I am currently attending Weber State University in their Radiologist Assistant program. It is mainly an online gig, but you fly to Utah every other month for classes. It is 20 months long, and there is full class load and internship the entire time. To get into the program, you need to be an ARRT certified Radiologic Techologist for 3 years (no bachelor degree needed as someone else stated) and have some prereq. stuff done (specifics at weber.edu/radsci). You graduate with an advanced bachelors degree and they are currently developing a master's program that will only require 2 or 3 more classes. Someone brought up PAs vs. RAs. Here is what I think...I have specialized in Radiography for many years assisting with procedures and looking at films. Now, I have advanced, intense training in performing those procedures and analyzing the films. Who would you want doing the procedure? My rads love RAs. They get to spend more time reading MRIs and CTs, while I do the procedures that take the most time.
I thought that when I graduated from xray school that I was never going to do anything else. Eventually, I just wanted more responsibility (and $$), and this meets both of those expectations. I do whatever the rads entitle me to do, and what medicare/medicaid will reimburse for (they are picky about the rad being present for some procedures. This doesn't mean they have to DO it, just be present for certain portions like intra-articular contrast injections)
Any other questions feel free to ask. Also, I have a friend from the Buffalo area that is in my class, so New Yorkers can do it, and laws up there are very lenient for what an RPA or RA can do. (Weber is an RPA/RA school)