[A new treatment option for complex perianal fistulas in Crohn's disease patients; development of darvadstrocel (allogeneic expanded adipose-derived mesenchymal stem cells) in Japan].

Crohn's disease (CD) is a chronic and relapsing inflammatory bowel disease affecting the entire gastrointestinal tract. The prevalence of CD among Japanese people is increasing. One of the most frequent complications of CD is perianal fistulas. People living with CD may experience complex perianal fistulas, which can cause intense pain, bleeding, swelling, infection, and anal discharge. Despite medical and surgical advancements, complex perianal fistulas in CD remain challenging for clinicians to treat. CD patients living with perianal fistulas reported a negative impact on many aspects of their quality of life. Darvadstrocel is a cell therapy product containing a suspension of allogeneic expanded adipose-derived mesenchymal stem cells. It has been approved in Europe and Japan for the treatment of complex perianal fistulas that have shown an inadequate response to at least one conventional or biologic therapy in adult patients with non-active/mildly active luminal CD. By exhibiting immunomodulatory and local anti-inflammatory effects at the site of inflammation, it offers a new treatment option for complex perianal fistulas in CD patients. In this manuscript, the characteristic of darvadstrocel, the summary of results from the pivotal phase 3 studies in Europe and Japan, and the development strategy in Japan were introduced.

Sexual Function After Surgical Treatment for Benign Anorectal Disorders.

Benign anorectal diseases such as hemorrhoidal disease, anal fissure, anal pruritus, perianal abscess, and fistula are the most common ones. The aim of this study was to assess sexual function in patients after surgery for benign anorectal diseases. Sixty-one male patients with perianal fistulas, operated on at Department of General Surgery, Faculty of Medicine, completed a self-administered questionnaire including the International Index of Erectile Function (IIEF) score. The median IIEF score of the postoperative patients was significantly higher (24, range [10-25]) than that of preoperative patients (22, range [5-25]), p < .0001. Sexual function is significantly influenced by surgery for benign anorectal diseases.

Efficacy of surgical treatment of perianal infection in patients with hematological malignancy.

The efficacy of surgical intervention for perianal infection in patients with hematologic malignancies is not well established. Therefore, our study aimed to investigate the clinical efficacy and complications of surgical treatment of perianal infection in patients with hematologic malignancies. This retrospective study included patients with hematological malignancies who were diagnosed with perianal infections and treated at the China Aerospace Science & Industry Corporation 731 Hospital between 2018 and 2022. Patient characteristics, hematological data, surgical intervention, and complications, including recurrence and mortality, were analyzed. This study included 156 patients with leukemia aged 2 months to 71 years who were treated surgically for perianal infection, comprising 94 males and 62 females. Perianal infection included 36 cases of abscesses, 91 anal fistulas, and 29 anal fissures accompanied by infection. A total of 36 patients developed severe complications postoperatively, including 4 patients who died, 6 patients with severe incision bleeding, 18 patients with severe pain, 6 patients with sepsis, 12 patients who needed reoperation, 15 patients with hospitalization for more than 2 weeks, and 3 patients with anal stenosis; none of the patients developed anal incontinence. Additionally, risk factors for postoperative complications of perianal infection in patients with hematologic malignancies include leukopenia, agranulocytosis, thrombocytopenia, depth of abscess and not undergone an MRI. Surgical intervention may improve the prognosis of patients with perianal abscess formation, particularly in patients who show no improvement with medical therapy and those who develop perianal sepsis. Granulocytopenia and thrombocytopenia should be improved before surgery, which can significantly reduce postoperative complications. Although these findings are from a case series without a comparator, they may be of value to physicians because to the best of our knowledge, no randomized or prospective studies have been conducted on the management of perianal infections in patients with hematological malignancies.

A case-control study of the risk factors for fistula-in-ano in infants and toddlers.

