Bioabsorbable synthetic plug in the treatment of anal fistulas

Surgical management of complex perianal fistula revisited in a systematic review: a critical view of available scientific evidence

BACKGROUND

Treating complex perianal fistulas in Crohn's disease patients remains a challenge. Classical surgical treatments for Crohn's disease fistulas have been extrapolated from cryptoglandular fistulas treatment, which have different etiology, and this might interfere with its effectiveness, in addition, they increase fecal incontinence risk. Recently, new surgical techniques with support from biological approaches, like stem cells, have been developed to preserve the function of the sphincter. We have performed a systematic literature review to compare the results of these different techniques in the treatment of Crohn's or Cryptoglandular fistula.

METHODS

PubMed, EMBASE, Database of Abstracts of Reviews of Effectiveness, Cochrane Central Register of Controlled Trials were searched systematically for relevant articles. We included randomized controlled trials and observational studies that referred to humans, were written in English, included adults 18+ years old, and were published during the 10-year period from 2/01/2010 to 2/29/2020. Evidence level was assigned as designated by the Scottish Intercollegiate Guidelines Network.

RESULTS

Of the 577 citations screened, a total of 79 were ultimately included in our review. In Crohn's disease patients, classical techniques such as primarily seton, Ligation of Intersphincteric Fistula Tracks, or lay open, healing rates were approximately 50-60%, while in cryptoglandular fistula were around, 70-80% for setons or flaps. In Crohn's disease patients, new surgical techniques using derivatives of adipose tissue reported healing rates exceeding 70%, stem cells-treated patients achieved higher combined remission versus controls (56.3% vs 38.6%, p = 0.010), mesenchymal cells reported a healing rate of 80% at week 12. In patients with cryptoglandular fistulas, a healing rate of 70% using derivatives of adipose tissue or platelets was achieved, and a healing rate of 80% was achieved using laser technology. Fecal incontinence was improved after the use of autologous platelet growth factors and Nitinol Clips.

CONCLUSION

New surgical techniques showed better healing rates in Crohn's disease patients than classical techniques, which have better results in cryptoglandular fistula than in Crohn's disease. Healing rates for complex cryptoglandular fistulas were similar between the classic and new techniques, being the new techniques less invasive; the incontinence rate improved with the current techniques.

Minimally Invasive Treatment of Recurrent Anal Fistulas with Autologous Platelet-Rich Plasma Combined With Internal Orifice Closure

AIM

Minimally invasive procedures for the treatment of anal fistulas are gaining more and more popularity. For this purpose, Platelet-Rich Plasma (PRP) are administered to accelerate the healing process of various difficult wounds or lesions. The aim of this study was to evaluate preliminary results of PRP injection into the tissues adjacent to anal fistulas.

PATIENTS AND METHODS

A cohort of 42 patients with recurrent anal fistula, who underwent at least one cutting procedure previously, were enrolled into this preliminary and prospective trial. Closure of internal orifice was performed in all investigated patients, however, in 22 patients from group I, that procedure was combined with topical injection of PRP. In the postoperative period, the PRP administration could be repeated in case of incomplete fistula closure. Follow-up consisted of out-patient visits in a fortnight, 1, 2, and 12 months.

RESULTS

Complete closure of anal fistulas was achieved in 16 (75%) patients from group I and 10 (45,5%) patients from group II. The fistulas were healed in 9 patients from group I after single application of PRP. In the next 9 patients with incomplete fistula closure, the injection was repeated 2 to 4 times every fortnight leading finally to complete recovery in 6 of them.

CONCLUSIONS

Surgical fistula closure with local PRP application spares the anal sphincter and gives the opportunity to repeat the procedure several times if necessary. Treatment of recurrent anal fistulas with PRP can be considered as last resort therapy.

Heterogeneity in outcome selection, definition and measurement in studies assessing the treatment of cryptoglandular anal fistula: findings from a systematic review

Background

Treatment for cryptoglandular anal fistula (AF) is challenging and a lack of uniform outcomes in the literature prevents direct comparison of treatments. This can be addressed by developing a core outcome set, a standardised set of outcomes reported in all interventional studies for a specific condition. The aim of this systematic review is to assess the range of outcomes, their definitions, and the measurement instruments currently utilised in interventional studies for adult patients with AF. This will inform the development of an AF core outcome set.

