High pressure zone (cm) Resting pressure (mmHg) Maximum squeezing pressure (mmHg) Fatigue rate (mmHg/ min) Fatigue rate index (min) Sphincter asymmetry index (%) Rectal sensitivity threshold (ml) Rectal capacity (ml) Before 3 63.7 129.7 -46.6 3 22.4 76 158 After 2.7 64.9 116.9 -56.6 2.1 14.4 72 156 Before 3 69 130 -34.9 1.49 20 70 150 After 3 66 118 -27.4 1.62 14.7 60 150 *Student’s t-test and paired-sample Wilcoxon test. There was no change in quality of life in relation to anal continence when the pre- and postoperative results of patients who underwent a radical perineal prostatectomy were compared. Therefore, the Anal Incontinence Index9 and Fecal Incontinence Quality of Life questionnaire18 enhanced the sensitivity of our evaluation and provide a more accurate evaluation of anal incontinence in the studied Before After Before After Before After 1 22.5 41.4 44.3 11.2 9.1 24.7 48 0.8 16.7 40.4 49.8 5.4 4.5 35.2 56 1 28 36 -161 -16 9 30 80 1 34 23 -163 -12 7 20 80 5 100 198 -28 -54 46 120 140 4 99 190 -94 -21 18 160 140 p-value* 0.398 0.763 0.165 0.754 0.438 0.003 0.539 0.836 patients because both instruments have been validated and are recognized worldwide. The anal canal is a naturally asymmetrical structure, especially considering the force vectors involved.27-29 These force vectors are related to the distribution of the anal canal muscles and other structures, including the submucosa hemorrhoidal plexus. 29,30,31 However, a high sphincter CLINICS 2011;66(12):2007-2012 Perineal prostatectomy and anal incontinence Guilger NR et al. Table 1 - Anorectal manometry parameters in patients before and after perineal prostatectomy. Mean Median Standard Deviation Minimum Maximum Figure 4 - Sphincter Asymmetry Index scores before and after surgery in 23 patients who underwent perineal prostatectomy. 2011