Table 3.
Averaged global cerebral blood flow assessed by 15O-H2O PET and phase-contrast mapping MRI.
| Resting (n = 26/14) | Hyperventilation (n = 17/9) | Post-acetazolamide (n = 19/10) | |
|---|---|---|---|
| PCM MRI (mL/100 g/min) | 58.5 ± 10.7b (0.18) | 33.0 ± 8.6a,b (0.26) | 89.6 ± 27.1a,b (0.30) |
| Change vs. rest (mL/100 g/min) | – | −26.9 ± 9.5 | 31.3 ± 17.9 |
| Change vs. rest (%) | – | −36.9 ± 19.6 | 52.4 ± 23.8 |
| 15O-H2O PET (mL/100 g/min) | 38.6 ± 5.7b (0.15) | 24.7 ± 5.8a,b (0.23) | 57.3 ± 9.6a,b (0.17) |
| Change vs. rest (mL/100 g/min) | – | −16.4 ± 10.5 | 19.4 ± 8.3 |
| Change vs. rest (%) | – | −35.0 ± 10.2 | 52.5 ± 22.6 |
Note: All values are the average ± standard deviation of the two measurements in each condition, coefficient of variation in parenthesis. For each state, n indicates the number of observations /number of subjects. The change is calculated as the difference of the average gCBF in resting state and in hyperventilation or after acetazolamide. Only subjects with measurements in at least two states contribute the calculation of gCBF changes.
p < 0.05 for differences with resting state, within technique.
p < 0.05 for differences between techniques, within state.
PCM MRI: phase contrast mapping magnetic resonance imaging; PET: positron emission tomography; gCBF: global cerebral blood flow.