Long-term outcomes of Fistula Laser Closure (FiLaC ® ) with a 1470 nm diode laser for cryptoglandular anal fistula

Long-term outcomes of Fistula Laser Closure (FiLaC ® ) with a 1470 nm diode laser for cryptoglandular anal fistula | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Long-term outcomes of Fistula Laser Closure (FiLaC ® ) with a 1470 nm diode laser for cryptoglandular anal fistula Jingyi Zhu, Zhicheng Li, Lei Jin, Xiyue Zhang, Jiong Wu, Zhenyi Wang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5296816/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective The aim of this study was to evaluate the long-term efficacy of Fistula Laser Closure (FiLaC®)with using a 1470 nm diode laser in the treatment of cryptoglandular anal fistula. Methods Data of patients with cryptoglandular anal fistula who underwent FiLaC® in our department between September 2017 and December 2019 were retrospectively analyzed. Demographic data, perioperative data and postoperative data were collected and statistically analyzed. Results A total of 52 patients who met the inclusion criteria were included in the study. The cure rates at 1month, 1 year, and 5 years were 96.2% (50/52), 82.7% (43/52), and 76.9% (40/52), respectively. The differences among the internal opening position subgroups were statistically significant ( P = 0.018), with the bilateral type having a higher cure rate than the anterior and posterior types (86.2%, 75% and 37.5%, respectively). No statistically significant differences were observed between the subgroups: Parks classification, number of internal openings, closure of internal openings, treatment of internal openings, number of external openings, relative position of internal and external openings, presence of straight fistula, and presence of blind fistula. All the scores, including visual analogue scale pain score (VAS-PS), cleveland clinic florida incontinence score (CCF-IS), and the quality of life in patients with anal fistula questionnaire score (QoLAF-QS), showed a gradual increase over time, followed by a subsequent decrease. Discussion Although the cure rate of the FiLaC® technique is inferior to that of traditional surgery, the FiLaC® technique has significant advantages in reducing the postoperative pain, the risk of fecal incontinence, and the postoperative quality of life. Furthermore, the FiLaC® technique is more suitable for cryptoglandular anal fistulas with an internal opening located on both sides or behind the anal canal. This study provides a preliminary evaluation of the FiLaC® technique, and we hope to increase the cure rate in the future by observing improvements in surgical methods, laser burning power, laser burning time and other aspects. Fistula Laser Closure 1470 nm diode laser cryptoglandular anal fistula long-term outcomes Figures Figure 1 1 Introduction Anal fistula is a pathological passage located in close proximity to anal canal and rectum. It is typically caused by an infection of the anal gland. Anal fistula has become a common clinical disease and the incidence rate has increased to 18.4 cases per 100,000 population [ 1 ]. At present, this disease cannot be cured by drugs and can only be treated by surgery. The incidence rate is higher in males than in females. We usually use Park’s classification to define different types of anal fistulas which contains the following four types: inter⁃sphincteric fistula, trans⁃sphincteric fistula, supra⁃sphincteric fistula, extra⁃sphincteric fistula. Among them, the inter⁃sphincteric and trans⁃sphincteric types are the most common ones. In the past, surgeons have used traditional technologies to treat this disease, such as fistulotomy, fistulectomy, seton placement therapy and so on. However, in recent years, surgeons are adopting new technologies to overcome the low recurrence rate and the high incontinence rate caused by traditional techniques. In order to maintain a high cure rate, the traditional methods would damage the function of the anal sphincters. Consequently, one of the major research focuses is how to protect anal sphincter function while removing fistula. Researches have shown that new technologies, such as ligation of the inter-sphincteric fistula tract (LIFT) [ 2 ], endoanal advancement flap (ERAF) [ 3 ], video assisted anal fistula treatment (VAAFT) [ 4 ], and others, have significantly reduced the risk of anal incontinence. On the other hand, the new ones have certain drawbacks, such as low cure rates (less than 50%) [ 5 ]. Although it is difficult to increase the cure rate, the fistula laser closure (FiLaC®) for anal fistula, which has emerged in recent years, has shown a better clinical effect. FiLaC® was originally proposed by Wilhelm in 2011 [ 6 ]. By using a guidewire to quickly heat and vaporize the epithelial surfaces of fistula, the fistula can be treated. And research has also shown that the cure rate of this technique is higher than other novel techniques (71–82%) [ 7 – 9 ]. Therefore, we want to observe the efficacy and safety of FilaC ® in treating inter⁃sphincteric and trans⁃sphincteric fistulas. 2 Materials and methods Experimental design and test objects We conducted a prospective study using a prospective cohort which included 52 patients with cryptoglandular anal fistula between September 2017 and December 2019. The clinical trial was granted by the Chinese Clinical Trial Registry (No. ChiCTR-IOR-17012085). Ethical approval was granted by the ethics committee of Yueyang Hospital of Integrated Traditional Chinese and Western Medicine affiliated to Shanghai University of Traditional Chinese Medicine (No. 2017-033). Written informed consent was obtained from each participant. All procedures were carried out in accordance with relevant guidelines and regulations. Inclusion criteria: (1) Those who meet the diagnostic criteria for anal fistula in the 2016 American Association of Colorectal Surgeons' Clinical Diagnosis and Treatment Guidelines for Perianal Abscess, Anal Fistula, and Rectovaginal Fistula. (2) Those who have been indicated to have an inter⁃sphincteric or trans⁃sphincteric fistula by perianal magnetic resonance imaging. (3) Those with obvious fibrotic anal fistula. (4) Age range: 18–65 years. Exclusion criteria: (1) Patients with perianal abscess. (2) Patients with concomitant colorectal malignancy, intestinal tuberculosis, or vaginal fistula. (3) Patients with coagulation dysfunction. (4) Patients with chronic diseases such as hypertension and diabetes. (5) Individuals during menstruation, pregnancy, or lactation. Interventions All patients received a preoperative intestinal preparation and underwent hair removal on the evening before the surgical procedure, which was performed using the FiLaC ® technique. We used Leonardo DUAL 45 laser equipment (Biolitec AG, Germany) with fixed power (12W) and fixed wavelength (1470 nm). Firstly, we inserted a 360 ° dual ring diode laser fiber from the external opening to the internal opening. Then the fiber was pulled out at a constant speed of 1 mm/s while allowing the fiber to continuously release energy. At last, the external opening was removed in a suitable manner for postoperative drainage, based on the size of the incision. (Fig. 1 .) Result evaluation 2.1.1 Primary and secondary results The primary outcomes included the 1-month cure rate, the 1-year cure rate, the 5-year cure rate, Visual Analog Scale Pain Score (VAS-PS) and Cleveland Clinic Florida Incontinence Score (CCF-IS) [ 10 – 11 ]. The healing criterion was postoperative wound healing (without local redness, swelling, heat, pain, or pus discharge). Postoperative pain was measured using an 11-point Visual Analog Scale Pain Score (VAS-PS). The severity of fecal incontinence symptoms was evaluated using the Cleveland Clinic Florida Incontinence Score (CCF-IS). The secondary outcomes included the Quality of Life in Patients with Anal Fistula Questionnaire score (QoLAF-QS) [ 12 ], Bristol Stool Chart and postoperative complications. The Quality of Life in Patients with Anal Fistula Questionnaire score (QoLAF-QS) was used to assess the quality of life of patients with anal fistula. Stool consistency was assessed using the 7-point Bristol Stool Scale [ 13 ]. 