Could FiLaC™ be effective in the treatment of anal fistulas? A systematic review of observational studies and proportional meta-analysis

Failure rates and complications of four sphincter-sparing techniques for the treatment of fistula-in-ano: a systematic review and network meta-analysis

BACKGROUND

Several techniques are available to reduce the risk of sphincter injury when treating anal fistula, such as ligation of the intersphincteric fistula tract (LIFT), video-assisted anal fistula treatment (VAAFT), fistula laser closure (FiLaC) and endoanal flap (EAF). The aim of this meta-analysis is to provide data on the safety, complications and failure of these techniques.

METHODS

Studies published after 2017, with patients undergoing at least one among LIFT, VAAFT, FiLaC and EAF for perianal fistula and providing data regarding failure, were retrieved from PubMed and EMBASE. Primary outcome was failure; other outcomes included continence disturbance and complications.

RESULTS

Forty-nine articles with 3520 patients were included. The failure rates were 28.6% (range 3.8-75) for LIFT, 22.3% (6.2-65.2) for VAAFT, 43.9% (11.1-80) for FiLaC and 25.9% (4.7-100) for EAF, with a mean follow-up of 35.4 (6-80.4), 32.4 (6-48), 31.6(6.3-60) and 42.4 (12-155) months. The available network meta-analysis on failure showed RD of -0.08 (95% CI - 0.58 to 0.42) comparing LIFT vs VAAFT and 0.30 (95% CI 0.03 to 0.58) comparing LIFT vs EAF. No patients undergoing VAAFT or FiLaC reported worsening continence, while for LIFT and EAF, the continence disturbance rate was 1.5% and 7.3%, respectively. No major complications were observed. The most common minor complications were pain (1.4%), bleeding (1.1%) and wound infection (1.2%). Overall, minor complication rates were 4.3% for LIFT, 7.2% for VAAFT, 10.2% for FiLaC and 6.2% for EAF. Crohn's disease was associated with a higher failure rate (39.5% vs 31.4%).

CONCLUSIONS

FiLaC, VAAFT, LIFT and EAF may represent a valid option in the treatment of anal fistula. VAAFT showed the lowest rate of failure but with no differences from network metanalysis. Wider homogeneous studies with long-term follow-up are necessary to obtain more robust data.

PROSPERO NUMBER

CRD42022375600.

Systematic review and meta-analysis of the efficacy and safety of stem cell treatment of anal fistulas

BACKGROUND

Since anal fistulas can be challenging to treat; numerous innovative treatments have been proposed, including stem cell therapy. This systematic review aimed to assess pooled rates of fistula healing and adverse events associated with stem cell treatment.

METHODS

In this PRISMA-compliant systematic review we searched PubMed and Scopus for observational and randomized studies reporting outcomes of stem cell treatment for anal fistulas. The main outcome measures were successful healing and adverse effects of stem cell therapy.

RESULTS

In total, 43 studies incorporating 1160 patients (53.6% male) were included. Underlying fistula etiologies were Crohn's disease (30 studies) and cryptoglandular disease (12 studies). The main origin of stem cells was from adipose tissue (34 studies) or bone marrow (6 studies). The median follow-up duration was 12 months. The combined overall pooled healing rate was 58.1% (95% confidence interval (CI) 51.5-64.7%). The pooled healing rate for Crohn's fistulas was 60.4% (95% CI 54.7-66.2%) with adipose-derived stem cells and 63.6% (95% CI 49.4-77.7%) with bone-marrow-derived cells. The pooled healing rate for cryptoglandular fistulas was 53.8% (95% CI 35.5-72.2%) with adipose-derived stem cells. The pooled complication rate was 37.3% (95% CI 27.1-47.5%). Stem cells were associated with higher odds of anal fistula healing (odds ratio (OR): 1.81, p = 0.003) and similar odds of complications (OR: 1, p = 0.986) compared with controls.

CONCLUSIONS

Stem cell treatment of anal fistulas was associated with promising results. The healing rate in Crohn's anal fistulas was higher than in cryptoglandular fistulas. Bone-marrow-derived stem cells were associated with marginally better outcomes than were adipose-derived cells. This finding suggests that the autoimmune inflammatory etiology of Crohn's disease may respond better to autologous myoblasts than does the infectious etiology of cryptoglandular fistulas.

