1.  The normal zebrafish had 2.3 degree incline from horizontal from the head through the first 7 vertebrae (Figure 1)  Following the 7 th vertebrae the normal zebrafish has two points of curvature (Figure 1) - After the 7 th vertebrae a 10 degree decline - After the 14 th vertebrae a 5 decree decline  The zebrafish with spinal deformities had three large points of curvature (Figure 2) - At the 8 th vertebrae spine curves 42 degrees ventrally - At the 14 th vertebrae spine curves 92 degrees posteriorly - At the 18 th vertebrae spine curves 120 degrees dorsally  Zebrafish with spinal deformities had curvatures that encompassed all three planes  Surprisingly, the zebrafish with spinal deformities had fins fused to the facets (Figure 2d) 3D GEOMETRIC MODEL OF ZEBRAFISH TO STUDY SPINAL DEFORMITIES USING CT IMAGING Blake Johnson 1 MS, Henry Tomasiewicz 2 PhD, Naira Campbell-Kyureghyan 3 PhD Bioengineering Imaging and Testing Laboratory, University of Wisconsin Milwaukee, Milwaukee, WI 1 Graduate Student; 2 Associate Scientist, 3 Faculty Advisor INTRODUCTION METHODS RESULTS DISCUSSION  A wide variety of species have been used to study spinal deformities [1]  No previous studies addressed the 3D morphology or researched how spinal deformities in zebrafish affect its function  The goal of this research is to reconstruct and compare 3D geometric model of the musculoskeletal structure of a zebrafish with spinal deformities to a zebrafish without spinal deformities via computed tomography (CT)  From a previous study, spinally deformed zebrafish were obtain through crossing a normal zebrafish with a founder fish [2]  The normal and spinally deformed zebrafish were euthanized and placed on the manufacturer specified test mount  Both fish were scanned using a Zeiss Xradia Versa 410 MicroCT (San Jose, CA) with the power and voltage set at 10 Watts and 40 kV  CT images were reconstructed and analyzed using Zeiss XM Reconstructer and XM3D Viewer (San Jose, CA)  Images were then transferred to Mimics v17 by Materialize (Plymouth, MI) for further analysis  Spinal curvatures for both fish were measured by taking the angle at the intersection of lines drawn parallel with the center of each vertebrae Figure 1: Normal zebrafish position with head facing to the left a.) lateral view b.) ventral view c.) dorsal view d.) close up of vertebrae and fin interaction (arrows highlight gap between vertebrae and fins) Figure 2: Zebrafish with spinal deformities positioned with head facing to the left a.) lateral view b.) ventral view c.) dorsal view d.) close up of vertebrae and fin interaction (arrows indicate points of attachment)  The fusion between fins and facets could cause dynamic instability - Fins provide dynamic stability during locomotion but fish require full control of the fin shape and area [3]  Altered geometry of the spine can change the center of buoyancy and mass in the deformed fish - These changes could cause fish to float and maneuver differently [4]  In future studies, combining microCT scanning results with motion capture will allow for new insights into the relationship between form and function. REFERENCES 1.Janssen, M. et al (2011). The Spine Journal, 11(4), 347-358.. 2.Tomasiewicz, H., et al (2014). Scoliosis, 9 (Suppl 1), O44. 3.Standen, E. M., & Lauder, G. V. (2005). Journal of Exp Biology, 208(14), 2753-63. 4.Eissa, A., et al. (2009). Chemosphere, 77(3), 419-425. CT Scan of both fish Image analysis and reconstruction Comparison of 3D structure