Clinical Significance of Perineal Descent in Pelvic Outlet Obstruction Diagnosed by using Defecography

PURPOSE: The aim of this study was to evaluate the clinical significance of perineal descent (PD) in pelvic outlet obstruction patients diagnosed by using defecography. METHODS: One hundred thirty-six patients with pelvic outlet obstruction (POO; median age 49 years) had more than one biofeedback session after defecography. Demographic finding, clinical bowel symptoms and anorectal physiological studies were compared for PD at rest and PD with dynamic changes. RESULTS: Age (r = 0.33; P < 0.001), rectocele diameter (r = 0.31; P < 0.01), symptoms of incontinence (P < 0.05) and number of vaginal deliveries (r = 0.46; P < 0.001) were correlated with increased fixed PD. However, the female gender (P < 0.005), rectal intussusceptions (P < 0.05), negative non-relaxing puborectalis syndrome (P < 0.00005) and rectocele (P < 0.0005) were correlated with increased dynamic PD. Duration of symptoms, number of bowel movements, history of pelvic surgery and difficult defecation were not related with PD. There was no significant correlation between fixed and dynamic PD and success of biofeedback therapy. CONCLUSION: Age, vaginal delivery and diameter of the rectocele are associated with increased fixed PD. Female gender, rectal intussusceptions and a rectocele are correlated with increased dynamic PD. Biofeedback is an effective option for POO regardless of severity of PD.

Prognostic Factors Associated with Poor Outcome of Biofeedback Therapy for Constipated Patients with Pelvic Outlet Obstruction

PURPOSE: The aim of this study was to identify the prognostic factors associated with poor outcome of biofeedback therapy. METHODS: One hundred thirty-seven (137) constipated patients with pelvic outlet obstruction (median age 49 years) had more than one biofeedback session after defecography. Follow-up data (mean follow-up: 14 months; range: 2~37 months) were obtained in 114 patients. Any differences in demographics, clinical symptoms, and parameters of an anorectal physiological study were evaluated between the success group and the failure group. RESULTS: At follow-up, 80 (70 percent) patients felt improvement in symptoms, but 34 (30 percent) patients did not. Pre-biofeedback presence of symptoms of difficult defecation predict poor outcome (88 vs. 69 percent for failure vs. success, P<0.05). The positive and the negative predictive values of difficult defecation for poor outcome were 35 percent and 86 percent, respectively. A negative mean pressure change on pre-biofeedback anal manometry was related to a poor outcome (65 vs. 26 percent for failure vs. success, P<0.001). The positive and the negative predictive values of negative mean pressure change for poor outcome were 51 percent and 83 percent, respectively. A negative electrical current change on pre-biofeedback anal electromyography was related to a poor outcome (23 vs. 9 percent for failure vs. success, P<0.05). The positive and the negative predictive values of negative electrical-current change for poor outcome were 53 percent and 74 percent, respectively. CONCLUSIONS: Difficult defecation, negative mean pressure change in pre-biofeedback anal manometry, and negative electrical current change in pre-biofeedback anal electromyography were predictors associated with poor outcome of biofeedback therapy for constipated patients with pelvic outlet obstruction.

Surgical Management of Obstructed Defecation

There are three groups of patients with constipating symptoms; those with obstructed defecation, slow transit constipation, or both. The treatment of obstructed defecation (pelvic outlet obstruction) is often challenging because the underlying disorders are diverse with a wide range of and clinical symptoms. The underlying anatomical and pathophysiological changes in patients with obstructed defecation are complex and often poorly understood. As a consequence, many medical, surgical, and behavioral approaches have been described, with no single panacea. For successful outcomes, preoperative physiologic testing is mandatory to differentiate between obstructed defecation caused by pelvic outlet obstruction and slow transit constipation. Obstructed defecatory disorders can distress patients both socially and psychologically and greatly impair their quality of life. For the great majority of patients, dietary adjustment with an increased fiber and liquid supplement can resolve the symptoms. The surgical approach depends upon the etiology, severity of symptoms, and operative risks. In a small group of patients with a rectocele or a third degree sigmoidocele, surgical intervention yields a high success rate. Division or resection of the puborectalis muscle is not recommended. In patients with a mixed pattern of slow transit colon and pelvic outlet obstruction, surgical intervention alone is often not successful; these patients can experience better outcomes by conservative treatment of pelvic outlet obstruction, followed by a colectomy. Stapled transanal rectal resection has recently become a recommended surgical procedure for obstructed defecation syndrome. One problem when using a transanal stapling device for rectal surgery is the potential damage to the structures located in front of the anterior rectal wall. The laparoscopic approach can shorten the hospital stay with good outcomes and is well tolerated in elderly patients with rectal prolapse. Despite the progress in modern surgery, the choice of the surgical procedure of pelvic outlet obstruction is still controversial. Preoperative counseling of all patients undergoing surgery is of extreme importance, in particular to explain the evolving nature of pelvic floor dysfunction and the possible need for further reconstructive surgery. To identify patients who will benefit from surgery for obstructed defecation, a careful selection of candidate patients remains the crucial issue in the diagnostic assessment. Surgical intervention should be limited only to the patients with identifiable, surgically correctable causes of outlet obstruction. This review gives an overview of surgical treatment options in patients with obstructed defecation.

Physiologic Characteristics and its Clinical Significances in the Patients with Pelvic Outlet Obstruction

Current study was designed to assess the functional etiology of patients with pelvic outlet obstruction. Moreover, physiologic characteristics and theirs clinical significances were evaluated in the patients with ramified diagnosis. METHODS: 172 patients with pelvic outlet obstruction were performed 328 numbers of physiologic studies. These included cinedefecography (n=172), anal manometry (n=87), colonic transit time study (n=38), and anal EMG/PNTML (n=31). On the basis of physiologic findings, patient groups were categorized as rectocele (group I), nonrelaxing puborectalis syndrome (group II), anal dyschezia (group III), and rectoanal intussusception (group IV). The physiologic findings were compared between subgroup patients. RESULTS: Incidence of categorized patients was 51.7% (group I, n=89), 22.7% (group II, n=39), 12.2% (group III, n=21), and 8.7% (group IV, n=15), respectively. The mean age of patients with group III were lower (p<0.05) than that of overall patients. The incidence of female patients was higher in group I and the incidence of male patients was higher in group II (p<0.0001). In cinedefecography, patients with group II showed smaller anorectal angle at strain (p<0.001), at dynamic change between rest and strain (p=0.002). In anal manometry, patients with group III showed higher mean resting pressures (p=0.001), higher maximum resting pressures (p<0.001), higher mean squeeze pressures, and higher maximal voluntary contraction (p=0.003) than those of patients with other group. In neurologic study, mean value of PNTML was 2.32 +/- 0.34 (range, 1.60~3.66) msec in overall patients. The size of rectocele was increased in proportion to patient's age (r=0.229, p<0.05), number of delivery (r=0.393, p=0.001), and degree of perineal descent (r=0.231, p<0.05). The degree of perineal descent was increased in proportion to patient's age (r=0.249, p<0.05). CONCLUSIONS: Present series provided the diagnostic ramification of pelvic outlet obstruction by using the anorectal physiologic investigations. In addition to the function of puborectalis muscle, evacuation dynamics of anorectum should be emphasized. These findings could provide the fundamental information for guideline of future therapy in the patients with obstructed defecation.