These case sets are intended to supplement Abdominal 101 and your CT rotations during residency. Several sets are multiple presentations of a single diagnosis, which will help you to really a get a sense for how to make these diagnoses confidently. Others are groups of related diagnoses, which will help you cluster your knowledge and link key concepts, making them more memorable.
For medical students, I suggest selecting a diagnosis or topic of interest and reviewing the variety of imaging findings. For residents/fellows, I recommend reviewing any diagnosis that (1) you have not seen after your first CT rotation and (2) you are not very comfortable with after your second CT rotation, particularly before taking independent call.
You may only encounter some of these diagnoses 1-2 times during training. For example, there are 6 surgically proven closed-loop obstruction cases, 3 gallstone ileus, and 5 perforated ulcers. Seeing several examples of a relatively uncommon diagnosis will really help you solidify your learning!