Structured magnetic resonance imaging and endoanal ultrasound anal fistulas reporting template(SMART):An interdisciplinary Delphi consensus

BACKGROUND There is still considerable heterogeneity regarding which features of cryptoglandular anal fistula on magnetic resonance imaging(MRI)and endoanal ultrasound(EAUS)are relevant to surgical decision-making.As a con-sequence,the quality and completeness of the report are highly dependent on the training and experience of the examiners.AIM To develop a structured MRI and EAUS template(SMART)reporting the minimum dataset of information for the treatment of anal fistulas.METHODS This modified Delphi survey based on the RAND-UCLA appropriateness for consensus-building was conducted between May and August 2023.One hundred and fifty-one articles selected from a systematic review of the lite-rature formed the database to generate the evidence-based statements for the Delphi study.Fourteen questions were anonymously voted by an interdisciplinary multidisciplinary group for a maximum of three iterative rounds.The degree of agreement was scored on a numeric 0–10 scale.Group consensus was defined as a score≥8 for≥80%of the panelists.RESULTS Eleven scientific societies(3 radiological and 8 surgical)endorsed the study.After three rounds of voting,the experts(69 colorectal surgeons,23 radiologists,2 anatomists,and 1 gastroenterologist)achieved consensus for 12 of 14 statements(85.7%).Based on the results of the Delphi process,the six following features of anal fistulas were included in the SMART:Primary tract,secondary extension,internal opening,presence of collection,coexisting le-sions,and sphincters morphology.CONCLUSION A structured template,SMART,was developed to standardize imaging reporting of fistula-in-ano in a simple,systematic,time-efficient way,providing the minimum dataset of information and visual diagram useful to refer-ring physicians.

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.

A case study illustrating the use of an integrated approach to treat secondary Anal Fistula Post I&D of Perianal Abscess

Background:Anal fistula is a long-term disease characterized by a tubular structure with one end opening in the anorectal canal and the other end opening on the surface of the perineum or perianal skin with chronic pus drainage.It is linked to Bhagandar in Ayurveda,and in Sushruta Samhita,Acharya has mentioned 5 forms of Bhagandar.The boil in the present case was Shukla,sthira i.e.hard and firm,with Picchila strava and Kandu resembling the features of Parisraavi bhagandar.Aim and objective:The current case was diagnosed as Parisravi bhagandar,which resembles trans-sphincteric or intersphincteric fistula in modern ano.In Ayurveda,the management of Parisraavi Bhagandar,Shastra,kshara,and Agnikarma is advised and the use of Ksharasutra,which contributes to complete cutting and healing of the track without reoccurrence,similarly Modern surgeon depends on surgery i.e radical excision of the track,ligation with Seton,and use of chemical irritants like urethane,silver nitrates,etc.A cutting seton(tight)gently slices the confined muscle to close the fistula with the least interruption to continence.This operation is especially advised when a one-stage fistulotomy poses a considerable risk of incontinence.Material and methods:The method performed here was Core Partial Fistulectomy followed by Ksharasutra application till complete healing of the wound.Discussion and conclusion:This case study provides the successful management of Parisraavi Bhagandara(high anal,trans-sphincteric fistula in ano)in 61-year-old male patient with an integrated surgical&Ayurvedic management approach.

Clinical Study on the Treatment of Low Anal Fistula in Infants and Young Children by Anal Gland Excision and Virtual Hanging Procedure

Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision.