BACKGROUND: Limited data are available regarding the risk factors for fistula-in-ano (FIA) in infants and toddlers, potentially affecting their daily lives. OBJECTIVES: The purpose of this study was to identify potential risk factors for FIA in infants and toddlers, in order to implement early preventive interventions, avoid disease progression, and develop therapeutic strategies. DESIGN AND SETTINGS: A retrospective case-control study was conducted, comparing 41 infants and toddlers diagnosed with FIA with 41 healthy controls, between August 2020 and December 2021. INDEPENDENT VARIABLES: (a) maternal characteristics during pregnancy and delivery, (b) perinatal characteristics, dietary behaviors, and defecation-related behaviors in infants and toddlers, (c) family dietary behaviors. RESULTS: Mothers of infants and toddlers with FIA had given birth more times in the past, while the infants and toddlers themselves had less mealtime, a higher rate of exclusive breastfeeding, frequent loose stools, and a larger proportion of used wipes, experiencing perianal skin anomalies. The logistic regression analysis revealed that there are four significant risk factors associated with the development of FIA in infants and toddlers, including the number of previous deliveries by the mother (OR 6.327), defecation frequency score (OR 5.351), stool consistency score (OR 5.017), and cleaning with wipes after defecation (OR 8.089). CONCLUSION: Based on our data, it appeared that FIA in infants and toddlers could be attributed to several factors. These included an increased number of previous deliveries by mothers, frequent loose stools, and repeated wipe use. To prevent the occurrence and worsening of the disease, it is important to improve the frequency and consistency of stooling and provide proper care. Further research is required to verify these findings in other clinical settings.

Validation of a 3D-printed model of cryptoglandular perianal fistulas.

INTRODUCTION: Visualising the course of a complex perianal fistula on imaging can be difficult. It has been postulated that three-dimensional (3D) models of perianal fistulas improve understanding of the perianal pathology, contribute to surgical decision-making and might even improve future outcomes of surgical treatment. The aim of the current study is to investigate the accuracy of 3D-printed models of perianal fistulas compared with magnetic resonance imaging (MRI). METHODS: MRI scans of 15 patients with transsphincteric and intersphincteric fistulas were selected and then assessed by an experienced abdominal and colorectal radiologist. A standardised method of creating a 3D-printed anatomical model of cryptoglandular perianal fistula was developed by a technical medical physicist and a surgeon in training with special interest in 3D printing. Manual segmentation of the fistula and external sphincter was performed by a trained technical medical physicist. The anatomical models were 3D printed in a 1:1 ratio and assessed by two colorectal surgeons. The 3D-printed models were then scanned with a 3D scanner. Volume of the 3D-printed model was compared with manual segmentation. Inter-rater reliability statistics were calculated for consistency between the radiologist who assessed the MRI scans and the surgeons who assessed the 3D-printed models. The assessment of the MRI was considered the 'gold standard'. Agreement between the two surgeons who assessed the 3D printed models was also determined. RESULTS: Consistency between the radiologist and the surgeons was almost perfect for classification (κ = 0.87, κ = 0.87), substantial for complexity (κ = 0.73, κ = 0.74) and location of the internal orifice (κ = 0.73, κ = 0.73) and moderate for the percentage of involved external anal sphincter in transsphincteric fistulas (ICC 0.63, ICC 0.52). Agreement between the two surgeons was substantial for classification (κ = 0.73), complexity (κ = 0.74), location of the internal orifice (κ = 0.75) and percentage of involved external anal sphincter in transsphincteric fistulas (ICC 0.77). CONCLUSIONS: Our 3D-printed anatomical models of perianal fistulas are an accurate reflection of the MRI. Further research is needed to determine the added value of 3D-printed anatomical models in preoperative planning and education.

A phase I/II clinical trial of ex-vivo expanded human bone marrow derived allogeneic mesenchymal stromal cells in adult patients with perianal fistulizing Crohn's Disease.

BACKGROUND: Perianal fistulas (PF) affect one-third patients with Crohn's disease (CD) with limited therapeutic options. There is dearth of literature on safety and efficacy of bone marrow-derived mesenchymal stromal cells (BMSCs) in this population. METHODS: An open-label, phase I/II, single-arm study was conducted involving local administration of human allogeneic bone marrow-derived mesenchymal stromal cells in perianal fistula of patients with Crohn's disease refractory to standard therapies. Clinical severity and biomarkers were assessed at baseline and periodically until week 104 , and MRI at week 24 and 104. Primary and secondary objectives were to assess safety and efficacy respectively. Fistula remission was complete closure of fistula openings with < 2 cm perianal collection on MRI, and fistula response was decrease in drainage by ≥ 50%. Change in perianal disease activity index, quality-of-life and Van Assche index on MRI over time was assessed using mixed-effect linear regression model. RESULTS: Ten patients (male:8, mean age:27.4 ± 12.0years) were recruited. Self-resolving procedure-related adverse events occurred in three patients, with no follow-up adverse events. In intention to treat analysis at week 24, two patients (20%) achieved fistula remission and seven (70%) had fistula response. At week 52, two (20%) patients were in remission and seven (70%) maintained response. At 104 weeks, two (20%) patients maintained response and one (10%) was in remission. Statistically significant decrease in perianal disease activity index (P = 0.008), Van Assche Index (P = 0.008) and improvement in quality-of-life (P = 0.001) were observed over time. CONCLUSIONS: Allogeneic BMSCs are safe and effective for the treatment of perianal fistulizing CD with significant improvement in clinical severity and radiological healing. TRIAL REGISTRATION: The study was prospectively registered on Clinical trials registry - India (CTRI), CTRI/2020/01/022743 on 14 January 2020, http://ctri.nic.in .

