Dosimetry study of an accidental overexposure to 192Ir gamma rays.

Localized irradiation of the skin and subcutaneous tissues with large single doses of gamma rays can induce delayed effects characterized by fibrosis that invades the irradiated tissues. The skin surface dose and the depth of penetration of 192Ir gamma rays, measured in phantoms and in frozen thighs of sacrificed pigs after acute single doses of irradiation and different skin-to-source distances, are reported in this note. Correlations between the dosimetry and the evolution of the lesions are considered.