Dr. Thomas E. Callahan III, MD

Dr. Callahan practices at Dignity Health - Sierra Nevada Memorial Hospital in Grass Valley, California, part of CommonSpirit Health.

Dr. Callahan's NPI, 1508809138, was assigned on June 13, 2006. Dr. Callahan graduated from The Robert Larner, M.D. College of Medicine in 2000. Dr. Callahan holds Texas license M7890.

Dr. Callahan's primary practice is Dignity Health - Sierra Nevada Memorial Hospital, at 155 Glasson Way, Grass Valley, CA 95945 in Nevada County. The practice phone is (530) 274-6000.

Dr. Callahan's primary practice is Dignity Health - Sierra Nevada Memorial Hospital in Grass Valley, California, part of CommonSpirit Health. Dr. Callahan is also affiliated with Nor-Lea General Hospital. The medical group on file is Mercy Medical Group. Dmand AI also links Dr. Callahan to 1 more hospital, 7 medical groups and 3 group practices and clinics, each named with a free account.

Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Callahan practices, 6 sites in all. Vendor and product names are available with a free account.

Vascular and interventional radiology is Dr. Callahan's primary specialty in the NPI Registry, under taxonomy code 2085R0204X. Dr. Callahan is board certified in interventional radiology and diagnostic radiology by the American Board of Radiology. Dmand AI has Dr. Callahan's licenses on file in 7 states: Texas, New Mexico, California, Hawaii, Florida, Indiana and Massachusetts.

CMS data shows 915 Medicare services from Dr. Callahan across 25 procedure codes in 2024, for 794 Medicare patients. Medicare paid $13,113 for them. Every service was in a facility, such as a hospital, rather than an office.

CMS counts 794 Medicare patients who saw Dr. Callahan in 2024. The largest group is 65 to 74, with 337 patients. 75% of them have high blood pressure, and 75% have high cholesterol. 24% are also on Medicaid. Their average risk score is 2.12, where 1.00 is the Medicare average, so they are sicker than most Medicare patients.

Across all payers, Dmand AI patient panel data puts Dr. Callahan's median patient age at 58, with 60% women.

Dr. Callahan accepts Medicare assignment, so Medicare's approved amount is taken as full payment.

Dmand AI links 3 papers to Dr. Callahan, published from 2023 to 2025. Dr. Callahan has published most often in Radiol Case Rep.

CMS Open Payments shows 18 general payments to Dr. Callahan from 13 drug and device companies from 2016 to 2025. Food and beverage make up the largest share, 100% of the total. Stryker Corporation paid the most, $179.

Dr. Callahan graduated from The Robert Larner, M.D. College of Medicine in 2000.

Dr. Callahan is in network with 16 carriers, including Aetna, Elevance and Excellus BlueCross BlueShield. HMO plans come from the most carriers, 10. Check the plan with the practice before a visit.