Novel 125I Uniformly Distributed Ophthalmic Plaques

DESCRIPTION (From the Applicant's Abstract): Brachytherapy seed eye plaques are commonly used in the treatment of ocular melanomas and macular degeneration. In addition to being relatively bulky, the dose distribution generated by the seed cores is non-uniform and highly complex. With the non-spherical iso-dose radiation profiles of each seed and variations in individual seed activities, it is an extremely involved and difficult process to accurately calculate the radiation dose rate at varying points within the eye and even within the tumor. A plan is proposed in which a novel uniformly distributed radioactive plaque is fabricated. The plaque shall consist of an 125I ion implanted thin foil attached to a 0.5 mm thick gold protective shield. The gold shield shall also act as a radiation collimator to protect normal structures located at the periphery of the plaque. A spacer will be used to seal the radioactive source. This plaque would provide accurate radiation dosimetry and would be three times thinner than current eye plaques. Tumor irradiation plans using such a plaque would optimize the dose to the tumor while minimizing the dose to normal ocular structures resulting in an significant decrease in radiation induced ocular complications. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE