Monostototic & polystotic marrow disorders:MRI characterization versus biopsy

Abstract

MRI is superior to other imaging modalities in evaluating bone marrow because it is remarkably sensitive in detecting lipid; therefore, MRI can be used to detect processes that alter the relative amounts of fat and water in bone marrow. In order to interpret the appearances of marrow seen on MRI and to distinguish normal from abnormal, it is important to understand the normal components and composition of bone marrow, which vary greatly with age and anatomic location within the skeleton. The bone marrow can be affected by infectious, inflammatory, metabolic, and neoplastic processes. Its appearance can be affected as well by underlying degenerative changes, trauma, and numerous iatrogenic therapies, including vertebroplasty, radiation or chemo-therapy, and medications designed to stimulate the bone marrow. Various MR imaging techniques are available to accentuate the different chemical and cellular compositions of normal marrow and marrow diseases. The objectives of this study are to evaluate the relative conspicuousness of bone marrow lesions on images obtained by using two of the most widely available fat-suppression techniques, short-TI inversion recovery (STIR) and fat-saturation T2-weighted imaging, and to analyze the effect of these methods on image quality. In addition, we thought to determine if either or both of these sequences provide significant advantages relative to conventional T1 weighted spin-echo images for the evaluation of bone marrow lesions. Then we further analyzed the MRI sensitivity & possible specificity in certain groups; Metastatic, lymphoma, myeloma & differentiation of benign and malignant vertebral collapse. The reasons of our specific interest in these topics were not just because of its importance as a part of our daily clinical practice but also since they pose most of the clinical dilemma, we needed to find a way to answer the questions of our referring physician’s since the treatment plans may dramatically change based on the imaging findings. In this study, T1-weighted, fat saturation T2-weighted, and STIR sequences all provided a variable degree of sensitivity for detection of most types of bone marrow abnormalities. Quantitative measurements indicate that the conspicuousness of lesions is maximal on STIR images followed by