What we do

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.

The Interventional Radiology Clinic (IR Clinic) is operated by Dr. Christensen as part of Eastern Radiological Associates. The IR Clinic is independent, but all state-of-the-art procedures are performed in specialized areas at St. Vincent Healthcare. Most patients are referred to the IR clinic by oncologists, nephrologists, or other treating physicians and professionals, however, patients may also be self-referred.

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Meet the Radiologists


Kathleen Ryan, MD

Dr. Ryan is a board-certified radiologist, specializing in Breast Imaging.

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Neurologic Imaging

Neuroradiology is a subspecialty of radiology, focusing on the diagnosis and characterization of abnormalities of the central and peripheral nervous system, spine, and head and neck. Neurologic imaging methods include computed tomography (CT) and magnetic resonance imaging (MRI). Ultrasound is used in limited circumstances, in particular in the pediatric population. Angiography is traditionally used for diagnosis of vascular abnormalities or diagnosis and characterization of masses or other lesions but is being replaced in many instances by CT...

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Liver 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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headache sufferer

What is Sphenopalatine Ganglion? The Sphenopalatine Ganglion (SPG) is a group of nerves located in the skull behind the nasal passages. The SPG is also associated with the trigeminal nerve, the principle nerve involved in headache disorders. The SPG block may provide relief for a variety of pain syndromes including: Trigeminal neuralgia Sphenopalatine neuralgia Migraine headaches Cluster headaches Facial pain Temporomandibular joint pain Postherpetic neuralgia How is a SPG block done? We may apply a small amount of numbing medicine on a cotton...

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