A Pilot Study on the Use of Injection Lipolysis in Visceral Adipose Tissues

Abstract

Intraperitoneal fat, also known as visceral adipose tissue (VAT), poses significant metabolic risks. Reduction of this fat is functionally and aesthetically desirable. Since surgical reduction has serious risks, a noninvasive method for reduction of this fat would have important clinical benefits. The authors evaluate the reduction in VAT in an animal model using injection lipolysis. Phosphatidylcholine was injected in half of the omentum of 16 dogs (weight 30-40 kg) by surgical laparotomy. The dogs' vital signs were followed postoperatively. A second laparotomy was performed at 2 weeks (n = 10), 4 weeks (n = 4), or 6 weeks (n = 2). Reduction of fat in the injected side was assessed by comparing with the control side. Specimens of the injected and the control sides were examined microscopically. Intraperitoneal cultures were also obtained. There was a major reduction in the amount of fat in all 16 dogs. No intraperitoneal abscesses, collections, or adhesions developed, and there was no injury to any intra-abdominal organs. Microscopic examination showed significant fat loss and lysis of fat cells with cellular infiltrate formed of predominantly macrophages, with fibrosis developing in the 6-week specimens. No bacterial or fungal growth was observed on the cultures. The dogs' vital signs showed no significant variation from the preoperative baseline. Injection lipolysis is effective and safe in reducing VAT in dogs. Further studies are needed to prove its efficacy and safety in humans and refine its indications and method of injection.