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BACKGROUND: Selection of the most appropriate sonographic scanning approaches for evaluation of hips can improve the method efficacy and decrease the scanning time. OBJECTIVE: To determine the sonographic scanning planes that best assess the proximal femoral vascularity in asymptomatic and pathologic hips of children with Legg-Calvé-Perthes disease (LCPD) and evaluate the frequency (number of hips with evidence of perfusion) and intensity (number of color pixels per region) of color pixels representing superficial cartilaginous and deep transphyseal vascularity in different anatomic regions of pathologic and asymptomatic hips using multipositional power Doppler approaches. MATERIALS AND METHODS: Seven scanning approaches (anterior-sagittal, anterior-transverse, coronal, adduction, perineal, 30 degrees and 70 degrees of abduction) were applied in 26 pathologic hips of 26 children with LCPD (age range 3-11 years) and in 25 contralateral asymptomatic hips. The color Doppler signals seen within the proximal femur were analyzed both qualitatively (overall/regional frequency) and quantitatively (intensity). RESULTS: The coronal (P=0.009) and 30 degrees abduction (P=0.047) approaches demonstrated a higher frequency of color pixels in pathologic than in asymptomatic hips. The anterior-sagittal, 30 degrees abduction, adduction and anterior-transverse planes performed best of all approaches (P=0.02) to assess deep transphyseal perfusion. The physis demonstrated a greater intensity of color signals representing intraosseous vascularity than other regions in pathologic hips (P=0.027), as noted with the anterior-sagittal approach. There was a tendency (P=0.06) towards a greater intensity of pixels representing cartilaginous vascularity in pathologic hips' physes with the coronal approach. CONCLUSION: Specific sonographic scanning planes are recommended for assessment of the proximal femoral vascularity of LCPD hips. The physis is the anatomic region that presents with the greatest intensity of color signals in pathologic hips.

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OBJECTIVE: In bone injury, repair results in local increased vascularity and bone marrow remodeling. Characterizing the vascular and metabolic imaging patterns of the proximal femur following an intertrochanteric osteotomy may help clinicians decide proper management of the patient. Our objective was to measure Doppler sonography and scintigraphy interval changes in the proximal femur following intertrochanteric osteotomy and compare imaging and histomorphometric measurements in the late post-operative stage (6 weeks after surgery) in a rabbit model of bone injury. MATERIALS AND METHODS: Both hips of 12 adult rabbits were imaged with power Doppler sonography and scintigraphy prior to and after (7 days and 6 weeks) unilateral osteotomy. Accuracy of the imaging methods was evaluated using hip operative status and histomorphometric results (vascular fractional area and number of vessels per area unit) as reference standard measures. RESULTS: A significant difference in the mean number of pixels was noted between operated and non-operated femura in late post-operative power Doppler examinations (P=0.049). Although without reaching statistical significance, the AUC of Doppler measurements (AUC=0.99) was numerically greater than the AUC of scintigraphy measurements (AUC=0.857+/-0.099) (P=0.15) in differentiating proximal femura with regard to their fractional vascular areas in the late post-operative stage. In contrast, scintigraphy tended to perform better (AUC=0.984+/-0.022) than Doppler ultrasound (AUC=0.746+/-0.131) to demonstrate the vascularity intensity per area unit (P=0.07) in the late stage. CONCLUSION: Our results warrant further investigation to determine the value of different imaging modalities for assessment of pathologic changes following hip surgery. Power Doppler sonography demonstrated larger AUCs (representing higher accuracy) for the discrimination of vascular fractional areas and scintigraphy, for discrimination of the number of vessels per area unit.

