High complex anal fistula managed by the modified transanal opening of the intersphincteric space via the inter-sphincteric approach:A case report

BACKGROUND High complex anal fistulas are epithelialized tunnels,with the main fistula piercing above the deep external sphincter and the internal opening approaching the dentate line.Conventional surgical procedures for high complex anal fistulas remove most of the external sphincter and damage the anorectal ring.Postoperative loss of anal function can cause physical and mental damage.Transanal opening of the intersphincteric space(TROPIS)is an effective procedure that completely preserves the external anal sphincter.However,its clinical application is limited by challenges in the localization of the internal opening of a fistula and the high risk of complications.On the basis of our clinical experience,we modified the TROPIS procedure for the treatment of treating high complex anal fistulas.CASE SUMMARY A patient with a high complex anal fistula located above the anorectal ring underwent modified TROPIS,which involved sepsis drainage and identification of the internal opening in the intersphincteric space.The patient with the high complex anal fistula recovered well postoperatively,without any postoperative complications or anal dysfunction.Anal function returned to normal after 17 months of follow-up.CONCLUSION The modified TROPIS procedure is the most minimally invasive surgery for anal fistulas that minimally impairs anal function.It allows the complete removal of infected anal glands and reduces the risk of postoperative complications.Modified TROPIS via the intersphincteric approach is an alternative sphincter-preserving treatment for high complex anal fistulas.

Randomized controlled trial of minimally invasive surgery using acellular dermal matrix for complex anorectal fistula

AIM: To compare the efficacy and safety of acellular dermal matrix (ADM) bioprosthetic material and endorectal advancement flap (ERAF) in treatment of complex anorectal fistula. METHODS: Ninety consecutive patients with complex anorectal fistulae admitted to Anorectal Surgical Department of First Affi liated Hospital, Xinjiang Medical University from March 2008 to July 2009, were enrolled in this study. Complex anorectal fistula was diagnosed following its clinical, radiographic, or endoscopic diagnostic criteria. Under spinal anesthesia, patients underwent identification and irrigation of the fistula tracts using hydrogen peroxide. ADM was securely sutured at the secondary opening to the primary opening using absorbable suture. Outcomes of ADM and ERAF closure werecompared in terms of success rate, fecal incontinence rate, anorectal deformity rate, postoperative pain time, closure time and life quality score. Success was defined as closure of all external openings, absence of drainage without further intervention, and absence of abscess formation. Follow-up examination was performed 2 d, 2, 4, 6, 12 wk, and 5 mo after surgery, respectively. RESULTS: No patient was lost to follow-up. The overall success rate was 82.22% (37/45) 5.7 mo after surgery. ADM dislodgement occured in 5 patients (11.11%), abscess formation was found in 1 patient, and fistula recurred in 2 patients. Of the 13 patients with recurrent fistula using ERAF, 5 (11.11%) received surgical drainage because of abscess formation. The success rate, postoperative pain time and closure time of ADM were significantly higher than those of ERAF (P < 0.05). However, no difference was observed in fecal incontinence rate and anorectal deformity rate after treatment with ADM and ERAF. CONCLUSION: Closure of fistula tract opening with ADM is an effective procedure for complex anorectal fistula. ADM should be considered a first line treatment for patients with complex anorectal fistula.

Stem cell injection for complex anal fistula in Crohn’s disease: A single-center experience

BACKGROUND Despite tremendous progress in medical therapy and optimization of surgical strategies,considerable failure rates after surgery for complex anal fistula in Crohn’s disease have been reported.Therefore,stem cell therapy for the treatment of complex perianal fistula can be an innovative option with potential long-term healing.AIM To evaluate the results of local administration of allogenic,adipose-derived mesenchymal stem cells(darvadstrocel)for complex anal Crohn’s fistula.METHODS All patients with complex anal fistulas associated with Crohn’s disease who were amenable for definite fistula closure within a defined observation period were potential candidates for stem cell injection(darvadstrocel)if at least one conventional or surgical attempt to close the fistula had failed.Darvadstrocel was only indicated in patients without active Crohn’s disease and without presence of anorectal abscess.Local injection of darvadstrocel was performed as a standardized procedure under general anesthesia including single-shot antibiotic prophylaxis,removal of seton drainage,fistula curettage,closure of the internal openings and local stem cell injection.Data collection focusing on healing rates,occurrence of abscess and follow-up was performed on a regular basis of quality control and patient care.Data were retrospectively analyzed.RESULTS Between July 2018 and January 2021,12 patients(6 females,6 males)with a mean age of 42.5(range:26-61)years underwent stem cell therapy.All patients had a minimum of one complex fistula,including patients with two complex fistulas in 58.3%(7/12).Two of the 12 patients had horse-shoe fistula and 3 had one complex fistula.According to Parks classification,the majority of fistulas were transsphincteric(76%)or suprasphincteric(14%).All patients underwent removal of seton,fistula curettage,transanal closure of internal opening by suture(11/12)or mucosal flap(1/12)and stem cell injection.At a mean follow-up of 14.3(range:3-30)mo,a healing rate was documented in 66.7%(8/12);mean duration to achieve healing was 12(range:6-30)wk.Within follow-up,4 patients required reoperation due to perianal abscess(33.3%).Focusing on patients with a minimum follow-up of 12 mo(6/12)or 24 mo(4/12),long-term healing rates were 66.7%(4/6)and 50.0%(2/4),respectively.CONCLUSION Data of this single-center experience are promising but limited due to the small number of patients and the retrospective analysis.

Up-to-date meta-analysis of long-term evaluations of mesenchymal stem cell therapy for complex perianal fistula

BACKGROUND Local mesenchymal stem cell(MSC)therapy for complex perianal fistulas(PFs)has shown considerable promise.But,the long-term safety and efficacy of MSC therapy in complex PFs remain unknown.AIM To explore the long-term effectiveness and safety of local MSC therapy for complex PFs.METHODS Sources included the PubMed,EMBASE,and Cochrane Library databases.A standard meta-analysis was performed using RevMan 5.3.RESULTS After screening,6 studies met the inclusion criteria.MSC therapy was associated with an improved long-term healing rate(HR)compared with the control condition[odds ratio(OR)=2.13;95%confidence interval(95%CI):1.34 to 3.38;P=0.001].Compared with fibrin glue(FG)therapy alone,MSC plus FG therapy was associated with an improved long-term HR(OR=2.30;95%CI:1.21 to 4.36;P=0.01).When magnetic resonance imaging was used to evaluate fistula healing,MSC therapy was found to achieve a higher long-term HR than the control treatment(OR=2.79;95%CI:1.37 to 5.67;P=0.005).There were no significant differences in long-term safety(OR=0.77;95%CI:0.27 to 2.24;P=0.64).CONCLUSION Our study indicated that local MSC therapy promotes long-term and sustained healing of complex PFs and that this method is safe.