Management of Central Poststroke Pain: Systematic Review and Meta-analysis

Central poststroke pain (CPSP) is a neuropathic pain condition prevalent in 8 to 35% of stroke patients. This systematic review and meta-analysis aimed to provide insight into the effectiveness of available pharmacological, physical, psychological, and neuromodulation interventions in reducing pain in CPSP patients (PROSPERO Registration: CRD42022371835). Secondary outcomes included mood, sleep, global impression of change, and physical responses. Data extraction included participant demographics, stroke etiology, pain characteristics, pain reduction scores, and secondary outcome metrics. Forty-two original studies were included, with a total of 1,451 participants. No studies providing psychological therapy to CPSP patients were identified. Twelve studies met requirements for a random-effects meta-analyses that found pharmacological therapy to have a small effect on mean pain score (SMD = -.36, 96.0% confidence interval [-.68, -.03]), physical interventions did not show a significant effect (SMD = -.55 [-1.28, .18]), and neuromodulation treatments had a moderate effect (SMD = -.64 [-1.08, -.19]). Fourteen studies were included in proportional meta-analysis with pharmacological studies having a moderate effect (58.3% mean pain reduction [-36.51, -80.15]) and neuromodulation studies a small effect (31.1% mean pain reduction [-43.45, -18.76]). Sixteen studies were included in the narrative review, the findings from which largely supported meta-analysis results. Duloxetine, amitriptyline, and repetitive transcranial magnetic stimulation had the most robust evidence for their effectiveness in alleviating CPSP-induced pain. Further multicenter placebo-controlled research is needed to ascertain the effectiveness of physical therapies, such as acupuncture and virtual reality, and invasive and noninvasive neuromodulation treatments. PERSPECTIVE: This article presents a top-down and bottom-up overview of evidence for the effectiveness of different pharmacological, physical, and neuromodulation treatments of CPSP. This review could provide clinicians with a comprehensive understanding of the effectiveness and tolerability of different treatment types.

Perianal Fistula; from Etiology to Treatment - A Review

Anal fistula has been a challenging clinical issue for years due to its complex pathogenesis. The risk of frequent recurrence and incontinence complicates long-term treatment. Recent scientific literature has reviewed new techniques used for anal fistula treatment in recent years, assessing the advantages and disadvantages of each based on clinical outcomes. Although surgery is the main method used to treat anal fistula, there is no simple technique that can completely heal complex anal fistula. The surgical treatment should consider the healing outcome and the protection of anal function comprehensively. Several innovative techniques have emerged in recent years, such as combined techniques based on drainage seton and LIFT-plug, which appear to be relatively effective therapies. However, more multi-center prospective trials with long-term follow-up are needed to validate their effectiveness. In some situations, medical treatment may also be considered.

European Society of Coloproctology: Guidelines for diagnosis and treatment of cryptoglandular anal fistula

AIM

The primary aim of the European Society of Coloproctology (ESCP) Guideline Development Group (GDG) was to produce high-quality, evidence-based guidelines for the management of cryptoglandular anal fistula with input from a multidisciplinary group and using transparent, reproducible methodology.

METHODS

Previously published methodology in guideline development by the ESCP has been replicated in this project. The guideline development process followed the requirements of the AGREE-S tool kit. Six phases can be identified in the methodology. Phase one sets the scope of the guideline, which addresses the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula in adult patients presenting to secondary care. The target population for this guideline are healthcare practitioners in secondary care and patients interested in understanding the clinical evidence available for various surgical interventions for anal fistula. Phase two involved formulation of the GDG. The GDG consisted of 21 coloproctologists, three research fellows, a radiologist and a methodologist. Stakeholders were chosen for their clinical and academic involvement in the management of anal fistula as well as being representative of the geographical variation among the ESCP membership. Five patients were recruited from patient groups to review the draft guideline. These patients attended two virtual meetings to discuss the evidence and suggest amendments. In phase three, patient/population, intervention, comparison and outcomes questions were formulated by the GDG. The GDG ratified 250 questions and chose 45 for inclusion in the guideline. In phase four, critical and important outcomes were confirmed for inclusion. Important outcomes were pain and wound healing. Critical outcomes were fistula healing, fistula recurrence and incontinence. These outcomes formed part of the inclusion criteria for the literature search. In phase five, a literature search was performed of MEDLINE (Ovid), PubMed, Embase (Ovid) and the Cochrane Database of Systematic Reviews by eight teams of the GDG. Data were extracted and submitted for review by the GDG in a draft guideline. The most recent systematic reviews were prioritized for inclusion. Studies published since the most recent systematic review were included in our analysis by conducting a new meta-analysis using Review manager. In phase six, recommendations were formulated, using grading of recommendations, assessment, development, and evaluations, in three virtual meetings of the GDG.

