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

Abstract 

Objective

The aim of this prospective study was to evaluate whether urinary flow improves with time after tubularized incised plate (TIP) repair.

Patients and method

Between 1999 and 2003, primary TIP was performed in 126 boys. In patients old enough (48 boys, mean age at surgery 46 months, range 18–103), uroflowmetry was performed 1 year and 7 (median, range 3–10) years post surgery. Miskolc nomograms were used to compare results from the two follow ups (Q_max in relation to voided volume and age).

Results

Eleven boys had symptoms of obstruction resulting in intervention. For the other 37 boys, the mean Q_max was 13.6 ± 5.6 ml/s 1 year postoperatively (mean voided volume 107 ± 43 ml) and 49% had flows below the 5th percentile. Seven years postoperatively the mean Q_max was 19.0 ± 8.1 ml/s (mean voided volume 235 ± 112 ml) and 32% had flows below the 5th percentile. In the group with flows below the 5th percentile at 1 year, all improved and 28% improved to above the 25th percentile. Proximal hypospadias was more often associated with obstructive flow than distal (75%/75% compared to 43%/21% 1/7 years postoperatively).

Conclusion

We found spontaneous improvement (P = 0.00022) 7 years after TIP repair, although many boys still had a Q_max in the low normal or obstructive range.

Keywords: Hypospadias, TIP, Obstruction, Flow rate