Avera Neuroscience Institute Neurosurgeons
Michael R. Puumala, MD, PC
Dr. Puumala was born in Highland Park, Illinois. He earned his undergraduate degree from Carleton College in Northfield, Minn. in 1985, and went on to graduate from Mayo Medical School in Rochester, Minn. in 1990.
In 1991, he continued his studies at the Mayo Graduate School of Medicine and completed his residency in neurological surgery in 1996. Upon completing his work in Rochester, Dr. Puumala practiced in Mayo Clinics in Jacksonville Florida and Scottsdale Arizona, where he served as chief resident for the level I trauma center.
Dr. Puumala specializes in adult and pediatric neurosurgery, including all aspects of surgical problems related to the brain and spine; tumors of the brain and spine; cerebral vascular problems. He has board certifications from the American Board of Neurological Surgery (2001), the South Dakota Board of Medical Examiners (1996), the American Board of Neurological Surgery (1993), the National Board of Medical Examiners (1991) and the Minnesota Board of Medical Examiners (1991).
Daniel G. Tynan, MD 
Originally from the Chicago area, Dr. Tynan joins Avera Neurosurgery after 17 years of neurosurgery practice. He received his MD from the University of Illinois at Rockford and completed his surgical internship and neurosurgery fellowship at the Mayo Clinic in Rochester, Minn.
Dr. Tynan moved to Sioux Falls in 2000 after 9 years of neurosurgery practice in Twin Cities, Minn. He is certified by the American Board of Neurological Surgery.
Dr. Tynan's general neurosurgical practice provides services involving surgery of the spine, which includes disc herniations, spinal stenosis, tumors, degenerative and traumatic spine problems, brain tumors, cerebral aneurysms, peripheral nerve surgery, endoscopic neurosurgery and functional neurosurgery for trigeminal neuralgia/epilepsy/chronic pain.
Hamid R. Abbasi, MD, PhD 
Dr. Abbasi joins the Avera Neuroscience Institute after receiving his MD in 1996 and obtaining his PhD in computer science and computer assisted surgery in 1998 from the University of Heidelberg, Germany.
He studied at Stanford University in California and Dartmouth College in New Hampshire. He finished his residency at the University of Texas Medical Branch, Galveston, which included extensive training in brain, spine and pituitary tumors at MD Anderson Cancer Center; functional neurosurgery and complex spine at Methodist Hospital; and vascular and pediatrics neurosurgery at Memorial Hermann-Texas Medical Center. He is board eligible for the American Board of Neurosurgery and is a member of both the Congress of Neurological Surgeons and American Association of Neurological Surgeons.
Dr. Abbasi's passion is helping people and gaining the respect of patients. His interests are in brain and spine tumors, pituitary tumors, complex spine, computer-assisted surgery, neuroendoscopy as well as functional neurosurgery.
Delaina P. Sievers, PA-C