2.1.2 Demographic data, perioperative data, and observation indicators We collected baseline demographic data including sex, age, duration of disease, body mass index (BMI), internal and external opening positions, Parks’ classification, fistula diameter, and internal opening height (the distance from the internal opening to the anal edge). Additionally, we also collected perioperative data including American Society of Anesthesiologists score, burning energy, burning time, postoperative fluid properties, and postoperative complications. Furthermore, we collected observation indicators including the primary and secondary outcomes. 2.1.3 Follow-up methods Data was collected through outpatient follow-up for 1 month, 1 year, and 5 years after surgery. The data pertaining to the observation indicators was collected on the 1st, 3rd, 7th, 30th and 90th days postoperatively, and at 1-, 5-year intervals thereafter. Data Analysis Statistical analysis was performed using SPSS Statistics 25.0 software (IBM Inc., IL, USA). Continuous variables were presented as either the mean ± standard deviation (SD) or the median with interquartile range (IQR) based on the distribution. The independent t-test was used to compare normally distributed continuous variables, whereas the Mann-Whitney U test was used to compare non-normally distributed continuous variables. Categorical data were expressed as the number of cases and percentages. A value of p < 0.05 was deemed to indicate a statistically significant difference. 3 Results Demographic data The differences in sex, age, course of disease, BMI, Parks’ classification, fistula diameter, and internal opening height between the two groups were not statistically significant (all P > 0.05) and were comparable. The results are shown in Table 1 . Table 1 Comparison of patient demographics and characteristics Variables Laser group (n = 52) Sex, n (%) Male Female 41 (78.8) 11 (21.2) Age, y [M ( P 25 , P 75 )] 38.7 (31,44) Disease course, m [M ( P 25, P 75 )] 8.23 (1.5,12) Body mass index, kg/m 2 [M ( P 25 , P 75 )] 24.6 (22.6,26.3) The position of internal opening Front type 6 (11.5) Bilateral type 32 (61.5) Posterior type 14 (26.9) The status of internal opening Closed 22 (42.3) Opened 30 (57.7) Parks’ classification, n (%) Inter-sphincteric fistula Trans-sphincteric fistula 12 (23.1) 40 (76.9) Fistula diameter, cm [M ( P 25 , P 75 )] 3.2(2.8,4.0) Internal opening height, cm [M ( P 25 , P 75 )] 33.0(27.5,38.5) The statistical significance of Parks’ classification was found to differ between the two groups ( P 0.05). The differences in the treatment methods of the internal opening and fistula between the two groups were statistically significant (both P < 0.000). The results are shown in Table 2 . Table 2 Comparison of patient perioperative data Variables Laser group (n = 52) ASA score a Ⅰ Ⅱ 52 (98.1) 1 (1.9) The treatment of internal opening Suture 14 (26.9) Incision 8 (15.4) Suture combined with incision 2 (3.8) None 28 (53.8) The treatment of anal fistula Incision 9 (17.3) Excision 1 (1.9) Laser ablation 42 (80.8) The hanging of anal fistula Virtual thread-hanging 2 (3.8) Shallow thread-hanging 1 (1.9) Both 0 (0.0) None 49 (94.2) a ASA score: American Society of Anesthesiologists Score Primary and Secondary Results The cure rates at 1month, 1 year, and 5 years were 96.2% (50/52), 82.7% (43/52), and 76.9% (40/52), respectively. The difference among internal-opening-position subgroups was statistically significant ( P = 0.018), and the cure rate of the bilateral type was higher than the anterior and posterior types(86.2%, 75% and 37.5%, respectively). The results are shown in Table 3 . Table 3 Comparison of outcomes between patients with different types of Parks’ classification Outcomes Inter-sphincteric fistula Trans-sphincteric fistula Statistical value P value Laser group, n (%) Cure Relapse 9 (75.0) 3 (25.0) 28 (75.7) 9 (24.3) X 2 = 0.002 0.962 There was no statistically significant difference between the subgroups: the Parks’ classification, number of internal openings, closure of internal openings, treatment of internal openings, number of external openings, relative position of internal and external openings, presence of straight fistula and presence of blind fistula. The results are shown in Table 4 . Table 4 Comparison of outcomes among patients with different positions of internal opening Outcomes Front type a Bilateral type a Posterior type a Statistical value P value Laser group, n (%) Cure Relapse 3 (37.5) 5 (62.5) 25 (86.2) 4 (13.8) 9 (75.0) 3 (25.0) X 2 = 8.046 0.018 a The position of internal opening All the scores (VAS-PS, CCF-IS, and QoLAF-QS) increased gradually over time and subsequently decreased. The results are shown in Table 5 . Table 5 Comparison of perioperative scores. (Score, x ± s) Variables Laser group (n = 52) VAS⁃PS PRD 0.8 ± 0.7 POD 1 2.3 ± 1.3 POD 3 1.0 ± 0.7 POD 7 0.2 ± 0.4 POD 30 0.2 ± 0.4 POD 90 0.2 ± 0.4 POD 1-year 0.2 ± 0.4 POD 5-year 0.1 ± 0.3 CCF⁃IS PRD 1.0 ± 1.2 POD 1 1.3 ± 1.5 POD 3 1.4 ± 1.5 POD 7 1.4 ± 1.4 POD 30 0.8 ± 1.1 POD 90 0.8 ± 1.0 POD 1-year 0.2 ± 0.5 POD 5-year 0.2 ± 0.1 QoLAF⁃QS PRD 17.2 ± 1.8 POD 1 21.6 ± 5.0 POD 3 19.5 ± 3.1 POD 7 17.7 ± 2.4 POD 30 18.3 ± 2.6 POD 90 17.6 ± 2.6 POD 1-year 16.1 ± 1.7 POD 5-year 15.8 ± 2.0 Abbreviations: PRD = preoperative day; POD = postoperative day; CCF-IS = Cleveland Clinic Florida incontinence score; VAS-PS = Visual Analog Scale pain score; QoLAF-QS = Quality of Life in Patients with Anal Fistula Questionnaire score. Table 6 Comparison of laser data in various literature. Study Patients Energy, watts success rate(%) Wihelm (2011) 11 13 81.8 Giamundo (2013) 35 10–13(980nm) 71.4 Ôzturk (2014) 50 15 82.0 Giamundo (2015) 45 12 71.7 Wilhelm (2017) 10 13 64.0 Terzi (2017) 103 12 40.0 Lauretta (2018) 30 12 33.3 Brabender (2019) 18 10–14 22.0 Bonnechose(2020) 100 13 44.6 Sluckin(2022) 162 13 55.6 Lara Blanco Teres (2024) 36 12 55.6 Current study 53 12 77.4 Efficacy assessment After 76.5 (59–84) months of follow-up with FiLaC®, clinical healing was observed in 40 patients (76.9%), while unhealed or recurrent fistulas were observed in 12 patients (23.1%) during the follow-up period. Among the 12 patients with fistula recurrence, 5 patients had fistulas that reappeared at the surgical site, while the other 7 patients had fistulas that reappeared at other surgical sites. Of the 5 patients 8 were cured. 