Contrast-enhanced power Doppler sonography: assessment of revascularization flow in Legg-Calvé-Perthes' disease.

A total of 26 children (26 affected, 25 control hips) with Legg-Calvé-Perthes' disease (LCP) met the cooperation requirements for inclusion in the study using contrast-enhanced power Doppler sonography for assessment of changes in the revascularization flow. Sagittal sonograms were obtained before and at the peak effect of an intravenously injected microbubble-based contrast agent. Overall mean peak enhancement ratios were greater for children with later onset of disease (>5.8 years old) than for those with earlier onset (< or = 5.8) (p = 0.02). The use of ultrasound (US) contrast agents improved depiction of proximal femoral vascularity in all regions of the femoral head: epiphysis (n = 3, pre; n = 8, postcontrast), physis (n = 12, pre; n = 21, postcontrast) and metaphysis (n = 6, pre; n = 8, postcontrast) and resulted in a marked increase in the number of mean pixel intensity values within the physis (p = 0.02). In conclusion, contrast-enhanced power Doppler sonography is an effective method for demonstration of changes from the revascularization process in LCP, particularly within the physis.