No droopy eyelid (ptosis) is not a cause of post cataract double vision.
JCH MD
Can repairing the droopy eye lid also fix double vision caused by the lens implant?
Yes this is not an uncommon problem. It usually gets better however if not gone at 6 months it may not go away. See a oculoplastic surgeon. Find one at www.aao.org Surgery to lift the lid is sometimes indicated.
JCH MD