4 Discussion The main difficulty in treating anal fistula is the balance between the removal of lesions and the preservation of anal sphincters. The FiLaC® technique is a new sphincter-saving surgery that achieves the purpose of treatment by closing the anal fistula after ablation. It was found that the primary cure rate of the modified FiLaC® technique (combined with ERAF) was 64.1%, and the secondary cure rate was 88%. Giamundo conducted a retrospective analysis of 180 patients who underwent the FiLaC® procedure. The results showed that the cure rates of the primary operation and the second operation were 66.8% and 73.7%, respectively. Other studies have shown that the cure rates of FiLaC® technique rang from 22–82% [ 14 – 16 ]. There is no established consensus regarding the optimal type of surgery and indications for the FiLaC® technique. The studies are shown in Table 7. To avoid recurrence, fistulotomy is usually performed by making an incision along the anal fistula using an electric scalpel. This allows for adequate visualization of the foci and adequate dressing changes of the inflamed tissues. This causes significant damage to the anal sphincter, leading to postoperative pain and sphincter dysfunction. To make up for the defects of traditional surgery, the FiLaC® technique uses a guidewire to quickly heat and vaporize the epithelial surfaces of fistulas. The following reasons may contribute to the low cure rate of laser group. (1) The FiLaC® technique treats the internal opening with laser ablation, which causes the internal opening to shrink and local protein denaturation. During postoperative tissue healing, feces may infect the unhealed wound, leading to the recurrence of anal fistula. This hypothesis is also consistent with the findings of Giamundo et al. [ 17 ] and Wilhelm et al. who suggested that the treatment of the internal opening is particularly important for postoperative healing of anal fistula. (2) In terms of fistula management, the FiLaC® technique makes it impossible to continue coking the inflammatory tissue below the coking layer after the surface tissue has been charred. Therefore, there is still room for localization of inflammation in fistulas with severe inflammation infiltration or complex shapes. Researches have shown that laser fistulectomy is more suitable for simple fistulas less than 30 millimeters. The fiber diameter is 1.8mm and the laser penetration depth is 2 to 3mm. It is not possible to directly observe the internal situation of the fistula during surgery. If the diameter of the fistula is too large, the laser will not completely burn the epithelial tissue of the tube wall, making it difficult to evenly ablate the fistula. If the diameter of the fistula is too small, the superficial tissues and skin are more likely to be damaged during burning than in traditional fistula resection surgery, where the situation of fistula resection can directly observed. In addition, the laser catheter is more suitable for straight fistulas because the tip of the catheter is not tough enough to bend. In contrast, it increases the difficulty of the operation in curved or branched fistulas [ 18 ]. Therefore, in the laser closure of anal fistula, the selection of laser energy should be adapted to the position and wall thickness of the fistula, and the optimal parameters should be chosen as the core of laser treatment for anal fistula [ 19 ]. In addition, the results of this study showed that there was no statistically significant difference in the cure rate of anal fistula between the two. The sample size of patients with sphincter-type anal fistula may be small, and further large-scale clinical studies are needed to confirm this. We also recognize that there are certain limitations of this study. Firstly, this study is a prospective analysis with a limited number of cases, and all included patients have Parks I and II anal fistulas. Therefore, further large-scale prospective experimental studies are needed to clarify its optimal indications. Secondly, in terms of the treatment of the internal opening, we can optimize the following plan: (1) for patients with a large and fibrotic internal opening, internal opening resection should be performed before laser closure; (2) if the internal opening is small and not fibrotic, laser closure should be used and then the internal opening sutured with 3 − 0 Vico suture; (3) patients with non-fibrotic and pseudo-closed internal opening were treated with laser closure alone. In conclusion, the FiLaC® technique is suitable for cryptoglandular anal fistula with an internal opening located on both sides or behind the anal canal. It can significantly reduce postoperative pain, lower the rate of anal incontinence and improve patients' postoperative quality of life. However, considering that this study is only a single center retrospective study, prospective bulk case studies can be conducted in the future. Abbreviations CCF-IS Cleveland Clinic Florida Incontinence Score ERAF Endoanal Advancement Flap FiLaC® Fistula Laser Closure LIFT the Inter-sphincteric Fistula Tract QoLAF-QS the Quality of Life in Patients with Anal Fistula Questionnaire score VAAFT Video Assisted Anal Fistula Treatment VAS-PS Visual Analog Scale pain score. Declarations Author Contribution Jingyi Zhu and Zhicheng Li wrote the main manuscript text and Jingyi Zhu prepared figures 1. All authors reviewed the manuscript. Acknowledgements This work was supported by the Science and Technology Commission of Shanghai Municipality (Grant No. 20Y21901200) (to J.W.), a grant from the National Natural Science Foundation of China (Grant No. 82274531) (to Z.W.). Data availability The data sets generated and analysed in this study are not publicly available due to the sensitive data regulations of our institutional policy, but a de-identified data could be available from the first author (Dr. JY Zhu) upon reasonable request. References Mazier WP. The treatment and care of anal fistulas: a study of 1,000 patients. Dis Colon Rectum. 1971;14(2):134–144. doi: 10.1007/BF02560060 Celayir MF, Bozkurt E, Aygun N, Mihmanli M. Complex Anal Fistula: Long-Term Results of Modified Ligation of Intersphincteric Fistula Tract = LIFT. Sisli Etfal Hastan Tip Bul. 2020;54(3):297–301. Published 2020 Aug 24. doi: 10.14744/SEMB.2020.89106 Yellinek S, Krizzuk D, Moreno Djadou T, Lavy D, Wexner SD. Endorectal advancement flap for complex anal fistula: does flap configuration matter?. Colorectal Dis. 2019;21(5):581–587. doi: 10.1111/codi.14564 Emile SH, Elfeki H, Shalaby M, Sakr A. 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Tech Coloproctol. 2019;23(12):1127–1132. doi: 10.1007/s10151-019-02112-9 Giamundo P, Esercizio L, Geraci M, Tibaldi L, Valente M. Fistula-tract Laser Closure (FiLaC™): long-term results and new operative strategies. Tech Coloproctol. 2015;19(8):449–453. doi: 10.1007/s10151-015-1282-9 Isik O, Gulcu B, Ozturk E. Long-term Outcomes of Laser Ablation of Fistula Tract for Fistula-in-Ano: A Considerable Option in Sphincter Preservation. Dis Colon Rectum. 2020;63(6):831–836. doi: 10.1097/DCR.0000000000001628 Chand M, Tozer P, Cohen RC. Is FiLaC the answer for more complex perianal fistula?. Tech Coloproctol. 