Long-term clinical, radiological, and histological follow-up after complex ventral incisional hernia repair using urinary bladder matrix graft reinforcement: a retrospective cohort study.

BACKGROUND: Complex ventral incisional hernia repair represents a challenging clinical condition in which biologically derived graft reinforcement is often utilized, but little long-term data inform that decision. Urinary bladder matrix (UBM) has shown effectiveness in diverse clinical settings as durable reinforcement graft material, but it has not been studied over a long term in ventral incisional hernia repair. This study evaluates the clinical, radiographic, and histological outcome of complex incisional hernia repair using UBM reinforcement with 12-70 months of follow-up.

METHODS: A single-arm, retrospective observational study of all ventral incisional hernia repairs utilizing UBM reinforcement over a 6-year time frame by a single surgeon was performed. Patients were assessed in long-term follow-up clinically and with the Carolina Comfort Scale. A subset of patients was assessed with abdominal wall ultrasound or CT scan. Three patients had abdominal wall fascial biopsies years after the incisional hernia repair with UBM graft, and the histology is analyzed.

RESULTS: 64 patients underwent repair of complex incisional hernias with UBM graft reinforcement by a single surgeon. 42 patients had concomitant procedures including large or small bowel resection, excision of infected mesh, evacuation of abscess or hematoma, cholecystectomy, or panniculectomy with abdominoplasty. 16 patients had ostomies at the time of repair. Median follow-up time is 36 months, with a range of 12-70 months. Nine patients (14%) have required surgical repair of a recurrent hernia, and a tenth patient has a recurrence that is managed non-surgically, for a total recurrence rate of 15.6% over the entire time frame. Median time to recurrence was 32 months, and a Kaplan-Meier freedom from recurrence curve is depicted. 28 patients have undergone ultrasound or CT assessments of the abdominal wall which demonstrate radiographic fascial integrity 12-70 months after repair. Three patients have been re-explored for unrelated reasons in the years following ventral incisional hernia repair with UBM, and full thickness fascial biopsies demonstrate a robust remodeling response histologically similar to native myofascial tissue. No patients have developed graft infection, fistulization to the graft, or required graft explantation. Carolina Comfort Scale assessment of 45 patients 3 years after the repair averaged 16 out of a possible 115.

CONCLUSION: In 64 patients undergoing complex ventral incisional hernia repair with UBM reinforcement, all have experienced successful resolution of complex clinical conditions and 15.6% of these repairs have recurred at a median follow-up of 3 years. Three full-thickness biopsies of the repaired fascia years later shed light on a promising remodeling response which may signal strength and durability comparable to native fascia.