RESULTS

In seven sections covering the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula, there are 42 recommendations.

CONCLUSION

This is an up-to-date international guideline on the management of cryptoglandular anal fistula using methodology prescribed by the AGREE enterprise.

Laser technology in proctological diseases: is it really the wave of the future?

Different types of lasers have been applied for various proctological conditions. We discuss about published articles regarding the application of lasers, with concern about evidence-based use of these techniques and technologies. We performed a literature search about laser treatments for proctological conditions. 55 studies were included for the final revision. Meta-analysis of data was not performed because of heterogeneity of study designs and outcome measures. A scoping review was performed. Laser treatments for hemorrhoids require a shorter operative time and show less postoperative pain and bleeding compared to conventional hemorrhoidectomy, but are more expensive. Studies are heterogeneous in design, endpoints, postoperative assessment, length of follow-up and outcome measures. Only 3 RCTs are available and only three studies evaluate long-term outcomes. FiLaC (fistula laser closure) was initially described in 2011 for the treatment of anal fistula. In the published studies the reported healing rates vary between 20 and 82%, and the ideal indication is yet to be defined. Studies with long-term follow-up are lacking. SiLaT (sinus laser treatment) applied the technology used for FiLaC to the treatment of pilonidal sinus disease. This technique had less perioperative pain and shorter hospital stay, but a lower primary healing rate when compared to traditional techniques. Available data is very limited, and no randomized trials are published to date. Laser assisted techniques are a viable, minimally invasive, but expensive option for the treatment of several proctological conditions. Further researches are needed to assess if patients could benefit of their use, and for what indication.

Surgery of Simple and Complex Anal Fistulae in Adults: A Review of the Literature for Optimal Surgical Outcomes

Anal fistulas are common anorectal conditions, and surgery is the primary treatment option. In the last 20 years of literature, there exist a large number of surgical procedures, especially for the treatment of complex anal fistulas, as they present more recurrences and continence problems than simple anal fistulas. To date, there are no guidelines for choosing the best technique. We conducted a recent literature review, mainly the last 20 years, based on the PubMed and Google Scholar medical databases, with the goal of identifying the surgical procedures with the highest success rates, lowest recurrence rates, and best safety profiles. Clinical trials, retrospective studies, review articles, comparative studies, recent systematic reviews, and meta-analyses for various surgical techniques, as well as the latest guidelines of the American Society of Colon and Rectal Surgeons, the Association of Coloproctology of Great Britain and Ireland, and the German S3 guidelines on simple and complex fistulas were reviewed. According to the literature, there is no recommendation for the optimal surgical technique. The etiology, complexity, and many other factors affect the outcome. In simple intersphincteric anal fistulas, fistulotomy is the procedure of choice. In simple low transsphincteric fistulas, the patient's selection is crucial in order to perform a safe fistulotomy or another sphincter-saving technique. The healing rate in simple anal fistulas is higher than 95% with low recurrence and without significant postoperative complications. In complex anal fistulas, only sphincter-saving techniques should be used; the optimal outcomes are obtained by the ligation of the intersphincteric fistulous tract (LIFT) and rectal advancement flaps. Those techniques assure high healing rates of 60-90%. The novel technique of the transanal opening of the intersphincteric space (TROPIS) is under evaluation. The novel sphincter-saving techniques of fistula laser closure (FiLac) and video-assisted anal fistula treatment (VAAFT) are safe, with reported healing rates ranging from 65% to 90%. Surgeons should be familiar with all sphincter-saving techniques in order to face the variability of the fistulas-in-ano. Currently, there is no universally superior technique that can treat all fistulas.