Observation on Curative Effect of Self-made Wubeizi Decoction Combined with rhaFGF in Promoting Postoperative Wound Healing in Patients with Anal Fistula

[Objectives]To explore the curative effect of Self-made Wubeizi Decoction combined with recombinant human acidic fibroblast growth factor(rhaFGF)in promoting postoperative wound healing in patients with anal fistula.[Methods]A total of 82 patients with anal fistula who underwent anal fistula resection+use of setons in Luodian Hospital during January and March of 2020 were randomly divided into observation group and control group with 41 cases in each group.The control group was given rhaFGF external application regimen,and the observation group was treated with Self-made Wubeizi Decoction on the basis of the control group.After 3 weeks of treatment,the differences in curative effects of TCM syndromes were compared between the two groups.Besides,the changes in TCM symptom scores,inflammatory mediators[interleukin-12(IL-12),tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ)],anorectal functions[anal resting pressure(ARP),maximal systolic pressure(MSP)and maximum tolerated volume(MTV)of the anal canal],quality of life[GQOLI-74 scores]were compared.[Results]After 3 weeks of treatment,the total effective rate of the observation group was significantly higher than that of the control group(P<0.05);the levels of TCM symptom scores,IL-12,TNF-α,IFN-γ,ARP,MSP,and MTV in both groups were significantly lower than those before treatment,and these levels in the observation group was significantly lower than that in the control group at the same time(P<0.05).The GQOLI-74 scores of both groups were significantly higher than those before treatment,and the observation group was significantly higher than the control group(P<0.05).[Conclusions]The Self-made Wubeizi Decoction combined with rhaFGF therapy has a significant effect in promoting postoperative wound healing in patients with anal fistula.It can effectively inhibit the local inflammation of patients,facilitate the recovery of anorectal function and improve the quality of life,thus has high clinical application value.

Diagnostic performance of texture analysis in the differential diagnosis of perianal fistulising Crohn’s disease and glandular anal fistula

BACKGROUND Perianal fistulising Crohn's disease(PFCD)and glandular anal fistula have many similarities on conventional magnetic resonance imaging.However,many patients with PFCD show concomitant active proctitis,but only few patients with glandular anal fistula have active proctitis.AIM To explore the value of differential diagnosis of PFCD and glandular anal fistula by comparing the textural feature parameters of the rectum and anal canal in fat suppression T2-weighted imaging(FS-T2WI).METHODS Patients with rectal water sac implantation were screened from the first part of this study(48 patients with PFCD and 22 patients with glandular anal fistula).Open-source software ITK-SNAP(Version 3.6.0,http://www.itksnap.org/)was used to delineate the region of interest(ROI)of the entire rectum and anal canal wall on every axial section,and then the ROIs were input in the Analysis Kit software(version V3.0.0.R,GE Healthcare)to calculate the textural feature parameters.Textural feature parameter differences of the rectum and anal canal wall between the PFCD group vs the glandular anal fistula group were analyzed using Mann-Whitney U test.The redundant textural parameters were screened by bivariate Spearman correlation analysis,and binary logistic regression analysis was used to establish the model of textural feature parameters.Finally,diagnostic accuracy was assessed by receiver operating characteristic-area under the curve(AUC)analysis.RESULTS In all,385 textural parameters were obtained,including 37 parameters with statistically significant differences between the PFCD and glandular anal fistula groups.Then,16 texture feature parameters remained after bivariate Spearman correlation analysis,including one histogram parameter(Histogram energy);four grey level co-occurrence matrix(GLCM)parameters(GLCM energy_all direction_offset1_SD,GLCM entropy_all direction_offset4_SD,GLCM entropy_all direction_offset7_SD,and Haralick correlation_all direction_offset7_SD);four texture parameters(Correlation_all direction_offset1_SD,cluster prominence_angle 90_offset4,Inertia_all direction_offset7_SD,and cluster shade_angle 45_offset7);five grey level run-length matrix parameters(grey level nonuniformity_angle 90_offset1,grey level nonuniformity_all direction_offset4_SD,long run high grey level emphasis_all direction_offset1_SD,long run emphasis_all direction_offset4_SD,and long run high grey level emphasis_all direction_offset4_SD);and two form factor parameters(surface area and maximum 3D diameter).The AUC,sensitivity,and specificity of the model of textural feature parameters were 0.917,85.42%,and 86.36%,respectively.CONCLUSION The model of textural feature parameters showed good diagnostic performance for PFCD.The texture feature parameters of the rectum and anal canal in FS-T2WI are helpful to distinguish PFCD from glandular anal fistula.