2017;21(4):253–255. doi: 10.1007/s10151-017-1621-0 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5296816","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":368566196,"identity":"2ac4bf92-e063-4ff8-8a3b-92d3622ed498","order_by":0,"name":"Jingyi Zhu","email":"","orcid":"","institution":"Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Affiliated to Shanghai University of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Jingyi","middleName":"","lastName":"Zhu","suffix":""},{"id":368566197,"identity":"81536f7b-45cb-4422-aec5-6e891305b660","order_by":1,"name":"Zhicheng Li","email":"","orcid":"","institution":"Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Affiliated to Shanghai University of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Zhicheng","middleName":"","lastName":"Li","suffix":""},{"id":368566198,"identity":"e4f2efb7-4daf-4c6e-8784-cdebb875a1d9","order_by":2,"name":"Lei Jin","email":"","orcid":"","institution":"Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Affiliated to Shanghai University of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Lei","middleName":"","lastName":"Jin","suffix":""},{"id":368566199,"identity":"b5717bd3-cd9f-4f96-b5a8-912e9193ea86","order_by":3,"name":"Xiyue Zhang","email":"","orcid":"","institution":"Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Affiliated to Shanghai University of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Xiyue","middleName":"","lastName":"Zhang","suffix":""},{"id":368566200,"identity":"b9ac3387-224a-4ab5-bf0a-cd6488d127fe","order_by":4,"name":"Jiong Wu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAw0lEQVRIiWNgGAWjYBCDBAYG5oMPEipqCCvlgWoAamFLNnhw5hhJWnjMJB+2MBPWYs9+OvHBzx82efzSZ8wqEhvYGPjbuxPw28KTu9mwJyGtWLIvrexG4g4ZBokzZzfg1yLBu02aIeFw4oYzzNtuJJ5hYzCQyCVSy/4zDGYFiW3MJGjZwMNixkCcljMgv6SlFUucYUuWSDhzjIegX9jbz2588MMGGGI9zAc//qiokeNv78WvBdNa0pSPglEwCkbBKMAKAPqfRY47SjdxAAAAAElFTkSuQmCC","orcid":"","institution":"Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Affiliated to Shanghai University of Traditional Chinese Medicine","correspondingAuthor":true,"prefix":"","firstName":"Jiong","middleName":"","lastName":"Wu","suffix":""},{"id":368566201,"identity":"8193c522-980b-45d8-8c52-80d56b63342c","order_by":5,"name":"Zhenyi Wang","email":"","orcid":"","institution":"Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Affiliated to Shanghai University of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Zhenyi","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2024-10-20 05:08:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5296816/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5296816/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":68654994,"identity":"b765e0bc-a67e-4495-a499-6de183a6141d","added_by":"auto","created_at":"2024-11-10 14:00:20","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":314615,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSchematic diagram of laser ablation\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5296816/v1/b1749f60b7460643e31c341b.jpg"},{"id":69639057,"identity":"3dae540f-ad2b-406a-bf4b-50e82dacd503","added_by":"auto","created_at":"2024-11-22 13:39:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":850272,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5296816/v1/ba160037-3c5c-4c2f-bb38-c57f68fa3ccb.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Long-term outcomes of Fistula Laser Closure (FiLaC ® ) with a 1470 nm diode laser for cryptoglandular anal fistula","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003eAnal fistula is a pathological passage located in close proximity to anal canal and rectum. It is typically caused by an infection of the anal gland. Anal fistula has become a common clinical disease and the incidence rate has increased to 18.4 cases per 100,000 population [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. At present, this disease cannot be cured by drugs and can only be treated by surgery. The incidence rate is higher in males than in females. We usually use Park\u0026rsquo;s classification to define different types of anal fistulas which contains the following four types: inter⁃sphincteric fistula, trans⁃sphincteric fistula, supra⁃sphincteric fistula, extra⁃sphincteric fistula. Among them, the inter⁃sphincteric and trans⁃sphincteric types are the most common ones. In the past, surgeons have used traditional technologies to treat this disease, such as fistulotomy, fistulectomy, seton placement therapy and so on. However, in recent years, surgeons are adopting new technologies to overcome the low recurrence rate and the high incontinence rate caused by traditional techniques. In order to maintain a high cure rate, the traditional methods would damage the function of the anal sphincters. Consequently, one of the major research focuses is how to protect anal sphincter function while removing fistula. Researches have shown that new technologies, such as ligation of the inter-sphincteric fistula tract (LIFT) [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], endoanal advancement flap (ERAF) [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], video assisted anal fistula treatment (VAAFT) [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], and others, have significantly reduced the risk of anal incontinence. On the other hand, the new ones have certain drawbacks, such as low cure rates (less than 50%) [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Although it is difficult to increase the cure rate, the fistula laser closure (FiLaC\u0026reg;) for anal fistula, which has emerged in recent years, has shown a better clinical effect. FiLaC\u0026reg; was originally proposed by Wilhelm in 2011 [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. By using a guidewire to quickly heat and vaporize the epithelial surfaces of fistula, the fistula can be treated. And research has also shown that the cure rate of this technique is higher than other novel techniques (71\u0026ndash;82%) [\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eTherefore, we want to observe the efficacy and safety of FilaC\u003cb\u003e\u0026reg;\u003c/b\u003e in treating inter⁃sphincteric and trans⁃sphincteric fistulas.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e"},{"header":"2 Materials and methods","content":"\u003cp\u003eExperimental design and test objects\u003c/p\u003e \u003cp\u003eWe conducted a prospective study using a prospective cohort which included 52 patients with cryptoglandular anal fistula between September 2017 and December 2019. The clinical trial was granted by the Chinese Clinical Trial Registry (No. ChiCTR-IOR-17012085). Ethical approval was granted by the ethics committee of Yueyang Hospital of Integrated Traditional Chinese and Western Medicine affiliated to Shanghai University of Traditional Chinese Medicine (No. 2017-033). Written informed consent was obtained from each participant. All procedures were carried out in accordance with relevant guidelines and regulations.\u003c/p\u003e \u003cp\u003e Inclusion criteria: (1) Those who meet the diagnostic criteria for anal fistula in the 2016 American Association of Colorectal Surgeons' Clinical Diagnosis and Treatment Guidelines for Perianal Abscess, Anal Fistula, and Rectovaginal Fistula. (2) Those who have been indicated to have an inter⁃sphincteric or trans⁃sphincteric fistula by perianal magnetic resonance imaging. (3) Those with obvious fibrotic anal fistula. (4) Age range: 18\u0026ndash;65 years.\u003c/p\u003e \u003cp\u003eExclusion criteria: (1) Patients with perianal abscess. (2) Patients with concomitant colorectal malignancy, intestinal tuberculosis, or vaginal fistula. (3) Patients with coagulation dysfunction. (4) Patients with chronic diseases such as hypertension and diabetes. (5) Individuals during menstruation, pregnancy, or lactation.