Multiparametric imaging: Cutting-edge sequences and techniques including diffusion-weighted imaging, magnetic resonance spectroscopy, and PET/CT or PET/MRI [Chapter 15.]

Magnetic resonance imaging (MRI) of the breast is an indispensible tool in breast imaging, with several indications. Dynamic contrast-enhanced MRI (DCEMRI) provides mainly morphological, and, to some extent, functional information about perfusion and vascularity, resulting in excellent sensitivity and good specificity for breast cancer diagnosis. Multiparametric imaging of the breast aims to quantify and visualize biological, physiological, and pathological processes at the cellular and molecular levels. Multiparametric imaging of the breast can be performed at different field-strengths (l. 5—7T) and comprises established and emerging MRI parameters, such as diffusion-weighted imaging (DWI), MR spectroscopy (MRS), sodium imaging (23NaMRI), chemical exchangesaturation transfer (CEST) imaging, blood oxygen level—dependent (BOLD) MRI, nuclear imaging, such as positron emission tomography (PET) with different radiotracers, and combinations of techniques (e.g., PET/CT and PETIMRI). Several functional parameters with MRI and PET have also been assessed for imaging of bremsttumors, and their combined application is defined as multiparametric imaging. Available data suggest that multiparametric imaging using different functional MRI and PET parameters can provide detailed information about the hallmarks of cancer and may provide additional specificity. This chapter aims to provide a comprehensive overview Of the current possibilities and emerging techniques in multiparametric imaging of the breast with cuttingedge sequences and techniques.