Table 2.
Comparison of differences in SUVR ([18F]RO948 vs [18F]flortaucipir) pre and post partial volume correction and using different reference regions
| Non-PVC mean (% difference§) | PVC mean (% difference§) | Inferior CBL mean (% difference§) | Whole CBL mean (% difference§) | Eroded WhM mean (% difference§) | |
|---|---|---|---|---|---|
| Stage I/II | 7.85 | 6.96 | 6.96 | 9.33 | 5.93 |
| Stage III/IV | − 0.28 | − 1.06 | − 0.28 | 2.08 | − 1.35 |
| Stage V/VI | − 3.58 | − 4.24 | − 3.58 | − 1.22 | − 4.69 |
| Stage I–IV | 0.14 | − 0.50 | 0.14 | 2.50 | − 0.92 |
| Inferior temporal ctx | 0.76 | 0.32 | 0.76 | 3.12 | − 0.31 |
| Hippocampus | − 19.83 | − 15.09 | − 15.09 | − 12.75 | − 16.24 |
Stage I/II corresponds to entorhinal cortex, stage III/IV temporal/limbic cortex, stage V/VI neocortex, and I–IV corresponds to a temporal meta-ROI.
CBL, cerebellum; ctx, cortex; PVC, partial volume error correction; WhM, white matter
§Formula used to calculate differences (mean in percent) between regional tracer retention: 100 × ([18F]RO948 SUVR – [18F]flortaucipir SUVR)/(([18F]RO948 SUVR + [18F]flortaucipir SUVR)/2