I have both experience with Teosyal Redensity II for the tear troughs (having you used it for years in my satellite practice abroad) and I have extensive experience in the use of hyaluronidase for dissolving unwanted filler. The short answer to your question is that hyaluronidase can be used even several years later with good results for dissolving unwanted filler, which, under the eyes, may actually last for several years (I have had a few patients whose results under the eyes lasted between three and seven years). So long as the swelling under the eyes is not from lymphatic edema, hyaluronidase injected in the appropriate amounts and concentrations should improve the condition. I have long asserted that hyaluronidase can affect normal surrounding normal tissue, as well, so it is imperative that you consult with an experienced board certified cosmetic dermatologist or other core aesthetic physician. Should this happen a small amount of hyaluronic acid filler properly injected should readily correct the problem. I am no fan of autologous fat injections. In fact, I gave up using fat injections years ago for a number of reasons. For one, it is a relatively expensive, two-step, minimally invasive technique--one wound to withdraw the fat with a large cannula from the hips, belly or buttocks, and a second procedure with a large cannula to inject it under the eyes. There is downtime associated with both procedures. And, if there are lumps or other complications, there is no enzyme to dissolve the injected fat. Perhaps at least as troubling is the fact that the injected fat retains the properties of the region from which it is taken. This means that as one ages, fat taken from the midriff region can develop a "midriff bulge" in the injected location, just as it would in its original site. Make sure you are consulting with an experienced injector. Best of luck.