Whole animal imaging

Abstract

Translational research plays a vital role in understanding the underlying pathophysiology of human diseases, and hence development of new diagnostic and therapeutic options for their management. After creating an animal disease model, pathophysiologic changes and effects of a therapeutic intervention on them are often evaluated on the animals using immunohistologic or imaging techniques. In contrast to the immunohistologic techniques, the imaging techniques are noninvasive and hence can be used to investigate the whole animal, oftentimes in a single exam which provides opportunities to perform longitudinal studies and dynamic imaging of the same subject, and hence minimizes the experimental variability, requirement for the number of animals, and the time to perform a given experiment. Whole animal imaging can be performed by a number of techniques including x-ray computed tomography, magnetic resonance imaging, ultrasound imaging, positron emission tomography, single photon emission computed tomography, fluorescence imaging, and bioluminescence imaging, among others. Individual imaging techniques provide different kinds of information regarding the structure, metabolism, and physiology of the animal. Each technique has its own strengths and weaknesses, and none serves every purpose of image acquisition from all regions of an animal. In this review, a broad overview of basic principles, available contrast mechanisms, applications, challenges, and future prospects of many imaging techniques employed for whole animal imaging is provided. Our main goal is to briefly describe the current state of art to researchers and advanced students with a strong background in the field of animal research.

Real-time recording of circadian liver gene expression in freely moving mice reveals the phase-setting behavior of hepatocyte clocks

“…Both of these techniques have been successfully adapted to whole-body imaging of mice (Hoffman and Yang 2006;Sandhu et al 2010). Fluorescence measurements involve the excitation of fluorescent proteins with bright light, which would phase-shift the SCN (Albrecht et al 2001).…”

Advances in image-guided Intratumoral Drug Delivery Techniques

“…Despite these advances, owing to the high level of expertise required for clinicians to successfully administer therapeutics via CED [108], as well as the high cost and exposure limitations inherent in MRI and CT [109], widespread use of the technique is currently limited.…”

Identification of muscle necrosis in the mdx mouse model of Duchenne muscular dystrophy using three-dimensional optical coherence tomography

“…20,21 The ability to conduct in vivo 3D tissue analysis of an individual animal over time is attractive. The performance of high-resolution systems (∼30 to 40 μm) 29 is approaching that required to image individual myofibers, but access, cost, and the long acquisition times of MRI remain challenges impeding the uptake of this imaging modality for studies of mouse models of DMD.…”