Methods

Medline, Embase and The Cochrane Library were searched to identify all patient- and clinician-reported outcomes in studies assessing medical, surgical or combination treatment of adult patients with AF published from January 2008 to May 2020. The resulting outcomes were categorized according to the Core Outcome Measurement in Effectiveness Trials (COMET) taxonomy to better understand their distribution.

Results

In total, 155 studies were included, 552 outcomes were extracted, with a median of three outcomes (interquartile range 2–5) per study. Only 25% of studies demonstrated high-quality outcome reporting. The outcomes were merged into 52 unique outcomes and structured into four core areas and 14 domains, with the majority in the domain of physiological or clinical (gastrointestinal) outcomes. The most commonly reported outcomes were healing (77%), incontinence (63%), and recurrence (40%), with no single outcome assessed across all studies. There was a wide variation in outcome definitions and measurement instruments used.

Conclusions

There is substantial heterogeneity in outcomes, definitions, and measurement instruments reported in interventional studies for cryptoglandular anal fistula. This emphasises the need for standardised outcome reporting and measurement.

Long-Term Clinical Results of Use of an Anal Fistula Plug for Treatment of Low Trans-Sphincteric Anal Fistulas

BACKGROUND An anal fistula plug is a sphincter-sparing procedure that uses biological substances to close an anorectal fistula. This study aimed to evaluate the long-term therapeutic effect of an anal fistula plug procedure in patients with trans-sphincteric fistula-in-ano and to determine the risk factors affecting fistula healing. MATERIAL AND METHODS A single-center retrospective study was performed assessing long-term treatment outcomes of patients with low trans-sphincteric anal fistulas who initially underwent anal fistula plug procedures between August 2008 and September 2012. Risk factors affecting fistula healing were identified using univariate and multivariate analyses. RESULTS A total of 135 patients who had low trans-sphincteric anal fistulas and underwent anal fistula plug procedures were analysed. The overall healing rate was 56% (75/135) with a median follow-up time of 8 years (range, 72-121 months). The primary reasons for treatment failure were plug extrusion (n=12, 20%) and surgical site infection (n=9, 15%), occurring within 30 days after surgery. Multiple logistic regression analysis showed that the duration of anal fistula ≥6 months was significantly associated with treatment failure using an anal fistula plug (OR=3.187, 95% CI: 1.361-7.466, P=0.008). Of the patients who failed initial treatment with an anal fistula plug, 6 (9%) had anal fistulas that healed spontaneously after 2-3 years without additional treatment. CONCLUSIONS As a sphincter-preserving procedure, the anal fistula plug can effectively promote healing of low trans-sphincteric anal fistulas. The long-term efficacy is good and the procedure warrants wider use in clinical practice.

Effects of an anal fistula plug on anal function after surgery for treatment of a trans-sphincteric anal fistula

PURPOSE

The aim of this study was to evaluate the anal function in patients with trans-sphincteric anal fistulas who underwent an anal fistula plug procedure, and analyze risk factors that might affect post-operative anal function.

METHODS

This was an observational, retrospective study of patients diagnosed with trans-sphincteric anal fistulas and initially underwent anal fistula plug procedures between August 2008 and September 2012 at our institute. The analysis includes clinical characteristics, anal fistula healing, and the Wexner score for pre- and post-operative anal function (0 = no incontinence to 20 = complete incontinence).

RESULTS

A total of 123 patients who had an adequate follow-up in the end were included. The median duration of follow-up was 8 years (range 72-121 months). The overall healing rate was 56% (69/123), and 33 (26.8%) patients had decreased anal function after surgery. The post-operative Wexner score on anal function was significantly higher than that before the operation (p < 0.001), as well as scores of gas, liquid stool, solid stool incontinence, and alteration in lifestyle (p < 0.05). Based on multiple logistic regression analysis, a high body mass index (p < 0.001) and long distance between the external opening and anal verge (p = 0.003) were significantly associated with a decline in post-operative anal function.

CONCLUSIONS

As a sphincter-preserving technique for the treatment of anal fistulas, the anal fistula plug procedure might impair the anal function. Especially for patients with obesity or long distance between the external opening of anal fistula and anal verge, the reduced anal function is more likely to occur after treatment with anal fistula plug therapy.

Contemporary surgical practice in the management of anal fistula: results from an international survey

Background

Management of anal fistula (AF) remains challenging with many controversies. The purpose of this study was to explore current surgical practice in the management of AF with a focus on technical variations among surgeons.

