Xstrahl In Action: Model for Precise and Uniform Pelvic- and Limb-Sparing Abdominal Irradiation For Study
Accidental high-dose radiation exposure can result in mortality or severe morbidity through acute radiation syndrome (ARS). The early risk of death from ARS can be attributed mainly to radiation-induced gastrointestinal syndrome (RIGS). Currently, there are no readily available pharmacological agents that offer effective mitigation of RIGS, and as such there is great interest in developing such mitigators.
To study the radiation-induced gastrointestinal syndrome and the development of potential medical countermeasures to mitigate the effects of radiation exposure Brodin N.P., Velcich A., Guha C and Tomé W.A. in their study “A Model for Precise and Uniform Pelvic- and Limb-Sparing Abdominal Irradiation to Study the Radiation-Induced Gastrointestinal Syndrome in Mice Using Small Animal Irradiation Systems” presented an animal model for precise and homogenous limb-sparing abdominal irradiation (LSAIR).
The LSAIR technique was developed using the Xstrahl Small Animal Radiation Research Platform (SARRP). The SARRP consists of an X-ray tube mounted on a rotatable gantry capable of delivering a maximum X-ray energy of 220 kVp at 13-mA tube current, either as an open field or as a collimated field using a set of custom collimators. The image guidance capabilities of the SARRP consist of a high-resolution amorphous Si flat panel detector for cone-beam computed tomography imaging and a foldout portal imager for X-ray fluoroscopy. Animals are placed on a robotic stage providing 4 degrees of freedom for targeted alignment of the radiation delivery.
LSAIR was delivered at doses between 14 and 18 Gy on 8- to 10-week-old male C57BL/6 mice. Total of 111 animals were irradiated to 14 (n = 4), 15 (n = 10), 15.5 (n =10), 16 (n = 15), 16.5 (n = 16), 17 (n = 16), 17.5 (n = 18), or 18 Gy (n = 22). Irradiation experiments were performed in separate sessions to ensure that the results were reproducible. Irradiated mice were then followed for survival to determine the dose–response relationship and kinetics of RIGS-induced mortality. Histological analysis was performed to confirm that the observed mortality was due to acute abdominal radiation injury.
The authors reached a conclusion that the developed LSAIR technique provides uniform dose delivery with a clear dose response, consistent with acute abdominal radiation injury on histological examination. This model can provide a useful tool for researchers investigating the development of mitigators for accidental or clinical high-dose abdominal irradiation.