrusor. She developed two bladder stones which required an open vesicotomy. One developed a urethral fistula requiring a second Kropp-onlay procedure and became dry afterwards. Two patients, who did not undergo a bladder augmentation, needed oxybutinin therapy to obtain a satisfactory result. Post-operative urodynamic measurements are discussed. Conclusion The Kropp-onlay urethral lengthening is easier to perform than the original Kropp procedure. The preliminary Resultsare similar to those of alternative techniques (e.g. urethral suspension) but long-term reliability of this technique remains unknown.