Methods

An online survey was conducted by inviting all surgeons and physicians on the membership directory of European Society of Coloproctology and American Society of Colon and Rectal Surgeons. An invitation was extended to others via social media. The survey had 74 questions exploring diagnostic and surgical techniques.

Results

In March 2018, 3572 physicians on membership directory were invited to take part in the study 510 of whom (14%) responded to the survey. Of these respondents, 492 (96%) were surgeons. Respondents were mostly colorectal surgeons (84%) at consultant level (84%), age ≥ 40 years (64%), practicing in academic (53%) or teaching (30%) hospitals, from the USA (36%) and Europe (34%). About 80% considered fistulotomy as the gold standard treatment for simple fistulas. Endorectal advancement flap was performed using partial- (42%) or full-thickness (44%) flaps. Up to 38% of surgeons performed ligation of the intersphincteric fistula tract (LIFT) sometimes with technical variations. Geographic and demographic differences were found in both the diagnostic and therapeutic approaches to AF. Declared rates of recurrence and fecal incontinence with these techniques were variable and did not correlate with surgeons’ experience. Only 1–4% of surgeons were confident in performing the most novel sphincter-preserving techniques in patients with Crohn’s disease.

Conclusions

Profound technical variations exist in surgical management of AF, making it difficult to reproduce and compare treatment outcomes among different centers.

Electronic supplementary material

The online version of this article (10.1007/s10151-019-02051-5) contains supplementary material, which is available to authorized users.

Japanese Practice Guidelines for Anal Disorders II. Anal fistula

Anal fistulas usually result from an anal gland infection in the intersphincteric space, which is caused by bacteria entering through the anal crypt (cryoptglandular infection). Reports of anal fistulas have been as high as 21 people in 100,000. Anal fistulas are 2-6 times more prevalent in males than females, with the condition occurring most frequently in patients in their 30s and 40s. Anal abscess symptoms include sudden onset of anal pain, swelling, redness, and fever. Purulent discharge or intermittent perianal swelling and pain are most often consistent with anal fistula symptoms. Methods for diagnosing anal fistulas include visual inspection, palpation, digital examination, anoscopic examination, barium enema, fistulography, as well as imaging, such as ultrasound, CT, and MRI. Parks classification is widely adapted in the West; however, Japan usually employs Sumikoshi classification. Antibiotics should be administered in cases of perianal abscess with surrounding cellulitis, or concomitant systemic disease, or those not alleviated by incision and drainage. The site and size of incision and drainage depend upon the abscess type and location. Incisions should be performed taking care not to damage the sphincter muscles and with possible future fistula surgery in mind. As spontaneous recovery is rare, except in the case of children, surgery is the principle approach to anal fistulas. Several approaches are utilized for anal fistulas. A specific procedure may be chosen depending upon curability and anal function. Postsurgical outcomes vary from study to study. Fecal incontinence may occur after fistula surgery, but reports vary.

A novel model of acellular dermal matrix plug for anal fistula treatment. Report of a case and surgical consideration based on first utility in Poland

Anal fistula (AF) is a pathological connection between anus and skin in its surroundings. The main reason for the formation of anal fistula is a bacterial infection of the glands within the anal crypts. One of the modern techniques for the treatment of fistulas that do not interfere with the sphincters consists in implantation of a plug made from collagen material. We are presenting the first Polish experience with a new model of biomaterial plug for the treatment of anal fistula. We also point out key elements of the procedure (both preoperative and intraoperative) associated with this method. In the authors' opinion, the method is simple, safe and reproducible. Innovative shape of the plug minimizes the risk of its migration and rotation. It also perfectly blends with and adapts to the course and shape of the fistula canal, allowing it to become incorporated and overgrown with tissue in the fistula canal. The relatively short operation time, minor postoperative pain and faster convalescence are with no doubt additional advantages of the method. Long-term observation involving more patients is essential for evaluation of the efficacy of the treatment of fistulas with the new type of plug.

Prospective evaluation of a new device for the treatment of anal fistulas

AIM: To evaluate the safety of the implantation of a new device for the treatment of anal fistulas. The short-term clinical efficacy was also assessed.

