The Role of DaT-SPECT Imaging in the Evaluation of Progressive Supranuclear Palsy

Introduction: Progressive supranuclear palsy (PSP) is an atypical Parkinsonian disorder characterized by a range of clinical phenotypes, reflecting its multiple subtypes. As a result, accurate diagnosis during life remains challenging, underscoring the need for reliable biomarkers. The present narrative review aims to evaluate whether dopamine transporter single-photon emission computed tomography (DaT-SPECT) can serve as a biomarker in the assessment of PSP. Methods: The database search identified 31 original research articles relevant to our study objective. Of these, 17 studies included PSP patients and utilized DaT-SPECT as the sole molecular imaging modality; 9 studies combined DaT-SPECT with at least one additional molecular imaging technique; and 5 studies integrated DaT-SPECT with a laboratory-based biomarker of neurodegenerative disease. Results: DaT-SPECT appears to demonstrate low specificity and variable sensitivity for PSP across studies. Discussion: Combining DaT-SPECT with other diagnostic biomarkers, especially brain magnetic resonance imaging and other nuclear imaging modalities, may improve diagnostic accuracy, especially given its relatively low specificity for PSP. Nevertheless, these initially promising findings need to be validated in large, multicenter studies that include and clearly define multiple, autopsy-confirmed PSP subtypes.