As we age the facial skeleton changes and we loose soft tissue volume in terms of fat.
One of the changes that occurs is that we loose bone in particular is the orbit where the eyeball sits. In addition the fat that sits above the eye is lost. This can result in a hollow appearance to te upper eye region.
In some patients that have undergone upper eyelid surgery where excessive fat has been removed can have a similar hollow appearance. In this instance, this is referred to as an A frame deformity.
This hollowness can be very effectively treated with volume replacement with a dermal filler such as Juvederm Volbella.