The Effect of Botox on the Implant Stabilization and Capsular Formation: An Experimental Study

Breast augmentation is one of the most common esthetic procedures with increasing frequency throughout the past years. The most demanding complications involving esthetic and reconstructive breast surgery are the malpositioning of the implant and capsular contracture. The etiology, prevention, and management remain to be fully explained. Botulinum toxin (BTX) administration has anti-inflammatory effects that can possibly decrease capsular contracture, and chemical denervation of the pectoral muscle theoretically may decrease incidence of malrotation. In our literature search, we found only 1 clinical study using BTX A for capsular contraction, and there were no experimental studies about the implant stabilization and capsular contracture. Therefore, we have studied the effect of BTX A on the prevention of breast implant malrotation and capsular contracture in a rabbit model.

Sixteen smooth-surfaced cohesive gel implants were implanted in 8 New Zealand white rabbits. The backs of the rabbits were divided into 2 groups. After skin incision, the exposed latissimus dorsi muscle was elevated, and a submuscular pocket was made. In the experimental group, Botox was injected in the muscle overlying the implant. In the control group, the implants were placed under the muscle, and saline was injected into the muscle. At the end of 3 months, the rabbits were imaged and evaluated by ultrasonography and x-ray to examine capsule formations and the movement of the implants. The animals were killed, and the implants with peri-implant capsule were excised. We evaluated collagen pattern and capsule thickness on ventral, lateral, and dorsal aspects.

The Botox group showed less infiltration of inflammatory cells at the third month (P < 0.05). Statistically significant differences in capsular thickness were observed on histopathological examination and ultrasonographic imaging. The capsule was thinner on all aspects and the collagen pattern had a more parallel alignment at low density in the experimental group compared with the control group. With x-ray, we observed an increased lateral movement of the implants in the control group.

The use of Botox effectively decreased implant movement and capsular formation at 12 weeks. More experimental and clinical studies will be required to determine whether this is a durable result that can be reproduced in humans.