Our Team

All our professionals maintain the highest levels of accreditation and pursue ongoing education to stay abreast of the latest trends in the medical field. Read on to learn more about our staff's experience and training.

Board Certified Dermatologists

Thomas Casey Gallagher, MD

Board Certified Dermatologist

Dr. Gallagher is board-certified in dermatology and is a board-certified Mohs surgeon. He is a member of the Boulder County Medical Society and a fellow of the American Academy of Dermatology, the American Contact Dermatitis Society, and  the American Medical Association.

Dr. Gallagher graduated Phi Beta Kappa and magna cum laude from Harvard University. Dr. Gallagher completed medical school and his internship at the University of California, San Francisco, where he received the UCSF-Reiner International Health Research Fellowship, and a fellowship from the American Medical Student Association for a research project in Kenya. While in medical school, he organized and led a medical outreach trip to the Bolivian Andes.

Dr. Gallagher then completed his dermatology residency at New York University (NYU), where he received extensive training in medical, surgical, pediatric and cosmetic dermatology.

After his residency, Dr. Gallagher was appointed Assistant Professor in the Department of Dermatology at NYU. His duties included training dermatology residents and serving as Director of the Residency Selection Committee. Additionally, Dr. Gallagher maintained a busy private practice with NYU’s Dermatology Faculty Practice. He also co-founded the only free clinic for uninsured patients in Manhattan and received university recognition for this contribution to community health.

Dr. Gallagher relocated to Colorado to co-found Boulder Valley Center for Dermatology. He has published work in peer-reviewed medical journals and a dermatology textbook. He has appeared on local radio and in the local press to speak about medical and cosmetic dermatology. In 2023, he was selected by Castle Connolly Top Doctors, featured in 5280’s Denver’s Top Doctors, August 2023 edition. He also serves as the dermatology contributor on the Medical Review Board of About.com and is a Medical Expert Board Member https://www.verywellhealth.com/casey-gallagher-md-4685028 for Very Well Health https://www.verywellhealth.com/.

Dr. Gallagher has served on the Board of Directors for many local organizations, including the Boulder Valley Independent Practice Association, the Boulder County Medical Society, and the Colorado Medical Society.

Dr. Gallagher has completed his board certification in MOHs surgery as established by the American Board of Dermatology and includes residency training in an accredited program and successful completion of the certifying examination.

Dr. Gallagher is married with two sons. He enjoys community service, hiking, running and playing bridge. He is fluent in Spanish.


Mary Katherine (“Katie”) Hill, MD

Board Certified Dermatologist

Dr. Hill is a board certified dermatologist, born and raised in Westminster, Colorado. She graduated magna cum laude from the University of Notre Dame with a degree in Accountancy and Latin. Dr. Hill then graduated from the University of Colorado School of Medicine with Alpha Omega Alpha honors. She completed an Internal Medicine internship at St. Joseph Hospital in Denver, where she received the “The Sam Ferszt Time Stands Still Award,” acknowledging her exceptional dedication to quality patient care.

Dr. Hill served as Chief Resident at the University of Colorado Dermatology Residency program, where she trained at the University of Colorado HospitalDenver Health HospitalChildren’s Hospital Colorado, and Rocky Mountain Regional VA Medical Center. Dr. Hill also served as the resident leader of the DAWN Dermatology Clinic for the Underserved, a free clinic for the uninsured population of Aurora and Denver.

Dr. Hill is a member of the American Academy of DermatologyColorado Dermatologic Society, and Women’s Dermatologic Society. She has published multiple peer-reviewed medical articles, and presented at various national and local conferences, including the American Academy of Dermatology and Colorado Dermatologic Society annual meetings.

Dr. Hill is thrilled to be a part of the Boulder Valley Center for Dermatology team of providers. She is a thoughtful, compassionate physician who truly values developing life-long relationships with her patients. Dr. Hill continually strives to provide the highest level of medical care, and is committed to staying up to date on new evidence-based treatments.

Dr. Hill is married with a daughter. She and her husband are very happy to be in Colorado with their families. In her free time, Dr. Hill enjoys spending time with her family and dog, hiking, biking, snowshoeing, and any other activity involving the great Colorado outdoors.

Physician Assistants

Ryan Bird, PA-C, MPAS

Physician Assistant

Ryan joined Boulder Valley Center for Dermatology in 2014 after graduating magna cum laude from Marquette University where he earned a Master of Physician Assistant Studies (MPAS). Ryan was born and raised in Arvada, Colorado and he completed his undergraduate studies at the University of Colorado with a BA in integrative physiology.

