This review is somewhat multi-disciplinary in nature. As you wrap up your reviews, one of the things I found useful was to create tons of different lists. Regardless of which test you're studying for, there are many questions that are organized differently than how one might go about learning a particular disease. As such, I started making lists of different ways to group otherwise disparate diseases that might show up as a test question, or at least help me remember a specific feature of the disease.
Corneal dystrophies are clinically fairly rare (with notable exceptions) but have pretty easily identifiable appearances. Because we have learned quite a bit about the genetics, inheritance, etc. about many of the dystrophies, this seemed to be a pretty popular topic on tests – though it seemed like in the past few years the number of questions on corneal dystrophies decreased quite a bit. I don’t know the minds of the test-writers, so who knows if it was a random thing, or if there was more emphasis on clinically significant questions.