Research Progress of Traditional Chinese and Western Medicine Dressing Change on Wound Healing After Anal Fistula Surgery

With the change of people’s lifestyle and diet,the incidence of anorectal diseases is increasing year by year.Anal fistula is a common anorectal disease.Because it cannot heal by itself,surgery has become the main treatment method.Due to the particularity of wound location and physiological structure,the wound is easily contaminated by bacteria,so dressing change after surgery plays a decisive role in wound healing.Modern western medicine and traditional Chinese medicine have different dressing changing methods respectively.In this paper,we reviewed commonly used dressing changing methods of traditional Chinese and western medicine after anal fistula surgery.

Treatment of peri-anal fistula in Crohn's disease

Anal fistulas are a common manifestation of Crohn's disease(CD). The first manifestation of the disease is often in the peri-anal region, which can occur years before a diagnosis, particularly in CD affecting the colon and rectum. The treatment of peri-anal fistulas is difficult and always multidisciplinary. The European guidelines recommend combined surgical and medical treatment with biologic drugs to achieve best results. Several different surgical techniques are currently em-ployed. However, at the moment, none of these tech-niques appear superior to the others in terms of healing rate. Surgery is always indicated to treat symptomatic, simple, low intersphincteric fistulas refractory to medi-cal therapy and those causing disabling symptoms. Ut-most attention should be paid to correcting the balance between eradication of the fistula and the preservationof fecal continence.

Why do we have so much trouble treating anal fistula?

Anal fistula is among the most common illnesses affecting man.Medical literature dating back to 400 BC has discussed this problem.Various causative factors have been proposed throughout the centuries,but it appears that the majority of fistulas unrelated to specific causes (e.g.Tuberculosis,Crohn’s disease) result from infection (abscess) in anal glands extending from the intersphincteric plane to various anorectal spaces.The tubular structure of an anal fistula easily yields itself to division or unroofing (fistulotomy) or excision (fistulectomy) in most cases.The problem with this single,yet effective,treatment plan is that depending on the thickness of sphincter muscle the fistula transgresses,the patient will have varying degrees of fecal incontinence from minor to total.In an attempt to preserve continence,various procedures have been proposed to deal with the fistulas.These include: (1) simple drainage (Seton);(2) closure of fistula tract using fibrin sealant or anal fistula plug;(3) closure of primary opening using endorectal or dermal flaps,and more recently;and (4) ligation of intersphincteric fistula tract (LIFT).In most complex cases (i.e.Crohn’s disease),a proximal fecal diversion offers a measure of symptom-atic relief.The fact remains that an "ideal" procedure for anal fistula remains elusive.The failure of each sphincter-preserving procedure (30%-50% recurrence) often results in multiple operations.In essence,the price of preservation of continence at all cost is multiple and often different operations,prolonged disability and disappointment for the patient and the surgeon.Nevertheless,the surgeon treating anal fistulas on an occasional basis should never hesitate in referring the patient to a specialist.Conversely,an expert colorectal surgeon must be familiar with many different operations in order to selectively tailor an operation to the individual patient.

Three-dimensional endoanal ultrasonographic assessment of an anal fistula with and without H_2O_2 enhancement

