Magnetic Resonance Imaging in the Neuroimaging of Progressive Supranuclear Palsy—Parkinsonism Predominant: Limitations and Strengths in Clinical Evaluation

Progressive Supranuclear Palsy (PSP) is an atypical Parkinsonism, pathologically described as a four-repeat tauopathy. The contemporary criteria for diagnosis of PSP indicate akinesia, oculomotor dysfunction, postural instability, and language/cognitive impairment as core symptoms. Among these features, the first two are linked to PSP-Parkinsonism predominant (PSP-P). PSP-P is the second most common subtype of PSP, following PSP-Richardson's syndrome (PSP-RS), and is associated with a more gradual deterioration, beneficial course, and longer life expectancy after diagnosis. It is also problematic in terms of clinical evaluation, as this entity may overlap with Parkinson's disease (PD) in early stages and with other atypical Parkinsonisms in more advanced stages. The evolution in understanding PSP and the possible progress in care and therapy of the disease leads to the necessity of finding optimal examination methods with sufficient sensitivity and specificity. In this context, PSP-P seems a crucial point. The goal of this narrative review is to provide an overview of the possibilities provided by Magnetic Resonance Imaging (MRI) assessments in terms of PSP-P and analyze their strengths and weaknesses.