What is the cause of the lower eyelid bags?
Thank you for asking your question. The lower eyelid bags are fat. This can be caused by genetic factors and the aging process. Allergies and sinusitis do not cause bags, but can slightly increase the appearance of the bags due to swelling. This swelling can be treated with cold compresses and antihistamines, but only surgery can remove the fat. I hope this helps.
Very simple, there is no such thing as allergic shiners.
Your sinuses and allergies does not cause your under eye issues unless you chronically rub your eyes. A photograph would be invaluable to provide a more meaningful response to your question.
Can a physician diagnose the cause of under eye bags - whether it is allergic/sinus/medical or aging?
Yes, typically the cause of your eyelid bags can be diagnosed during an in-office physical examination and review of your medical history. Sometimes the patient may have an eyelid bag but the appearance worsen with seasonal allergies, increased sodium intake, etc.
The attached link provides more inforamtion.
I hope this helps