AIM： To evaluate the effectiveness of three-dimensional endoanal ultrasound （3D-EAUS） in the assessment of anal fistulae with and without H202 enhancement. METHODS： Sixty-one patients （37 males, aged 17-74 years） with anal fistulae, which were not simple low types, were evaluated by physical examination and 3D-EAUS with and without enhancement. Fistula classification was determined with each modality and compared to operative findings as the reference standard. RESULTS： The accuracy of 3D-EAUS was significantly higher than that of physical examination in detecting the primary tract （84.4% vs 68.7%, P = 0.037） and secondary extension （81.8% vs 62.1%, P = 0.01） and localizing the internal opening （84.2% vs 59.7%, P = 0.004）. A contrast study with H202 detected several more fistula components including two primary suprasphincteric fistula tracks and one supralevator secondary extension, which were not detected on non-contrast study. However, there was no significant difference in accuracy between 3D-EAUS and H202- enhanced 3D-EAUS with respect to classification of the primary tract （84.4% vs 89.1%, P = 0.435） or secondary extension （81.8% vs 86.4%, P = 0.435） or localization of the internal opening （84.2% vs 89.5%, P = 0.406）. CONCLUSION： 3D-EAUS was highly reliable in the diagnosis of an anal fistula. H2O2 enhancement was helpful at times and selective use in difficult cases may be economical and reliable.

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.

Lessons learned from an audit of 1250 anal fistula patients operated at a single center:A retrospective review

BACKGROUND A complex anal fistula is a challenging disease to manage.AIM To review the experience and insights gained in treating a large cohort of patients at an exclusive fistula center.METHODS Anal fistulas operated on by a single surgeon over 14 years were analyzed.Preoperative magnetic resonance imaging was done in all patients.Four procedures were performed:fistulotomy;two novel sphincter-saving procedures,proximal superficial cauterization of the internal opening and regular emptying and curettage of fistula tracts(PERFACT)and transanal opening of intersphincteric space(TROPIS),and anal fistula plug.PERFACT was initiated before TROPIS.As per the institutional GFRI algorithm,fistulotomy was done in simple fistulas,and TROPIS was done in complex fistulas.Fistulas with associated abscesses were treated by definitive surgery.Incontinence was evaluated objectively by Vaizey incontinence scores.RESULTS A total of 1351 anal fistula operations were performed in 1250 patients.The overall fistula healing rate was 19.4%in anal fistula plug(n=56),50.3%in PERFACT(n=175),86%in TROPIS(n=408),and 98.6%in fistulotomy(n=611)patients.Continence did not change significantly after surgery in any group.As per the new algorithm,1019 patients were operated with either the fistulotomy or TROPIS procedure.The overall success rate was 93.5%in those patients.In a subgroup analysis,the overall healing rate in supralevator,horseshoe,and fistulas with an associated abscess was 82%,85.8%,and 90.6%,respectively.The 90.6%healing rate in fistulas with an associated abscess was comparable to that of fistulas with no abscess(94.5%,P=0.057,not significant).CONCLUSION Fistulotomy had a high 98.6%healing rate in simple fistulas without deterioration of continence if the patient selection was done judiciously.The sphincter-sparing procedure,TROPIS,was safe,with a satisfactory 86%healing rate for complex fistulas.This is the largest anal fistula series to date.

Traditional Chinese surgical treatment for anal fistulae with secondary tracks and abscess

