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. ERA provides a full range of professional radiology...

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Meet the Radiologists

Brian Christenson

Brian Christenson, MD

Brian Christenson is a board-certified radiologist. He is fellowship/ subspecialty trained in interventional radiology.

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Y-90 Radiotherapy for Liver Tumors


What is Yttrium-90 (Y-90) Radiotherapy? Y-90 Radiotherapy is a special procedure that is done to treat tumors in your liver. In this type of treatment, tiny radioactive beads are injected into the vessels that supply your liver tumor with blood. The tiny beads will stay in the blood vessels around your tumor and allow radiation to reach the tumor(s) directly. Because these beads are delivered directly to your tumor, there is very little effect on the healthy parts of your liver or other tissues around your liver. The beads will put off radiation...

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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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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.