The Potential of Metabolic Imaging

Metabolic imaging is a field of molecular imaging that focuses and targets changes in metabolic pathways for the evaluation of different clinical conditions. Targeting and quantifying metabolic changes non-invasively is a powerful approach to facilitate diagnosis and evaluate therapeutic response. This review addresses only techniques targeting metabolic pathways. Other molecular imaging strategies, such as affinity/receptor imaging or microenvironment-dependent methods are beyond the scope of this review. Here we describe the current state of the art in clinically translatable metabolic imaging modalities. Specifically, we will focus on positron emission tomography (PET) and magnetic resonance spectroscopy (MRS), including conventional 1H and 13C MRS at thermal equilibrium and hyperpolarized magnetic resonance imaging (HP MRI). In this paper, we first provide an overview of metabolic pathways that are altered in many pathological conditions and the corresponding probes and techniques used to study those alterations. We will then describe the application of metabolic imaging to several common diseases including cancer, neurodegeneration, cardiac ischemia, and infection/inflammation.