If you have already had one blepharoplasty you will inevitably have less skin on your upper eyelids so any further skin excision can result in two potential problems, eyelids not closing and risk of severe dry eye and eye exposure, and eyebrows pulled down resulting in a very odd appearance. An oculoplastic surgeon can assess you and tell you what the risk is, checking the number of mm of eyelid skin remaining after your first blepharoplasty, checking the position of the skin crease, and the mobility of the eyebrows. There are minimum amounts of skin that have to be present for good eyelid closure and to keep an attractive small fold of skin on the upper eyelid which allows the eyebrows to remain in their normal position.