ASTRO Annual Meeting Thru Wednesday (Colorado Convention Center); IsoRay Medical's New Cesium-131 Radioactive Isotope Seed Offers Aggressive Option for Treatment of Prostate Cancer; FDA Approved for Other Malignant Cancers.

E[acute accent]WHAT:

E[acute accent]IsoRay Medical, Inc., a subsidiary of IsoRay, Inc., (PINK SHEETS:ISRY), is producing a powerful new kind of radioactive, cancer-destroying isotope seed made from Cesium-131 that is implanted directly into tumors. Visit www.cesium131.com or www.isoray.com.

E[acute accent]WHERE:

E[acute accent]Colorado Convention Center. This breakthrough will be in the spotlight at the 47th ASTRO Annual Meeting in Denver, October 16-20 (Booth # 1773). IsoRay Medical executives and physicians who have introduced this brachytherapy option will be available at the booth for media briefings.

E[acute accent]TODAY & TUESDAY:

E[acute accent]An initial report on the use of Cesium-131 for low dose rate (LDR) prostate brachytherapy will be presented at ASTRO by Dr. Bradley Prestidge, MD, Medical Director at the Texas Cancer Clinic. Dr. Prestidge will be available at the IsoRay booth TODAY (October 17) from 1 p.m. to 2 p.m. and on Tuesday, October 18 from 2:30 to 3:30 p.m.

E[acute accent]NOTABLE:

E[acute accent]--Cesium-131 delivers its therapeutic radiation faster than other isotope seeds now being used and at reduced risk to patients when compared to surgery. Introduced in September 2004, the clinical use of cesium-131 marks the biggest advancement in seed brachytherapy (the Greek prefix brachy means short or close) since the introduction of palladium-103 19 years ago.

E[acute accent]--The Food and Drug Administration (FDA) approved Cesium-131 for marketing in March 2003. Its initial use has focused on prostate cancer, but it is approved for other malignant cancers, including head, neck, breast, brain, and liver cancers.

E[acute accent]--Patients at leading cancer treatment hospitals and clinics across the United States are now receiving Cesium-131. The centers for Medicare and Medicaid Services have established a specific reimbursement code for Cesium-131, and most insurance companies also cover the cost of the brachytherapy procedure.

IsoRay Medical, Inc.              877.4.ISORAY
350 Hills Street, Suite 106       509.375.1202 TEL
Richland, WA 99352                509.375.3473 FAX
www.isoray.com
www.cesium131.com

E[acute accent]About IsoRay

E[acute accent]IsoRay, Inc. (PINK SHEETS:ISRY) through its subsidiary, IsoRay Medical, Inc., is the sole producer of the Cesium-131 brachytherapy seed, used to treat prostate and other cancers. The Cesium-131 seed offers a significantly shorter half-life than the two other isotopes commonly used for brachytherapy, which results in a substantially faster delivery of therapeutic radiation and lower probability of cancer cell survival. The Cesium-131 seed has a half-life of 9.7 days, compared to 60 days for Iodine-125 seeds and 17 days for Palladium-103 seeds. Because of this shorter half-life, it delivers more than 90 percent of its total radiation dose in less than 33 days, reducing the incidence of common brachytherapy side effects. IsoRay is based in Richland, Washington. More information is available about IsoRay at www.isoray.com.

E[acute accent]Safe Harbor Statement

E[acute accent]Statements in this news release about IsoRay's future expectations, including: the advantages of our Cesium131seed and all other statements in this release, other than historical facts, are forward-looking statements. It is important to note that actual results and ultimate corporate actions could differ materially from those in such forward-looking statements based on such factors as physician acceptance, training and use of our products, our ability to successfully manufacture, market and sell our products, our ability to manufacture our products in sufficient quantities to meet demand within required delivery time periods while meeting our quality control standards, and our ability to enforce our intellectual property rights, and other risks detailed from time to time in IsoRay's reports filed with the SEC.