Dr. Edward Gabriel, M.D., DABR

CEO, Managing Partner

With over 35 years of medical and leadership experience, Dr. Gabriel has been the CEO and managing partner of RMG since 2013.

Dr. Gabriel completed his undergraduate degree at UCLA and obtained his Medical Doctorate at Rosalind Franklin University/Chicago Medical School. Both his undergraduate and medical degrees emphasized digital applications in medicine and medical informatics. Dr. Gabriel completed his Residency and Fellowship training in Diagnostic Radiology from Loma Linda University/White Memorial Campus.

Upon completion of his Residency and Fellowship training, he joined RMG as a partner and outpatient medical director. He is a graduate of the USC Marshall School of Business’ Physician Leadership Program and has held medical director roles for both outpatient and inpatient radiology departments at Adventist Health White Memorial and Adventist Health Enterprise hospitals. Dr. Gabriel is currently the Chair of the Diagnostic Imaging Department at the White Memorial Medical Center. He continues to teach residents in all subspecialties including Diagnostic Radiology and has had the privilege to serve as the associate professor of radiology at Loma Linda University for over 20 years.

Carla Kefalas, CRA, R.T.(R)(M)(MR)(ARRT)

Director of Operations & Business Development

Carla is the newest member of RMG in her role as the director of operations and business development. Carla’s 20 years with Adventist Health in multiple roles, both clinically and as a member of the management team, pairs the administrative and clinical approach of RMG’s design. She has experience in the for-profit and not-for-profit health institutions as well as the complexities of a union environment.

Carla began her radiology journey graduating from Loma Linda University Radiologic Technology program in 1994 and extended her education with an emphasis in management. In the subsequent years, Carla has held multiple roles such as: lead mammography technologist, diagnostic imaging coordinator, supervisor, and operations manager. In 2015, she graduated from UCLA’s Healthcare Leadership and Management School of Public Health and successfully obtained her CRA (Certified Radiology Administrator) credential.

Her experience with Adventist Health, Providence, Comprehensive Imaging Partners of Orange County, and Long Beach Memorial Medical Center has established the skillset necessary to engage radiologists and hospital administrators to address the variable departmental needs and challenges that RMG supports.

Tony Nahas, B.S.

Strategic Advisor

Tony has been closely linked with RMG since 1993. He has extensive knowledge in the public and private sector regarding medical billing, contracting, tax laws, as well as state, local and federal regulations.

Tony graduated from Cal Poly Pomona in 1976 with a degree in Economics. His first 6 years began in the private sector. He then, catapulted his career for the next decade honing his skills as the director of accounts receivables for Adventist Health in the Southern California area.

In the last 20 years, Tony has played a pivotal role with RMG and the successful implementation of billing, compliance, payroll, and contract negotiations. He has evolved from business manager to director of business management to presently, strategic advisor where he will continue his instrumental contributions to RMG.

Ruth Johnston

Senior Administrative Assistant & Credentialing Coordinator

For the past 19 years, Ruth Johnston has effectively represented RMG Medical Imaging Consultants. As the senior administrative assistant and credentialing coordinator, she works closely with over forty Radiologists and ten hospitals to ensure an efficient and effective partnership for RMG. She prepares and maintains practitioner credentialing files for approval by the Credentialing Leadership to comply with Medical Staff Offices, Joint Commission (“TJC”), American College of Radiology (“ACR”), policies & procedures, and regulatory agency requirements.