Fat embolus is a very serious and known complication of fat transfer. The probability of embolus is much higher in the setting of fat transfer than for liposuction alone. While fat embolus, has always been known to be a potential complication of liposuction, the recent rise in high profile incidents is due in part to the meteoric rise of the BBL or buttock augmentation via fat transfer. A fat embolus occurs when injected fat is inadvertently introduced into a vessel and travels centrally within the vasculature. The hallmark triad of symptoms include neurologic changes, a petechial rash, and respiratory changes. The treatment is typically supportive in nature. While it is a very serious complication, if diagnosed early it can be managed. Mortality rates are quoted as low as 5%. While it is true, injection of donor fat into the infra-muscular plane (within the muscle) increases fat viability this does come with a significant increase in risk. There are large vessels deep to and within the muscle which can be inadvertently injected while grafting leading to a fat embolus. The consequences of such a complication are very serious and life threatening. At the recent American Society of Plastic Surgeons Hot Topics, data from AAAASF (ambulatory surgical certifying body) was presented, suggesting that BBL /gluteal lipoaugmentation demonstrates a dramatically higher risk profile than other surgeries. The Aesthetic Surgery and Educational and Research Fund is convening a task force as well. The hope is that we will have more concrete guidelines for addressing these very serious complications. That being said, the safest way to avoid fat emboli is to stay in the subcutaneous plane (at the expense of fat viability)and avoid the deeper muscular plane. If grafting of the deep plane is planned, surgeons should consider blunt cannulas, aspiration prior to injection. Using a supra-gluteal approach to minimize the risk of inadvertent intravascular injection has also been proposed. Unfortunately, even when undertaking the maximal precautions, complications can occur. They can occur to any physician irrespective of training, location etc. Thus it is very important to be followed closely by your physician. This will ensure that in the unlikely event of a problem, diagnosis can be made promptly and treatment started immediately. With regards to your specific question, SmartLipo is no more or less likely to result in fat emboli than traditional liposuction. However, the risks are much smaller than when combined with fat transfer. Additionally, SmartLipo is not typically employed for BBL as the laser destroys the fat which does not produce viable graft. As always, discuss your concerns with a board certified plastic surgeon (ABPS)