I am currently studying to be a radiologist. The technology used to view and treat diseases within the human are amazing! 
Interesting, what does a radiologist do exactly ?
They prepare and use imagining technology like X-rays, CT scans and ultrasound machines to help diagnose patients. If you've ever broken a bone, you've probably met one.
OK, and when radiology was invented ?
The first uses of such technology go back to the early 1900s, but possibly even before. The exact time isn't super clear. 
I did not expected to be so old, it seems that CT scanners were introduced in hospitals in the last 40 years, am I right ?
Sort of. The first commercially available CT scanner was developed in the 1960s, but the machines were around since the 1910s. 
Oh, sorry, and how does a CT scanner works ?
CT scan
A CT scan or computed tomography scan (formerly computerized axial tomography scan or CAT scan) makes use of computer-processed combinations of many X-ray measurements taken from different angles to produce cross-sectional (tomographic) images (virtual "slices") of specific areas of a scanned object, allowing the user to see inside the object without cutting.
Digital geometry processing is used to further generate a three-dimensional volume of the inside of the object from a large series of two-dimensional radiographic
Radiology
Radiology is the medical specialty that uses medical imaging to diagnose and treat diseases within the human body.
A variety of imaging techniques such as X-ray radiography, ultrasound, computed tomography (CT), nuclear medicine including positron emission tomography (PET), and magnetic resonance imaging (MRI) are used to diagnose or treat diseases. Interventional radiology is the performance of usually minimally invasive medical procedures with the guidance of imaging technologies such as X-ray radiography, ultrasound, computed tomography (CT), nuclear