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


Joseph Dillard, MD

Joseph Dillard is a board-certified radiologist and he is fellowship/sub-specialty trained in neuroradiology and interventional and vascular radiology.

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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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Fluoroscopy is a study of moving body structures–similar to an X-ray “movie.” A continuous X-ray beam is passed through the body part being examined. The beam is transmitted to a TV-like monitor so that the body part and its motion can be seen in detail. Read more: http://www.radiologyinfo.org/en/info.cfm?pg=modbariumswallow

Tumor Microwave Ablation

liver diagram

What is tumor microwave ablation? Tumor microwave ablation is a procedure that uses microwave energy to destroy cancer cells. Microwave ablation is used to treat tumors of the liver and some other tumors including bone tumors. How is tumor microwave ablation done? A needle-like microwave antenna will be placed inside with the tumor, more than one applicator may be used depending on the tumor size and location. Dr. Christenson will use ultrasound and other x-ray imaging to guide the antenna(s) to the treatment site. Once the antenna is in the correct...

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