Hi Eliza,
The tear trough deformity is usually caused by descent of cheek fat, thereby causing a hollowing below the lower eyelid in comparison to the cheek fullness. This is something that usually gets worse as people age and becomes more noticeable if the lower eyelids begin to show signs of aging with fat herniation. When a prominent tear trough develops at your young age, there is usually a genetic component to the occurrence as well.
It is difficult to give you a complete recommendation about permanent correction without a full face photograph and an in-person consultation. Options to rejuvenate this area in younger patients generally revolve around fillers. Injectable fillers like Restylane and Juvederm are easily obtained by your surgeon off the shelf and they can last 6 months or more. Fat injection into this area is a potentially permanent solution, although this requires you to get a small amount of liposuction and possibly multiple treatment sessions to get the right amount of fat to survive where needed. Unfortunately, non of these options will stop the aging process long term. You should seek consultation with a plastic surgeon if you would like to consider these options further.
I hope that this helps!
Jeremy White, MD