Is lipo both under and above chin muscle at the same time riskier?

It is safer to liposuction the superficial fat and not the subplatysmal fat.  In addition, it is probably best to avoid laser liposuction in this area since the skin is thin and the risk of irregularities or burns greater.  Standard or power assisted lipo is usually recommended. 

Thanks for writing,There classically is fat above and or below the platysma muscle. Liposuction above the muscle works very well in the right patient. Typically sub-platsymal fat is removed under direct vision through a small incision, because there is a lot of anatomy there and an injury is not good. You did not include any photos, so further suggestions / comments can not be made except for the above general statements. You may wants to get a second opinion. Now you have more data and information to ask great questions. Good LuckStephen M. Davis, MD, FACSGreen Hills Plastic SurgeryCertified: American Board of Plastic SurgeryMember: American Society for Aesthetics Plastic SurgeryMember: American Society of Plastic Surgery

You are correct, fatty deposits are located above and below the  platysma muscle in the neck. Liposuction is required to remove the fatty deposits above the platysma muscle. A surgical neck lift is required to remove that a compartment of fat underneath muscle which also includes a platysma-plasty. As long as you're less than 50 years of age, no skin removal is required. For many before-and-after examples, please see the link and the video below