AIM:To evaluate the efficacy and safety of traditional Chinese surgical treatment for anal fistulae with secondary tracks and abscess.METHODS:Sixty patients with intersphincteric or transsphincteric anal fistulas with secondary tracks and abscess were randomly divided into study group [suture dragging combined with pad compression(SDPC)] and control group [fistulotomy(FSLT)].In the SDPC group,the internal opening was excised and incisions at external openings were made for drainage.Silk sutures were put through every two incisions and knotted in loose state.The suture dragging process started from the first day after surgery and the pad compression process started when all sutures were removed as wound tissue became fresh and without discharge.In the FSLT group,the internal opening and all tracts were laid open and cleaned by normal saline postoperatively till all wounds healed.The time of healing,postoperative pain score(visual analogue scale),recurrence rate,patient satisfaction,incontinence evaluation and anorectal manometry before and after the treatment were examined.RESULTS:There were no significant differences between the two groups regarding age,gender and fistulae type.The time of healing was significantly shorter(24.33 d in SDPC vs 31.57 d in FSLT,P < 0.01) and the patient satisfaction score at 1 mo postoperative followup was significantly higher in the SDPC group(4.07 in SDPC vs 3.37 in FSLT,P < 0.05).The mean maximal postoperative pain scores were 5.83 ± 2.5 in SDPC vs 6.37 ± 2.33 in FSLT and the recurrence rates were 3.33 in SDPC vs 0 in FSLT.None of the patients in the two groups experienced liquid and solid fecal incontinence and lifestyle alteration postoperatively.The Wexner score after treatment of intersphincter fistulae were 0.17 ± 0.41 in SDPC vs 0.40 ± 0.89 in FSLT and transsphincter fistulae were 0.13 ± 0.45 in SDPC vs 0.56 ± 1.35 in FSLT.The maximal squeeze pressure and resting pressure declined after treatment in both groups.The maximal anal squeeze pressures after treatment were reduced(23.17 ± 3.73 Kpa in SDPC vs 22.74 ± 4.47 Kpa in FSLT) and so did the resting pressures(12.36 ± 2.15 Kpa in SDPC vs 11.71 ± 1.87 Kpa in FSLT),but there were neither significant differences between the two groups and nor significant differences before or after treatment.CONCLUSION:Traditional Chinese surgical treatment SDPC for anal fistulae with secondary tracks and abscess is safe,effective and less invasive.

Guidelines on postoperative magnetic resonance imaging in patients operated for cryptoglandular anal fistula:Experience from 2404 scans

Magnetic resonance imaging(MRI)is considered the gold standard for the evaluation of anal fistulas.There is sufficient literature available outlining the interpretation of fistula MRI before performing surgery.However,the interpretation of MRI becomes quite challenging in the postoperative period after the surgery of fistula has been undertaken.Incidentally,there are scarce data and no set guidelines regarding analysis of fistula MRI in the postoperative period.In this article,we discuss the challenges faced while interpreting the postoperative MRI,the timing of the postoperative MRI,the utility of MRI in the postoperative period for the management of anal fistulas,the importance of the active involvement and experience of the treating clinician in interpreting MRI scans,and the latest advancements in the field.

Comparison between recent sphincter-sparing procedures for complex anal fistulas-ligation of intersphincteric tract vs transanal opening of intersphincteric space

Complex anal fistulas are difficult to treat.The main reasons for this are a higher recurrence rate and the risk of disrupting the continence mechanism because of sphincter involvement.Due to this,several sphincter-sparing procedures have been developed in the last two decades.Though moderately successful in simple fistulas(50%-75%healing rate),the healing rates in complex fistulas for most of these procedures has been dismal.Only two procedures,ligation of intersphincteric fistula tract and transanal opening of intersphincteric space have been shown to have good success rates in complex fistulas(60%-95%).Both of these procedures preserve continence while achieving high success rates.In this opinion review,I shall outline the history,compare the pros and cons,indications and contraindications and future application of both these procedures for the management of complex anal fistulas.

Efficacy of Kegel exercises in preventing incontinence after partial division of internal anal sphincter during anal fistula surgery