\u003c/p\u003e \u003cp\u003eInterventions\u003c/p\u003e \u003cp\u003eAll patients received a preoperative intestinal preparation and underwent hair removal on the evening before the surgical procedure, which was performed using the FiLaC \u0026reg; technique. We used Leonardo DUAL 45 laser equipment (Biolitec AG, Germany) with fixed power (12W) and fixed wavelength (1470 nm). Firstly, we inserted a 360\u003csup\u003e\u0026deg;\u003c/sup\u003e dual ring diode laser fiber from the external opening to the internal opening. Then the fiber was pulled out at a constant speed of 1 mm/s while allowing the fiber to continuously release energy. At last, the external opening was removed in a suitable manner for postoperative drainage, based on the size of the incision. (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eResult evaluation\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1.1 Primary and secondary results\u003c/h2\u003e \u003cp\u003eThe primary outcomes included the 1-month cure rate, the 1-year cure rate, the 5-year cure rate, Visual Analog Scale Pain Score (VAS-PS) and Cleveland Clinic Florida Incontinence Score (CCF-IS) [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. The healing criterion was postoperative wound healing (without local redness, swelling, heat, pain, or pus discharge). Postoperative pain was measured using an 11-point Visual Analog Scale Pain Score (VAS-PS). The severity of fecal incontinence symptoms was evaluated using the Cleveland Clinic Florida Incontinence Score (CCF-IS).\u003c/p\u003e \u003cp\u003eThe secondary outcomes included the Quality of Life in Patients with Anal Fistula Questionnaire score (QoLAF-QS) [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], Bristol Stool Chart and postoperative complications. The Quality of Life in Patients with Anal Fistula Questionnaire score (QoLAF-QS) was used to assess the quality of life of patients with anal fistula. Stool consistency was assessed using the 7-point Bristol Stool Scale [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cdiv id=\"Sec4\" class=\"Section3\"\u003e \u003ch2\u003e2.1.2 Demographic data, perioperative data, and observation indicators\u003c/h2\u003e \u003cp\u003eWe collected baseline demographic data including sex, age, duration of disease, body mass index (BMI), internal and external opening positions, Parks\u0026rsquo; classification, fistula diameter, and internal opening height (the distance from the internal opening to the anal edge). Additionally, we also collected perioperative data including American Society of Anesthesiologists score, burning energy, burning time, postoperative fluid properties, and postoperative complications. Furthermore, we collected observation indicators including the primary and secondary outcomes.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section3\"\u003e \u003ch2\u003e2.1.3 Follow-up methods\u003c/h2\u003e \u003cp\u003eData was collected through outpatient follow-up for 1 month, 1 year, and 5 years after surgery. The data pertaining to the observation indicators was collected on the 1st, 3rd, 7th, 30th and 90th days postoperatively, and at 1-, 5-year intervals thereafter.\u003c/p\u003e \u003cp\u003eData Analysis\u003c/p\u003e \u003cp\u003eStatistical analysis was performed using SPSS Statistics 25.0 software (IBM Inc., IL, USA). Continuous variables were presented as either the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD) or the median with interquartile range (IQR) based on the distribution. The independent t-test was used to compare normally distributed continuous variables, whereas the Mann-Whitney U test was used to compare non-normally distributed continuous variables. Categorical data were expressed as the number of cases and percentages. A value of p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was deemed to indicate a statistically significant difference.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"3 Results","content":"\u003cp\u003eDemographic data\u003c/p\u003e \u003cp\u003eThe differences in sex, age, course of disease, BMI, Parks\u0026rsquo; classification, fistula diameter, and internal opening height between the two groups were not statistically significant (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05) and were comparable. The results are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of patient demographics and characteristics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLaser group (n\u0026thinsp;=\u0026thinsp;52)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex, n (%)\u003c/p\u003e \u003cp\u003eMale\u003c/p\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e41 (78.8)\u003c/p\u003e \u003cp\u003e11 (21.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, y [M (\u003cem\u003eP\u003c/em\u003e\u003csub\u003e25\u003c/sub\u003e, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e75\u003c/sub\u003e)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e38.7 (31,44)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDisease course, m [M (\u003cem\u003eP\u003c/em\u003e\u003csub\u003e25,\u003c/sub\u003e \u003cem\u003eP\u003c/em\u003e\u003csub\u003e75\u003c/sub\u003e)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8.23 (1.5,12)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody mass index, kg/m\u003csup\u003e2\u003c/sup\u003e [M (\u003cem\u003eP\u003c/em\u003e\u003csub\u003e25\u003c/sub\u003e, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e75\u003c/sub\u003e)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e24.6 (22.6,26.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThe position of internal opening\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFront type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6 (11.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBilateral type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e32 (61.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePosterior type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14 (26.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThe status of internal opening\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClosed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e22 (42.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOpened\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e30 (57.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParks\u0026rsquo; classification, n (%)\u003c/p\u003e \u003cp\u003eInter-sphincteric fistula\u003c/p\u003e \u003cp\u003eTrans-sphincteric fistula\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (23.1)\u003c/p\u003e \u003cp\u003e40 (76.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFistula diameter, cm [M (\u003cem\u003eP\u003c/em\u003e\u003csub\u003e25\u003c/sub\u003e, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e75\u003c/sub\u003e)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3.2(2.8,4.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInternal opening height, cm [M (\u003cem\u003eP\u003c/em\u003e\u003csub\u003e25\u003c/sub\u003e, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e75\u003c/sub\u003e)]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e33.0(27.5,38.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe statistical significance of Parks\u0026rsquo; classification was found to differ between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.00). The differences in ASA scores and suspension procedure between the two groups were not statistically significant (both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). The differences in the treatment methods of the internal opening and fistula between the two groups were statistically significant (both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.000). The results are shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of patient perioperative data\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLaser group (n\u0026thinsp;=\u0026thinsp;52)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eASA score\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eⅠ\u003c/p\u003e \u003cp\u003eⅡ\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e52 (98.1)\u003c/p\u003e \u003cp\u003e1 (1.