Encrypted login | home

Program Information

Adapting An Eye Plaque Into A Small Animal Radiation Research Device

no image available
J Chin

J Chin1*, W Ngwa2, (1) University of Massachusetts Lowell, Lowell, MA (2) Harvard Medical School, Boston, MA


SU-I-GPD-T-31 (Sunday, July 30, 2017) 3:00 PM - 6:00 PM Room: Exhibit Hall

Purpose: Eye plaque brachytherapy is one of the approaches for radiotherapy treatment for ocular cancers: retinoblastoma and choroidal melanoma. This study, investigates the feasibility of using of eye plaques for highly localised/targeted irradiation of tumours when conducting pre–clinical radiotherapy research in animal models.

Methods: The EYE PHYSICS Inc. Plaque Simulator program distributed by IsoAid, LLC, Port Richey, Florida was used. Assuming a mouse with tumour size reaching an average volume of 400 mm³, a simulation to irradiate tumour was conducted to investigate the time taken to deliver a dose of 10 Gy at 5 mm depth below the surface of the skin. Eye plaques are loaded with two different brachytherapy sources I–125 and Pd–103 seeds with the initial activity of 1 mCi/seed in a pattern predicted to be optimal from the simulation. The Plaque Simulator was then used to calculate dose as a function of time for different depths 2mm, 5mm, and 10 mm.

Results: Preliminary results for I–125 show that eye plaques for 5mm depth, the time taken to deliver doses of 5, 10, 20, and 30 Gy were 11.367 hours, 22.800 hours, 45.867 hours, and 69.200 hours respectively. Meanwhile, for Pd–103, the time taken was 15.900 hours, 32.233 hours, 66.350 hours, and 102.567 hours. The times to deliver these doses increased with depth as expected.

Conclusion: The results of this research indicate that eye plaques could be used as pre–clinical radiotherapy device. The use of I–125 seeded eye plaque appears more favorable than the use of Pd–103 given the more reasonable times needed for treatment. Potential applications using such eye–plaques for preclinical research include nanoparticle–aided radiotherapy, combining radiotherapy with immunotherapy, chemotherapy, or motion management studies.

Contact Email: