Modified Anorectal Surgery Based On New Understanding Of Pelvic Anatomy

Chapter 1 Urogenital fascia-sparing TME for rectal cancer: a study on anatomical basis and clinical efficacyBackgroundHeald first described total mesorectal excision(TME)in 1982.At present,TME has become the standard procedure for the treatment of mid-low rectal cancer.However,the anatomy posterior to the rectum in TME remains controversial.According to Heald’s description,the free avascular plane behind the rectum during TME for rectal cancer is called the "Holy plane",which is located between the pelvic visceral fascia(Visceral)and the parietal fascia(Somatic).Since then,different scholars have made different understandings of the fascia and space posterior to the rectum,and even confusion has arisen in the naming of the fascia.Meanwhile,the relationship between the fascia around the rectum and the hypogastric nerve is described by different scholars in different ways.Therefore,it is very necessary to carry out a detailed and accurate description of the fascia structure and nerve course behind the rectum,so as to determine the true "Holy plane" of TME.In recent years,with the popularization of laparoscopic colorectal surgery,subtle anatomical structures can be identified during surgery,creating favorable conditions for the in-depth study of pelvic anatomy.This study uses autopsy combined with anatomical observation in laparoscopic colorectal surgery to accurately describe the anatomical structure of the fascia around the rectum and the relationship between the fascia and nerves;therefore," Urogenital Fascia-sparing TME for Rectal Cancer " is proposed.This procedure was further validated by retrospective clinical study for its safety and efficacy.ObjectiveTo describe the anatomical basis of “Urogenital Fascia-sparing TME for Rectal Cancer”,and to verify the safety and efficacy of the procedure.Method1.Anatomical observations were implemented on 26 adult cadaver specimens and 61 video data of laparoscopic colorectal surgery.2.The clinical data of 212 patients with mid-low rectal cancer who underwent laparoscopic radical resection in Shanghai Yangpu District Central Hospital from July 2014 to March 2018 were collected,and the surgical results were analyzed.Urinary function was assessed using postvoid residual urine volume(PVR)and International Prostatic Symptom Score(IPSS).Sexual function was assessed using the Chinese index of erectile function(CIEF)and the female sexual function index(FSFI).Result1.Anatomical findingsThe fascia propria of the rectum(FPR)appears as a thin layer of fascia surrounding the rectum and its blood vessels and adipose tissue.The visceral fascia and the urogenital fascia are anatomically the same structure.There are two avascular planes behind the rectum,one is the plane between FPR and visceral fascia,and the other is the plane between the visceral fascia and the parietal fascia.The hypogastric nerve runs in the visceral fascia.The visceral fascia moves from the posterior to the anterior and merges with the Denonvilliers’ fascia,and the pelvic plexus is lateral to this junction.2.Surgical resultsFor 212 patients with mid-low rectal cancer,the mean operation time,blood loss and postoperative hospital stay were 156±38 minutes,76±13 m L and 7±3.3 days,respectively.Surgical pathology showed no cases with positive margins,and the average number of harvested lymph nodes was 14±1.6.Postoperative complications occurred in 23 patients(10.8%),including 11 patients(5.2%)with anastomotic leakage,9 patients with intestinal obstruction(4.2%),and 7 patients with surgical site infection(3.3%),with no perioperative death.Local tumor recurrence occurred in 9 patients(4.2%),and distant metastasis occurred in 30 patients(14.2%)within 3 years after surgery.Thirteen patients(6.1%)had moderate voiding dysfunction(IPSS score 13.6±3.4),and there was no significant difference in IPSS score before and after surgery(P>0.05),and 13 patients(6.1%)had PVR>50m L.Erectile dysfunction occurred in 18(13.5%)male patients.Sexual dysfunction occurred in 5(6.3%)female patients.There was no significant difference in CIEF or FSFI scores before and after surgery(P>0.05).Conclusion1.The fascia propria of the rectum(FPR)and the visceral fascia are two separate layers of fascia.The urogenital fascia is anatomically the same structure as the visceral fascia.The hypogastric nerve runs in the urogenital fascia.Therefore,the true "holy plane" of