Electrical stimulated graciloplasty in the male goat: an animal model for urethral pressure measurement.

Abstract

The feasibility of dynamic urinary graciloplasty as a treatment for incontinence is currently investigated. Therefore an animal model is developed to improve the technique of dynamic urinary graciloplasty. This article is a report of the urethral pressure measurements in the male goat. This study compares the graciloplasty around the bulbous urethra with the graciloplasty around the bladderneck. The male goat as an animal model of urethral pressure measurements is discussed. Under anaesthesia in ten male goats the penile shaft outside the pelvis was dissected. Urethral pressure profilometry was performed. The bulbous urethra was dissected and a split sling graciloplasty was performed around the bulbous urethra. The contralateral gracilis was used for bladderneck graciloplasty. Urethral pressure profilometry was done without and with electrical muscle stimulation. The highest native urethral pressure was 136 cm water at the pelvic outrance. Without stimulation the bladderneck graciloplasty pressure was 97 cm water. The bulbous urethra graciloplasty pressure was 122 cm water. These pressures were not significantly different from the pelvic outrance pressure. With stimulation the highest bladderneck and bulbous urethra graciloplasty pressures were 183 cm water and 294 cm water respectively. The stimulated bulbous urethra graciloplasty pressure was significantly higher than the highest native urethral pressure. In conclusion, the male goat is a suitable animal model for urethral pressure measurement. The highest native urethral pressure is located at the pelvic outrance. A non-stimulated graciloplasty acts like a sling with regard to generated urethral pressure. With stimulation sphincterlike activity of the graciloplasty can be observed. In male goats the graciloplasty around the bulbous urethra is superior to the bladderneck graciloplasty.