Median Cortical Thickness (Ct.Th) at the Thoracic (T) and Lumbar (L) vertebrae (whiskers 5–95%) as a function of time (months) following the baseline whole body CT scan in NHPs removed prior to the study conclusion after the 2 month follow-up (Top) and in NHPs enrolled to the study conclusion (Bottom). Chest only irradiation occurred at 2 month after the baseline imaging was performed and this was set to time point t =0. Paired T test compared Ct. Th for NHPs that were removed prior to study conclusion, while repeated measures ANOVA with Bonferroni post hoc analyses were used for those NHPs that lived to the study conclusion. Bars and associated p values identify significant differences between individual groups; main ANOVA p value presented above graph. The interassay coefficient of variation for each CT-based measure of Ct.Th for those that remained until study conclusion were 10.6–15.0% for T9, 11.1–12.9% for L2, and 9.2–12.4% for L4; and for those that were removed prior to the study conclusion were 10.6–15.2% for T9, 13.1–16.3% for L2, and 16.7–20.0% for L4.