Distributional characteristics and regional variation of hounsfield units value across whole spinal vertebral bodies: a cross-sectional study based on 200 objects and 6600 vertebras measurement

Purpose: To describe and analyze the distribution characteristics of hounsfield units (HU) value from computerized tomography (CT) scan across whole spine. Methods: Consecutive adult subjects undergoing cervical, thoracic, lumbar spine CT and DEXA scanning between January 2020 and June 2024 were screened in the study. The CT-HU value of vertebras was respectively measured from C2-L5.The distribution characteristics and reginal heterogeneity of HU value were analyzed. The correlation between HU value of C2-L5 and T-score of lumbar vertebras were also evaluated. Results: There were 200 subjects with 6600 vertebras enrolled in the study with the mean age of 63.7±12.6 years including 92 male and 108 female. There were no significant differences of CT-HU value between axial, sagittal and coronal planes for the same vertebra. HU value showed a downward trend from cervical to thoracic and lumbar spine. HU value of all vertebras in osteoporosis group was significantly lower than normal and osteopenia groups. HU value of all vertebras was significant higher in male than female and the mean HU values gradually decreased with age. L3 T-score has the highest correlation with HU value of C2-L5 vertebra and the HU value of thoracic vertebras has the highest correlation with L3 T-score, followed by cervical and lumbar vertebras. Conclusion: The CT-HU value has distinct distribution characteristics for different part of spine and the reginal variation from C2 to L5 share certain trends and rules. Despite of significant variation, vertebral CT-HU value has intrinsic correlation with bone mineral density for individuals.