Dysgraphia, LD in written expression, and Disorder of Written Expression are all names for the same thing.

And the research on vision therapy is that it can be helpful for some of the things others mentioned, like tracking and convergence, but will not remediate underlying learning disabilities, such as those in reading or writing, as those involve different parts of the brain, having to do with language processing, phonological processing, orthographic mapping, etc., not vision per se.

...pronounced like the long vowel and first letter of the alphabet...