CSF velocity parameters
| Aqueductal Flow | ||
|---|---|---|
| Unrestricted Flow | Jugular Compression | |
| Maximum caudal velocity (cm/s) | ||
| Mean | 1.18 ± 0.33 | 1.53 ± 0.42 |
| Range | 0.81–1.85 | 1.04–2.36 |
| t test | t = −4.96, P = .0004a | |
| Maximum cranial velocity (cm/s) | ||
| Mean | 1.38 ± 0.57 | 1.62 ± 0.62 |
| Range | 0.73–2.47 | 0.66–2.48 |
| t test | t = 1.58, P = .066 | |
| Duration of caudally directed flow (% cardiac cycle) | ||
| Mean | 49.9 ± 5.2% | 51.4 ± 5.3% |
| Range | 40.7%–57.7% | 42.1%–61.7% |
| t test | t = −1.0, P = .160 | |
↵a P < .05, paired t test.