de Bazelaire C, Pluvinage A, Chapelier M, Hamy A S, Albiter M, Farges C, Bourrier P, Zagdanski A M, Espié M, de Kerviler E, Frija J
Service de radiologie, Hôpital Saint-Louis, 1 avenue Claude Vellefaux, 75475 Paris cedex 10, France.
J Radiol. 2010 Mar;91(3 Pt 2):394-404; quiz 405-7. doi: 10.1016/s0221-0363(10)70055-x.
Diffusion-weighted imaging is helpful to further characterize lesions that remain indeterminate after morphological and dynamic MR evaluation. Suspicious lesions are hyperintense on diffusion-weighted images with corresponding low ADC values, indicating restricted diffusion and hypercellularity. Benign lesions and tumors responding to treatment usually have no diffusion restriction. ADC maps are useful for T2W hyperintense lesions that could mask the presence of restricted diffusion. Image fusion is sometimes needed to accurately localize enhancing lesions on ADC maps. For indeterminate lesions, a hypocellular appearance suggests a lower ACR category whereas the presence of restricted diffusion suggests a higher category.
扩散加权成像有助于进一步明确在形态学和动态磁共振评估后仍不确定的病变特征。可疑病变在扩散加权图像上呈高信号，相应的表观扩散系数（ADC）值较低，提示扩散受限和细胞增多。良性病变及对治疗有反应的肿瘤通常无扩散受限。ADC图对可能掩盖扩散受限的T2加权高信号病变很有用。有时需要图像融合以在ADC图上准确定位强化病变。对于不确定的病变，细胞减少的表现提示ACR分类较低，而扩散受限提示分类较高。
