Advances in Bone Marrow Imaging: Strengths and Limitations from a Clinical Perspective

Abstract

Conventional magnetic resonance imaging (MRI) remains the modality of choice to image bone marrow. However, the last few decades have witnessed the emergence and development of novel MRI techniques, such as chemical shift imaging, diffusion-weighted imaging, dynamic contrast-enhanced MRI, and whole-body MRI, as well as spectral computed tomography and nuclear medicine techniques. We summarize the technical bases behind these methods, in relation to the common physiologic and pathologic processes involving the bone marrow. We present the strengths and limitations of these imaging methods and consider their added value compared with conventional imaging in assessing non-neoplastic disorders like septic, rheumatologic, traumatic, and metabolic conditions. The potential usefulness of these methods to differentiate between benign and malignant bone marrow lesions is discussed. Finally, we consider the limitations hampering a more widespread use of these techniques in clinical practice.

Advanced Imaging of Gout and Other Inflammatory Diseases Around the Knee

“…In the last few decades, novel MRI techniques have emerged: a robust fat suppression (FS) technique using chemical shift imaging (CSI), diffusion-weighted imaging (DWI), advanced quantitative MRI techniques, such as T2 mapping and T1ρ mapping, dynamic contrast-enhanced MRI (DCE-MRI), diffusion tensor imaging, and whole-body MRI (WB-MRI). [4][5][6] Robust FS techniques predominantly involve Dixon sequences that use CSI. They take advantage of the slight difference in resonance frequency between water and fat protons to provide a series of four sets of images: in-phase (IP), out-of-phase (OP), water only, and fat only.…”

“…They take advantage of the slight difference in resonance frequency between water and fat protons to provide a series of four sets of images: in-phase (IP), out-of-phase (OP), water only, and fat only. 4 Although Dixon described it in the 1980s, it has only recently become possible to associate this method with spin-echo (SE)-based sequences, the backbone of MSK MRI protocols, opening the door for multiple applications in this field. CSI MRI can also be used to probe bone marrow fat content quantitatively, by measuring the signal drop between IP and OP images or by calculating the fat fraction.…”

“…4 The Dixon method has proven to be more robust to magnetic field inhomogeneities than chemical shift selective suppression while providing a better signal-to-noise ratio than short tau inversion recovery sequences. 4 Therefore, it is an appealing technique for large field-of-view (FOV) imaging of the bone marrow, whereas in knee assessment its use is generally reserved to assess tumors rather than inflammatory conditions. The robust FS and reduced examination time are additional advantages of Dixon acquisitions.…”

“…Spectral CT operates on the principle that tissue attenuation is influenced not just by density but also by the atomic number (Z) and the photon beam's energy. 4 By leveraging these properties, spectral CT can characterize and quantify specific tissue components. 4 The most prevalent subset of spectral CT is DECT, using two distinct X-ray energy spectra.…”

“…4 By leveraging these properties, spectral CT can characterize and quantify specific tissue components. 4 The most prevalent subset of spectral CT is DECT, using two distinct X-ray energy spectra. 4 In dual-source DECT, two tube-detector pairs are utilized, with adjustable tube voltages, facilitating fast single energy combinations.…”