Low-Dose Pre-Operative Botulinum Toxin A Effectively Facilitates Complex Ventral Hernia Repair: A Case Report and Review of the Literature.

Background: Complex ventral hernias following laparotomy present a unique challenge in that repair is hindered by the lateral tension of the abdominal wall. A novel approach to overcome this is the "chemical component separation" technique. Here, botulinum toxin A (BTA) is instilled into the muscles of the abdominal wall. This induces flaccid paralysis and effectively reduces tension in the wall, allowing the muscles to be successfully joined in the midline during surgery. We describe a method where a large incisional hernia was repaired using this technique and review the variations in methodology. Case report: A woman in her mid-40s developed a ventral hernia in the setting of a previous laparotomy for a small bowel perforation. Computed tomography (CT) of the abdomen demonstrated an 85 (Width) × 95 mm (Length) ventral hernia containing loops of the bowel. Pre-operative botulinum toxin A administration was arranged at the local interventional radiology department. A total of 100 units of BTA were instilled at four sites into the muscular layers of the abdominal wall under CT-fluoroscopic guidance. She underwent an open incisional hernia repair 4 weeks later, where the contents were reduced and the abdominal wall layers were successfully joined in the midline. There was no clinical evidence of hernia recurrence at 3-months follow-up. Conclusion: Low-dose BTA effectively facilitates the surgical management of large ventral incisional hernias. There is, however, significant variation in the dosage, concentration and anatomical landmarks in which BTA is administered as described in the literature. Further studies are needed to assess and optimise these variables.