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OBJECTIVE: In bone injury, repair results in local increased vascularity and bone marrow remodeling. Characterizing the vascular and metabolic imaging patterns of the proximal femur following an intertrochanteric osteotomy may help clinicians decide proper management of the patient. Our objective was to measure Doppler sonography and scintigraphy interval changes in the proximal femur following intertrochanteric osteotomy and compare imaging and histomorphometric measurements in the late post-operative stage (6 weeks after surgery) in a rabbit model of bone injury. MATERIALS AND METHODS: Both hips of 12 adult rabbits were imaged with power Doppler sonography and scintigraphy prior to and after (7 days and 6 weeks) unilateral osteotomy. Accuracy of the imaging methods was evaluated using hip operative status and histomorphometric results (vascular fractional area and number of vessels per area unit) as reference standard measures. RESULTS: A significant difference in the mean number of pixels was noted between operated and non-operated femura in late post-operative power Doppler examinations (P=0.049). Although without reaching statistical significance, the AUC of Doppler measurements (AUC=0.99) was numerically greater than the AUC of scintigraphy measurements (AUC=0.857±0.099) (P=0.15) in differentiating proximal femura with regard to their fractional vascular areas in the late post-operative stage. In contrast, scintigraphy tended to perform better (AUC=0.984±0.022) than Doppler ultrasound (AUC=0.746±0.131) to demonstrate the vascularity intensity per area unit (P=0.07) in the late stage. CONCLUSION: Our results warrant further investigation to determine the value of different imaging modalities for assessment of pathologic changes following hip surgery. Power Doppler sonography demonstrated larger AUCs (representing higher accuracy) for the discrimination of vascular fractional areas and scintigraphy, for discrimination...

OBJETIVO: Regeneração em casos de lesão óssea resulta em aumento da vascularização local e remodelamento da medula óssea adjacente. A caracterização imagenológica de padrões vasculares e metabólicos no fêmur proximal após uma osteotomia intertrocantérica pode auxiliar ortopedistas a decidirem qual a terapêutica mais apropriada. O objetivo deste estudo foi avaliar as alterações temporais observadas por ultra-sonografia Doppler e cintilografia no fêmur proximal após a realização de uma osteotomia intertrocantérica; e comparar achados imagenológicos e histomorfométricos no estágio pós-operatório tardio (6 semanas após a cirurgia) num modelo animal de lesão óssea. MATERIAIS AND MÉTODOS: Ambos os quadris de 12 coelhos adultos foram examinados por ultra-sonografia power Doppler e cintilografia antes e após (7 dias e 6 semanas) uma osteotomia unilateral. A acurácia dos métodos de imagem foi avaliada usando-se o status operatório dos quadris and os resultados histomorfométricos (área vascular fracional e número de vasos/unidade de área) como medidas de referência. RESULTADOS: Uma diferença significativa foi observada entre o número médio de pixels presentes no fêmur proximal operado e não-operado ao exame de power Doppler obtido no estágio pós-operatório tardio (P=0.049). Embora ser atingir significância estatística, a área abaixo da curva ("area-under-the-curve") dos exames de power Doppler (AUC=0.99) for numericamente superior à área abaixo da curva dos exames de cintilografia (AUC= 0.857±0.099) (P=0.15) para diferenciar fêmures proximais com relação a suas áreas vasculares fracionais no estágio pós-operatório tardio. Ao contrário, a cintilografia tendeu a apresentar uma "performance" diagnóstica superior (AUC=0.984±0.022) em relação ao Doppler (AUC=0.746±0.131) para demonstrar a quantidade de vasos por unidade de área (P=0.07) no estágio tardio. CONCLUSÃO: Nossos resultados despertam a importância de continuar-se investigando...

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The authors evaluated the usefulness of an ultrasound contrast agent (SHU 508A) to help identify different scintigraphic phases of revascularization of the femoral head in children with Legg-Calvé-Perthes (LCP) disease. Eighteen unenhanced and contrast-enhanced power Doppler images and scintigrams of the pathologic hip in 18 children with LCP disease were compared. The scintigraphic stages of Conway's classification for LCP disease (stage A, recanalization; stage B, neovascularization) were compared with the degree of vascularity and mean peak enhancement ratios obtained from analysis of Doppler sonograms. Qualitatively, the patient's age (< or = or >7 years old) at the time of examination had a significant effect on the degree of vascularity visualized on postcontrast ultrasound images according to the scintigraphic stages. Quantitatively, there were no differences for overall mean peak enhancement ratios between stages A and B. Power Doppler ultrasound increased visualization of Doppler signals significantly but did not help in differentiating scintigraphic phases.

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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.

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