Jamil K, Walker T, Onikul E, Munns C F, Little D G
Discipline of Child and Adolescent Health, The Children's Hospital at Westmead Clinical School, University of Sydney, Sydney, NSW, Australia.
Orthopaedic Research and Biotechnology, The Children's Hospital at Westmead, Westmead NSW, Australia.
J Child Orthop. 2019 Feb 1;13(1):82-88. doi: 10.1302/1863-2548.13.180136.
Perthes' disease (PD) results from loss of blood supply to the hip and can progress to femoral head deformity. MRI in the early course of the disease can provide data on the initial extent of infarct. Vascularity of the femoral head is assessed by gadolinium-enhanced MRI (contrast MRI), which may be improved by the digital subtraction technique (subtraction MRI). We hypothesized that gadolinium-enhanced MRI without subtraction was comparable with subtraction MRI in depicting the femoral head perfusion.
In all, 34 patients (34 hips) with unilateral PD had gadolinium-enhanced MRI as part of a prospectively randomized study. Nine patients had three MRIs, 15 had two and ten had a single MRI. Measurement of perfusion of the femoral head (MRI perfusion index) was obtained using digital image analysis on all the MRIs, including both before and after subtraction. A paired sample t-test was performed to compare the measurements.
The mean age of the patients was 8.9 years (sd 1.6). At the time of diagnosis, the subtraction MRI did not elicit a statistically significant difference in MRI perfusion index measurements when compared with the contrast MRI (p = 0.19). The same findings were found when including all patients at various stages of the disease (p = 0.30). Qualitatively, although some subtraction MRI images showed superior delineation of epiphysis, there are no significant differences throughout the whole series.
Although the current literature supports the increasing role of the subtraction MRI for PD management, our study proposed that the contrast MRI without subtraction technique appears adequate in assessing femoral head perfusion.
Level I - Diagnostic study.
佩特兹病（PD）是由于髋关节血液供应丧失所致，可发展为股骨头畸形。疾病早期的MRI能够提供有关梗死初始范围的数据。股骨头的血管情况通过钆增强MRI（对比MRI）进行评估，数字减法技术（减法MRI）可能会改善评估效果。我们推测，未采用减法技术的钆增强MRI在描绘股骨头灌注方面与减法MRI相当。
总共34例单侧PD患者（34个髋关节）接受了钆增强MRI检查，这是一项前瞻性随机研究的一部分。9例患者进行了3次MRI检查，15例进行了2次，10例进行了1次MRI检查。使用数字图像分析对所有MRI图像（包括减法前后的图像）进行股骨头灌注测量（MRI灌注指数）。采用配对样本t检验比较测量结果。
患者的平均年龄为8.9岁（标准差1.6）。在诊断时，与对比MRI相比，减法MRI在MRI灌注指数测量中未显示出统计学上的显著差异（p = 0.19）。纳入疾病各个阶段的所有患者时也得到了相同的结果（p = 0.30）。定性地说，虽然一些减法MRI图像显示骨骺的描绘更清晰，但在整个系列中没有显著差异。
尽管目前的文献支持减法MRI在PD治疗中发挥越来越重要的作用，但我们的研究表明，未采用减法技术的对比MRI似乎足以评估股骨头灌注。
I级——诊断性研究。