Management of anal fistulas in Crohn's disease after failure of Infliximab.

INTRODUCTION: Treatment of complex perianal fistulas in Crohn's disease remains a challenge especially after the failure of Infliximab. AIM: Update on the different therapeutic alternatives for anal fistula in Crohn's disease after failure of Infliximab. METHODS: A research in the medical literature on PubMed and Google Scholar was carried out. We included cohort studies, reviews and randomized double-blinded therapeutic trials. Case reports and fundamental research studies have been excluded. RESULTS: Anti-TNF therapy, notably Infliximab remain the therapeutic option of choice. Since Infliximab efficacy has been estimated at 60%, with a significant loss-of response rate, new therapeutic strategies have been evaluated and may offer new opportunities for the management of anal fistulas: for example, Ustekinumab could be effective after failure of anti-TNF therapy, although further studies are required. Recent guidelines suggest that injection of mesenchymal stem cells is an effective and safe treatment for complex fistulas. Other surgical options have been proposed, such as endorectal advancement flap, fibrin glue injection, anal fistula plug and ligation of the intersphincteric fistula tract, but all with limited and debatable efficacy. Given the failure rate of all these options, new strategies are currently being evaluated. CONCLUSION: Anal fistulas in Crohn's disease are a real therapeutic challenge. New medical and surgical therapies are currently being evaluated, with promising results.

Correlation between congenital pelvic floor muscle development assessed by magnetic resonance imaging and postoperative defecation.

OBJECTIVE: Children with congenital anorectal malformation (CAM) experience challenges with defecation. This study aims to assess defecation in preschool-age children with CAM and to evaluate the correlation between pelvic floor muscle developed assessed by magnetic resonance imaging (MRI) and postoperative defecation. METHODS: We collected clinical data and MRI results from 89 male children with CAM. The bowel function scores for children with Perineal (cutaneous) fistula, Rectourethral fistula(Prostatic or Bulbar), and Rectovesical fistula were computed. MRI scans were subjected to image analysis of the striated muscle complex (SMC). The association between pelvic floor muscle score and bowel function score was examined using the Cochran-Armitage Trend Test. RESULTS: We observed that 77.4% of the SMC scores by MRI for Perineal fistula were good. The Rectourethral fistula SMC score was 40.6% for moderate and 59.4% for poor. The SMC score for Rectovesical fistula was 100% for moderate. Furthermore, 77.4% of patients with Perineal fistula had bowel function scores (BFS) ≥ 17 points. Among those with Rectourethral fistula and Rectovesical fistula, 12.5% and 0 had BFS ≥ 17 points, respectively. An analysis of muscle development and bowel function in patients with Rectovesical fistula, Rectourethral fistula, and Perineal fistula revealed a correlation between SMC development and BFS. Subgroup analysis showed that the Perineal fistula had statistical significance; however, the Rectourethral fistula and Rectovesical fistula were not statistically significant. CONCLUSION: A correlation exists between pelvic floor muscle development and postoperative defecation in children with Perineal fistula.

Comparison of postoperative urinary complications in laparoscopic-assisted anorectoplasty versus posterior sagittal anorectoplasty for anorectal malformation with rectourethral fistula.

