Diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) values for detection of malignant vertebral bone marrow lesions

Malignant spinal bone marrow disorders are one of the major causes of significant morbidity and reduction in quality of life in oncological patients. Thus, the characterization of these conditions is of crucial importance in the management of these patients. Magnetic resonance (MR) imaging plays a vital role in differentiation between benign and malignant spinal bone marrow disorders. However, morphological imaging features, based on T1 and T2 relaxation properties, might fail in differentiating between these conditions because signal characteristics may overlap. Quantitative MR imaging based on diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) values has been proved to help in defining the nature of the lesion. The aims of this paper were: to review basic principles of DWI technique and ADC maps, to describe DWI and ADC maps appearances of normal vertebral bone marrow briefly, to discuss the DWI and ADC maps characteristics in vertebral malignant lesions, to provide indications for differential diagnosis between malignant and benign lesions.