He initially developed a passion for dermatology after working as a medical assistant at Boulder Valley Center for Dermatology from 2010-2011, returning in 2014 to serve our community in a new capacity as a Physician Assistant. Ryan places a strong emphasis on delivering individualized patient-centered care, while focusing on medical and surgical dermatology.

Although he has been with Boulder Valley Center for Dermatology for a decade, he continues to stay up to date with the newest advancements in dermatology, prioritizing evidence-based medicine. Ryan is married and has a young daughter. Outside of work, he enjoys spending time with his family, maintaining a healthy and active lifestyle, traveling, and taking on home projects.

Brooke Weinberger, PA-C, MPAS

Physician Assistant

Brooke graduated from the University of Colorado with a Master’s in Physician Assistant Studies. She is a certified Physician Assistant by the State of Colorado and the National Council for the Certification of Physician Assistants.

Brooke grew up in Wilmington, NC and attended Davidson College, where she majored in Spanish. Brooke also earned a Master’s degree in Spanish from University of Colorado at Boulder and is a fluent Spanish speaker.

Brooke is married with two sons and loves to spend time outdoors with her family hiking, skiing and biking. She also enjoys cooking, reading and playing soccer.

Brooke is excited for the opportunity to expand her professional career as a Physician Assistant at Boulder Valley Center for Dermatology, helping patients care for their skin in our beautiful, high altitude Colorado climate.

Zoey Crane, PA-C, MPAS

Physician Assistant

Zoey has been an essential part of the BVCD team since 2019. She is a graduate of the Physician Assistant Program at the University of Colorado’s School of Medicine where she received her Master of Physician Assistant Studies. She now helps educate PA students at CU by providing lectures during their dermatology training.

Prior to attending PA school, Zoey graduated from University of Virginia where she majored in Biology and Bioethics.

Zoey loves providing high quality medical dermatology care to patients of all ages and backgrounds. She has a passion for taking the time to form lasting relationships with her patients, performing thorough skin cancer screenings and making patients feel more comfortable in their skin by helping manage a wide variety of acute and chronic skin conditions.

Additionally, Zoey speaks fluent Spanish as she spent her childhood growing up overseas in many countries including Guatemala and El Salvador.

In her free time Zoey enjoys hiking, skiing, traveling, cooking, and spending quality time with family and friends.

Alanna Thomas, PA-C, MS

Physician Assistant

Alanna is a graduate from Georgia-Philadelphia College of Osteopathic Medical School where she received her Master’s of Science Degree in Physician Assistant Studies. Her undergraduate degree is from Quincy University where she majored in biology and minored in chemistry. Alanna has previously worked in hematology and oncology at practices in Georgia and Colorado.

Alanna grew up living in Illinois and is married and has a dog. She enjoys Colorado and likes to hike, ski, and play pickleball. Alanna is excited to expand her professional career at Boulder Valley Center for Dermatology

Trevor Fleischmann, PA-C, MPAS

Physician Assistant

Trevor is a graduate from Springfield College where he received his undergraduate degree in Sports Biology with a minor in chemistry and ultimately his Master’s of Science Degree in Physician Assistant Studies. He has previously worked as a nocturnist physician assistant in Connecticut.

Trevor grew up living in Connecticut but is excited for a new adventure and career in Colorado. He likes to hike, bike, snowboard, fish and spend quality time with family. Trevor is excited to expand his professional career at Boulder Valley Center for Dermatology

Colton Wright, PA-C, MPAS

Physician Assistant

Colton graduated with his Master’s degree in Physician Assistant Studies from the University of the Cumberlands in Williamsburg, Kentucky.

He received his undergraduate degree in Healthcare Administration with a minor in Biochemistry from Carroll University in Waukesha, Wisconsin.

Originally from Roscoe, Illinois, Colton is excited about the wonders of Colorado. He loves to be active and enjoys engaging in various outdoor hobbies, as well as spending time with family and friends. Colton takes pride in providing empathetic, patient-centered care and is eager to make a positive impact on the community.

Elena Lopez

Cosmetic Supervisor Laser Certified Aesthetician

Elena is a licensed aesthetician and laser specialist with over 20 years of hands-on experience. Driven by her passion for meticulous work and results, Elena partners with patients to cultivate personalized treatment plans.

As a Denver native, Elena has personal knowledge of how the changes in weather and high altitude can affect one’s skin. She is accomplished in working on all skin types and furthers her expertise and job knowledge through continuing education and staying up to date with aesthetic technology. Elena then passes her knowledge onto her patients, so they are well informed throughout their skin journey.