An anal fistula is an abnormal connection between the anal canal or rectum and the skin around the anus. Although it may initially seem like a simple problem, some fistulas have complex pathways and cross a significant portion of the muscles responsible for bowel control.
In these situations, treatment requires a careful balance: eliminating the fistula while protecting the anal sphincter and preserving continence.
This is where minimally invasive, sphincter-preserving techniques have become increasingly important.
What does “minimally invasive” mean in anal fistula treatment?
In general, these procedures aim to treat the fistula tract and close its internal opening while minimizing damage to the anal sphincter.
Several techniques are currently available, including:
- VAAFT (Video-Assisted Anal Fistula Treatment) – uses a small camera, called a fistuloscope, to visualize the inside of the fistula tract. This allows the surgeon to identify and treat the tract and close its internal opening.
- FiLaC (Fistula Laser Closure) – uses a laser fiber placed inside the fistula tract. Controlled laser energy is delivered along the tract to promote closure while avoiding a large incision through the sphincter.
- OTSC (Over-the-Scope Clip) – uses a specially designed clip to mechanically close the internal opening of the fistula.
- Biological plugs and scaffolds – use specialized materials that can provide a framework for tissue healing and fistula closure.
- Cell-based therapies – use cells with regenerative and immunomodulatory properties and have been particularly investigated for fistulas associated with Crohn’s disease.
Although these techniques differ considerably, they share an important goal: preserving the anal sphincter whenever possible.
Does minimally invasive mean better?
Not necessarily.
This is an important point for patients considering treatment for an anal fistula.
Minimally invasive techniques are promising and may be excellent options for carefully selected patients. However, the available studies differ substantially in terms of fistula anatomy, patient characteristics, follow-up duration, and technical approach.
Therefore, there is currently no single minimally invasive technique that is considered the best treatment for every anal fistula.
Treatment selection depends on several factors, including:
- the location of the fistula;
- how much of the sphincter is involved;
- the presence of secondary branches;
- the location of the internal opening;
- whether an abscess is present;
- previous fistula treatments;
- whether Crohn’s disease is present;
- and the individual characteristics of the patient.
In other words, the treatment should be tailored to the fistula — not simply chosen from a list of available technologies.
What about stem cell therapy?
Among the newer approaches, mesenchymal stem cell therapy is one of the most interesting areas of current research.
These cells may have regenerative, anti-inflammatory, and immunomodulatory properties. This is particularly relevant in perianal fistulas associated with Crohn’s disease, where inflammation plays an important role in the persistence of the disease.
The available evidence is promising however, there is the substantial variability between studies and the need for more standardized treatment protocols.
Therefore, stem cell therapy should not be presented as a universal or guaranteed cure. Its potential role depends on appropriate patient selection and fistula characteristics.
Technology matters. Appropriate indication matters even more.
Complex anal fistulas require careful assessment and planning.
Before choosing a treatment, it is important to understand the exact anatomy of the fistula. In selected cases, pelvic MRI can help identify the main tract, secondary branches, abscesses, and its relationship with the anal sphincter.
After this assessment, different approaches may be considered — from established surgical procedures to sphincter-preserving and minimally invasive techniques.
The goal is not simply to “close the hole.”
The goal is to treat the underlying fistula, minimize the risk of recurrence, preserve continence, and protect quality of life.
Anal fistula treatment is not a one-size-fits-all procedure
Every fistula has its own anatomy. The most appropriate treatment therefore depends on the characteristics of the fistula, previous treatments, associated conditions, and the patient’s individual goals and risks.
If you have an anal fistula — particularly if you have already undergone previous treatments or have Crohn’s disease — a specialist evaluation can help determine which treatment options are appropriate for your specific situation.
The first step toward choosing the right treatment is understanding exactly what type of fistula you have.