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

Brandon, Jack

John (Jack) Brandon, MD

Jack Brandon is a board-certified radiologist and he is fellowship/subspecialty trained in neuroradiology.

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Coronary Computed Tomography Angiography (CCTA)

Heart and Ribs

What is CCTA? Coronary computed tomography angiography (CCTA) is a heart imaging test that helps determine if plaque buildup has narrowed a patient’s coronary arteries, the blood vessels that supply the heart. Plaque is made of various substances circulating in the blood, such as fat, cholesterol and calcium that deposit along the inner lining of the arteries. Plaque, which builds up over time, can reduce or in some cases completely block blood flow. Patients undergoing a CCTA scan receive an iodine-containing contrast material (dye) as an intravenous...

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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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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.