BACKGROUND CONTEXT Evaluation of living tissue elasticity has wide applications in disease characterization and prognosis prediction. Few previous ex vivo attempts have been made to characterize spinal cord elasticity (SCE). Recently, tissue elasticity assessment has been clinically feasible using ultrasound shear wave elastography (SWE). PURPOSE The current study aims to characterize SCE in healthy dogs,in vivo, utilizing SWE, and address SCE changes during compression. METHODS TenGreyhound dogs (mean age, 14 months; mean weight, 14.3kg) were anesthetized andtracheallyintubated, with hemodynamic and neurologic monitoring. Three-level, mid-cervical laminectomy was performed. SCE was assessed at baseline. Next, 8 and 13mm-balloon compressions were sequentially appliedventralto the spinal cord. RESULTS The mean SCE was 18.5±7kPa.Elasticityof the central canal, pia mater, and dura mater were 21.7±9.6kPa, 26.1±14.8kPa, and 63.2±11.5kPa, respectively. As expected, the spinal cord demonstrated less elasticity than dura mater (p CONCLUSIONS InvivoSCEevaluation using SWE is feasible and comparable to earlier reports, as demonstrated by physical sectioning ofspinalcord. The compressed spinal cord is stiffer than a free spinal cord, witha linear increase in SCE with increasing mechanical compression. Knowledge of the biomechanical properties of the spinal cord including SCE has potential implications for disease management and prognosis. To our knowledge, this study is the first to confirm the feasibility of this technique for spinal cord evaluation. It, thus, supports future work to address technical issues and challenges associated with USE in the spinal cord, in addition to determining USE values that specify spinal cord biomechanical properties.