Rippled mesh: a CT sign of abdominal wall ePTFE prosthesis infection

Area of Science:

• Abdominal surgery
• Medical imaging
• Biomaterials

Background:

• Infection of expanded polytetrafluoroethylene (ePTFE) meshes used for abdominal incisional hernia repair is a rare but severe complication.
• Distinguishing infected fluid collections from non-infected seromas around ePTFE meshes is challenging, often necessitating surgical exploration.
• Prompt diagnosis is crucial as infected meshes typically require removal, unlike sterile seromas.

Observation:

• A novel imaging sign was observed in two patients undergoing abdominal computed tomography (CT) for fluid collections post-incisional hernia repair with ePTFE mesh.
• Both patients presented with fluid collections without overt signs of mesh infection.
• The observed sign involved an alteration in the mesh profile on CT imaging.

Findings:

• The identified CT sign, an altered mesh profile, was consistently associated with prosthesis infection in the observed cases.
• Surgical exploration and microbiological examination confirmed infection in both patients.
• This specific sign was absent in CT images of patients with sterile seromas.

Implications:

• The findings suggest that an altered ePTFE mesh profile on CT may indicate prosthesis infection.
• This imaging sign could potentially improve the differential diagnosis between infected and non-infected fluid collections, guiding treatment decisions.
• The proposed mechanism involves a "rejection" phenomenon where inflammatory tissue interacts with the infected prosthesis.