BACKGROUND: Long-term urinary outcomes after anorectal malformation (ARM) repair are affected by surgical approach and sacral anomalies. This study aimed to compare laparoscopic-assisted anorectoplasty (LAARP) and posterior sagittal anorectoplasty (PSARP) in terms of urinary complications. METHODS: Between 2001 and 2022, 45 patients were treated with LAARP or PSARP. The rectourethral fistula and inflow angle between the fistula and rectum was confirmed by preoperative colonography. The incidence of urinary complications and treatment were compared between the two groups. RESULTS: Four patients (14%) had remnant fistula and five patients (17%) had neurogenic bladder dysfunction in LAARP group, while three patients (18%) had urethral injury in PSARP group. All patients with remnant fistula were asymptomatic and followed without treatment. The incidence of remnant fistula improved between earlier decade and later decade. In all cases with urethral injury, suture repair was performed and no postoperative leakage was noted. All five patients with neurogenic bladder dysfunction had spine abnormalities that required clean intermittent catheterization (CIC) and two were free from CIC finally. CONCLUSIONS: It is important to check inflow angle preoperatively to prevent remnant fistula. For PSARP, meticulous dissection is required when separating fistula from urethra because they create common wall. The most contributing factor to neurogenic bladder is sacral anomalies. Preoperative evaluation and postoperative urinary drainage are important.

Closure of Anal Fistula with Laser- FiLaC™: a Novel Sphincter-Saving Procedure for Complex Fistula In-Ano.

There are several surgical options described for the treatment of anorectal fistulas, specially in complex cases where recurrence rates and the possibility of postoperative complications are still high. Laser- FiLaC™ has been described in this study as an option in the management of anorectal fistula. The aim of this study was to assess the novel radial laser probe treatment in complex fistula in-ano and report the success rate and recurrence rate. We studied retrospectively 56 patients who, according to our hospital patient records, underwent radial laser probe surgery between March 2019 and August 2020. In a mean follow-up time of 6 months, the success rate at 2 months was 86.0%. Most operations were done under spinal anesthesia. The recovery time was rapid and median sick leave was 7 days. Of those initially successfully treated, 3.0% developed a recurrence. Altogether 4.0% of the patients underwent a re-operation. There is a good success rate using FiLaC™ treatment. FiLaC™ is very effective in treatment of complex fistula and as well as recurrence of fistula. It has a short hospital stay and as well as it is painless surgical technique that should be largely used in our country.

Self-screening questionnaire for perianal fistulizing disease in patients with Crohn's disease.

BACKGROUND/AIMS: A poor prognostic factor for Crohn's disease (CD) includes perianal fistulizing disease, including perianal fistula and/or perianal abscess. Currently, a tool to assess perianal symptoms in patients with CD remains nonexistent. This study aimed to develop a perianal fistulizing disease self-screening questionnaire for patients with CD. METHODS: This prospective pilot study was conducted at three tertiary referral centers between January 2019 and May 2020. We formulated questions on perianal symptoms, including tenesmus, anal discharge, bleeding, pain, and heat. A 4-point Likert scale was used to rate each question. Patients with CD completed a questionnaire and underwent pelvic magnetic resonance imaging (MRI). RESULTS: Overall, 93 patients were enrolled, with 51 (54.8%) diagnosed with perianal fistulizing disease, as determined by pelvic MRI. The Spearman correlation findings demonstrated that anal pain (p = 0.450, p < 0.001) and anal discharge (p = 0.556, p < 0.001) were the symptoms that most significantly correlated with perianal disease. For anal pain and discharge, the area under the receiver operating characteristic curve of the scores was significantly higher than that of the combined score for all five symptoms (0.855 vs. 0.794, DeLong's test p = 0.04). For the two symptoms combined, the sensitivity, specificity, and positive predictive and negative predictive values were 88.2, 73.8, 80.4, and 83.8%, respectively, with 81.7% accuracy for detecting perianal fistulizing disease. CONCLUSION: This study indicates that simple questions regarding anal pain and discharge can help accurately identify the presence of perianal fistulizing disease in patients with CD.

Anal Cryptoglandular Suppuration: Evidence-Based Management.

Anal suppurative processes are commonly encountered in surgical practice. While the initial therapeutic intervention is philosophically straightforward (incision and drainage), drainage of the appropriate space and treatment of the subsequent fistula in ano require a thorough understanding of perianal anatomy and nuanced decision making. Balancing the risk of fecal incontinence with simple fistulotomy versus the higher risk of fistula recurrence with all sphincter-sparing fistula treatments can be a challenge for surgeons and patients alike.

Dynamic contrast-enhanced MR imaging in identifying active anal fistula after surgery.

