Our Physicians
For 55 years, Lake Medical Imaging has earned our standing as one of the most respected diagnostic imaging practices in the country.
We continue to garner national recognition for our quality of patient care and safety from some of the field’s most respected professional organizations.
We have grown to be one of a few full-service radiology practices specializing and fully accredited in MRI, CT, PET/CT, Women’s Imaging, Nuclear Medicine, and Interventional Radiology.
Meet Our Physicians
Cathrine E. Keller, M.D.
Cathrine E. Keller, M.D.
- Immediate Past President and Managing Physician (2005-January 6, 2023)
- Medical Degree: University of Chicago, Pritzker School of Medicine
- Residency: Chief Resident, Diagnostic Radiology, Henry Ford Hospital, Detroit
- Fellowship: Neuroradiology, University of Miami, Jackson Memorial Medical Center
Michael S. Levine, M.D.
Michael S. Levine, M.D. / Part-time
- Medical Degree: SUNY – Upstate Medical Center, Syracuse, New York
- Residency: Chief Radiology, Mount Sinai Medical Center, Miami Beach, Florida
Radiology, Medicine, SUNY – Upstate Medical Center, Syracuse, New York - Fellowship: Interventional Radiology, University of Lund, Lund, Sweden
- Board Certification:
American Board of Nuclear Cardiology
American Board of Diagnostic Radiology
American Board of Internal Medicine
David C. Weyn, M.D.
David C. Weyn, M.D.
- Medical Degree: Jefferson Medical College, Philadelphia
- Residency: Internal Medicine, Cooper Hospital, University Medical Center, Camden; Diagnostic Radiology, Albert Einstein Medical Center, Philadelphia
Marc S. Schwartzberg, M.D.
Marc S. Schwartzberg, M.D.
- Medical Degree: University of North Carolina at Chapel Hill
- Residency: Chief Resident, Diagnostic Radiology, University of Alabama
- Fellowship: Angiographic and Interventional Radiology, University of Alabama
CERTIFICATE OF ADDED QUALIFICATION: VASCULAR AND INTERVENTIONAL RADIOLOGY
Manoj Bhatia, M.D.
Manoj Bhatia, M.D.
- Medical Degree: Northwestern University Medical School
- Residency: Diagnostic Radiology, Medical University of South Carolina
- Fellowship: Musculoskeletal and Body MRI, Thomas Jefferson University
George E. Kainz, M.D. / President and Managing Physician
George E. Kainz, M.D.
- President and Managing Physician
- Medical Degree: University of Miami School of Medicine
- Residency: Chief Resident, Diagnostic Radiology, Robert Wood Johnson Medical School, Camden
- Fellowship: Abdominal and Cross-Sectional Body Imaging, Temple University Hospital, Philadelphia
Pairoj Sae Chang, M.D. Ph.D.
Pairoj Sae Chang, M.D. Ph.D.
- Medical Degree: Loma Linda University School of Medicine, California; Ph.D. Biochemistry, Molecular Biology, Loma Linda University
- Residency: Resident, Internal Medicine and Co-Chief Resident, Diagnostic Radiology Loma Linda University Medical Center
- Fellowship: Vascular and Interventional Radiology, Loma Linda University Medical Center
- Certificate of Added Qualification: Vascular and Interventional Radiology
Yi Liu, M.D., Ph.D.
Yi Liu, M.D. Ph.D.
- Medical Degree: Capital University of Medical Sciences, Beijing, China; Ph.D., Neuroscience, Hahnemann University, Philadelphia
- Residency: Department of Radiology, Hospital of University of Pennsylvania; Department of Surgery, Long Island Jewish Medical Center; Department of Neurosurgery, Beijing Tian Tan Hospital, Beijing
Richard K. Held, M.D.
Richard K. Held, M.D.
