The Evolving Mcart Multimodal Imaging Core: Establishing a Protocol for Computed Tomography and Echocardiography in the Rhesus Macaque to Perform Longitudinal Analysis of Radiation-Induced Organ Injury.

Computed Tomography (CT) and Echocardiography (EC) are two imaging modalities that produce critical longitudinal data that can be analyzed for radiation-induced organ-specific injury to the lung and heart. The Medical Countermeasures Against Radiological Threats (MCART) consortium has a well established animal model research platform that includes nonhuman primate (NHP) models of the acute radiation syndrome and the delayed effects of acute radiation exposure. These models call for a definition of the latency, incidence, severity, duration, and resolution of different organ-specific radiation-induced subsyndromes. The pulmonary subsyndromes and cardiac effects are a pair of interdependent syndromes impacted by exposure to potentially lethal doses of radiation. Establishing a connection between these will reveal important information about their interaction and progression of injury and recovery. Herein, the authors demonstrate the use of CT and EC data in the rhesus macaque models to define delayed organ injury, thereby establishing: a) consistent and reliable methodology to assess radiation-induced damage to the lung and heart; b) an extensive database in normal age-matched NHP for key primary and secondary endpoints; c) identified problematic variables in imaging techniques and proposed solutions to maintain data integrity; and d) initiated longitudinal analysis of potentially lethal radiation-induced damage to the lung and heart.