Featured Article for January 31, 2022
Radiation Optic Neuropathy
There is no specific radiation dose that has been deemed safe to avoid RON, but in general some radiation parameters have been proposed. In general, if the total fractionated radiation dose is less than 5,000 centigrays (cGy), then RON is rare. If stereotactic radiosurgery (e.g. Gamma knife) is performed, single radiation doses of 800 to 1,000 cGy at a time (usually 1-3 sessions) are considered relatively safe. Radiation doses from 5,000 – 6,000 cGy may produce RON with a risk of up to 5% within 10 years. Most RON, however, will present within 3 years of radiation treatment with a peak incidence after 1.5 years.