BACKGROUND The transanal opening of intersphincteric space(TROPIS)procedure,performed to treat complex anal fistulas,preserves the external anal sphincter(EAS)but involves partial incision of the internal anal sphincter(IAS).AIM To ascertain the incidence of incontinence after the division of the IAS as is done in TROPIS and to evaluate whether regular Kegel exercises(KE)in the postoperative period can prevent incontinence due to IAS division.METHODS Patients operated on for high complex fistulas and having no preoperative continence problem(score=0)were included in the study.All patients were operated on by the TROPIS procedure and were recommended KE(pelvic contraction exercises)50 times/day.KE were commenced on the 10^(th)postoperative day and continued for 1 year.Incontinence was evaluated objectively(by modified Vaizey’s scores)in the immediate postoperative period(Pre-KE group)and on long-term follow-up(Post-KE group).The incontinence scores in both groups were compared to evaluate the efficacy of KE.RESULTS Of 102 anal fistula patients operated on between July 2018 and July 2020 were included in this study.There were 90 males,the mean age was 42.3±12.8,and the median follow-up was 30 mo(18-42 mo).Three patients were lost to follow-up.There were 65 recurrent fistulas,92 had multiple tracts,42 had associated abscess,46 had horseshoe fistula and 34 were supralevator fistulas.All were magnetic resonance imaging-documented high fistulas(>1/3 EAS involved).Overall incontinence occurred in 31%patients(Pre-KE group)with urge and gas incontinence accounting for the majority of cases(28.3%).The mean incontinence scores in the Pre-KE group were 1.19±1.96(in 31 patients,solid=0,liquid=7,gas=8,urge=24)and in the Post-KE group were 0.26±0.77(in 13 patients,solid=0,liquid=2,gas=3,urge=10)(P=0.00001,t-test).CONCLUSION Division of the IAS led to incontinence,mainly urge incontinence,and also to a mild degree of gas and liquid incontinence.However,regular KE led to a significant reduction in incontinence(both in the number of affected patients and the severity of scores in these patients).

Guidelines to diagnose and treat peri-levator high-5 anal fistulas: Supralevator, suprasphincteric, extrasphincteric, high outersphincteric, and high intrarectal fistulas

Supralevator,suprasphincteric,extrasphincteric,and high intrarectal fistulas(high fistulas in muscle layers of the rectal wall)are well-known high anal fistulas which are considered the most complex and extremely challenging fistulas to manage.Magnetic resonance imaging has brought more clarity to the pathophysiology of these fistulas.Along with these fistulas,a new type of complex fistula in high outersphincteric space,a fistula at the roof of ischiorectal fossa inside the levator ani muscle(RIFIL),has been described.The diagnosis,management,and prognosis of RIFIL fistulas is reported to be even worse than supralevator and suprasphincteric fistulas.There is a lot of confusion regarding the anatomy,diagnosis,and management of these five types of fistulas.The main reason for this is the paucity of literature about these fistulas.The common feature of all these fistulas is their complete involvement of the external anal sphincter.Therefore,fistulotomy,the simplest and most commonly performed procedure,is practically ruled out in these fistulas and a sphincter-saving procedure needs to be performed.Recent advances have provided new insights into the anatomy,radiological modalities,diagnosis,and management of these five types of high fistulas.These have been discussed and guidelines formulated for the diagnosis and treatment of these fistulas for the first time in this paper.

Diagnosis of anorectal tuberculosis by polymerase chain reaction,GeneXpert and histopathology in 1336 samples in 776 anal fistula patients

BACKGROUND The association of tuberculosis(TB)with anal fistulas can make its treatment quite difficult.The main challenge is timely detection of TB in anal fistulas and its proper management.There is little data available on diagnosis and management of TB in anal fistulas.AIM To detect TB in fistula-in-ano patients were analyzed in different methods utilized.METHODS A retrospective analysis of different methods,polymerase chain-reaction(PCR),GeneXpert and histopathology(HPE),utilized to detect tuberculosis in fistula-inano patients,treated between 2014-2020,was performed.The sampling was done for tissue(fistula tract lining)and pus(when available).The detection rate of various tests to detect TB and prevalence rate of TB in simple vs complex fistulae were studied.RESULTS In 1336 samples(776 patients)tested,TB was detected in 133 samples(122 patients).TB was detected in 52/703(7.4%)samples tested by PCR-tissue,in 77/331(23.2%)samples tested by PCR-pus,3/197(1.5%)samples tested with HPE-tissue and 1/105(0.9%)samples tested by GeneXpert.To detect TB,PCRtissue was significantly better than HPE-tissue(52/703 vs 3/197 respectively)(P=0.0012,significant,Fisher’s exact test)and PCR-pus was significantly better than PCR-tissue(77/331 vs 52/703 respectively)(P<0.00001,significant,Fisher’s exact test).TB fistulas were more complex than non-tuberculous fistulas[78/113(69%)vs 278/727(44.3%)respectively](P<0.00001,significant,Fisher’s exact test)but the overall healing rate was similar in tuberculous and non-tuberculous fistula groups[90/102(88.2%)vs 518/556(93.2%)respectively](P=0.10,not significant,Fisher’s exact test).CONCLUSION This is the largest study of anorectal TB to be published.The detection of TB by polymerase chain-reaction was significantly higher than by histopathology and GeneXpert.Amongst polymerase chain-reaction,pus had a higher detection rate than tissue.TB fistulas were more complex than non-tuberculous fistulas but aggressive diagnosis and meticulous treatment led to comparable overall success rates in both groups.

