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Updated: Jun 15, 2025

Laparoscopic Repair of Para-Esophageal Hernia Using Absorbable Biosynthetic Mesh
Published on: September 11, 2021
Parastomal Hernia Prevention Using Funnel-Shaped Intra-Abdominal Mesh Compared to No Mesh: The Chimney Randomized
Elisa Mäkäräinen1, Heikki Wiik1, Maziar Nikberg2
1Oulu University Hospital, Medical Research Center Oulu, Oulu, Finland.
Importance:
Prophylactic placement of a mesh has been suggested to prevent parastomal hernia. Evidence to support this practice is contradictory.
Objective:
To determine whether funnel-shaped permanent synthetic parastomal mesh is effective and safe in parastomal hernia prevention.
Design, Setting, And Participants:
The Chimney Trial was a randomized single-blinded multicenter trial conducted in 4 hospitals in Finland and 1 in Sweden from February 2019 and September 2021. Of 439 patients with rectal adenocarcinoma undergoing either laparoscopic or robotic-assisted abdominoperineal resection or the Hartmann procedure, 143 were enrolled in the trial, 135 received their allocated intervention, and 121 were analyzed at 12-month follow-up. Data were analyzed from December 2023 to May 2024.
Intervention:
In the intervention group, a permanent colostomy was created with a funnel-shaped intraperitoneal mesh and compared to a control group with a stoma without the mesh.
Main Outcome And Measure:
The primary end point was the incidence of computed tomography (CT)-confirmed parastomal hernia 12 months after surgery.
Results:
There were 68 patients (mean [SD] age, 68.7 [11.6] years; 36 [53% male and 32 [47%] female) who received the intended allocation in the mesh group and 67 (mean [SD] age, 66.4 [11.7] years; 48 [72%] male and 19 [28%] female) who received the intended allocation in the control group. CT scans were available for 58 patients in the mesh group and 59 patients in the control group at the 12-month follow-up. CT scans confirmed parastomal hernia in 6 of 58 patients (10%) in the mesh group compared to 22 of 59 patients (37%) in the control group (difference, 27%; 95% CI, 12-41; P < .001). Clinical parastomal hernia as a secondary outcome was recorded in 1 of 60 patients (2%) in the mesh group compared to 27 of 61 (43%) in the control group (difference, 41%; 95% CI, 29-55; P < .001). The number of patients with Clavien-Dindo class II ileus was 23 (35%) in the mesh group compared to 11 (17%) in the control group (difference, 18%; 95% CI, 3-32; P = .006). Only slight differences between the groups were detected in other stoma-related complications, readmissions, operative time, surgical site infections, reoperations, and quality of life.
Conclusions And Relevance:
In this study, funnel-shaped parastomal mesh prevented a significant number of parastomal hernias without predisposing patients to mesh- or stoma-related complications during 12-month follow-up. The results of this study suggest the funnel-shaped mesh is a feasible option to prevent parastomal hernia.
Trial Registration:
ClinicalTrials.gov Identifier: NCT03799939.

