V45 - Novel Robotic VRAM Flap for Repair of Recurrent Colovesicular Fistula

CME Eligible

Purpose/Background: Colovesicular fistulas are a well-known complication of a variety of intraabdominal pathologies including Crohns disease, malignancy, and diverticular disease. Though conservative management of said fistulas can be offered in patients with complex comorbidities, the mainstay of treatment remains surgical excision and repair of the fistulas. Despite being a relatively successful operation, the rate of recurrence of colovesicular fistulas after repair is up to 11%. Management of recurrent fistulas has proven to be challenging and previously unreported. This case elucidates the use of a robotically harvested pedicled vertical rectus abdominis muscle (VRAM) flap as a viable option for the repair of recurrent colovesicular fistulas.

Methods/Interventions: This case report describes a 48 year old male with a history of diverticulitis and tobacco use that had previously undergone a robotic sigmoidectomy with colovesicular fistula takedown and primary bladder repair. He then re-presented to the colorectal surgery clinic with concerns for persistent UTIs. After a CT of the abdomen/pelvis confirmed the recurrence of a colovesicular fistula, the patient was scheduled for a robotic takedown of colovesicular fistula followed by rectus muscle flap harvest and pedicled graft placement.

During the operation, after resection of the affected bowel and takedown of the recurrent colovesicular fistula, the left deep inferior epigastric artery pedicle was identified. The posterior rectus sheath was incised left and laterally to the linea alba. The incision was extended superiorly to the level of the falciform. The rectus abdominis muscle was then dissected from the posterior and anterior rectus sheaths. Then, approximately 2/3 of the superior portion rectus muscle was divided in a medial to lateral fashion. The rectus muscle was then transected inferiorly towards the pedicle. The flap was then laid into the pelvis and ICG was administered revealing that the entirety of the muscle flap was well perfused. The flap was interposed, tension free, along the anterior surface of the rectum between the remaining colon and the bladder and secured with 3-0 Vicryl sutures.

Attention was turned to the donor tissue site at which the posterior sheath was closed with a running 2-0 V Loc suture. The fascia was cinched with approximately 2cm of space to the muscle to prevent incarceration and allow for flap swelling.

Results/Outcomes: By using this novel technique of robotically placing a rectus abdominis flap between the remaining sigmoid colon and the bladder, we created an autogenous barrier between the two structures thus eliminating the risk of fistula recurrence. Since the operation, there have been no complaints or evidence of pneumaturia, fecaluria, recurrent UTIs, or recurrent diverticulitis.

Conclusion/Discussion: The use of the surgical robot in the harvesting of a VRAM flap for the repair of a recurrent colovesciular fistulas has proven to be successful as seen in this case. Harvesting of rectus abdominis flaps has evolved significantly over time. Large abdominal incisions and the violation of the anterior rectus sheath has made the traditional open approach to harvest less favorable. Advancements in minimally invasive techniques have made the robotic approach a more viable option. In addition to enhanced precision, robotic surgery offers smaller fascial defects, thus decreasing the risk of abdominal hernia. Furthermore, decreased rate of infection and post operative pain have been recorded when comparing robotic approaches to traditional open harvests.