METHODS: This study took place at a tertiary care university hospital. Patients with a complex anal fistula of cryptoglandular origin were enrolled in the study and were treated with insertion of the new device. All patients were evaluated by clinical and physical examination, including an endoanal ultrasound at the baseline, and then at the 2 wk and 1, 2, 3 and 6-mo follow-up visits.

RESULTS: Morbidity, continence status, and success rate were the main outcome measures. Ten patients underwent the placement of the new device. The fistulas were transphincteric in eight patients and extrasphincteric in the remaining two. The median duration of the surgical procedure was 34.5 (range, 27-42) min. Neither intra- nor postoperative complications occurred, and all patients were discharged the day after the procedure. At the 6-mo follow-up evaluation, the final success rate was 70%. Three failures were registered: a device expulsion (on the 10^th postoperative day), the persistence of inflammatory tissue around the fistula tract (at the 2-mo follow up), and the persistence of serum discharge (at the 6-mo follow up). No patient experienced any change incontinence, as assessed by the Cleveland Clinic Fecal Incontinence score.

CONCLUSION: The technical procedure is simple and has low risk of perioperative morbidity. The pre- and post-operative continence status did not change in any of the patients. The initial results at the 6-mo follow up seem to be promising. However, a longer follow-up period and a larger sample size are needed to confirm these preliminary results.

Management of Complex Anal Fistulas

Complex anal fistulas require careful evaluation. Prior to any attempts at definitive repair, the anatomy must be well defined and the sepsis resolved. Several muscle-sparing approaches to anal fistula are appropriate, and are often catered to the patient based on their presentation and previous repairs. Emerging technologies show promise for fistula repair, but lack long-term data.

Delayed absorbable synthetic plug (GORE® BIO-A®) for the treatment of fistula-in-ano: a systematic review

AIM

Recent advances in the treatment of fistula-in-ano have focused on surgical techniques that preserve sphincter integrity. Plugs that obliterate the lumen of the fistula track have been proposed as one such method, and may be derived from biological or delayed absorbable synthetic materials. Biological plugs have highly variable results and have not been widely adopted. The aim of this systematic review was to assess the effectiveness and safety of a delayed absorbable synthetic plug (GORE® BIO-A®) for treatment of anal fistula.

METHOD

A systematic review of all literature in the English language relevant to the use of a plug to treat anal fistula and published between 1 January 2008 and 15 February 2015 was carried out by searching MEDLINE, EMBASE and the Cochrane Library of Systematic Reviews/Controlled Trials for relevant literature. Relevant articles were identified, quality assessed using the methodological index for nonrandomized studies criteria and data were extracted by two independent researchers (SKN and NNA). The identified articles were assessed with regard to fistula healing rate, duration of follow-up and complication rates related to the use of delayed absorbable synthetic fistula plugs.

RESULTS

Twenty six potential articles were identified from the literature search. Using the predefined inclusion and exclusion criteria, six were included in the final analysis, data extraction and data synthesis. Of these included in the review only three were prospective in design. Complete data were available for 187 of the 221 patients who underwent this treatment. The age of the participants ranged from 19 to 82 years. The fistula healing rates were reported to be between 15.8% and 72.7% at a follow-up ranging between 2 and 19 months. Early or delayed plug extrusion occurred in 16 (8.5%) of the 187 patients. Deterioration in continence was reported in 11 (5.8%) of 187 patients.

CONCLUSION

There are insufficient high-quality data on the delayed absorbable synthetic (GORE® BIO-A®) fistula plug to draw meaningful conclusions regarding its effectiveness. It does, however, appear to be a simple and safe technique associated with low complication rates and a minor deterioration in continence in a few cases.

Treatment of Fistula-In-Ano with Fistula Plug - a Review Under Special Consideration of the Technique

Introduction

In a recent Cochrane review, the authors concluded that there is an urgent need for well-powered, well-conducted randomized controlled trials comparing various modes of treatment of fistula-in-ano. Ten randomized controlled trials were available for analyses: There were no significant differences in recurrence rates or incontinence rates in any of the studied comparisons. The following article reviews the studies available for treatment of fistula-in-ano with a fistula plug with special attention paid to the technique.

Material and Methods

PubMed, Medline, Embase, and the Cochrane medical database were searched up to July 2015. Sixty-four articles were relevant for this review.

