John McGahan, M.D.

John P. McGahan, M.D.




Radiology - Abdominal Imaging

Radiology - Body MRI

Radiology - Interventional Radiology

Radiology - Radiofrequency Ablation




  • Professor
To see if John P. McGahan is accepting new patients, or for assistance finding a UC Davis doctor, please call 800-2-UCDAVIS (800-282-3284).

Lawrence J. Ellison Ambulatory Care Center

4860 Y St.,, Suite 0100
Sacramento, CA 95817
Driving Directions

Primary Phone:

4860 Y St., Suite 3100
Sacramento, CA 95817
Driving Directions

Primary Phone:

Additional Phone Numbers

Physician Referrals: 800-4-UCDAVIS (800-482-3284)

Clinical Interests

Dr. McGahan is a leading interventional and diagnostic radiologist. He has pioneered the use of several innovative techniques, including the use of radiofrequency ablation to treat primary and metastatic tumors (with results comparable to traditional surgery, but with fewer risks). He also has used ablation techniques in the treatment of primary and metastatic liver, renal and lung tumors. He has treated benign and metastatic bone tumors as well. In addition, Dr. McGahan has investigated new techniques of tissue ablation for other organs, such as the prostate and breast. He has pioneered several other interventional techniques, including the development of percutaneous cholecystostomy as well as new techniques for endoluminal drainage of pelvic abscesses. He recently has studied the efficacy of abdominal ultrasound contrast in patients who have different diseases, including the use of ultrasound contrast in patients with hepatic or splenic injuries from blunt abdominal trauma.

Dr. McGahan was appointed as the chairperson by the American College of Radiology for its national Accreditation Program of Ultrasound Practices in the United States and Canada. He serves on the editorial board of several scientific journals and has edited six textbooks, including Diagnostic Ultrasound, A Logical Approach; Diagnostic Imaging of Fetal Anomalies; and most recently, an Atlas of Ultrasound Measurements.


Abdominal Imaging
Body MRI
Radiofrequency Ablation

Center/Program Affiliation

UC Davis Comprehensive Cancer Center


M.D., F.A.C.R., Oregon Health & Science University School of Medicine, Portland, Oregon, 1974

B.S., Gonzaga University, Spokane, Washington, 1970


UC Davis Medical Center, Sacramento, California, 1975-1979

Board Certifications

American Board of Radiology, 1979

American Board of Radiology, Vascular and Interventional Radiology, 1995

National Board of Medical Examiners, 1974

Professional Memberships

American College of Radiology, Fellow

American Institute of Ultrasound in Medicine, Fellow

American Roentgen Ray Society

Association of University Radiologists

International Hepato-Biliary Pancreatic Association

International Society of Biliary Radiology

Radiological Society of North America

Society of Biliary Radiology

Society of Radiologists in Ultrasound, Fellow

Select Recent Publications

Katzberg RW, McGahan JP. Science to practice: Will Gadolinium--enhanced MR imaging be useful in assessment of at-risk pregnancies? Radiology. 2011 Feb;258(2):325-6.

Lam D, Wootton-Gorges SL, McGahan JP, Stern R, Boone JM. Abdominal pediatric cancer surveillance using serial computed tomography: evaluation of organ absorbed dose and effective dose. Semin Oncol. 2011 Feb;38(1):128-35.

McGahan JP, Loh S, Boschini FJ, Paoli EE, Brock JM, Monsky WL, Li CS. Maximizing parameters for tissue ablation by using an internally cooled electrode.

Towner D, Gerscovich EO, Chiong BB, Rhee-Morris L, McGahan JP. Comparison of single versus multiple echogenic foci in the fetal heart regarding risk of aneuploidy. J Ultrasound Med. 2010 Jul;29(7):1061-7.

Holmes JF, Wisner DH, McGahan JP, Mower WR, Kuppermann N. Clinical prediction rules for identifying adults at very low risk for intra-abdominal injuries after blunt trauma. Ann Emerg Med. 2009 Oct;54(4):575-84. Epub 2009 May 19.

McGahan JP, Wu C. Sonographically guided transvaginal or transrectal pelvic abscess drainage using the trocar method with a new drainage guide attachment, AJR Am J Roentgenol, 191(5):1540-4, Nov 2008.

Naderi S, McGahan JP. A primer for fetal cardiac imaging: a stepwise approach for 2-dimensional imaging. Ultrasound Q. 2008 Sep; 24(3):195-206.

McGahan JP, Khatri VP. Imaging findings after liver resection by using radiofrequency parenchymal coagulation devices: initial experiences, Radiology, 247(3):896-902, Jun 2008.

Khatri VP, McGahan JP, Ramsamooj R, Griffey S, Brock J, Cronan M, Wilkendorf S. A phase II trial of image-guided radiofrequency ablation of small invasive breast carcinomas: use of saline-cooled tip electrode, Ann Surg Oncol, 14(5):1644-52, 2007 May.

McGahan JP, Horton S, Gerscovich EO, Gillen M, Richards JR, Cronan MS, Brock JM, Battistella F, Weisner DH, Holmes JF. Appearance of solid-organ injury with contrast-enhanced sonography in blunt abdominal trauma: Preliminary experience. Am J Roentgenol, 187(3):658-66, Sep 2006.

McGahan JP, Ro KM, Evans CP, Ellison LM. Efficacy of transhepatic radiofrequency ablation of renal-cell carcinoma. Am J Roentgenol, 186(5 Suppl):S311-5, May 2006.