Utility of opportunistic CT Hounsfield Units determined bone quality in chilean women.

OBJECTIVE

To describe the correlation between Hounsfield Units in opportunistic computed tomography (CT scan) and T-score measured by dual energy X-ray absorptiometry (DXA) in the Chilean population.

METHOD: Female patients over 50 years old with CT scan and DXA performed within 6 months. Hounsfield units (HU) were measured by circular regions-of-interest placed on axial slice image of the L1 vertebral body in the CT scan. T-score was obtained through DXA scan in L1-L4 vertebrae.

RESULTS

144 female patients were included with a mean age in years of 68.39 ± 8.75. A moderate correlation was found between T-score and HU (Pearson coefficient of 0.6, p < 0.001). The mean values of HU differ significantly between the groups of Osteoporosis (OP) (89.46 ± 20.20), Osteopenia (110.87 ± 30.74) and normal bone mineral density (154.53 ± 38.90) (p < 0.01). The area under curve for diagnostic capacity was 0.81 (95% CI 0.72-0.9). The HU thresholds for the diagnosis of OP were 101 (sensitivity 75%, specificity 75%).

CONCLUSION

Opportunistic CT scan is a useful tool in Chilean population to perform a screening for OP.