BACKGROUND: It is challenging to identify residual or recurrent fistulas from the surgical region, while MR imaging is feasible. The aim was to use dynamic contrast-enhanced MR imaging (DCE-MRI) technology to distinguish between active anal fistula and postoperative healing (granulation) tissue. METHODS: Thirty-six patients following idiopathic anal fistula underwent DCE-MRI. Subjects were divided into Group I (active fistula) and Group IV (postoperative healing tissue), with the latter divided into Group II (≤ 75 days) and Group III (> 75 days) according to the 75-day interval from surgery to postoperative MRI reexamination. MRI classification and quantitative analysis were performed. Correlation between postoperative time intervals and parameters was analyzed. The difference of parameters between the four groups was analyzed, and diagnostic efficiency was tested by receiver operating characteristic curve. RESULTS: Wash-in rate (WI) and peak enhancement intensity (PEI) were significantly higher in Group I than in Group II (p = 0.003, p = 0.040), while wash-out rate (WO), time to peak (TTP), and normalized signal intensity (NSI) were opposite (p = 0.031, p = 0.007, p = 0.010). Area under curves for discriminating active fistula from healing tissue within 75 days were 0.810 in WI, 0.708 in PEI, 0.719 in WO, 0.783 in TTP, 0.779 in NSI. All MRI parameters were significantly different between Group I and Group IV, but not between Group II and Group III, and not related to time intervals. CONCLUSION: In early postoperative period, DCE-MRI can be used to identify active anal fistula in the surgical area. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR2000033072.

LIFT procedure: postoperative outcomes, risk factors for fistula recurrence and continence impairment.

Ligation of the intersphincteric fistula tract has been recently employed as definitive treatment of anal fistulas. However, it carries a potential risk of continence impairment, fistula recurrence, and repeated operations. This study aimed to assess postoperative outcomes related to this procedure and evaluate the potential influence of preoperative and intraoperative features. Patients who underwent LIFT procedure between June 2012 and September 2021 were retrospectively analyzed. Patients were divided according to whether they developed fistula recurrence and on the history of a surgery prior to the LIFT. Preoperative features, postoperative outcomes, and risk factors adverse outcomes were analyzed. Forty-eight patients were included, of which 25 received primary LIFT, being the high transsphincteric fistula pattern the most frequent (62.5%). The median follow-up was 13.3 months, with a recurrence rate of 20.8%, of which the majority presented an intersphincteric fistula pattern (50%); and continence impairment rate of 16.7%. A higher prevalence of diabetes (p = 0.026) and a trend towards a higher prevalence of patients with a history of high transsphincteric fistula (0.052) were observed in the group with fistula recurrence. The history of diabetes and the operation time with a cut-off value ≥ 69 min showed a trend as a risk factors for developing fistula recurrence (0.06) and postoperative continence impairment (0.07), respectively. The LIFT procedure seems to be safe in terms of morbidity, with a reasonable incidence of recurrences, showing better results when it is primarily performed. Preoperative characteristics should be considered as they may impact outcomes.

Transanal fistula repair for the treatment of rectovestibular fistula with normal anus in female children: a 5-year single-center experience.

PURPOSE: The purpose of this study was to review a 5-year operative experience of transanal fistula repair for the treatment of rectovestibular fistula with a normal anus in female children. METHODS: In this study, we conducted a retrospective review of children diagnosed with rectovestibular fistula with normal anus who underwent transanal fistula repair in the department of General Surgery, Children's Hospital of Chongqing Medical University. Clinical data were retrospectively analyzed. RESULTS: A total of 56 female children were included in the study. The patients' ages ranged from 1 year 10 months to 15 years 11 months, with an average age of 5 years 1 month. These children had a clear history of gas or loose stool leakage through the vestibular area, with or without a history of vestibular infection. All patients had a normal anus and underwent transanal fistula repair. Follow-up was conducted through telephone or outpatient visits for a duration of 10 months to 5 years (average follow-up duration 19 months). Three patients experienced minimal secretion from the external orifice of the vestibular fistula within two weeks after the operation, but were successfully treated with sitting bath therapy without any relapse. Another three cases had a recurrence of the fistula, and two of them underwent transanal fistula repair at our center again, resulting in a successful cure after reoperation. The remaining case has not yet undergone reoperation. In the long-term follow-up, all the children had satisfactory anal appearance, with no fecal incontinence, anorectal stenosis, or fistula infection. CONCLUSION: Transanal fistula repair is a simple, safe, and effective surgical method to treat female children with rectovestibular fistula with a normal anus.

