About ERA

Eastern Radiological Associates (ERA) is a professional partnership of board certified radiologists (doctors trained in medical imaging and image interpretation) who have been providing radiology professional services since 1970. Our mission is simple. Eastern Radiological Associates serves the patient and physician community of the region (Montana, Wyoming, and surrounding) by providing the highest quality diagnostic imaging and interventional services in a caring and compassionate atmosphere. Did you know? We are involved in the Yellowstone community… learn...

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Meet the Radiologists

Rex Dietz

Rex Dietz, MD

Rex Dietz is a board-certified radiologist and he is fellowship/sub-specialty trained in neuroradiology.

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X-RAY technology lets doctors see straight through human tissue to examine broken bones, cavities and swallowed objects. Modified X-ray procedures can be used to examine softer tissue, such as the lungs, blood vessels or the intestines. The X-ray camera uses the same film technology as an ordinary camera, but X-ray light sets off the chemical reaction instead of visible light. 



Diagnostic Ultrasound, also called ultrasound scanning or sonography, produces pictures of the inside of the body using sound waves. It involves the use of a small transducer (probe) and ultrasound gel placed directly on the skin. High-frequency sound waves are transmitted from the probe through the gel into the body. The transducer collects the sounds that bounce back and a computer then uses those sound waves to create an image. Ultrasound examinations do not use ionizing radiation (as used in x-rays), thus there is no radiation exposure to the...

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Transarterial Chemo-embolization (TACE)


What is transarterial chemoembolization (TACE)? Chemoembolization is a procedure that allows a dose of chemotherapy drugs to be administered directly to your tumor. This procedure allows for the chemo drugs to be given to the tumor and lessens the side effects associated with chemotherapy. TACE is most often used to treat liver tumors. How is TACE done? An anesthetic (numbing medicine) will be applied to your skin. Dr. Christenson will make a small incision in your groin then thread a catheter (small plastic tube) from your groin into the artery...

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