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThe treatment of internal opening\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSuture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14 (26.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIncision\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8 (15.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSuture combined with incision\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2 (3.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e28 (53.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThe treatment of anal fistula\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIncision\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9 (17.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExcision\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1 (1.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLaser ablation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e42 (80.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThe hanging of anal fistula\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVirtual thread-hanging\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2 (3.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eShallow thread-hanging\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1 (1.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBoth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0 (0.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e49 (94.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"2\"\u003e\u003csup\u003ea\u003c/sup\u003eASA score: American Society of Anesthesiologists Score\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003ePrimary and Secondary Results\u003c/p\u003e \u003cp\u003eThe cure rates at 1month, 1 year, and 5 years were 96.2% (50/52), 82.7% (43/52), and 76.9% (40/52), respectively. The difference among internal-opening-position subgroups was statistically significant (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.018), and the cure rate of the bilateral type was higher than the anterior and posterior types(86.2%, 75% and 37.5%, respectively). The results are shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of outcomes between patients with different types of Parks\u0026rsquo; classification\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOutcomes\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInter-sphincteric fistula\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eTrans-sphincteric fistula\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eStatistical value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLaser group, n (%)\u003c/p\u003e \u003cp\u003eCure\u003c/p\u003e \u003cp\u003eRelapse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (75.0)\u003c/p\u003e \u003cp\u003e3 (25.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28 (75.7)\u003c/p\u003e \u003cp\u003e9 (24.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eX\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.962\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThere was no statistically significant difference between the subgroups: the Parks\u0026rsquo; classification, number of internal openings, closure of internal openings, treatment of internal openings, number of external openings, relative position of internal and external openings, presence of straight fistula and presence of blind fistula. The results are shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of outcomes among patients with different positions of internal opening\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOutcomes\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFront type\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBilateral type\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePosterior type\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eStatistical value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLaser group, n (%)\u003c/p\u003e \u003cp\u003eCure\u003c/p\u003e \u003cp\u003eRelapse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (37.5)\u003c/p\u003e \u003cp\u003e5 (62.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25 (86.2)\u003c/p\u003e \u003cp\u003e4 (13.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9 (75.0)\u003c/p\u003e \u003cp\u003e3 (25.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eX\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;8.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.018\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003e\u003csup\u003ea\u003c/sup\u003eThe position of internal opening\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAll the scores (VAS-PS, CCF-IS, and QoLAF-QS) increased gradually over time and subsequently decreased. The results are shown in Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of perioperative scores. (Score, x\u0026thinsp;\u0026plusmn;\u0026thinsp;s)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLaser group (n\u0026thinsp;=\u0026thinsp;52)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVAS⁃PS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePRD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.8\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 1-year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 5-year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.1\u0026thinsp;\u0026plusmn;\u0026thinsp;0.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCCF⁃IS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePRD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.0\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.4\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e1.4\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.8\u0026thinsp;\u0026plusmn;\u0026thinsp;1.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 1-year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 5-year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eQoLAF⁃QS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePRD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e17.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e21.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e19.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e17.7\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e18.3\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e17.6\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 1-year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e16.1\u0026thinsp;\u0026plusmn;\u0026thinsp;1.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePOD 5-year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e15.8\u0026thinsp;\u0026plusmn;\u0026thinsp;2.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"2\"\u003eAbbreviations: PRD\u0026thinsp;=\u0026thinsp;preoperative day; POD\u0026thinsp;=\u0026thinsp;postoperative day; CCF-IS\u0026thinsp;=\u0026thinsp;Cleveland Clinic Florida incontinence score; VAS-PS\u0026thinsp;=\u0026thinsp;Visual Analog Scale pain score; QoLAF-QS\u0026thinsp;=\u0026thinsp;Quality of Life in Patients with Anal Fistula Questionnaire score.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of laser data in various literature.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStudy\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePatients\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEnergy, watts\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003esuccess rate(%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWihelm (2011)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e81.