Balliu E, Vilanova J C, Peláez I, Puig J, Remollo S, Barceló C, Barceló J, Pedraza S
Department of Magnetic Resonance, IDI Girona, Hospital Universitari de Girona Dr Josep Trueta, Girona, Spain.
Eur J Radiol. 2009 Mar;69(3):560-6. doi: 10.1016/j.ejrad.2007.11.037. Epub 2008 Feb 13.
The aim of this study is to evaluate the value of the apparent diffusion coefficient (ADC) obtained in diffusion-weighted (DW) MR sequences for the differentiation between malignant and benign bone marrow lesions.
Forty-five patients with altered signal intensity vertebral bodies on conventional MR sequences were included. The cause of altered signal intensity was benign osteoporotic collapse in 16, acute neoplastic infiltration in 15, and infectious processes in 14; based on plain-film, CT, bone scintigraphy, conventional MR studies, biopsy or follow-up. All patients underwent isotropic DW MR images (multi-shot EPI, b values of 0 and 500 s/mm(2)). Signal intensity at DW MR images was evaluated and ADC values were calculated and compared between malignancy, benign edema and infectious spondylitis.
Acute malignant fractures were hyperintense compared to normal vertebral bodies on the diffusion-weighted sequence, except in one patient with sclerotic metastases. Mean ADC value from benign edema (1.9+/-0.39 x 10(-3) mm(2)/s) was significantly (p<0.0001) higher than untreated metastasic lesions (0.9+/-1.3 x 10(-3)mm (2)/s). Mean ADC value of infectious spondilytis (0.96+/-0.49 x 10(-3) mm(2)/s) was not statistically (p>0.05) different from untreated metastasic lesions. ADC value was low (0.75 x 10(-3) mm(2)/s) in one case of subacute benign fracture.
ADC values are a useful complementary tool to characterize bone marrow lesions, in order to distinguish acute benign fractures from malignant or infectious bone lesions. However, ADC values are not valuable in order to differentiate malignancy from infection.
本研究旨在评估扩散加权磁共振成像（DW-MR）序列中获得的表观扩散系数（ADC）值在鉴别恶性与良性骨髓病变中的价值。
纳入45例常规磁共振序列上椎体信号强度改变的患者。信号强度改变的原因包括16例良性骨质疏松性椎体压缩骨折、15例急性肿瘤浸润以及14例感染性病变；诊断依据为X线平片、CT、骨闪烁显像、常规磁共振检查、活检或随访。所有患者均接受各向同性DW-MR成像（多次激发回波平面成像，b值为0和500 s/mm²）。评估DW-MR图像上的信号强度，计算ADC值，并在恶性病变、良性水肿和感染性脊柱炎之间进行比较。
在扩散加权序列上，除1例硬化性转移瘤患者外，急性恶性骨折的椎体信号高于正常椎体。良性水肿的平均ADC值（1.9±0.39×10⁻³ mm²/s）显著高于未治疗的转移瘤病变（0.9±1.3×10⁻³ mm²/s，p<0.0001）。感染性脊柱炎的平均ADC值（0.96±0.49×10⁻³ mm²/s）与未治疗的转移瘤病变相比，差异无统计学意义（p>0.05）。1例亚急性良性骨折患者的ADC值较低（0.75×10⁻³ mm²/s）。
ADC值是一种有助于鉴别骨髓病变的有用补充工具，可用于区分急性良性骨折与恶性或感染性骨病变。然而，ADC值对于鉴别恶性病变与感染性病变并无价值。
