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Avera Brain & Spine Institute

Plaza 2
1301 S. Cliff Avenue
Sioux Falls, SD 57105
(605) 322-7270

Avera Neuroscience Institute Neurologists

Dr. BoyleJeffrey Boyle, MD

Dr. Boyle is a graduate of the University of Nebraska Medical Center. He completed his residency at the University of Iowa Hospitals and Clinics and a Fellowship and Sleep Medicine at the University of Iowa. He is certified by the American Board of Psychiatry and Neurology in Sleep Medicine and Neurology. Dr. Boyle joined the Sioux Falls community in August of 2014. He and his wife have 4 young boys of which he is quite proud. His areas of practice interest include the use of telemedicine in stroke evaluation and management, sleep disorders, and general neurology.

Dr. Carol B. MilesCarol B. Miles, MD

Dr. Carol Miles, originally from Viborg, South Dakota, graduated from The University of South Dakota with a Bachelor of Science degree, and later earned her medical degree from The University of South Dakota School of Medicine. She completed a one-year internship at Sioux Valley Hospital in Sioux Falls, and later completed neurology training at the University of Vermont in Burlington, Vt.

Dr. Miles has practiced in Sioux Falls since completing her residency program in 1995. She is board certified with the American Board of Neurology, and is a member of the American Academy of Neurology, South Dakota Medical Association, American Medical Association and the National Headache Foundation.

Dr. William R. Rossing

William R. Rossing, MD

Dr. Rossing is a native of Sioux Falls. He earned his Bachelor of Arts degree from Augustana College and his medical degree from The University of South Dakota School of Medicine in 1990. He completed his neurology residency training at the University of Wisconsin, Madison Campus. Dr. Rossing has maintained his board certification with the American Board of Psychiatry and Neurology since completion of his neurology residency in 1994.

A proud member of Neurology Associates, P.C., since August of 1994, Dr. Rossing practices general neurology with special areas of interest in movement disorders, medical neurotoxin therapy, stroke and multiple sclerosis. He is currently the medical director of the Avera McKennan Hospital Stroke Center and is chairman of the Department of Neurosciences at Avera McKennan Hospital. Dr. Rossing sees patients at his Sioux Falls practice location as well as the Sioux Falls Veterans Hospital Outpatient Clinic. His outreach clinic is located at Prairie Lakes Healthcare System in Watertown, South Dakota.

Dr. Todd A. Zimprich

Todd A. Zimprich, MD

Dr. Zimprich is a native of North Dakota. After attending medical school at Louisiana State University in New Orleans, La., he completed his neurology residency at the Mayo Clinic in Rochester, Minn. He also spent one year of additional subspecialty training in EMG/electrodiagnosis at the Mayo Clinic.

Dr. Zimprich is board certified and has been in practice with Neurology Associates since 2002. While he enjoys the challenges associated with the management of all neurological disorders, Dr. Zimprich has a special interest in the diagnosis and treatment of peripheral neuropathy, syncope and autonomic disorders. He is specially trained in the objective evaluation of the nervous system utilizing a variety of electrodiagnostic methods, including specialized EMG/NCS techniques, evoked potentials and autonomic reflex studies.

Dr. Lisa C. Viola

Lisa C. Viola, D.O.

Dr. Viola is a well-respected and accomplished neurologist, passionate about her work and the premier neurological care that her team provides to patients at the Avera McKennan Neuroscience Institute.

Dr. Viola completed her training at Albert Einstein College of Medicine in New York City, after which she fulfilled a fellowship in clinical neurophysiology and neuromuscular diseases, specializing in EMG training. She is board certified in three specialties which include neurology, clinical neurophysiology and electrodiagnostic medicine. Dr. Viola has been a partner of Neurology Associates, PC, since moving to South Dakota more than 5 years ago.

Dr. Warren O.V. Opheim Warren O. V. Opheim, MD

Dr. Opheim is a native of Sioux Falls, who graduated with a Bachelor of Arts degree from Augustana College and earned his medical degree at The University of South Dakota and University of Minnesota.

He received his training in neurology at the University of Minnesota. Following completion of his training, Dr. Opheim returned to Sioux Falls in 1977 to practice neurology.

Dr. Karen R. Garnaas

Karen R. Garnaas, MD

Dr. Garnaas is the newest member of the Avera Neuroscience team. A North Dakota native, she joins Avera after practicing in North Dakota for the past 13 years. While there, she developed centers of excellence in neuromuscular and multiple sclerosis care and served as the director of the region's largest and most comprehensive EMG laboratory.

She earned her medical degree from Mayo Medical School in Rochester, Minn., completed her residency with the University of Michigan in Ann Arbor, Mich. and her fellowship with Mayo Graduate School of Medicine in Rochester, Minn. She is board certified in electrodiagnostic medicine as well as psychiatry and neurology.

Dr. Garnaas specializes in adult neurology, neuromuscular diseases, multiple sclerosis, therapeutic botulinum injections and electromyography.

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