Does minimally invasive laser-assisted treatment of pilonidal sinus disease live up to its expectations: a multi-center study with 226 patients

PURPOSE

The minimally invasive character, the possibility to perform under local anesthesia, and the ease to repeat have led to increasing popularity of laser-assisted treatment of pilonidal sinus disease. Hereby, potentially avoiding prolonged need for medical care at home, incapacity to work, and high expenses for patients and society. This retrospective, multi-center study is aimed at evaluating the feasibility of laser-assisted treatment for pilonidal sinus disease.

METHODS

The patient population is comprised of all patients undergoing laser-assisted treatment of pilonidal sinus disease at three Belgian hospitals between January 2017 and December 2021. Data were retrospectively collected. The primary endpoint was overall wound healing after one or more laser assisted procedures.

RESULTS

A total of 226 patients were included with a mean follow-up time of 129 days [7-1120]. The healing rate after one laser procedure was 78.8%. Some of these patients were healed by a second or third procedure adding up to an overall healing rate of 85.4% after one or more laser procedures. Wound infections were the main postoperative complication (8.0%) of which 5 patients required drainage (2.2%). For 29 patients (12.8%), laser-assisted treatment was insufficient, leading to a secondary operation (drainage, excision, or flap).

CONCLUSION

This study shows that laser-assisted treatment is feasible for pilonidal sinus disease. The minimally invasive character of this technique might make up for a higher non-healing rate compared to other techniques like flap repair. However, care must be taken that healing rate might be related to the presentation of the sinus and expectations should be lowered as presumed high healing rates are not always achieved.

Prospective and multicentre study of radiofrequency treatment in anal fistula

BACKGROUND

The most effective treatment for anal fistula is fistulotomy, but it involves a risk of anal incontinence. To reduce this morbidity, sphincter-sparing treatments have been developed, but their success in real life is often less than 50%. The aim is to determine the clinical healing rate 6 months after radiofrequency treatment.

METHODS

We planned to evaluate 50 patients from three French proctology centres. Treatment efficacy was evaluated at 6 and 12 months by means of clinical and magnetic resonance imaging examination. We evaluated morbidity and healing prognostic factors.

RESULTS

Fifty patients with a mean age of 51 years (22-82) were included. Eleven patients had a low trans-sphincteric fistula (LTS), 21 patients had a high trans-sphincteric fistula (HTS), eight had a complex fistula and nine had Crohn's disease fistula. After 6 months, 17 patients (34.7%) had a clinically healed fistula, including five (45.5%) with LTS fistula, seven (33.3%) with HTS fistula, one (12.5%) with complex fistula, four (44.4%) with Crohn's disease, with no significant difference between these fistula types (p: 0.142). At 12 months, the healing rate was identical. MRI in 15 out of 17 clinically healed patients showed a deep remission of 73.3% at 12 months. Energy power was associated with the success of the treatment. There was an 8.2% incidence of post-surgical complications with 4.1% being abscesses (one required surgical management). Postoperative pain was minor. No new cases or deterioration of continence have been shown.

CONCLUSION

Radiofrequency is effective in 34.7% of the cases as an anal fistula treatment in this first prospective study, with low morbidity and no effect on continence. Clinical healing was deep (MRI) in three-quarters at 1 year. The increase in energy power during the procedure seems to be a key point to be analysed to optimise results.

Efficacy and safety of FiLaC™ for perianal fistulizing Crohn's disease: a systematic review and meta-analysis

BACKGROUND

Most patients with perianal fistulizing Crohn's disease (pfCD) present with complex types of perianal fistulas and need repetitive repair operations, resulting in a high risk of sphincter injury. Fistula-tract Laser Closure (FiLaC™) is a novel sphincter-saving technique that obliterates the fistula tract with a photothermal effect. The aim of the present systematic review and meta-analysis was to evaluate the efficacy and safety of FiLaC in pfCD.

METHODS

This study was conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Electronic databases, including PubMed, Embase, Cochrane Library and Wanfang Data were searched for published articles from January 2000 to June 2021. The clinicaltrials.gov website was searched for completed or ongoing trials on pfCD and FiLaC™. The references of each article were also searched for eligible data. The main outcome was the primary healing rate of the FiLaC™ procedure. Additionally, fecal incontinence was analyzed as the secondary outcome to evaluate the safety of FiLaC™.

