What Happens when Liquefied Fat is Not Suctioned Out?

It is best to remove the liquified fat after laser assisted liposuction. Leaving the devitalized fat behind runs the risk of fat necrosis and the development of lumps and bumps. While your body would likely resorb most of the fat, it is not a good idea to take a chance.
David Shafer, MD
New York City

I first want to clarify that tumescent Smart Lipo is the same thing as Smart Lipo. Tumescent fluid is the fluid we use to anesthetize the tissue to allow liposuction of any type, whether it's Vaser Liposelection (Ultrasonic Assisted Liposuction), standard suction assisted liposuction, or Smart Lipo (laser assisted liposuction). By using the laser, the fat is essentially melted and then we suction out the treated fat with a suction device. If treated fat is left behind, the body will clear it out on its own. These damaged fat is seen as devitalized tissue which the body sends out scavenger cells to clean up the "mess." Sometimes, when treating a very thin patient's body, I will use the laser to treat the fat and may not suction as much to prevent potential contour irregularities. This is especially useful in a thin patient's abdomen or inner thighs. Over time the tightening improves as does the contour. Hope this helps!!

The unsuctioned liquified fat will be broken down by inflammatory cells and be disposed of by the body without any likely real health concern. But this is an interesting question and there is no study I am aware of looking at this with regard to risks or results. It do feel it is important to suction the liqueurs fat though for many reasons, and feel that not removing it can contribute to a less than perfect result. Much of the results of lipo depend not only on the removal or destruction of the fat tissue but by how the skin redrapes. It is my feeling that leaving unsuctioned fat there will likely affect perfect redraping of then skin and contribute to irregularities and possibly suboptimal skin tightening.

I definitely believe that in most cases suctioning the fat out after Smartlipo achieves much better results.  Only in cases where very minor contouring is performed do I consider not performing suctioning of the fat with Smartlipo.

If all of the fat is not absorbed, your body absorbs the fat naturally. This is with reasonable amounts of course. 

Laser or ultrasound assisted liposuction causes fat cell destruction.  The fat cells are composed of a lipid bilayer and the lipids are metabolized and removed from the body.  This means that it will take additional time for you to see the final result.

Dead tissue left behind from surgery is generally eaten up by the body by macrophages or walled off as a granuloma (firm permanent lump). The process of removal of this tissue involves inflammation. The mediators of inflammation cause pain and lumpiness ( temporary and sometimes permanent) and scarring, and prolong the healing (and therefore recovery) process.
While it is true that scarring can cause tightening of the tissue, the process of scarring can also cause contracture, or undesireable scarring. This in turn can cause limitation in motion and tethering of the skin, dimpling and irregularities. The formation of these problems is not predictable.
It is better not to leave dead tissue behind during surgery. This in my opinion includes leaving behind emulsified fat without doing liposuction to "clean up" the emulsified fat.

Liposuction techniques like ultrasonic or laser transmit energy to the fat to liquefy it. Once this fat is liquefied the body treats it as something to get rid of. If it is not removed then it becomes the body's job to get rid of it.
Now it is impossible to remove every last bit of devitalized fat with liposuction (or any other technique) and the body is quite good at "cleaning up" small volumes of devitalized tissue spread throughout a wide area. The problem could come if there were collections of devitalized fat. This could lead to scar (lumps, bumps, contracture and change in shape long term) or infection (devitalized tissue is an excellent medium for bacteria).
I hope this helps.
Steven Williams, MD

It’s best to melt fat and suctioned, and has been my practice since 2005, combining SmartLipo and Tumescent Liposuction.

Smartlipo without suction, if done on an area where the volume of undesirable fat is not excessive, will simply result in gradual resorption of the fat over time, and the result should be acceptable. If a large volume has been lasered, however, the chances for inconsistency and lumpiness are greater. The best advice is to simply always suction after laser, which speeds healing, lessens inflammation, and, most importantly, gives the patient their desired result much faster.