Coralline hydroxyapatite spheres are used as buried integrated ocular implants after enucleation or evisceration surgery. Because such implants are used after surgery for intraocular malignancy and because some patients may require postoperative radiation therapy for orbital tumor recurrence, the radiation attenuation characteristics of the implant are of interest. The authors evaluated the attenuation and scattering properties of coralline hydroxyapatite implants using a 4 MV photon beam and film dosimetry. Optical density analyses indicate that coralline hydroxyapatite implants have no significant influence on the attenuation or scattering properties of the photon beam. As such, there is no basis for concern that such implants might adversely affect external beam photon irradiation.