A new 3D imaging tool for fistulas

What this research is looking at

Around 1 in 3 people with Crohn’s will likely develop a fistula at some point. A fistula is a narrow tunnel or passage that links one organ to another. Perianal fistulas are the most common type of fistula. Perianal fistulas connect the anal canal or rectum to the surface of the skin near the anus where poo leaves the body. They often occur following an abscess around the anus. An abscess is a painful collection of pus usually caused by infection.

Fistulas may be managed with medicines, surgery, or a combination of both. As many as 1 in 3 people with Crohn’s who have an anal fistula will need to have surgery to treat their fistula. The goal of surgery is to heal the fistula while avoiding damage to the anal sphincter muscles. These muscles surround the anus and control the release of poo.

People with a perianal fistula are usually referred to see a surgeon. They will have an MRI scan and an examination under anaesthesia (while asleep). This allows any abscesses to be drained and a seton to be placed. A seton is a soft surgical thread that is tied through the fistula and allows the pus and infected tissue to drain away.

Abscesses or fistulas can be difficult to identify during an examination under anaesthesia. This can lead to ongoing infections and a need for further surgeries. This causes scarring and delays the medical treatment after surgery that allows fistulas to heal. Multiple or incorrectly performed surgeries can also damage the anal sphincter muscles, leading to bowel incontinence.

Dr Evans believes that improving how information about the fistula is communicated between those reporting MRI scans and the surgeon is critical – it will improve how surgeons find and treat fistulas during surgery. It’s difficult for surgeons to interpret a complex written description of a 3D structure and to use that as their guide to fistula surgery.

Advances in digital technology allow fistulas and the surrounding body structures to be seen in 3D. This technology is called Virtual Examination Under Anaesthesia (vEUA). vEUA allows the surgeon to better understand the anatomy of and around the fistula, alongside the usual MRI report.

This research project will investigate whether vEUA increases confidence and ability of surgeons in identifying and treating fistulas. The researchers will also see whether using vEUA improves the quality of life of people having surgery to treat a perianal fistula.

What the researchers think this could mean for people with Crohn's

vEUA will give surgeons more information to help plan and perform surgery, so that all fistulas and abscesses are properly treated. The confidence of the surgeon and their team in treating perianal fistulas will increase, leading to better patient outcomes. People with Crohn’s will benefit from fewer surgeries, a quicker start on medicines used after surgery and fewer complications.

Surgical times and costs will reduce, as there will be fewer follow on surgeries, saving the NHS money.

In addition, vEUA will allow a patient to see a 3D model of their fistula. This will help them better understand the plans for their surgery and to see how things have improved after treatment. This will allow people with Crohn’s to make more informed decisions about their care.

Who is leading this research: Dr Jonathon Evans, Nottingham University Hospital NHS Trust

Our Funding: £44,261

Duration: 24 months 

Official title of application: A feasibility study to assess a "Virtual" (vEUA) Technology to improve the management of perianal Crohn’s disease