Physicians
We want you to know:
The specialist who referred you to our center, as well as most of the physicians who do procedures here, are also part owners of the center. You have other choices, and we will be very happy to discuss those alternatives with you. Just call us at (918) 528-4221.
Physicians who currently have privileges at our center:

Matt M. Blankenship, M.D.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: Oklahoma University College of Medicine
• Residency: Oklahoma University College of Medicine, Tulsa
• Fellowship: University of Oklahoma Health Sciences Center

Certification & Licensure
American Board of Internal Medicine, American Board of Gastroenterology, Oklahoma State Licensure

www.adultgastro.com
 




Brandon A. Conkling, D.O.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: Oklahoma State University, Tulsa
• Residency: Tripler Army Medical Center, Honolulu, Hawaii
• Fellowship: Texas A&M University, Temple, Texas

Certification & Licensure
American Board of Internal Medicine, American Board of Gastroenterology, Oklahoma State Licensure

www.adultgastro.com
 




Gary L. Hills, D.O.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: Michigan State University – College of Osteopathic Medicine
• Residency: Flint Osteopathic Hospital
• Fellowship: Botsford Hospital in Farmington Hills, Michigan

Certification & Licensure
American Osteopathic Board of Internal Medicine, American Osteopathic Board of Gastroenterology, Oklahoma State Licensure

www.adultgastro.com
 




Stephen S. Hwang, M.D., Ph.D.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: CMC, Taiwan
• Ph.D.: Duke University
• Residency: Duke University
• Fellowship: University of California, San Francisco

Certification & Licensure
American Board of Gastroenterology, Oklahoma Medical Licensure

www.adultgastro.com
 




Craig S. Johnson, M.D.

Specialty: Colon and Rectal Surgery

Education
• Medical School: University of Oklahoma Health Sciences Center
• Residency: University of Oklahoma Health Sciences Center, Tulsa
• Fellowship: Louisiana State University

Certification & Licensure
American Board of Surgery, American Board of Colon and Rectal Surgery, Okahoma Medical Licensure

www.surgassoc.com
 




Douglas B. Kliewer, M.D.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: University of Oklahoma College of Medicine
• Residency: University of Texas Southwestern
• Fellowship: University of Texas Southwestern

Certification & Licensure
American Board of Internal Medicine, American Board of Gastroenterology, Oklahoma Medical Licensure

www.adultgastro.com
 




Nicholas D. Mamalis, M.D.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: Emory School of Medicine
• Residency: University of Missouri, Kansas City
• Fellowship: University of Alabama in Birmingham

Certification & Licensure
American Board of Internal Medicine, American Board of Gastroenterology, Oklahoma Medical Licensure

www.adultgastro.com
 




Markham L. Nightengale, M.D.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: Oklahoma University Health Sciences Center
• Residency: Mayo Clinic in Rochester, Minnesota
• Fellowship: Baylor University Medical Center in Dallas

Certification & Licensure
American Board of Internal Medicine, American Board of Gastroenterology, Oklahoma Medical Licensure

www.adultgastro.com
 




Paul D. Stanton, M.D.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: University of Texas Southwestern Medical School
• Residency: University of Oklahoma College of Medicine
• Fellowship: University of Texas Health Sciences Center in San Antonio

Certification & Licensure
American Board of Internal Medicine, American Board of Gastroenterology, Oklahoma Medical Licensure

www.adultgastro.com
 




Patrick R. Volak, M.D.

Specialty: Internal Medicine, Gastroenterology

Education
• Medical School: University of Oklahoma College of Medicine
• Residency: University of Oklahoma College of Medicine
• Fellowship: University of Oklahoma

Certification & Licensure

American Board of Internal Medicine, American Board of Gastroenterology, Oklahoma Medical Licensure

www.adultgastro.com