Summer J. Decker*, Zackery Beauchamp, and Jonathan M. Ford | University of South Florida Health & Tampa General Hospital Guy Rutty | University of Leicester Abstract: This presentation will discuss the most up-to-date results of our real-world application of using computed tomography (CT)-derived three-dimensional (3D) models of the L1–L5 vertebrae of antemortem CT (AMCT) scans of known individuals and comparing them with postmortem CT (PMCT) scans for personal identification. This presentation expands upon the preliminary results that were previously presented at the 2022 National Institute of Justice Forensic Science Research and Development Symposium. The confirmation of identification for an unknown individual is a critical part of forensic practice especially in disaster victim identification (DVI). The comparison of AM imaging for the purposes of personal identification is a common tool in pathology, odontology, and anthropology. The authors performed a simulated version of this study as a proof of concept of using 3D-rendered lumbar vertebrae comparisons for personal identification.1 The University of Leicester’s East Midlands Forensic Pathology Unit uses PMCT as part of their daily practice and in DVI situations. To date, the University of Leicester has acquired 40 matching AM scans for individuals who passed through their facility for PMCT scanning. The University of Leicester anonymized the scans so researchers at the University of South Florida Health Department of Radiology were blinded to the identities of the AM and PM scans. Each scan was imported into the Mimics® Innovation Suite 24 (Materialise™). The L1–L5 vertebrae were modeled via segmentation and thresholding. Every vertebra was isolated and separated from the most proximal vertebral levels at the superior and inferior facet joints. Each series of 40 antemortem vertebrae were registered with a target unknown PMCT derived vertebra. A part-to-part comparison was conducted for each vertebra, and a match ratio was recorded. A threshold of ±1 mm was set for the part comparison. Every unknown PMCT L1–L5 was correctly matched to the corresponding AMCT L1–L5, signifying complete accuracy for this sample. A receiver operating characteristic curve was calculated to determine 100% sensitivity and specificity with a cut-off point of a 0.73 match ratio. The increased use of clinical CT scans and the growing use of PMCT have allowed for the expansion of means of personal identification in a forensic setting. Reference 1. Decker, Summer J., and Jonathan M. Ford. “Forensic Personal Identification Utilizing Part-To-Part Comparison of CT-Derived 3D Lumbar Models.” Forensic Science International 294 (2019): 21–26. https://doi.org/10.1016/j.forsciint.2018.10.018.