Isoray Inc offers is a medical technology company. The company designs and develops personalized brachytherapy products that provide more cost-effective cancer treatment. It is engaged in the production and sales of Cesium-131 (Cs-131) brachytherapy seeds. Brachytherapy seeds are small devices containing a therapeutic dose of radiation used in an interstitial radiation procedure. The brachytherapy procedure places radioactive seeds as close as possible to the cancerous tumor. It derives most of its revenue from the United States of America.