Orthovoltage is a type of radiation therapy that has been available for more than 60 years. The X-rays used in this treatment are strong enough to kill cancer cells but do not penetrate more than a few millimeters beyond the surface of the skin, making it an effective treatment for very superficial, small tumors, such as skin cancers and non-malignant skin conditions such as keloids. Orthovoltage is an excellent non-invasive alternative to surgery for skin cancer in sensitive locations, such as the folds of the nose, eyelids or ears.


No special preparation is required prior to having orthovoltage. However, the skin should be clean and free of any heavy lotions or makeup.


At your first session, a small fitted shield made of lead will be customized for you. The shield is designed with an opening in the middle where the skin will be treated. The shield is used during all of the treatments to protect the healthy normal tissues surrounding the targeted area.

After the first session during which your lead shield is designed, actual treatments are usually started the following business day. Treatments are painless and take about 15 minutes. You will receive orthovoltage every day for a period of three to four weeks.

During treatment, the technician and doctor will position you lying down on the table in a comfortable and reproducible way. You will be positioned so that the orthovoltage machine with the proper size cone attachment can be placed over the open area in the lead shield.


In general, you will feel only minimal side effects after orthovoltage. Because it is a very focused and superficial treatment, confined only to the surface of the skin, most patients continue to work or perform all of their normal activities as usual the same day.

It is important to be very gentle with your skin during treatment and for a few weeks afterwards. Avoid scrubbing the treated area or shaving in a way that will nick or tear the skin. Some patients experience reddening, tenderness or sensitivity of the treated skin area.

For the rest of your life, you should avoid excessive sun exposure to the treated area or use a high SPF sunscreen if sun exposure cannot be avoided.


Reviewed by health care specialists at UCSF Medical Center.

Related Information

UCSF Clinics & Centers

Radiation Oncology at Mount Zion
1600 Divisadero St., Basement Level
San Francisco, CA 94143-1708
Main Phone: (415) 353-7175
New Patient Appointments: (415) 353-9807
Fax: (415) 353-9884

Radiation Oncology at Parnassus
505 Parnassus Ave, Room L-75
San Francisco, CA 94143-0226
Main Phone: (415) 353-7175
New Patient Appointments: (415) 353-8335
Fax: (415) 353-7281

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