OBJECTIVES: To study the effect of radical retropubic prostatectomy on urethral microcirculatory blood perfusion and urinary continence. Urinary stress incontinence after radical prostatectomy depends mainly on intrinsic distal sphincter integrity. METHODS: Urethral laser Doppler flowmetry was performed in 37 patients before and in 23 patients after (mean 15 months, range 2 to 23) radical prostatectomy for clinically localized prostate cancer. An endoscopic laser Doppler flow probe with a diameter of 1.8 mm was introduced through the working channel of a cystoscope and gently applied to the urethral mucosa at an intravesical pressure of 30 cm H(2)O. Blood flow was expressed simultaneously as a digital reading on the flowmeter (milliliters blood per minute per 100 gram tissue). The mean arterial blood pressure was monitored noninvasively. The Mann-Whitney U test was used for statistical analysis. RESULTS: Membranous urethral blood flow significantly decreased after radical prostatectomy from 18.8 +/- 7.9 mL/min per 100 gram tissue to 11.9 +/- 7.7 mL/min per 100 gram tissue (P = 0.04). However, the difference in the blood flow did not statistically differentiate continent patients from patients with urinary stress incontinence (P = 0.47). No correlation between urethral microcirculation and mean arterial blood pressure could be detected. CONCLUSIONS: Retropubic radical prostatectomy decreases membranous urethral microcirculation. However, this loss of vascularization does not have a major effect on distal sphincter function and continence after radical prostatectomy.
OBJECTIVES: To study the effect of radical retropubic prostatectomy on urethral microcirculatory blood perfusion and urinary continence. Urinary stress incontinence after radical prostatectomy depends mainly on intrinsic distal sphincter integrity. METHODS: Urethral laser Doppler flowmetry was performed in 37 patients before and in 23 patients after (mean 15 months, range 2 to 23) radical prostatectomy for clinically localized prostate cancer. An endoscopic laser Doppler flow probe with a diameter of 1.8 mm was introduced through the working channel of a cystoscope and gently applied to the urethral mucosa at an intravesical pressure of 30 cm H(2)O. Blood flow was expressed simultaneously as a digital reading on the flowmeter (milliliters blood per minute per 100 gram tissue). The mean arterial blood pressure was monitored noninvasively. The Mann-Whitney U test was used for statistical analysis. RESULTS: Membranous urethral blood flow significantly decreased after radical prostatectomy from 18.8 +/- 7.9 mL/min per 100 gram tissue to 11.9 +/- 7.7 mL/min per 100 gram tissue (P = 0.04). However, the difference in the blood flow did not statistically differentiate continent patients from patients with urinary stress incontinence (P = 0.47). No correlation between urethral microcirculation and mean arterial blood pressure could be detected. CONCLUSIONS: Retropubic radical prostatectomy decreases membranous urethral microcirculation. However, this loss of vascularization does not have a major effect on distal sphincter function and continence after radical prostatectomy.