Diagnostic accuracy of diffusion tensor imaging in differentiating malignant from benign compressed vertebrae.

PURPOSE

To study diagnostic accuracy of diffusion tensor imaging (DTI) in differentiating malignant from benign compressed vertebrae.

METHODS

This study was done on 43 patients with compressed vertebrae on conventional magnetic resonance study that underwent DTI. The mean diffusivity (MD) and fractional anisotropy (FA) of malignant (n = 24) and benign (n = 19) compressed vertebrae were calculated by two readers.

RESULTS

There was a significantly lower (P = 0.001) MD of both readers between malignant (0.74 ± 0.2 and 0.78 ± 0.2 × 10 mm/s) and benign (1.67 + 0.3 and 1.63 ± 0.3 × 10 mm/s) compressed vertebrae. The FA of malignant compressed vertebrae of both readers (0.55 ± 0.2 and 0.52 ± 0.1) was significantly higher (P = 0.001) than that of benign (0.26 ± 0.1 and 0.28 ± 0.1) compressed vertebrae. There was excellent inter-reader agreement between both readers using MD (K = 0.91) and FA (K = 0.86). The thresholds of MD and FA used for differentiating malignant from benign compressed vertebrae of both readers were 1.15 and 1.16 × 10 mm/s and 0.37 and 0.34 with area under the curve (AUC) of 0.98, 0.96, 0.93, and 0.92 and diagnostic accuracy of 95.3%, 88.4%, 90.1%, and 86.0% respectively. Combined MD and FA revealed AUC of 0.99 and 0.97 and diagnostic accuracy of 95.3% and 93.0% by both readers respectively.

CONCLUSION

DTI is a non-invasive technique providing accurate imaging parameters that can be used for differentiating malignant from benign compressed vertebrae.