
<b>Eyes</b>

The eye's sensory retina, as well as other central nervous system tissues, is highly resistant to radiation damage. But the retinal blood vessels are extremely sensitive to radiation damage, producing damage to the retina that is like the damage from other diseases that obliterate the blood supply. In one study, radiation retinopathy [damage to the retina] occurred in 63% of patients who had orbital irradiation,  and 36.3% who had periorbital irradiation. The first group had damage appearing earlier, with greater involvement, and also had three cases of glaucoma developing. Care must be taken when irradiating periorbital structures as well. 