My aunt wears glasses but she still has vision trouble, could an eyelid lift help? I wonder if my aunt’s drooping eyelids are starting to interfere with her ability to see clearly. She is in her 70s, but I am concerned that the procedure may cause more se

Take a look at her. There are many reasons for lowered vision which her ophthalmologist can discover. Drooping lids can interfere with vision if they fall over the lash line. Does she need to lift her head up to see, or can you see the pupil from a straight on gaze. If there is obstruction, then lifting the lids will clear the vision (try taping them up). Otherwise there is another issue.
Peripheral vision. Peripheral or upward vision can be effected by eyelids coming over the eyelashes! see a facial plastic surgeon, an ovule plastic surgeon or a general plastic surgeon for a consult and testing.
Possibly. If the droopy eyelids are interfering with her field of vision, eyelid lift , or blepharoplasty could help. It has to be documented with a vision field test done by an ophthalmologist in straight gaze . So start by taking her to an ophthalmologist who can examin her vision and assess what is causing her vision problems.
It may. Ask her ophthalmologist to do a "visual field" examination. The results will answer a number of your questions.
When . When we are discussing vision, we are referring to either 1) visual acuity - how clearly you can see the words on the page. 2) color vision - the ability to see color. Some people (mostly men) are not able to see the full color spectrum. 3) visual field - the "window" of how much you can see. Trimming the upper eyelid skin will not improve visual acuity or color vision but it can greatly improve a person's visual field. Removing sagging upper eyelid skin can be like removing blinders or a visor that blocks the upper portion of a person's vision. When performed by a competent and well-trained doctor, it is one of the safest surgeries we perform.
It . It is possible that excessive, drooping upper eyelids are blocking your aunt's vision. To find out if a blepharoplasty (or eyelid lift) would help her she should have a complete eye exam including visual field testing to see if she has a notable visual field blockage. If she does have visual field blockage that improves with taping her eyelids up temporarily then she would likely benefit from upper eyelid blepharoplasty. This procedure can be done as an office procedure with local numbning medicine only if she wanted. This allows the surgery to be quite safe and efficient, in my opinion. The key is focusing on conservative surgery so as to avoid over-resecting eyelid skin. Once she has had her eye exam a consultation with a board certified facial plastic surgeon, plastic surgeon, or oculoplastic surgeon who has experience with blepharoplasty would be a great next step.