FIGURE 2.

Extracranial distribution of CSF time–activity curve correlated voxels. Sagittal (A) and axial (B) MR images from a representative NL show 3-dimensional extracranial shell region in blue and yellow (total nasal cavity). (C) Percentage distribution (±SEM) (n = 5 subjects) of shell and nasal cavity voxels whose tau PET derived time–activity curve are correlated with ventricular CSF time–activity curve, within range of r = 0.90–0.99. Data show 3-fold-greater percentage of CSF-correlated voxels in nasal cavity than in total shell. Shell voxels correlated at r > 0.95 were considered CSF-positive and are mapped in red in A and B.