Originally Posted by Loose rivets
Later I get the hint that this <strabismus> occurred after and because of the new lens. Is this the case?
Kinda sorta.
I always had some level of amblyopia (right eye weak) and was prone to convergence insufficiency at distance, but not close up, even as a child.
When my cataract developed I was studying the first year of an engineering degree, and as my vision in my left eye deteriorated, I learnt to get on ok (not great...) with my right eye. With the lens implant we attempted to give my left eye good uncorrected distance vision, but the surgeon overlapped the cornea tissue slightly too much (or maybe not enough) when closing up, resulting in tension which flattened my cornea on one axis - hence 2.5 diopters of cyl where once there was none.
At that stage, although it was suggested I might experience problems, I still converged OK most of the time.
Then four years later, six weeks before the end of my engineering degree I suffered a detached retina in my left eye. Risk factors include male, ~30yo, myopia, cataract surgery, laser capsulotomy (treatment for a complication of the cataract surgery). The only risk factor I didn't have was bungy jumping! I spent the final six weeks of my degree with my good eye patched, and without a period of adjustment, I struggled with things like reading. Driving was definitely right out!
When the patch came off, my eyes no longer converged at all. I could sort of push them to converge, but it was just uncomfortable, a bit like trying to cross your eyes, so I didn't.
So it wasn't a direct result of cataract surgery and it certainly isn't a typical effect of cataract surgery, which for anyone here who might find themselves facing it, is one of the safest and most successful surgeries around, with an absurdly high success rate. It is said to be one of the most satisfying surgeries to perform, if somewhat boring, because patients are almost universally delighted with the outcome.
The weekend before my surgery I was (trying to) fly a hang glider. As a novice, I was having enormous difficulty judging the flare over a featureless beach with only one eye, and at one stage, sitting in the shade of the glider eating lunch, I closed my good eye and could not even detect the colour of the glider fabric with the sunshining through it. The day after my surgery, they took the patch off my eye and I could see the doctors newspaper on his desk on the far side of the room in glorious living colour. That's not something you forget.