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4RTNI-2 (4 Repeat Tauopathy Neuroimaging Initiative – Cycle 2) is a consortium of academic medical centers in partnership with patient support organizations dedicated to conducting clinical research in corticobasal degeneration (CBD), progressive supranuclear palsy (PSP), and suggestive of or variant PSP (so/vPSP) syndromes.

The goals of this study are to identify the most reliable methods for tracking CBD, PSP and so/vPSP over time, to provide information about the relative value of novel imaging techniques for diagnosis, and to evaluate the value of imaging techniques versus biomarkers in patient samples.

Study Participants

Subjects are between 40 and 80 years old with no known neurological disease or who have corticobasal syndrome or degeneration (CBS or CBD), progressive supranuclear palsy (PSP), or suggestive of- or variant- syndromes of progressive supranuclear palsy (so/vPSP by 2017 MDS PSP Criteria). A reliable study partner is also asked to participate.

Clinical evaluations include neurological and physical examinations, interviews with the study partner, MRI scans of the brain, amyloid and tau sensitive PET scans of the brain, eye movement testing, retinal imaging, memory & thinking testing, daily-function assessments, computer-based tests of decision-making and executive abilities, collection of a detailed family history, blood and cerebrospinal fluid (CSF) collection for analysis and storage/banking, behavioral testing, speech and language evaluations, and mood questionnaires. PSP and CBD participants are seen 3 times in one year at 6-month intervals; so/vPSP and healthy participants are seen 4 times in two years.

Available Data

The comprehensive database for 4RTNI-2 includes item-level data from medical, functional, and neuropsychological evaluations, as well as diagnostic information. Datasets may be requested through 4RTNI-2; use must conform to the 4RTNI-2 Access and Publication Policy. Structural MRI data is available for a subset of participants and may be downloaded through the Laboratory for NeuroImaging at USC. A fixed minimal dataset is available through the NCRAD catalog.

Available Biospecimens

Genomic DNA, RNA, Plasma, Serum, PBMCs, CSF