Ambulatory
Hicham Ibrahim, M.D.
Vice President and Senior Executive Officer of Ambulatory Services
Hicham Ibrahim, M.D., M.B.A., was named Vice President and Senior Executive Officer of Ambulatory Services in September 2024. In this role, he leads strategies and oversees operations for more than 80 UT Southwestern outpatient clinics throughout North Texas.
Dr. Ibrahim is a Professor of Psychiatry and previously held roles as Associate Vice President and Chief Medical Officer, Vice Chair for Clinical Affairs in the Department of Psychiatry, and Chief of Psychiatry of the Mental Health service at the Dallas Veterans Affairs Medical Center.
Dr. Ibrahim has been repeatedly selected by his peers for inclusion in Best Doctors in America since 2011. He has won numerous institutional and national teaching awards including the American Psychiatric Association’s Irma Bland Award for Excellence in Teaching Residents and Nancy Roeske Award for Excellence in Teaching Medical Students. In 2019, under Dr. Ibrahim’s leadership, the Outpatient Psychiatry Multi-Specialty Program received UT Southwestern’s Leaders in Clinical Excellence Program Development Award.
Additionally, he has published peer-reviewed articles in top professional journals such as American Journal of Psychiatry and Annual Review of Pharmacology and Toxicology, given invited presentations at national scientific meetings, and served as a reviewer for several professional journals.
Dr. Ibrahim completed his medical education at the American University of Beirut and his residency in psychiatry at the University of Michigan Medical Center and UT Southwestern. He also completed a research fellowship in neuroscience at the University of Michigan, two clinical fellowships in addiction and geriatric psychiatry at UT Southwestern, and a Master of Business Administration at the University of Texas at Dallas.
Toni Eby, M.B.A., RN
Associate Vice President and Chief Operating Officer of Ambulatory Services
Toni Eby, M.B.A., RN, joined UT Southwestern in October 2021 as Associate Vice President and Chief Operating Officer of Ambulatory Services. Ms. Eby provides oversight for operations across UT Southwestern’s more than 80 outpatient clinics and implements strategies that advance high-quality care within programs and services.
Since joining UT Southwestern, Ms. Eby has overseen the integration of clinical programs across Ambulatory Services to ensure the continuity of care and standards for all sites of service. She works closely with department chairs, medical directors, clinic managers, and other leadership to improve patient access and build on our efforts to provide exceptional team-based, multidisciplinary care.
Before joining UT Southwestern, Ms. Eby held executive leadership roles at large health care organizations across the country, including MD Anderson Cancer Center, where she worked for 14 years.
Ms. Eby earned a Master of Business Administration from the University of Houston-Victoria.
Nisa Kubiliun, M.D
Associate Vice President and Chief Medical Officer for Ambulatory Services
Endowed title: Nancy and Jeremy Halbreich Professorship in Cancer Prevention, in Honor of Nisa Kubiliun, M.D.
Nisa Kubiliun, M.D., was appointed Associate Vice President and Chief Medical Officer of Ambulatory Services in March 2025. Dr. Kubiliun provides oversight for operations at more than 80 outpatient clinics at UT Southwestern to ensure the highest level of multidisciplinary care across the enterprise. In her role as CMO, she partners with other executive leaders on strategies to advance quality and performance, and to expand care across the region.
Dr. Kubiliun earned her medical degree from the University of Miami Miller School of Medicine. She completed a residency in internal medicine at UT Southwestern in 2006. After gaining advanced training through a fellowship in gastroenterology at the University of Miami, Dr. Kubiliun pursued an interventional endoscopy fellowship at the University of Michigan.
With three years of general gastrointestinal training and an additional year of interventional training, Dr. Kubiliun is uniquely positioned to offer comprehensive care for pancreaticobiliary cancers. She serves as medical director of the Pancreatic Cancer Prevention Program and has authored numerous impactful articles in peer-reviewed journals.
Diane Woods, M.S.N., RN, NEA-BC
Associate Vice President and Chief Nursing Officer of Ambulatory Services
Diane Woods, M.S.N., RN, NEA-BC, joined UT Southwestern in 2025 as the Associate Vice President and Chief Nursing Officer of Ambulatory Services. She oversees all levels of nursing practice at 80-plus UT Southwestern outpatient settings across the region to ensure uniform care excellence. In coordination with other nursing and Health System leaders, Ms. Woods spearheads initiatives to promote top-of-license practice, professional development, and advances in the patient experience.
Ms. Woods is a highly accomplished nursing leader and ambulatory care executive. Before joining UT Southwestern, she held executive leadership roles at UC Davis Health (University of California) and the Emory Physicians Group practice in Atlanta, Georgia, where she successfully implemented initiatives that optimized care models for efficiency and enhanced safe, timely, high-quality patient care.
Ms. Woods received her nursing diploma from St. Mary’s School of Nursing and the University of Tennessee and her Master of Science in Nursing from Chamberlain University College of Nursing in Chicago. She is board certified as an Advanced Nurse Executive by the American Nurses Credentialing Center.