Magnetic resonance imaging findings of carcinoma arising from anal fistula: A retrospective study in a single institution

BACKGROUND Magnetic resonance imaging(MRI)is currently the standard investigation for suspected perianal diseases.Carcinoma arising from anal fistula is very rare,and early diagnosis is often difficult.AIM To describe and summarize the MRI findings of carcinoma arising from anal fistula.METHODS In this retrospective study,records of ten patients diagnosed with carcinoma arising from anal fistula and confirmed by surgery(n=7)or biopsy(n=3)between June 2006 and August 2018 were analyzed.All patients underwent preoperative pelvic MRI.Morphologic features,signal characteristics,fistula between the mass and the anus,contrast enhancement of mass,signal and enhancement of peritumoral areas,and regional lymphadenopathy were assessed.RESULTS All ten tumors were solitary(8 mucinous adenocarcinomas and 2 adenocarcinomas).The maximum diameter of the tumors ranged from 3.4 cm to 12.4 cm(median:4.15 cm;mean:5.68 cm).Eight patients had a fistula between the mass and the anus.Contrast enhancement of the peritumoral areas was noted in three(3/5)patients.Perirectal or inguinal lymphadenopathy was noted in seven patients.Most lesions of mucinous adenocarcinoma were multiloculated and cauliflower-like,with a thin capsule and focally unclear boundary.They were markedly hyperintense on fat-suppressed T2WI,slightly hyperintense with focal hyperintensity on diffusion-weighted imaging(DWI),and hyperintense with focal hypointensity on apparent diffusion coefficient(ADC)map,with progressive mesh-like contrast enhancement.Adenocarcinomas had an infiltrative margin without a capsule and appeared heterogeneously hyperintense or slightly hyperintense on fat-suppressed T2WI,hyperintense on DWI,and hypointense on ADC map,with persistent heterogeneous enhancement.CONCLUSION Our study highlighted several characteristic and potentially helpful MRI findings to diagnose carcinomas arising from anal fistula.

Including video and novel parameter-height of penetration of external anal sphincter-in magnetic resonance imaging reporting of anal fistula

The main purpose of a radiologist’s expertise in evaluation of anal fistula magnetic resonance imaging(MRI)is to benefit patients by decreasing the incontinence rate and increasing the healing rate.Any loss of vital information during the transfer of this data from the radiologist to the operating surgeon is unwarranted and is best prevented.In this regard,two methods are suggested.First,a short video to be attached with the standardized written report highlighting the vital parameters of the fistula.This would ensure minimum loss of information when it is conveyed from the radiologist to the operating surgeon.Second,inclusion of a new parameter,the amount of external sphincter involvement by the anal fistula.This parameter is usually not included in the MRI report.This can be evaluated as the height of penetration of the external anal sphincter(HOPE)by the fistula.The external anal sphincter plays a pivotal role in maintaining continence.This parameter(HOPE)is distinct from the‘height of internal opening’and assumes immense importance as its knowledge is paramount to prevent damage to the external anal sphincter by the surgeon during surgery.