Investigate perineal body size and anal axis before and after posterior colporrhaphy using validated 2D perineal Pelvic Floor Ultrasound (pPFUS) measurements. In addition investigate whether bowel symptoms in patients with severe posterior compartment prolapse improve after surgery.

Ethical Committee and Health Research Authority (HRA) approval was granted for this study (IRAS 17/LO/1398). The perineal body area was measured as previously described (1). In addition the anal axis was assessed as the anal canal to pubis angle (2). Qualitative assessment of bowel symptoms was performed using the Birmingham bowel and bladder questionnaire (3) before and after surgery. Data were analysed using Minitab v19 (Minitab LLC., USA).

Fifty-eight patients underwent a posterior repair for whom there were pre and post-operative perineal body area measurements for 57 patients and for 44 patients anal canal angle measurements. 
The median (IQR) perineal body area increased from 1.5 (0.6 to 2.7)cm2 pre-operatively to 3.3 (2.2 to 4.6)cm2 post-operatively, Wilcoxon Signed Rank (WSR) of paired differences, p<0.001, n=57. Pre-operatively, the median (IQR) anal canal to pubis angle (anal axis) was 119 (108 to 131)° and post-operatively the anal axis angle was 112 degrees (101 to 121 degrees) WSR of paired differences p=0.008, n=44). There was a significant reduction in the need to strain (Q7, WSR p=0.03, n=54); time spent in the toilet (Q8, WSR, p<0.001); feeling of incomplete evacuation (Q9, p<0.001); need to digitate for evacuation (Q10, p=0.01), being unable to initiate defaecation (Q12, p=0.01), dyschezia (Q13, p=0.014) and in faecal urgency (Q4, p=0.02). There was no significant change for faecal incontinence (Q5, p=0.38).

There was a clear increase in perineal body area measured from ultrasound scanning. The pelvic floor anatomy as visualised on pPFUS significantly changed. Overall generally surgical reduction of prolapse improved functional bowel symptoms. 
 
 
Post-operative dimensions of the perineal body and anal axis approach what would be expected in control patients (1,2). The perineal body area in healthy volunteers was a mean of 2.8 (2.3-3.3) cm2 (1). The anal canal to pubis angle (anal axis) in healthy volunteers is 98.2 degrees (SD 15.9).
 
Rectocoele appears to cause trapping of stools that can require digital manipulation, difficulty to initiate and/or complete a bowel motion. In our study these symptoms of obstructive defaecation often improved with posterior colporrhaphy. This information may be useful for patients in pre-operative counselling.

Native tissue posterior colporrhaphy normalises pelvic floor perineal body and anal axis anatomy, which results in improvement of functional symptoms of obstructive defaecation.

Asfour, Victoria; Digesu, Giuseppe Alessandro; Fernando, Ruwan; u. a. (2019): „Ultrasound imaging of the perineal body: a useful clinical tool.“. In: International Urogynecology Journal. DOI: 10.1007/s00192-019-04166-7.
Asfour, Victoria; Gibbs, Kayleigh; Wertheim, David; u. a. (2021): „Anal canal to pubis angle: a novel clinical ultrasound technique for the assessment of the anorectal region.“. In: International Urogynecology Journal. DOI: 10.1007/s00192-021-04855-2.
Hiller L et al.  Development and validation of a questionnaire for the assessment of bowel and lower urinary tract symptoms in women. BJOG. 2002; 109: 413-23. doi: 10.1111/j.1471-0528.2002.01147.x.

Continence 7S1 (2023) 100894
DOI: 10.1016/j.cont.2023.100894