Yup. Cataracts are the best example of a deterministic radiation effect; i.e. receive X dose and you _will_ receive Y result. While cancer induction is stochastic; probabilistic effect of exposure.
That part of the story made me wonder why the cataracts haven't been treated. There are relatively low-risk and well-understood treatments for cataracts that do a very good job restoring vision.
Easy procedure for an individual with insurance in the US or EU, is the same true for Eastern Europe? IDK
Cost? The URSS was already declining by then, and Ukraine was “born poor” in many ways. A procedure might well be safe and effective, but if the local health service can’t afford to do it thousands of times, they will just ignore it.
Not sure where he lives, but in Russia this surgery is covered by mandatory medical insurance.