Our Providers



Roger I. Ceilley, M.D.

Dr. Ceilley received his Medical Degree and dermatology residency training at the University of Iowa. He is board-certified in dermatology and dermatopathology and is a fellow of the American College of Mohs Micrographic Surgery and Cutaneous Oncology. He has served as president of the American Academy of Dermatology, president of the American Society for Dermatologic Surgery, and is a diplomat of the American Board of Dermatology. He is the director of our training program in Mohs Surgery and Dermatologic Surgery.

Andrew K. Bean, M.D.

Dr. Bean is board-certified in dermatology. His Medical Degree was earned at the West Virginia University School of Medicine and his dermatology training was completed at Wright State University School of Medicine. He completed an 18-month fellowship in Mohs Micrographic Surgery with Dr. Ceilley and became an associate of Dermatology, P.C. in May 1993. Dr. Bean is a fellow of the American Academy of Dermatology.

Joshua B. Wilson, M.D.

Dr. Wilson is board-certified in dermatology. His Medical Degree was earned at the University of Iowa where he also completed his training in dermatology. Dr. Wilson completed his Mohs surgery fellowship with Dermatology, P.C. under the training of Dr.’s Ceilley and Bean. He is a member of the American Academy of Dermatology and other local and national associations.

Rebecca L. Rovner, M.D.

Dr. Rovner is board-certified in Dermatology by the American Board of Dermatology. She earned her Medical Degree at the University of Iowa and completed her Dermatology Residency at the University of Loyola-Chicago. She is a member of the American Academy of Dermatology and other local and national associations. We welcome Dr. Rovner to Dermatology, P.C. beginning in October 2016.


Mid-Level Practitioners


Amanda Van Wyk, P.A.-C.

Amanda is a state licensed Physician Assistant accredited by the National Commission on Certification of Physician Assistants (NCCPA). She earned a Masters of Science in Physician Assistant Studies from Des Moines University after receiving her Bachelor degree in Biology from Dordt College in Sioux Center, IA. She is a member of the American Academy of Physician Assistants, the Iowa Physician Assistant Society and the Society of Dermatology Physician Assistants. Amanda joined Dermatology P.C. in July 2014.

Amy S. Eschweiler, P.A.-C.

Amy is a state licensed Physician Assistant accredited by the NCCPA. Amy graduated Summa Cum Laude with a degree in Biology from the University of Northern Iowa and also received a Bachelor of Science degree-Physician Assistant from the University of Osteopathic Medicine and Health Sciences. Amy has worked in the Dermatology profession since 1999 and is a member of the following professional organizations: American Academy of Physician Assistants, the Society of Dermatology Physician Assistants, and the Iowa Physician Assistants.

Bianca Patel, P.A.-C.

Bianca is a state licensed Physician Assistant accredited by the National Commission on Certification of Physician Assistants (NCCPA). She earned her Masters of Science in Physician Assistant studies from the University of Nebraska Medical Center after receiving her Bachelor degree in Psychology from the University of Iowa. She is a member of the American Academy of Physician Assistants and the Society of Dermatology Physician Assistants. Bianca joined Dermatology P.C. in February 2018.

Christine Caldwell, P.A.-C.

Christy is a licensed Physician Assistant accredited by the NCCPA. She graduated in 1997 from Des Moines University with a Bachelor of Science in Physician Assistant Studies after completing her Bachelor of Arts in Psychology at Buena Vista College in Storm Lake, Iowa. Prior to joining Dermatology P.C. she worked in family practice. She has over 15 years of clinical experience in various primary care settings. Christy joined Dermatology PC in September 2017.

Elizabeth Hamer, P.A.-C.

Ellie is a state licensed Physician Assistant accredited by the National Commission on Certification of Physician Assistants (NCCPA). She earned her Masters of Physician Assistant Studies from St. Ambrose University after receiving her Bachelor of Science degree in Biokinetics from Bethel University in St. Paul, MN. Ellie is a member of multiple professional organizations and enjoys volunteering throughout the Des Moines area. Ellie joined Dermatology, P.C. in September 2017.

Emily Erickson, P.A.-C.

Emily is a state licensed Physician Assistant accredited by the National Commission on Certification of Physician Assistants (NCCPA). She earned a Masters of Physician Assistant Studies from the University of Iowa after receiving her Bachelor of Arts degree from the University of Northern Iowa. Emily is a member of multiple professional organizations and has also worked as a mentor for pre-Physician Assistant students. Prior to joining Dermatology, P.C. she worked in Urgent Care and Emergency Room settings. Emily joined Dermatology, P.C. in August 2013.

Jennifer A. Vandivier, P.A.-C.

Jennifer is a state licensed Physician Assistant accredited by the NCCPA. She graduated in 2002 from Des Moines University with a Bachelor of Science in Physician Assistant studies after achieving her Bachelor of Science-Nursing from Mount Mercy College. Jennifer has been practicing dermatology in our clinic since that time. Along with her impressive volunteer work, she is an active member of the following professional societies: The Iowa Physician Assistant Society, The American Academy of Physician Assistants, and the Society for Dermatology PA’s.

Megan Ferguson, A.R.N.P., D.C.N.P.

Megan is a state licensed Advanced Registered Nurse Practitioner. She is board certified in Family Practice by the American Academy of Nurse Practitioners (AANP). Megan graduated with highest distinction and honors with her Bachelor of Science degree from the University of Iowa in 2005. She then continued at the University of Iowa to receive her Masters degree as a Family Nurse Practitioner in 2009. She recently obtained her certification as a Dermatology Nurse Practitioner (DCNP) from the Dermatology Nurses Association. She is a member of the American Academy of Nurse Practitioners, Dermatology Nurses Association, and the Society of Dermatology Physician Assistants.

Sonja Baer, P.A.-C.

Sonja is a state licensed Physician Assistant accredited by the NCCPA. She has a Masters degree in Physician Assistant studies from Des Moines University. Sonja also has a Masters degree from Drake University in higher education and a Bachelors degree from Iowa State University in Physical education with a minor in Exercise science. As a Physician Assistant Sonja has worked in Orthopedics and also has 15 years experience as a certified athletic trainer and certified strength and conditioning specialist. She is currently a member of the Society of Dermatology Physician Assistants.

Stacey Ripchinski, P.A.-C.

Stacey is a state licensed Physician Assistant accredited by the NCCPA. She graduated with her Bachelor of Arts degree from Wartburg College and received her Masters of Science in Physician Assistant Studies from Philadelphia University. Her career began in Cardiothoracic surgery before Dermatology became her desired specialty. Stacey is a member of the American Academy of Physician Assistants. Stacey joined Dermatology, P.C. in February 2016.

Tonia K. Ackerman, M.S.N., A.R.N.P.

Tonia is a state licensed Advanced Registered Nurse Practitioner. She is board certified in Family Practice by the American Nurses Credentialing Center. Tonia graduated in 2002 with a Masters of Science degree in Nursing-Family Nurse Practitioner from Clarkson College in Omaha, NE. She also earned her Bachelor of Science in Nursing from Grand View College in 1999, and an Associate degree in Nursing(RN) in 1990 from Marshalltown Community College. She has over 18 years of experience in several areas of nursing. Tonia is a member of the Iowa Nurse Practitioner Society, American Nurses Association, and the Society of Dermatology Physician Assistants.