RESULTS

Six studies met the eligibility criteria and were included in the final analysis. All studies were published within the past 6 years and came from European countries. There were 50 pfCD patients recruited, and 31 patients' fistulas were healed after FiLaC™. The pooled primary healing rate was 68% (95% CI 53.0-84.0%, I² = 27%, p = 0.23). There was no major fecal incontinence after surgery.

CONCLUSIONS

These data suggest that FiLaC™ may be an effective and safe procedure for pfCD patients. However, the evidence is poor and there is a need for more high-quality prospective controlled studies with long-term follow-up before this minimally invasive technique is recommended for surgical treatment of pfCD.

Treatment of cryptoglandular fistulas with the fistula tract laser closure (FiLaC™) method in comparison with standard methods: first results of a multicenter retrospective comparative study in the Netherlands

BACKGROUND

Current surgical closure techniques for sphincter-sparing treatment of high cryptoglandular fistulas in the Netherlands include the mucosal advancement flap procedure (MAF) and ligation of the intersphincteric fistula tract (LIFT). A relatively novel treatment is the fistula tract laser closure (FiLaC™) method. The aim of this study was to investigate the differences in healing and recurrence rates between FiLaC™ and current standard practices.

METHODS

This multicenter retrospective cohort study included both primary and recurrent high cryptoglandular anorectal fistulas, treated with either FiLaC™ or standard methods (MAF or LIFT) between September 2015 and July 2020. Patients with extrasphincteric fistulas, Crohn's disease, multiple fistulas, age < 18 years or missing data regarding healing time or recurrence were excluded. The primary outcomes were the clinical primary and secondary healing and recurrence rates. Primary healing was defined as a closed external opening without fluid discharge within 6 months of treatment on examination, while secondary healing was the same endpoint after secondary treatment. Secondary outcomes included healing time and complaints.

RESULTS

A total of 162 high fistulas from 3 Dutch hospitals were included. Ninety-nine high fistulas were treated with FiLaC™ and 63 with either MAF or LIFT. There were no significant differences between FiLaC™ and MAF/LIFT in terms of clinical healing (55.6% versus 58.7%, p = .601), secondary healing (70.0% versus 69.2%, p = .950) or recurrence rates (49.5% versus 54%, p = .420), respectively. Median follow-up duration was 7.1 months in the FiLaC™ group (interquartile range [IQR] 4.1-14.4 months) versus 6 months in the control group (IQR 3.5-8.1 months).

CONCLUSIONS

FiLaC™ treatment of high anorectal fistulas does not appear to be inferior to MAF or LIFT. Based on these preliminary results, FiLaC™ can be considered as a worthwhile treatment option for high cryptoglandular fistulas. Prospective studies with a longer follow-up period and well-determined postoperative parameters such as complication rates, magnetic resonance imaging for confirmation of fistula healing, incontinence and quality of life are warranted.

Emerging Data on Fistula Laser Closure (FiLaC) for the Treatment of Perianal Fistulas; Patient Selection and Outcomes

Fistula laser closure (FiLaC) is a relatively new sphincter-sparing technique in fistula surgery that was initially reported in 2011. It involves the radial dissipation of laser energy in the fistula tract and, through a combination of coagulation and shrinkage of the tract, is proposed to result in progressive sealing of fistulas. Early studies have suggested minimal impact on continence and touted the advantage of minimal morbidity with potential of repeat procedures if the technique fails initially. Despite early promising results, ten years on, questions remain on the technique, patient selection and long-term outcomes. This narrative review assesses the evidence reported to-date of radially emitting laser fistula surgery in the treatment of perianal fistulas.

Fistula Laser Closure (FiLaC™) for fistula-in-ano-yet another technique with 50% healing rates?

PURPOSE

Treatment of ano-cutaneous fistulas remains a therapeutic challenge. Fistula Laser Closure (FiLaC™) is a relatively new technique for the treatment of ano-cutaneous fistulas. This study aimed to determine the success rate of fistula closure using FiLaC™. Secondary endpoints included adverse events and patient characteristics associated with treatment success.

