I've been looking at this space for a few years. I've come to the conclusion that one of the biggest obstacles to ML replacing/supplementing radiologists is the malpractice ambiguity. If a doctor misses a lesion on a chest Xray, the lawyers know who to sue. What if a ML algorithm that no human understands misses this. Who is liable? It's another sad example of technological progress in healthcare being stifled by bureaucracy / liability concerns.