New trends in the surgical treatment of outlet obstruction: clinical and functional results of two novel transanal stapled techniques from a randomised controlled trial

Background and aims. A randomised trial was undertaken to compare the clinical and functional results of two novel transanal stapled techniques in patients with outlet obstruction syndrome. Materials and methods. Ninety-six females with outlet obstruction were treated with medical therapy and biofeedback for 2 months; 67 non-responders were evaluated by the Constipation Scoring and Continence Grading Systems, clinical examination, endoscopy, dynamic defecography, anorectal manometry, transanal ultrasound and anal EMG, and 50 of them, all affected with descending perineum, intussusception and rectocele, were randomly assigned to two groups and operated on: 25 patients (mean age 53.2+/-15.3 years) underwent a single Stapled Trans-Anal Prolapsectomy, associated with Perineal Levatorplasty (STAPL Group), and the other 25 (mean 54.6+/-14.2 years) underwent a double Stapled Trans-Anal Rectal Resection (STARR Group). Patients were followed-up for a mean period of 23.4+/-5.1 months in STAPL Group and 22.3+/-4.8 in STARR Group. Results. STARR Group showed a significantly (p <0.0001) lower pattern of postoperative pain and a greater decrease (P =0.0117) of the rectal sensitivity threshold volume; otherwise, no differences were found in operative time, hospital stay, or time of inability to work. Complications included delayed healing of the perineal wound (ten), dyspareunia (five), urinary retention (two) and stenosis (one) in STAPL Group, and urge to defecate (four), transitory incontinence to flatus (two), urinary retention (two), bleeding (one) and stenosis (one) in STARR Group. All constipation symptoms significantly improved without worsening of anal continence and with excellent/good outcome at 20 months in 76 and 88% of patients of STAPL Group and STARR Group, respectively. Seven patients of STAPL Group had a little residual rectocele, while both intussusception and rectocele were corrected in all patients of STARR Group. Neither operation modified anal pressures or caused lesions of anal sphincters. Conclusions. Both techniques are safe and effective in the treatment of outlet obstruction; nevertheless, the double Stapled Trans-Anal Rectal Resection seems to be preferable due to less pain, absence of dyspareunia, reduced rectal sensitivity threshold volume and absence of residual rectocele at defecography.