Results

Healing rates of 50–60% can be expected for treatment of complex anal fistula with a fistula plug, with a plug-extrusion rate of 10–20%. Such results can be achieved not only with plugs made of porcine intestinal submucosa but also those made of other biological or synthetic bioabsorbable mesh materials. Important technical steps are firm suturing of the head of the plug in the primary opening and wide drainage of the secondary opening.

Discussion

Treatment of a complex fistula-in-ano with a fistula plug is an option with a success rate of 50–60% with low complication rate. Further improvements in technique and better studies are needed.

Evaluation and management of perianal abscess and anal fistula: a consensus statement developed by the Italian Society of Colorectal Surgery (SICCR)

Perianal sepsis is a common condition ranging from acute abscess to chronic fistula formation. In most cases, the source is considered to be a non-specific cryptoglandular infection starting from the intersphincteric space. The key to successful treatment is the eradication of the primary track. As surgery may lead to a disturbance of continence, several sphincter-preserving techniques have been developed. This consensus statement examines the pertinent literature and provides evidence-based recommendations to improve individualized management of patients.

Prospective multicenter study of a synthetic bioabsorbable anal fistula plug to treat cryptoglandular transsphincteric anal fistulas

BACKGROUND

Although interest in sphincter-sparing treatments for anal fistulas is increasing, few large prospective studies of these approaches have been conducted.

OBJECTIVE

The study assessed outcomes after implantation of a synthetic bioabsorbable anal fistula plug.

DESIGN

A prospective, multicenter investigation was performed.

SETTING

The study was conducted at 11 colon and rectal centers.

PATIENTS

Ninety-three patients (71 men; mean age, 47 years) with complex cryptoglandular transsphincteric anal fistulas were enrolled. Exclusion criteria included Crohn's disease, an active infection, a multitract fistula, and an immunocompromised status.

INTERVENTION

Draining setons were used at the surgeon's discretion. Patients had follow-up evaluations at 1, 3, 6, and 12 months postoperatively.

MAIN OUTCOME MEASURES

The primary end point was healing of the fistula, defined as drainage cessation plus closure of the external opening, at 6 and 12 months. Secondary end points were fecal continence, duration of drainage from the fistula, pain, and adverse events during follow-up.

RESULTS

Thirteen patients were lost to follow-up and 21 were withdrawn, primarily to undergo an alternative treatment. The fistula healing rates at 6 and 12 months were 41% (95% CI, 30%-52%; total n = 74) and 49% (95% CI, 38%-61%; total n = 73). Half the patients in whom a previous treatment failed had healing. By 6 months, the mean Wexner score had improved significantly (p = 0.0003). By 12 months, 93% of patients had no or minimal pain. Adverse events included 11 infections/abscesses, 2 new fistulas, and 8 total and 5 partial plug extrusions. The fistula healed in 3 patients with a partial extrusion.

LIMITATIONS

The study was nonrandomized and had relatively high rates of loss to follow-up.

CONCLUSION

Implantation of a synthetic bioabsorbable fistula plug is a reasonably efficacious treatment for complex transsphincteric anal fistulas, especially given the simplicity and low morbidity of the procedure.

Biomaterials in the treatment of anal fistula: hope or hype?

Anal fistula (AF) presents a chronic problem for patients and colorectal surgeons alike. Surgical treatment may result in impairment of continence and long-term risk of recurrence. Treatment options for AFs vary according to their location and complexity. The ideal approach should result in low recurrence rates and minimal impact on continence. New technical approaches involving biologically derived products such as biological mesh, fibrin glue, fistula plug, and stem cells have been applied in the treatment of AF to improve outcomes and decrease recurrence rates and the risk of fecal incontinence. In this review, we will highlight the current evidence and describe our personal experience with these novel approaches.

A technical modification of video-assisted ablation for recurrent pilonidal sinus

AIM

The study evaluated, in a proof of concept, the usefulness of a prosthesis (plug) in addition to video assisted ablation of pilonidal sinus (VAAPS) for treatment of recurrent pilonidal sinus.

METHOD

This is a case series of recurrent complex pilonidal sinus treated by VAAPS plus plug positioning.

RESULTS

Four patients were analysed. All were successfully treated by this new approach. No difficulties in inserting the plug were identified. Complete healing was achieved in all cases. No infection or recurrence was reported during a limited follow-up.

CONCLUSION

This new technique allows a minimally invasive scarless approach to recurrent pilonidal sinus.