Irene Yu, MD

Dr. Ramsay Fuleihan is the clinical director of the Division of Pediatric Allergy, Immunology and Rheumatology and a professor of pediatrics at Columbia. Throughout his career his main research interest has been the pathogenesis and treatment of primary immunodeficiency diseases. Dr. Fuleihan was formerly chief of the division of allergy and immunology at Sidra Medical and Research Center in Qatar, and Director of Primary Immunodeficiency Clinical Services and the Jeffrey Modell Diagnostic and Research Center for Primary Immunodeficiencies at Ann & Robert H Lurie Children’s Hospital of Chicago. Dr. Fuleihan earned his medical degree from the American University of Beirut in Lebanon, completed his pediatric residency at Duke University Medical Center, and fellowship in allergy and immunology at the Children’s Hospital-Boston at Harvard Medical School. Dr. Fuleihan is a member of the Board of Directors of the American Board of Allergy and Immunology. He is an active fellow of the American Academy of Allergy Asthma and Immunology, where he served as Chair of the Primary Immunodeficiency Committee; a member of the Clinical Immunology Society, where he served as chair of the CME committee; a member of the European Society for Immunodeficiencies; and a member of the Society for Pediatric Research. He serves on the Medical Advisory Committee of the Immune Deficiency Foundation and on the Board of Directors of Bounce Children’s Foundation.

Justin K. Greisberg, MD, is an orthopedic surgeon specializing in foot and ankle reconstruction and complex musculoskeletal trauma. Dr. Greisberg is Chief of Foot & Ankle Orthopedics, Chief of Orthopedic Trauma, at NewYork-Presbyterian-Lawrence Division, and Professor of Orthopedic Surgery, Columbia University. Dr. Greisberg is an expert on complex reconstructive surgeries, limb realignment, diabetic reconstruction, Achilles tendon injuries, stress fractures, and total ankle replacement. His practice leverages advanced minimally invasive arthroscopic techniques, combined with the latest medications, braces, and orthotics to ensure accelerated recovery times. Following medical school and residency training, Dr. Greisberg completed advanced fellowship training in both foot and ankle surgery and orthopedic trauma. As chief of the foot and ankle service at Columbia University Irving Medical Center, Dr. Greisberg's practice – based in Manhattan and Westchester County – is supported by the full resources of the NewYork-Presbyterian Hospital system, and he frequently receives emergency trauma cases from across the region. In addition to his clinical practice, Dr. Greisberg is also a highly respected scholar who is conducting several research trials on foot and ankle procedures and trauma surgery. He co-authored a textbook, Core Knowledge in Orthopedics: Foot and Ankle, and numerous peer-reviewed articles that have appeared in professional medical journals. Dr. Greisberg is actively involved in the education of medical students and orthopedic residents and is frequently invited to lecture on complex problems of the foot and ankle at major medical conferences.