I am not certain I understand what your history has been. I can tell you that the aorta is commonly divided into sections: a part that comes out of the heart and goes toward your head (the ascending aorta), a part that arches over to the next section (the arch) , a part that comes off the arch and heads down towards you abdomen (the descending aorta) and a part that runs through your abdomen (the abdominal aorta). Here’s a description: https://my.clevelandclinic.org/health/body/17058-aorta-anatomy. Any part can contain an aneurysm. The type of surgery that’s required to repair an aneurysm can be different for the different sections. My understanding is that the abdominal and descending aorta typically require a less invasive surgery than the ascending aorta. I am not sure about the arch.

If you have an aneurysm in your abdominal aorta, it should be monitored. It sounds like your doctor is keeping track of it. The injection and scan I’d guess is a CT with contrast. As I understand it, that is commonly used to determine the size of the aneurysm. There is typically a size-based threshold for surgical repair. Also as I understand it, modern x-rays use much less radiation than they did 40 years ago, but the number of x-rays you are getting per year is still something your doctors should be tracking.

Good luck!