I had Belotero injected for Eye trough 3 months ago, initially looked improved

Hi HS.  It's hard to say without photos what has happened, but technique may be an issue.  We inject Restylane (we like this better than Belotero) deep under the muscle and this lifts the whole plane of the under eye area.  If the product is placed near the surface of the skin in the delicate tissue directly below the eye, it can end up looking more like baggy fluid.  To see examples of Los Angeles before and after pictures for Restylane injections under the eyes, click the link below.

Belotero is a great filler for under eyes.  It typically lasts over a year. What you probably noticed is the swelling going away after 2 to 3 weeks, meaning you could probably use more filler.  Best to discuss with your physician and/or see an oculoplastic specialist. Sometimes, lower blepharoplasty may be the better option.

I have found it to last a year or longer in most patients, but it is a "softer" filler that can be more easily pushed around than some of the other fillers (Juvederm).  It is possible that rubbing of your eyes or the way you sleep may have effected its longevity.  There can also be some initial swelling from the filler injection that can be helpful in terms of appearance cosmetically that has since resolved. I have found it to give a nice smooth appearance that lasts a long time.  The other fillers may be used in this area, but they have higher risk of producing a bluish discoloration on the skin surface.  Depending upon your anatomy and goals, surgery may be a better option for you.  Best regards.