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1599 Introduction: The term “spinal cord injury” (SCI) refers to damage to the spinal cord due to trauma, disease, or degeneration. According to the World Health Organization, every year approximately 500,000 people suffer from SCI, with up to 90% of these SCI cases due to trauma. The symptoms of SCI depend upon the severity of the injury and its location in the spinal cord. These symptoms may include partial or complete loss of sensory or motor function. SCI can also affect the system that regulates bowel/bladder control, breathing, heart rate and blood pressure. In this study, we explored the long-term outcomes of a moderate severity SCI in a rat model on glucose uptake throughout the spinal cord. Methods: Adult male Sprague Dawley rats were randomly divided into 2 groups. The injured group received a laminectomy at vertebral level T9 and moderate contusion SCI (150 kdyne force) was induced with Infinite Horizon Impactor (Precision Systems Incorporated, Natick, MA). Sham animals received laminectomy but no impact. PET/CT images were acquired (Siemens Inveon preclinical scanner, Erlangen, Germany) at 4 time points - baseline (prior to injury), 6 hours, 1 month and 3 months post injury for both the groups of animals. FDG uptake was assessed by drawing regions of interest (ROI’s) in the cerebellum, cervical spinal cord (C2-C5, uninjured site) and thoracic spinal cord (injured site), using Siemens Inveon Workplace software (V4.2) [Figure 1]. The Basso-Beattie-Bresnahan (BBB) scale was used to assess neurological function in both the Sham and Injured group at 1, 7, 14, 21, 28 days and 2 and 3 months [Figure 2]. The statistical analysis was done using GraphPad Prism (v8.1), mixed effect model with Sidak’s multiple comparisons tests. Results: The Sham animals showed no significant changes in glucose uptake or motor function at any time point. The Injured group showed impaired functional performance at 1 day and 1-month post injury compared to Sham group. The injured group showed decreased FDG uptake at 1- month and 3- months post injury compared to baseline, not only at the lesion site (thoracic region) but also at the uninjured site (cervical region) [Figure 3 and 4]. Interestingly, the cerebellum also showed decreased FDG uptake at 3- months’ post injury compared to baseline in the injured group of animals but not the shams [Figure 5]. The acute time point (6 hours post injury) did not show any significant alterations. Conclusions: FDG PET can be used to assess moderate spinal cord contusion in rats and indicates decreased glucose uptake up to 3 months post injury at the lesion site and in distal locations possibly suggestive of axonal degeneration. Acknowledgements: This work was supported by the Defense Health Program, Congressionally Directed Medical Research Programs through the Spinal Cord Injury Research Program under Award No. SC170244. Disclaimer: The opinions and assertions expressed herein are those of the author(s) and do not necessarily reflect the official policy or position of the Uniformed Services University or the Department of Defense.