Hi,

A radiologist is someone who reads and interprets imaging or radiology exams, such as CT, MRI, and X-ray.

A Nuclear Medicine physician also reads and interprets imaging, but some types of imaging are not called radiology – they are called nuclear medicine, or nuclear imaging.

In dollars, 

For Radiologist - Median annual salary: $58,960

For Nuclear Medicine physician - Median annual salary: $74,350

Hope this helps.