Relationships with anterior-posterior diameter by the Pearson correlation coefficient (95% confidence intervals)
| Foramen of Magendie | Lower End of Cerebral Aqueduct | Upper End of Cerebral Aqueduct | Midbrain | |
|---|---|---|---|---|
| Dorsal region of the cerebral aqueduct | ||||
| OSS amplitude | 0.55 (0.36–0.69) | 0.47 (0.26–0.63) | 0.28 (0.05–0.48) | NS |
| Maximum OSS | 0.53 (0.34–0.68) | 0.41 (0.20–0.59) | NS | NS |
| Minimum OSS | –0.51 (–0.66 to –0.31) | –0.46 (–0.63 to –0.26) | –0.32 (–0.51 to –0.10) | NS |
| TAWSS | 0.56 (0.37–0.70) | 0.40 (0.18–0.58) | NS | NS |
| OSI | NS | NS | NS | NS |
| Ventral region of the cerebral aqueduct | ||||
| OSS amplitude | NS | 0.27 (0.04–0.47) | NS | NS |
| Maximum OSS | NS | 0.31 (0.08–0.50) | NS | NS |
| Minimum OSS | NS | NS | NS | NS |
| TAWSS | 0.26 (0.04–0.47) | 0.33 (0.10–0.52) | NS | NS |
| OSI | NS | NS | NS | NS |
Note:—NS indicates not significant (P ≥ .05) by the Pearson correlation analysis.