The skin under our eyes is very thin and an extremely delicate area. As we age, we start by losing collagen, fat, bone from our under eyes all of which leads to hollowness and an aging face. The hollowness, as a result of lack of volume, is the primary reason people seek out dermal fillers for the tear trough area. Dark circles are usually a genetic factor from skin pigmentation most often seen in Middle Eastern, Hispanic ad dark skinned descents.  Dark circles underneath the eyes could also be due to poor lifestyle choices such as improper sleep, dehydration and exhaustion. It is important to be able to distinguish who is a candidate for under eye filler to avoid complications such as misplaced filler or a puffy under eye result. The solution may not always be filler, as surgery  could be the better alternative in some cases. If there is excess skin above or below the eyes, or puffy eyebags then under eye dermal filler may not be the optimal choice. However, if the undereye appears to be hollow from sudden weight loss or early signs of aging with out the heavy eyebags, then the non-invasive dermal filler injections using a microcannula will be an appropriate solution.