Your mother it seems developed secondary glaucoma i.e. raised eye pressure. The raised eye pressure can damage the optic nerve of the eye and cause blindness in the affected eye. Raised eye pressure can also cause pain in the eye and also headache on the affected side. By loose implant I believe your doctor means that the lens placed in her eye is not stable. If that is the cause then the lens may fall back in the vitreous cavity of the eye and may cause retinal detachment and loss of vision. However, it may not so unstable to fall back. An examination can only confirm that.
There may be 2 options. First, is to control eye pressure with medications. If the lens is not that unstable and pressure can be controlled on drops then she may not go for surgery. The second option is surgery to remove the unstable lens with or without another lens. You can discuss it with your treating doctor. Thanks and best wishes.
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