Grant: Doctoral: Vanier Canada Graduate Scholarships

Intraocular cancer is a relatively rare but often deadly disease. In North America, more than 3000 new cases are reported each year. Prior to 1980 the most common form of treatment was enucleation (complete removal) of the eye. However, other treatment methods such as episcleral plaque therapy (EPT), which uses small radioactive sources attached to the eye to deliver cell-killing radiation to the tumour, have been found to produce equivalent survival rates as enucleation for medium-sized tumours, with the added benefit of eye preservation and, for many patients, vision retention. Presently, the method of calculating the amount of radiation delivered to the eye assumes the eye is composed only of water, but this can result in discrepancies of up to 50% in certain eye tissues between the calculated radiation dose and what is actually being delivered. Because of this, the method of calculating the radiation dose is currently undergoing changes to better account for the different materials present in the eye, as well as in the metal eye plaque used to hold the radioactive sources onto the eye. In this project, I will perform high accuracy radiation dose measurements and calculations to better quantify the dose delivered to the different parts of the eye. These results will be compared to those found by different treatment planning software to determine what shortcomings or deficiencies are present in the software that occur from assuming the eye is made entirely of water. This information can then be used to guide further development and improvement of treatment planning systems for EPT, resulting in better treatment outcomes, higher cure rates, and fewer long-term complications for all patients receiving this treatment, both in Canada and abroad.