Hypospadias repair with tubularized incised plate: Does the obstructive flow pattern resolve spontaneously?

Purpose Hypospadias repair with tubularized incised plate urethroplasty (TIP) produces good cosmesis but is reported to result in obstructed urinary flow postoperatively. The aim of this study was to investigate if urinary flow improves with time. Material and Methods Between 1999 and 2003, primary TIP was performed in 126 boys. In boys old enough uroflowmetry was performed 1 year and 6 years postoperatively (38 boys). For symptoms and cosmesis a questionnaire was used. The Miskolc normograms (peak flow 2 > voided volume = normal flow) were used to calculate and evaluate normal peak flow. Results 34/38 boys had improved their urinary peak flow between 1 year and 6 year postoperatively. Ten boys had obstruction that led to intervention early. The 28 boys with no intervention had a 36% (Md) increase in peak flow spontaneously. At both one and 6 years postop 68% (19/28 boys) had normal flow. Of the boys with no intervention 86% (24/28 boys) improved their urinary flow spontaneously, but considering the expected increase in bladder capacity with age, there was no increase in number of boys with normal flows. No patients stated obstructive symptoms and they were all satisfied with cosmesis. Conclusions There is spontaneously an improvement in peak urinary flow after TIP repair, but it is most likely secondary to an increased bladder capacity with age. There are still many with an obstructive flow after 6 years, even if patients do not state obstructive symptoms.