- Medical Degree: Ross University School of Medicine, Edison, New Jersey
- Residency: Internal Medicine and Diagnostic Radiology, Norwalk Hospital, Norwalk, Connecticut
- Fellowship: Nuclear Medicine Mallinckrodt Institute of Radiology, St. Louis, Missouri
- Additional Board Certification: Nuclear Medicine
J. Laird McMullen, III, M.D.
J. Laird McMullen, III, M.D.
- Medical Degree; University of South Florida College of Medicine
- Residency: Co-Chief Resident, Diagnostic Radiology, University of South Florida College of Medicine
- Fellowship: Interventional Radiology, University of Virginia Health System
CERTIFICATE OF ADDED QUALIFICATION: VASCULAR AND INTERVENTIONAL RADIOLOGY
J. Scott Carroll, M.D.
J. Scott Carroll, M.D.
- Medical Degree: Medical University of South Carolina
- Residency: Diagnostic Radiology, Baptist Memorial Hospital, Memphis
- Fellowship: Musculoskeletal Radiology, Case Western Reserve, Cleveland
Keith Kastelic, M.D.
Keith A. Kastelic, M.D.
- Medical Degree: University of Illinois, Peoria
- Residency: Diagnostic Radiology, University of Missouri, Kansas City
Brittany Nagy, M.D.
Brittany Nagy, M.D.
- Medical Degree: Drexel University College of Medicine, Philadelphia
- Residency: Diagnostic Radiology, Emory University School of Medicine, Atlanta
- Fellowship: Vascular and Interventional Radiology, University of Florida College of Medicine
Marcus Kessler, M.D.
Marcus Kessler, M.D.
- Medical Degree: Medizinische Fakultat, University of Cologne, Germany
- Residency: Nuclear Medicine, Mallinckrodt Institute of Radiology, St. Louis;
Diagnostic Radiology, Pediatric Hospital Amsterdamer Strasse, University of Cologne, Germany; Diagnostic Radiology and Nuclear Medicine, Hospital Cologne-Holweide, Germany
- Fellowships: Nuclear Medicine, The University of Arkansas for the Medical Sciences, Little Rock; Neuroradiology and Pediatric Radiology, Mallinckrodt Institute of Radiology, St. Louis
David Factor, M.D
David Factor, M.D.
- Medical Degree: Rush Medical College, Chicago, IL
- Residency: Radiology, Tripler Army Medical Center
Kenneth Mandato, M.D.
Kenneth Mandato, M.D.
- Medical Degree: Boston University School of Medicine, Boston
- Residency: Diagnostic Radiology, State University of New York, Stony Brook
- Fellowship: Cardiovascular and Interventional Radiology, Albany Medical Center Hospital,
Albany, NY
Stephen Z. Grahovac, M.D.
- Medical Degree: University of Ottawa Medical School, Ottawa, Canada
- Residency: Diagnostic Radiology, Ottawa General Hospital, Ottawa, Canada
- Fellowship: Neuroradiology, McGill University Montreal Neurological Institute,
Montreal, Canada
Steven Hwang, D.O.
Steven Hwang, D.O.
- Medical Degree: A.T. Still University, School of Osteopathic Medicine, Mesa, AZ
- Residency: Chief Resident, Diagnostic Radiology, Larkin Community Hospital, South Miami, FL
- Fellowship: Body/Abdominal Radiology, University of Colorado School of Medicine, Aurora, CO
Rafik Ben Abda, D.O.
Rafik Ben Abda, D.O.
- Medical Degree: Des Moines University, School of Osteopathic Medicine, Des Moines, IA
- Residency: Diagnostic Radiology, Madigan Army Medical Center, Tacoma, WA
- Fellowship: Neuro Radiology, Yale University, New Haven, CT
Kyle Hopkins, PA-C
Kyle Hopkins, PA-C
Kyle Hopkins is a practitioner with Lake Medical Imaging as an Interventional Radiology Advanced Practice Provider. He joined our team in 2024 and practices at our imaging centers and at the UF Health Hospitals in Central Florida.
Education: Master of Physician Assistant, University of Tampa
Clinical Rotations:
- Interventional Radiology at HCA Florida Largo Hospital
- Surgical Medicine at AdventHealth Medical Group Tampa, FL
- Emergency Medicine at HCA West Florida & James A. Haley VA Hospital
- Internal Medicine at AdventHealth Tampa, FL
- Women’s Medicine at New Tampa OB/GYN
- Pediatric Medicine at Tampa Family Health Centers W Hillsborough
- Behavioral Medicine at Stedman Clinical Trials
- Family Medicine at Evara Health Tarpon Springs
