Feasibility Study to Assess the Early Use of Porcine Cross-linked Collagen Paste in Cryptoglandular Anorectal Fistulas

Study Overview
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Brief Summary
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This study is designed to assess the effectiveness of porcine cross-linked collagen paste for the treatment of patients with ano-rectal abscess with underlying cryptoglandular fistula in ano.

Detailed Description
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Most anal fistulae are thought to arise as a result of the infection of anal glands. This infection frequently presents as an anorectal abscess which requires drainage of the abscess under a general anaesthetic. Abscess and fistula should be considered as the acute and chronic phase of the same anorectal infection.The abscess represents the acute inflammatory event, whereas the fistula is representative of the chronic process. At the time of drainage of the anorectal abscess, the underlying fistulas frequently go undetected. As a result, patients present with a fistula in ano several months later. In this study, the investigators aim to identify the underlying fistula in patients with a perianal abscess with the help of an MRI Scan done in the acute setting. Participants with a confirmed fistula on the MRI scan have their abscess treated as per convention. However, a repeat examination under anaesthetic is performed 7-'10 days later when the fistula tract is identified and treated with injection of the porcine collagen paste into the fistula tract. Participants are followed up clinically and radiologically to assess the effectiveness of the intervention.

Official Title
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Feasibility Study to Assess the Early Use of Porcine Cross-linked Collagen Paste in Cryptoglandular Anorectal Fistulas

Conditions
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Anorectal Abscess, Fistula in Ano

Intervention / Treatment
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* Biological: Collagen paste


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: o Clinical diagnosis of Cryptoglandular fistula in ano. Exclusion Criteria: Insulin dependent diabetes Thyroid disease Fistula secondary to Crohn's disease/Ulcerative Colitis Clinical or radiological evidence of secondary tracts. Complex fistula tracts on MRI scan such as Horseshoe fistula, anorectal-vaginal fistula Patients refusing informed consent for admission to the study. Previous fistulotomy/fistulectomy Pregnancy Patients unable to consent Patients not suitable for MRI scan those with- Cochlear implant, Permanent pacemaker, Implanted metal work, Aneurysm clips, Claustrophobia, Metallic foreign body

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Collagen paste<br>Injection of Permacol Collagen paste into the fistula tract. | Biological: Collagen paste<br>* Permacol cross-linked collagen paste, 2.5-3.5 mls to be injected into the MRI defined fistula tracts 7-10 days following drainage of the anorectal abscess.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fistula Healing rate at 3 months | Healing of fistula as evidenced by MRI of the ano-rectum. | 3 months | 
| Fistula Healing Rate at 12 months | This will be assessed by a telephonic questionnaire at 12 months following intervention | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Complication rate | Any complications resulting from participation in the the trial will be assessed on clinical and telephonic follow up. Clavien and Dindo Classification will be used to assess the severity of complications. | 12 months | 
| Faecal Incontinence questionnaire (Wexner) | To assess any adverse impact of intervention on continence | At recruitment, 7-10 days, 6 weeks and 6 months | 
| Faecal Incontinence quality of life questionnaire (FIQL) | To assess the impact on the quality of life of the participants | At recruitment, 7-10 days, 6 weeks and 6 months | 
| Pain Score | Visual analogue score | At recruitment, 7-10 days, 6 weeks and 6 months |