Small Animal Radiation Research Platform

Contact

Name: Bo Lu, MD, PhD
Position: Project Director, Professor, Director of Div. of Molecular, Radiation Biology & Section of Pulmonary
Organization: Radiation Oncology, Department of Radiation Oncology

Contact

Name: Yan Yu, PhD
Position: Associate Director, Professor, Director of Div. of Medical, Physics, Department of Radiation Oncology

Contact

Name: Dennis Leeper, Karen Knudsen, Matthew Thakur, Jianke Zhang
Position: Advisory Committee

Jefferson Alumni Hall, Room 442

Contact

Telephone: x56705

Contact

Name: Dennis Leeper, PhD
Telephone: x58092

Mission, Goals, Capabilities

The Cone Beam CT Guided Small Animal X-irradiator (SARRP) was purchased by a NIH Shared Instrumentation Grant (S10). It is a novel and highly sophisticated radiation therapy platform that uses a localized, focused beam of x-rays as small as 0.5 mm to irradiate orthotopic or spontaneous tumors, or irradiate targeted normal tissues, while preserving surrounding normal tissues. 

This will allow molecular radiation biology and experimental radiation oncology to be performed in mice with the same precision that is expected in human radiation treatments. This greatly increases the relevance of preclinical animal studies in radiation oncology, the principles of which are used to design radiation treatment regimens for the 50% of cancer patients who receive radiation therapy as part of their management. In addition, this platform will allow organ-specific irradiation to determine tissue-specific biological effects from ionizing radiation. This technology has also been used to ablate brain structures to investigate their physiological functions.

Although the technology for clinical radiation therapy has advanced significantly in the past 25 years, the methods for radiation delivery in a laboratory setting have lagged behind. Modern radiotherapy uses image guidance to deliver highly conformal radiation to a target volume while sparing normal tissue structures. By contrast, up to now methods used in animal research to irradiate spontaneous or orthotopic tumors and their metastases were guided by external features alone, and generally exposed a large portion of the body to radiation. The SARRP has on-board cone beam CT imaging (0.25-0.5 mm voxel size) to guide radiation delivery. It can deliver highly conformal radiation to target volumes with sub-millimeter accuracy. As such, it can precisely irradiate small volumes with a level of precision that approaches current clinical practice. This is especially important to investigate the systemic effects of local radiotherapy (abscopal effects) when radiotherapy is combined with immunotherapy.

Major Equipment

  • Kilovoltage x-ray tube mounted on a 360° rotating gantry and a dose rate of approximately 200 cGy per minute. The tube provides a low-energy beam for cone-beam CT imaging (with a flat panel detector) and a high-energy beam for radiotherapy
  • Focal irradiation of a target volume with sub-millimeter accuracy (0.4 mm)
  • On-board tomographic imaging
  • Volumetric treatment planning to design high-precision pre-clinical irradiation experiments
  • Radiation safety considerations, including interlocks and override shutoffs, lead-lined safety cabinet surrounding the SARRP
  • Dosimetry and calibration equipment
  • Gas anesthesia capability
  • Biosafety level 2 laminar flow hood and associated facilities and supplies

Services

  • Deliver highly conformal radiation to target volumes in the mouse or rat with sub-millimeter accuracy. As such, small volumes can precisely be irradiated with a level of precision that approaches current clinical practice. These volumes may include orthotopic tumors, spontaneous tumors or critical normal tissues targeted for ablation or investigation while sparing surrounding normal tissues.
  • The animal is placed horizontally on a four-axis robotic positioner that provides 360° rotary motion for cone-beam CT with 1 cGy imaging dose, and translation and rotation for radiotherapy targeting.
  • Gas anesthesia
  • Biosafety level 2 environment
  • Images obtained in the Small Animal Imaging Center can be co-registered with those obtained in the SARRP.
  • A highly skilled professional will operate the SARRP.