TME should be located between FPR and urogenital fascia.The urogenital fascia(visceral fascia)should be preserved rather than removed during TME surgery.2.Urogenital fascia-sparing TME for rectal cancer is with good oncological effects and low incidence of complications,and the incidence of postoperative urinary and sexual dysfunction is low.This procedure was proven to be safe and effective for the treatment of mid-low rectal cancer.Chapter 2 VAAFT for complex anal fistula: Anatomical basis and clinical efficacyBackgroundThe management of complex anal fistula(CAF)has always been a challenge for anorectal surgeons.Fistulotomy plus seton(FPS)is a commonly used surgical procedure,but its main complication is anal incontinence.The mechanism of anal incontinence is thought to be caused by intraoperative injury to the anal sphincter.A correct understanding of the anatomical structure of the anal sphincter and the mechanism of continence will help to promote the continuous improvement of anal fistula surgery and reduce the occurrence of postoperative anal incontinence.As one of the sphincter-preserving procedures,video-assisted anal fistula treatment(VAAFT),first reported by Meinero,has the main advantage of allowing direct visualization of the fistula from the inside,allowing identification of the internal opening and eradication of extensions,with no damage to the anal sphincter.Our team took the lead in carrying out VAAFT in China,and the preliminary results confirmed the feasibility and safety of VAAFT for complex anal fistula.However,there are very few studies comparing VAAFT with other surgical procedures,and the effect of VAAFT for complex anal fistula needs further evaluation.The present study aims to accurately describe the anal sphincter complex through autopsy observation,explain the anatomical basis of anal incontinence caused by anal fistula surgery,and then further used a retrospective clinical study to compare the efficacy of VAAFT and FPS for complex anal fistula,and in addition to evaluate the postoperative incontinence.ObjectiveTo describe the anatomical basis of anal incontinence caused by anal fistula surgery,and to compare the safety and efficacy of VAAFT and FPS for complex anal fistula.Method1.twenty-six adult cadavers were dissected,observing the anatomical structure of the muscles around the anus.2.One hundred and forty-eight CAF patients who received VAAFT or FPS in Shanghai Yangpu District Central Hospital from January 2017 to December 2018 were included.Propensity score matching(PSM)analysis was performed on the patients’ baseline characteristics,and the surgical outcomes between the matched groups were compared.Logistic regression was performed to analyze the risk factors of fistula recurrence after VAAFT.Result1.The anorectal ring formed by puborectalis muscle,external sphincter and internal sphincter plays an important role in anal continence.Any manipulation that disrupts the integrity of the sphincter may lead to anal incontinence.2.Sixty-eight and eighty patients received VAAFT and FPS,respectively.After PSM,64 matched patient pairs were created.Compared with FPS,VAAFT was more efficient in locating the internal opening(90.6% vs.100%),less intraoperative blood loss(26±15 vs.12±5 m L),and lower postoperative bleeding rate(10.9% vs.1.5%),shorter postoperative hospital stay(6.8±5.1 vs.5.0±3.3 days),less postoperative pain,and less wound secretion(all P<0.05).At 3 months postoperatively,fistula recurrence was observed in 10(15.6%)and nine(14.1%)patients undergoing VAAFT and FPS,respectively,with no significant difference(P = 1.000).The Wexner incontinence score of VAAFT was significantly lower than that of FPS(0.9±1.7 vs.1.9±2.6,P=0.003).A total of 12 patients(17.6%)had fistula recurrence in all VAAFT patients.Logistic analysis showed that multiple fistulas,prolonged operation time and severe postoperative wound secretion were independent risk factors(OR = 2.18,3.25 and 3.04,respectively,all P <0.05).Conclusion1.Traditional anal fistula surgery results in interruption of sphincter continuity and impairment of sphincter function,which is the anatomical basis for anal incontinence.2.VAAFT for complex anal fistula has the advantages of less injury,less pain,faster recovery,fewer complications,and better sphincter preservation.Multiple fistulas,prolonged operative time and severe postoperative wound secretions were independent risk factors for recurrence after VAAFT.