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGiamundo (2013)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10\u0026ndash;13(980nm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e71.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026Ocirc;zturk (2014)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e82.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGiamundo (2015)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e71.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWilhelm (2017)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e64.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTerzi (2017)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e103\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e40.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLauretta (2018)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e33.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBrabender (2019)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10\u0026ndash;14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e22.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBonnechose(2020)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e44.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSluckin(2022)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e162\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e55.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLara Blanco Teres (2024)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e55.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCurrent study\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e77.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eEfficacy assessment\u003c/p\u003e \u003cp\u003eAfter 76.5 (59\u0026ndash;84) months of follow-up with FiLaC\u0026reg;, clinical healing was observed in 40 patients (76.9%), while unhealed or recurrent fistulas were observed in 12 patients (23.1%) during the follow-up period. Among the 12 patients with fistula recurrence, 5 patients had fistulas that reappeared at the surgical site, while the other 7 patients had fistulas that reappeared at other surgical sites. Of the 5 patients 8 were cured.\u003c/p\u003e"},{"header":"4 Discussion","content":"\u003cp\u003eThe main difficulty in treating anal fistula is the balance between the removal of lesions and the preservation of anal sphincters. The FiLaC\u0026reg; technique is a new sphincter-saving surgery that achieves the purpose of treatment by closing the anal fistula after ablation. It was found that the primary cure rate of the modified FiLaC\u0026reg; technique (combined with ERAF) was 64.1%, and the secondary cure rate was 88%. Giamundo conducted a retrospective analysis of 180 patients who underwent the FiLaC\u0026reg; procedure. The results showed that the cure rates of the primary operation and the second operation were 66.8% and 73.7%, respectively. Other studies have shown that the cure rates of FiLaC\u0026reg; technique rang from 22\u0026ndash;82% [\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. There is no established consensus regarding the optimal type of surgery and indications for the FiLaC\u0026reg; technique. The studies are shown in Table\u0026nbsp;7.\u003c/p\u003e \u003cp\u003eTo avoid recurrence, fistulotomy is usually performed by making an incision along the anal fistula using an electric scalpel. This allows for adequate visualization of the foci and adequate dressing changes of the inflamed tissues. This causes significant damage to the anal sphincter, leading to postoperative pain and sphincter dysfunction. To make up for the defects of traditional surgery, the FiLaC\u0026reg; technique uses a guidewire to quickly heat and vaporize the epithelial surfaces of fistulas.\u003c/p\u003e \u003cp\u003eThe following reasons may contribute to the low cure rate of laser group.\u003c/p\u003e \u003cp\u003e(1) The FiLaC\u0026reg; technique treats the internal opening with laser ablation, which causes the internal opening to shrink and local protein denaturation. During postoperative tissue healing, feces may infect the unhealed wound, leading to the recurrence of anal fistula. This hypothesis is also consistent with the findings of Giamundo et al. [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] and Wilhelm et al. who suggested that the treatment of the internal opening is particularly important for postoperative healing of anal fistula.\u003c/p\u003e \u003cp\u003e(2) In terms of fistula management, the FiLaC\u0026reg; technique makes it impossible to continue coking the inflammatory tissue below the coking layer after the surface tissue has been charred. Therefore, there is still room for localization of inflammation in fistulas with severe inflammation infiltration or complex shapes. Researches have shown that laser fistulectomy is more suitable for simple fistulas less than 30 millimeters. The fiber diameter is 1.8mm and the laser penetration depth is 2 to 3mm. It is not possible to directly observe the internal situation of the fistula during surgery. If the diameter of the fistula is too large, the laser will not completely burn the epithelial tissue of the tube wall, making it difficult to evenly ablate the fistula. If the diameter of the fistula is too small, the superficial tissues and skin are more likely to be damaged during burning than in traditional fistula resection surgery, where the situation of fistula resection can directly observed. In addition, the laser catheter is more suitable for straight fistulas because the tip of the catheter is not tough enough to bend. In contrast, it increases the difficulty of the operation in curved or branched fistulas [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Therefore, in the laser closure of anal fistula, the selection of laser energy should be adapted to the position and wall thickness of the fistula, and the optimal parameters should be chosen as the core of laser treatment for anal fistula [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. In addition, the results of this study showed that there was no statistically significant difference in the cure rate of anal fistula between the two. The sample size of patients with sphincter-type anal fistula may be small, and further large-scale clinical studies are needed to confirm this.\u003c/p\u003e \u003cp\u003eWe also recognize that there are certain limitations of this study. Firstly, this study is a prospective analysis with a limited number of cases, and all included patients have Parks I and II anal fistulas. Therefore, further large-scale prospective experimental studies are needed to clarify its optimal indications. Secondly, in terms of the treatment of the internal opening, we can optimize the following plan: (1) for patients with a large and fibrotic internal opening, internal opening resection should be performed before laser closure; (2) if the internal opening is small and not fibrotic, laser closure should be used and then the internal opening sutured with 3\u0026thinsp;\u0026minus;\u0026thinsp;0 Vico suture; (3) patients with non-fibrotic and pseudo-closed internal opening were treated with laser closure alone.\u003c/p\u003e \u003cp\u003eIn conclusion, the FiLaC\u0026reg; technique is suitable for cryptoglandular anal fistula with an internal opening located on both sides or behind the anal canal. It can significantly reduce postoperative pain, lower the rate of anal incontinence and improve patients' postoperative quality of life. However, considering that this study is only a single center retrospective study, prospective bulk case studies can be conducted in the future.