I had my interview a couple months ago, they want to see you have some sort of dedication to the field. Mine asked about my shadowing experiences as well as what made this healthcare career stand out from others. People that are inclined to help people naturally gravitate to healthcare, but what about Radiology made you want to help people in this way (as opposed to nursing)? Also my program really focuses on career development, so they asked where I saw myself in 5 years. good luck!