METHODS

This was a retrospective cohort study of consecutive patients subjected to FiLaC™ at Digestive Disease Center, Bispebjerg University Hospital, Copenhagen, between March 2017 and July 2019. All patients had a one-track fistula not suitable for fistulotomy. All were treated with a draining seton for at least 8 weeks prior to laser closure. Fistulas were ablated with a 360-degree emitting 12-watt 1470 nm laser probe. The inner fistula opening was closed with absorbable suture. All patients were followed with clinical examination including MRI or EAUS 1 year after the procedure.

RESULTS

In total, 66 patients with 68 fistulas were included. Two patients had a high intersphincteric, 20 had low transsphincteric, 41 high transsphincteric and 5 had suprasphincteric fistulas. Fistula aetiology was cryptoglandular in 83.8%, whereas the rest were due to Crohn's disease. Thirty-one (45.6%) were subjected to a second FiLaC™ procedure. Follow-up was median 19 months (12-26 months). Ultimately, 30 of 68 (44.1%) of the fistulas healed. No cases of incontinence following FiLaC™ were observed, but a single patient developed an abscess.

CONCLUSION

Fistula closure with FiLaC™ had success rates comparable to that of other sphincter-sparing techniques. The technique seems safe with respect to adverse events and risk of incontinence.

Efficacy of Permacol injection for perianal fistulas in a tertiary referral population: poor outcome in patients with complex fistulas

AIM

Injection of Permacol collagen paste can be used as a sphincter-sparing treatment for perianal fistulas. In a tertiary referral population we aimed to evaluate the efficacy of Permacol injection and the clinical and fistula-related factors associated with recurrence.

METHOD

This was a retrospective analysis of consecutive patients with perianal fistulas treated with Permacol injection at a specialist centre between June 2015 and April 2019. Endoanal ultrasonography was systematically reanalysed, blinded to treatment outcome. Rectovaginal, anovaginal and Crohn's disease fistulas were excluded. Healed fistulas were defined as absent anal symptoms and a closed external opening on physical examination at a minimum follow-up of 6 months. Regression analyses were performed to identify factors associated with unhealed fistulas.

RESULTS

A total of 90 patients (51 men; median age 45 years) were analysed. Seventy-two (80.0%) patients had complex perianal fistulas (greater than one-third sphincter involvement or multiple tracts). After a single Permacol injection, fistulas were healed in 20 (22.2%) patients at 3 months follow-up and in 18 (20.0%) patients at a median follow-up of 30 months (interquartile range 17-37). Eight (11.1%) patients with unhealed fistulas had significant improvement in their symptoms. Complex fistulas were significantly associated with unhealed status [OR 3.53 (95% CI 1.12-11.09); p = 0.031]. Twenty patients underwent subsequent Permacol injections, which were successful in six (30.0%) patients after one (n = 3) or two (n = 3) additional injections.

CONCLUSION

This largest study to date in patients with mainly complex perianal fistulas, demonstrated that the efficacy of a single Permacol injection was only 20%. Complex fistulas were associated with a poor outcome.

Case report: Complex perianal fistula treated with fistula laser closure (FILAC) and suction catheter

Introduction and importance

A patient presented with complex perianal fistula treated with fistula laser closure (FILAC) combined with suction catheters.

Case presentation

Male, 29 years old, presented in our department, presented with complex perianal fistula with a history of fistulectomy and tight seton for 6 months in another health facility. Intraoperative findings were a tract of 4,5 cm long, 4 external openings, and 1 internal opening. Definitive treatment of Fistula Laser Closure (FILAC) with 13-watt power laser diode produces by BIOLITEC German.

Conclusion

The patient recovers within 6 months. Promising results have been shown by combining FILAC and suction catheter for complex perianal fistula.

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Complex perianal fistula is a hard-to-treat diagnosis, careful approaches for its complication are needed.

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FILAC is a new sphincter-saving technique, Combination with a suction catheter promotes FILAC to achieved primary closure.

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FILAC procedure was chosen because it is a safe and effective treatment for transphinteric anal fistula

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Promising result have been shown by combining FILAC and suction catheter for complex perianal fistula