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCCF-IS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eCleveland Clinic Florida Incontinence Score\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eERAF\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eEndoanal Advancement Flap\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eFiLaC\u0026reg;\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eFistula Laser Closure\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eLIFT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ethe Inter-sphincteric Fistula Tract\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eQoLAF-QS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ethe Quality of Life in Patients with Anal Fistula Questionnaire score\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eVAAFT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eVideo Assisted Anal Fistula Treatment\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eVAS-PS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eVisual Analog Scale pain score.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eJingyi Zhu and Zhicheng Li wrote the main manuscript text and Jingyi Zhu prepared figures 1. All authors reviewed the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eThis work was supported by the Science and Technology Commission of Shanghai Municipality (Grant No. 20Y21901200) (to J.W.), a grant from the National Natural Science Foundation of China (Grant No. 82274531) (to Z.W.).\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e \u003cp\u003eThe data sets generated and analysed in this study are not publicly available due to the sensitive data regulations of our institutional policy, but a de-identified data could be available from the first author (Dr. JY Zhu) upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eMazier WP. The treatment and care of anal fistulas: a study of 1,000 patients. 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Bristol Stool Chart: \u0026eacute;tude prospective et monocentrique de \u0026laquo; l'introspection f\u0026eacute;cale \u0026raquo; chez des sujets volontaires [Bristol Stool Chart: Prospective and monocentric study of \"stools introspection\" in healthy subjects]. Prog Urol. 2014;24(11):708\u0026ndash;713. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.purol.2014.06.008\u003c/span\u003e\u003cspan address=\"10.1016/j.purol.2014.06.008\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMarref I, Spindler L, Aubert M, et al. The optimal indication for FiLaC\u0026reg; is high trans-sphincteric fistula-in-ano: a prospective cohort of 69 consecutive patients. 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Implementation of laser ablation of fistula tract (LAFT) for perianal fistulas: do the results warrant continued application of this technique?. Tech Coloproctol. 2019;23(12):1127\u0026ndash;1132. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s10151-019-02112-9\u003c/span\u003e\u003cspan address=\"10.1007/s10151-019-02112-9\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGiamundo P, Esercizio L, Geraci M, Tibaldi L, Valente M. Fistula-tract Laser Closure (FiLaC\u0026trade;): long-term results and new operative strategies. Tech Coloproctol. 2015;19(8):449\u0026ndash;453. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s10151-015-1282-9\u003c/span\u003e\u003cspan address=\"10.1007/s10151-015-1282-9\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIsik O, Gulcu B, Ozturk E. Long-term Outcomes of Laser Ablation of Fistula Tract for Fistula-in-Ano: A Considerable Option in Sphincter Preservation. Dis Colon Rectum. 2020;63(6):831\u0026ndash;836. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/DCR.0000000000001628\u003c/span\u003e\u003cspan address=\"10.1097/DCR.0000000000001628\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChand M, Tozer P, Cohen RC. Is FiLaC the answer for more complex perianal fistula?. Tech Coloproctol. 2017;21(4):253\u0026ndash;255. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s10151-017-1621-0\u003c/span\u003e\u003cspan address=\"10.1007/s10151-017-1621-0\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Fistula Laser Closure, 1470 nm diode laser, cryptoglandular anal fistula, long-term outcomes","lastPublishedDoi":"10.21203/rs.3.rs-5296816/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5296816/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e \u003cp\u003eThe aim of this study was to evaluate the long-term efficacy of Fistula Laser Closure (FiLaC\u0026reg;)with using a 1470 nm diode laser in the treatment of cryptoglandular anal fistula.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eData of patients with cryptoglandular anal fistula who underwent FiLaC\u0026reg; in our department between September 2017 and December 2019 were retrospectively analyzed. Demographic data, perioperative data and postoperative data were collected and statistically analyzed.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eA total of 52 patients who met the inclusion criteria were included in the study. The cure rates at 1month, 1 year, and 5 years were 96.2% (50/52), 82.7% (43/52), and 76.9% (40/52), respectively. The differences among the internal opening position subgroups were statistically significant (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.018), with the bilateral type having a higher cure rate than the anterior and posterior types (86.2%, 75% and 37.5%, respectively). No statistically significant differences were observed between the subgroups: Parks classification, number of internal openings, closure of internal openings, treatment of internal openings, number of external openings, relative position of internal and external openings, presence of straight fistula, and presence of blind fistula. All the scores, including visual analogue scale pain score (VAS-PS), cleveland clinic florida incontinence score (CCF-IS), and the quality of life in patients with anal fistula questionnaire score (QoLAF-QS), showed a gradual increase over time, followed by a subsequent decrease.\u003c/p\u003e\u003ch2\u003eDiscussion\u003c/h2\u003e \u003cp\u003eAlthough the cure rate of the FiLaC\u0026reg; technique is inferior to that of traditional surgery, the FiLaC\u0026reg; technique has significant advantages in reducing the postoperative pain, the risk of fecal incontinence, and the postoperative quality of life. Furthermore, the FiLaC\u0026reg; technique is more suitable for cryptoglandular anal fistulas with an internal opening located on both sides or behind the anal canal. This study provides a preliminary evaluation of the FiLaC\u0026reg; technique, and we hope to increase the cure rate in the future by observing improvements in surgical methods, laser burning power, laser burning time and other aspects.\u003c/p\u003e","manuscriptTitle":"Long-term outcomes of Fistula Laser Closure (FiLaC ® ) with a 1470 nm diode laser for cryptoglandular anal fistula","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-11-10 14:00:15","doi":"10.21203/rs.3.rs-5296816/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"673c6c85-5705-41ed-bcfe-b74a656f64fb","owner":[],"postedDate":"November 10th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-11-22T13:39:04+00:00","versionOfRecord":[],"versionCreatedAt":"2024-11-10 14:00:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5296816","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5296816","identity":"rs-5296816","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}