Ligadura del trayecto fistuloso interesfinteriano. Nuestros resultados / Ligation of the intersphincteric fistulatract. Our results

Introducción: existen varias técnicas para el tratamiento quirúrgico de las fístulas anales, con variables resultados. La técnica de ligadura del trayecto fistuloso interesfinteriano (LIFT) consiste en la disección del espacio entre ambos esfínteres para localizar el trayecto fistuloso y proceder a su ligadura y sección. Objetivo: evaluar nuestros resultados con la técnica de LIFT para del tratamiento de las fístulas anales transesfinterianas. Diseño: retrospectivo, observacional de corte transversal. Materiales y métodos: Se incluyeron todos los pacientes con fístulas transesfinterianas tratados con LIFT desde enero de 2013 a diciembre 2020. El seguimiento postoperatorio se realizó hasta los 2 años. Resultados: se operaron 62 pacientes. El sexo predominante fue masculino. Hubo 47 pacientes con fístulas transesfinterianas bajas y 15 con fístulas transesfinterianas altas. En todos se identificó el trayecto fistuloso realizándose ligadura de ambos cabos del trayecto interesfinteriano y se procedió a un curetaje del trayecto a través del orificio externo. Cinco pacientes (8%) presentaron dehiscencia de piel a nivel de la incisión del espacio interesfinteriano, manejado en forma conservadora. Este grupo tuvo una cicatrización mas retardada de 4 semanas. Ocurrió recidiva en 22 (35,5%) pacientes. Conclusión: La técnica de LIFT parece una alternativa eficaz y segura para el tratamiento de las fístulas transesfinterianas bajas y altas ya que no altera la anatomía ni la continencia. (AU)

Introduction: there are various techniques for the surgical treatment of anal fistulas, with variable results. The ligation procedure of the intersphincteric fistulous tract (LIFT) consists of dissecting the space between both sphincters to locate the fistulous tract and proceed to its ligation and section. Objective: to evaluate our results with the LIFT procedure for the treatment of transsphincteric anal fistulas. Design: retrospective, cross-sectional observational study. Material and methods: all patients with transsphincteric fistulas treated with LIFT from January 2013 to December 2020 were included. Postoperative follow-up was carried out for up to 2 years. Results: sixty-two patients underwent surgery. The predominant sex was male. There were 47 patients with low transsphincteric fistulas and 15 with high transsphincteric fistulas. After identifying the fistulous tract in the intersphincteric groove, both ends were ligated and the tract was cut. Finally, curettage of the tract through the external orifice was performed. Five patients (8%) presented skin dehiscence at the level of the intersphincteric groove incision, managed conservatively. This group had a longer healing time of four weeks. Recurrence occurred in 22 (35.5%) patients. Conclusion: the LIFT procedure appears to be an effective and safe alternative for the treatment of low and high transsphincteric fistulas, since it does not alter the anatomy or continence. (AU)

Protocol of the LATFIA trial (Laser Assisted Treatment of Fistula in Ano): a multicentre, prospective, randomized controlled trial comparing fistula-tract laser closure (FiLaC™) with rectal advancement flap for high trans-sphincteric fistulas.

AIM: Anal fistula is one of the most common anal diseases, affecting between 1 and 3 per 10 000 people per year. Symptoms have a potentially severe effect on a patient's quality of life. Surgery is the mainstay of treatment, aiming to cure the fistula and preserve anal sphincter function. Rectal advancement flap (RAF) is currently the gold standard treatment but has recurrence rates varying between 20% and 50% and might lead to disturbance of continence. The aim of the trial described in this work is to discover if the minimally invasive fistula tract laser closure (FiLaC™) technique could achieve higher healing rates and a better functional outcome than RAF. METHOD: We will perform a randomized prospective multicentre noninferiority study of the treatment of high trans-sphincteric perianal fistulas, comparing FiLaC™ with RAF in terms of fistula healing, recurrence rate, functional outcome and quality of life. Primary and secondary fistula healing will be evaluated at 26 and 52 weeks' follow-up. Quality of life will be evaluated using the SF-36 questionnaire, the Faecal Incontinence Quality of Life Scale questionnaire and the Vaizey score at 3, 6, 12 and 26 weeks postoperatively. CONCLUSION: High trans-sphincteric fistulas have a potentially severe effect on a patient's quality of life. Classical treatment with RAF is a time-consuming invasive procedure. The LATFIA trial aims to compare FiLaC™ with the gold standard treatment with RAF. In case of noninferiority, FiLaC™ treatment could be standardized as a first line treatment for high trans-sphincteric fistulas. Better conservation of the patient's anal sphincter function could possibly be obtained. Likewise, we will report on the postoperative quality of life when applying these two techniques.