BACKGROUND:  In the United States, the probability of developing an invasive cancer is approximately 1 in 3. Conventional external radiation therapy often damages other tissues and sensitive areas like the spinal cord and brain. Internal radiation therapy (IRT), offers the major advantage of minimizing exposure to surrounding tissues. IRT is now used as a treatment for breast, prostate, cervical, head, neck, liver, and lung cancers. In cardiology, IRT can be used to prevent artery closure after removal of plaque, and to stop blood clots from forming. Existing IRT methods insert "seeds," or radioactive isotopes, into organs via a catheter. This methodology is clumsy, limited to a fixed dosage rate, cannot be turned on and off, and may cause problems if seeds migrate. Miniature x-ray tubes can be used instead, but operate only over a non-specific, low energy (10-50 keV) range. Novel cancer therapies are continuously being sought, and the need for advancements in IRT is clear.

INNOVATION:  UCLA scientists have developed a novel laser light activated medical device that can deliver controlled amounts of ionizing radiation directly to a source. Laser light is produced in the treatment room and transmitted via fiber optic cable down the catheter to an accelerator. The accelerator then produces and accelerates electrons into the organ of interest. Radiation dose can be dynamically controlled by varying the pulse frequency of the laser. This invention can achieve energy ranges not currently available by any commercial medical device (1-3 MeV), and represents a major breakthrough in radiation oncology.

POTENTIAL APPLICATIONS 

• Vascular IRT:
• - Preventing artery closure after removal of plaque

  - Prevent late stage clots from forming in cardiac stents coated pharmaceutically

  Radiation Oncology as treatment, and following removal of tumors:

  - Breast, prostate, cervical, head and neck, and lung cancers

  Stereotactic Radiosurgery

  Arteriovenous malformations in the brain

ADVANTAGES

• Precise control over radiation dose, administration time, penetration depth, and pulse energy
• High Energy Range attainable:
• - 1-3 MeV- significantly higher than permitted by current commercial products

  Energy and penetration depth of the radiation can be known precisely.

DEVELOPMENT-TO-DATE:  Computational simulations and calculations have been performed.

Reference: UCLA Case No. 2007-412