Dr. Cronin

Dr. Hyland Cronin is a board-certified dermatologist and board-certified Mohs micrographic surgeon. She is a specialist in skin cancer, reconstructive surgery, and laser procedures.

She graduated Summa Cum Laude at the University of Notre Dame and she received her medical doctorate degree from the West Virginia University School of Medicine. She completed her Internal Medicine Internship at Loyola University and her Dermatology Residency at Geisinger Health System. Following her residency, she completed a fellowship in Mohs Micrographic Surgery in 2010 under the direction of renowned Dr. Glenn Goldstein at The Dermatology and Skin Cancer Center in Leawood, KS. Dr. Cronin, is a Mohs College graduate, having done the extra one-year fellowship training program in skin cancer surgery, pathology, and advanced reconstructive surgery.

By virtue of her rigorous fellowship, she possesses the skills and experience necessary to perform Mohs Micrographic Surgery and reconstruction at all levels of complexity. She is a board-certified dermatologist, a board-certified Mohs micrographic surgeon, a diplomate of the American Academy of Dermatology and a fellow of the American College of Mohs Micrographic Surgery and Cutaneous Oncology (www.mohscollege.org).

Laser technology has grown to effectively address a broad range of skin conditions. At Cronin Dermatology and Skin Cancer Center, Dr. Cronin and staff are educated and experienced in the use of this technology to treat skin conditions and cosmetic concerns, resulting in more refreshed, youthful-looking skin. The expertly administered laser treatment you receive reduces or eliminates the appearance of birthmarks, acne, brown spots, wrinkles, scars and more, to help you feel better about your skin’s health and your appearance.

She is also an active member of the American Society for Dermatologic Surgery and Women’s Dermatologic Society. In addition, she is the current  president for the Washington Dermatologic Society. She was honored by receiving 2021 & 2022 Top Doctors in the Washingtonian and Bethesda Magazine’s 2021 Top Doctors both chosen by her peers.


Dr. Cronin Specializes in the following services:

  • Cancer (Basal Cell, Squamous Cell and Melanoma)
  • Atopic Dermatitis
  • Eczema Psoriasis
  • Rosacea
  • Acne
  • Skin Tags
  • Sun Damaged Skin
  • Aging Skin
  • Cysts Folliculitis
  • Hair Loss (PRP)
  • Infections of Skin and Nails
  • Keloids
  • Seborrheic Keratoses Stasis Dermatitis
  • Leg Ulcers
  • Urticaria
  • Warts
  • Vitiligo
  • Actinic keratosis (Cryosurgery) and Actinic damage (Blue light photodynamic therapy)
  • seborrheic keratosis
  • stasis dermatitis
  • Itchy Skin
  • BOTOX® and fillers (including Restylane®, JuvedermVoluma®, RHA)
  • Laser Hair Removal
  • Profound Laser
  • Microneedling
  • VBeam Pulsedye Laser
  • Sciton Joule X
  • BBL/IPL
  • Profractiona
  • Skintyte
  • Micropeel
  • NanoPeel
  • Halo Fractional Laser
  • Acne Laser

Cassandra Rullman, PA-C

Cassandra Rullman, PA-C has been practicing in Dermatology since graduating from PA School. She has been trained in dermatology and cosmetics exclusively, and has become highly skilled in managing a variety of common and uncommon dermatologic disorders and skin cancers. She joined the team at Cronin Dermatology and Skin Cancer Center after practicing in Atlanta for years.
Cassandra has personally struggled with skin conditions throughout her life, which initially sparked her interest in the field of dermatology. Through these experiences her passion for dermatology and the complex interactions between health and wellness, and their impact on the skin grew. Cassandra strives to use her personal experience with her own skin conditions to form a personal connection with her patients. Cassandra aspires to go beyond what is visible on the skin when evaluating her patients and when determining a treatment plan. She enjoys serving patients of all ages and seeks to develop an individualized relationship with each patient.

Cassandra Rullman, PA-C grew up in the Annapolis area and graduated Magna Cum Laude from The Pennsylvania State University. For PA School Cassandra returned home to Maryland and graduated first in her class from the University of Maryland, Baltimore. She is a current and active member of Phi Alpha Physician Assistant Honor Society, the Society of Dermatology Physician Assistants, and the American Academy of Physician Assistants.