Mohs Micrographic Surgery is a highly specialized procedure for the total removal of skin cancers under microscopic control. Because each layer is examined microscopically, dermatologists can be reasonably certain that all of the cancer has been eradicated while saving as much normal skin as possible, and resulting in the highest rate of cure.

Dr. Tanya Riddle is a member of the American Society of Mohs Surgery, and is a fellowship-trained, triple board certified dermatologist. She has three board certifications in dermatology, dermatopathology, and micrographic dermatologic surgery (Mohs surgery).

Last year Dr. Riddle performed over 400 cases of Mohs surgery at Billings Dermatology & Aesthetics. Our Mohs patients come to us from a wide geographical area, spanning Montana, Wyoming, North Dakota and South Dakota. We are committed to ensuring our local and regional patients are provided the highest quality of medical and surgical care, excellence in customer service, and warm hospitality during their procedure.

Frequently Asked Questions regarding Mohs Micrographic Surgery

What is Mohs surgery?

Mohs surgery is a type of skin cancer surgery that enables the surgeon to remove all of the cancer, in several stages, without removing too much healthy tissue. This type of surgery is also called ‘micrographic surgery’, which means that a microscope is used to examine what is being done during the procedure.

When is Mohs surgery necessary?

Mohs micrographic surgery is especially effective in cancers of the face and other cosmetically sensitive areas, because it can eliminate virtually all the cancer cells while causing minimal damage to the surrounding normal skin. The procedure is also ideal for the removal of recurrent skin cancers, in addition to skin cancers which have poorly defined clinical margins.

What is the advantage of Mohs surgery over other treatments?

With a 98-99% success rate, Mohs surgery is the most effective treatment available. The procedure creates the smallest possible defect; therefore, allowing for the best possible cosmetic result.

What does Mohs surgery involve?

Mohs procedures are considered minor surgeries and are performed in our office. Although the procedure typically takes three to five hours, patients should be prepared to spend the entire day if necessary. The surgery is usually performed in stages, with each stage taking approximately 15 minutes to one hour. The stages include the removal of the cancerous tissue and reconfirmation of complete removal of the tissue. The number of stages required varies with each patient and is determined by the size and depth of the cancer.

What should I do before surgery?

Be sure to eat a full, healthy meal and bring reading material if you like. You may bring a snack if you wish; because you will have waiting periods between surgical stages. We will have deli sandwiches delivered for our Mohs patients at 11am on Mohs Surgery days; please let staff know if you would like one.

What should I wear?

You are encouraged to wear comfortable clothing, and if you are easily chilled we recommend you bring a warm sweater or a blanket.

What about my medications?

Please consult your primary care physician before stopping any medications. Also, please avoid alcoholic beverages one week before surgery.