Neurovascular antropylorus perineal transposition using inferior rectal nerve anastomosis for total anorectal reconstruction: preliminary report in humans

Abstract

Technical feasibility of inferior rectal nerve anastomosis to the anterior vagus branch of the perineally transposed antropyloric valve for total anorectal reconstruction has been previously demonstrated in cadavers. To the best of our knowledge, the present study is the first report of using this procedure in humans. Eight patients [mean age 35.5years (range 15-55years); (male/female=7:1)] underwent the procedure. The antropyloric valve with its anterior vagus branch was mobilized based on the left gastroepiploic arterial pedicle. The antral end was anastomosed to the distal colon. The anterior vagus nerve was anastomosed by epineural technique to the inferior rectal nerve in the perineum. A diverting proximal colostomy was maintained for 6months. Anatomical integrity of the graft (on magnetic resonance imaging scans), its arterial pedicle (on computed tomography angiogram) and neural continuity (on ultrasound and pyloric electromyography) were assessed. Functional assessment was performed using barium retention studies, endoscopy, manometry and fecal incontinence scores. Tension-free end-to-end anastomosis of the anterior vagus nerve to the right (n=7) and left (n=1) inferior rectal nerve was achieved. An intact left gastroepiploic pedicle, a healthy graft and neural continuity were visualized on perineal ultrasound. Electromyographic activity was noticed on neural stimulation. Endoscopy and barium studies showed voluntary antral contraction and contrast retention, respectively, in all patients. The mean resting and squeeze pressures were 26.25mmHg (range 16-62mmHg) and 50.25mmHg (range 16-113mmHg), respectively. St. Mark's incontinence scores varied between 7 and 12. There were no major surgical complications. Pudendal (inferior rectal) innervation of the perineally transposed antropylorus in total anorectal reconstruction is feasible and may improve outcomes in selected patients with end-stage fecal incontinence.