Board certified by the American Board of Surgery in General Surgery and Surgical Critical Care, Dr. Johnston is also the Trauma Medical Director of the Methodist Healthcare System, and a Clinical Associate Professor in the Department of Surgery at the University of Texas Health Science Center at San Antonio. Dr. Johnston is active in the medical community serving on the Methodist Healthcare Ministries’ Board and as Vice Chief of Staff at Methodist Stone Oak Hospital. He is also a former member of the San Antonio Metropolitan Health District Advisory Board and the former Chief of Surgery at Methodist Stone Oak Hospital. A Fellow of the American College of Surgeons, Dr. Johnston serves as an Ad Hoc reviewer for the Journal of Trauma and has collaborated on numerous published articles.


  • Undergraduate – Texas Tech University, Lubbock, Texas
  • Medical – University of Texas HSC-SA, San Antonio, Texas
  • Residency – University of Medicine and Dentistry of New Jersey, Morristown, New Jersey
  • Fellowship – Surgical Critical Care & Trauma, University of Texas HSC-SA, San Antonio, Texas

Clinical Interests:

  • Hernia and Abdominal Wall Reconstruction
  • Surgical Critical Care
  • Biliary Disease
  • Gastric Cancer
  • Benign and Malignant Breast Disease