Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics.

OBJECTIVE

To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO).

MATERIALS AND METHODS

Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Slope) and CT variables were the bone and segment involved (OO and OO respectively), OO location relative to the native cortex (OO), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmax). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed.

RESULTS

DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Slope of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmax of 1.10 ± 0.60 mm. By univariate analysis, Slope correlated significantly with pain duration and Dmax (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Slope correlated significantly with OO (P < 0.001), with a steeper slope for OOs located in short or flat bones.

CONCLUSION

This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones.