Effect of Preoperative Botulinum Toxin on the Outcome of Large Midline Hernia Repair

Abdominal hernias with large fascial defects are very difficult to repair, and it is almost impossible to achieve midline closure without causing abdominal compartment syndrome or intra-abdominal hypertension. Preoperative botulinum toxin A (BTA) infiltration into the lateral abdominal wall muscles has been shown to facilitate fascial closure in such cases.

This prospective interventional study was conducted from October 2023 to April 2025 in adult patients aged ≥ 18 years with large midline abdominal wall hernias with a defect width of more than 10 cm. Preoperative computed tomography (CT) was used to measure transverse defect width, lateral abdominal wall muscle length, and Tanaka index. A total dose of 300 IU of BTA (Botox) was administered under ultrasound-guided (USG) guidance into the external oblique, internal oblique, and transversus abdominis muscles bilaterally according to the Ibarra-Hurtado technique. A repeat CT along with volumetry was performed 4 weeks after BTA administration. Surgical repair was done by posterior component separation with transversus abdominis release, and in some cases a peritoneal flap was utilized to achieve midline closure.

Twenty-four patients (8 males and 16 females) with a mean age of 54.1 ± 10.8 years were included. A significant reduction in the transverse hernia defect was observed from 17.8 ± 4.8 cm to 12.2 ± 3.9 cm (p < 0.001). Significant elongation of lateral abdominal wall muscles on both sides and reduction in the Tanaka index were also observed (p < 0.001). A defect width of more than 18 cm with a mean defect of 21.7 ± 3.2 cm required an additional peritoneal flap to achieve midline closure.

In abdominal wall reconstruction, preoperative BTA is safe and effective in facilitating large midline abdominal wall hernia repair. Very large defects may require additional peritoneal flaps despite BTA administration and component separation techniques.