Why don’t doctors aspirate with dermal filler?

When filler is placed into the skin and layers below, the best way to minimize accidentally placing filler into a blood vessel is not by aspirating the syringe but by;1. low pressure injection. This means as little pressure applied to the plunger of the syringe needed to have the filler come out of the syringe2. Depositing small amounts with each needle placement. 

Thank you for the great question. The bottom line is that each injector has his or her own preference when injecting. Aspiration can sometimes be a good idea but by no means will it prevent any and all complications. The best thing you can do is have a safe and experienced injector who knows the anatomy. And furthermore one that knows and is prepared to deal with complications when they happen!Best of luck!Dallas R. Buchanan, MD, FACSOwner & Board-Certified Plastic SurgeonVIVIFY plastic surgery

Each Doctors technique will vary. If you have questions about the procedure that was performed, I recommend following up with your injector. It will take 1-2 weeks for your final results. Best, Dr. Emer

Although aspiration while doing fillers is commonly done for safety reasons, studies have shown that a good portion of the time even aspiration doesn’t insure safety. 

I agree with what so many others have said about aspirating not being totally reliable and foolproof. One thing that has not been said  is that some filers are very east to aspirate with and some are nearly impossible. I tend to use my fillers that I can easily aspirate(sculptra) most liberally in areas that I am more concerned with occlusion because I know whether I am in vessel and I am more restricted when using those that can not aspirate well. 

The use of aspiration depends on individual physician preference, technique, and type of filler being used. Studies have shown that aspiration alone can lead to a false sense of safety. Slow, lower pressure injections using small amounts of product performed by an experienced injector with good understanding of facial vascular anatomy will result in the safest filler injection experience. 

Thanks for your question. Once the needle or cannula has dermal filler in it aspiration is completely unreliable as a "safety measure". Some still demonstrate it as a "show" but the fact is it is quite useless. There are other technique ex we use to reduce risk, such as avoiding known danger zones, constantly moving the top while injecting, being at the proper depth on a region. Etc.. that keep the incidence of vascular occlusion very rare. 
Best,
Lisa Vuich. MD