Gained and lost weight, double chin - What procedure wild help with my neck? (Photos)

You seem to be good candidate for anterior neck lift; through a small incision underneath the chin, a surgeon can tighten and rearrange platysma muscle which created these strong bands. More elaborate and beneficial procedure in your case would be lower face and neck lift which will give you 10-12 years of good, stable result. Good luck.

Morpheus 8 is a non-invasive skin and soft tissue tightening treatment that is consistently amazing in our patients. We use the Morpheus to exact fractional induced RF into the skin or tissue in order to tighten collagen and stimulate contraction of the tissue. For acne scars, it is quite useful to build collagen in patients who have atrophic scars but is not very productive for ice-pick scars which require TCA Cross. For tissue tightening, Morpheus is ideal for the face and neck and we often combine it with CO2 laser or Ultherapy to further enhance results. Chemical peels and skin resurfacing should be done at least 5 to 7 days after, but can be performed earlier, depending on treatment severity. Avoid exfoliating skin treatments before Morpheus and expect a period of 2-4 weeks for skin contraction to set in.

Best,
Dr. Karamanoukian
Realself100 Surgeon

The most effective way to do this would be a facelift/necklift with facial fat grafting. The facelift allows to pull from above the mandibular (jawline) line. The neck lift allows contouring below the jawline and tightening of the neck while also addressing the platysmal bands.

From your images, you appear to be an excellent candidate for a necklift surgery, in which excess skin is removed and the underlying muscles are adjusted to redefine your jaw angle.

Chin Liposuction and Thermitight
Chin liposuction helps reduce the bulge under the chin and can be done for the whole neck. Once the fat is removed the skin can become loose and saggy in some cases. It can be avoided by combining it with Thermitight which is a radiofrequency heat delivered under the skin to tighten it. Both chin liposuction and Thermitight can be done at the same time. The recovery is fast and it can be done under local anesthesia.
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Regards
Dr. J

From the photos that you have provided it appears that you are dealing with normal aging of the neck. There may be some isolated fat but the bigger issues are the laxity of the skin and platysma muscle. Fillers and Botox have no role at all in this area. You will need a facelift surgery that addresses the platysma muscle and perhaps the fat and muscle beneath these muscles in the neck.