TSPO and Huntington disease: The core subject of this review is the targeting of 18-kDa translocator protein (TSPO) for: (1) Diagnostic approaches, in particularspecific positron emission tomography (PET)scan) to visualize brain damage due to disease and injury; and (2) therapeutic approaches, i.e., application of TSPO ligands with different structures and properties to animal models for Parkinson disease (PD), Huntington disease, traumatic brain injury (TBI), and stroke.