SNRs and CNRs of the precontrast and postcontrast scan variants 3 and 7a
| Precontrast | P Value | Postcontrast | P Value | |||
|---|---|---|---|---|---|---|
| T1WI VIRTA (Variant 3)f | T1WI VIRTA (Variant 7) | T1WI VIRTA (Variant 3)f | T1WI VIRTA (Variant 7) | |||
| SNRtissueb | 28.0 ± 1.8 | 40.5 ± 3.4 | .005g | 27.9 ± 1.3 | 42.4 ± 2.8 | .005g |
| SNRcarotid vessel wallc | 15.3 ± 1.4 | 20.8 ± 2.7 | .005g | 17.2 ± 0.9 | 26.4 ± 4.0 | .005g |
| SNRbasilar vessel wall | 13.0 ± 1.4 | 15.9 ± 1.7 | .005g | 13.4 ± 2.4 | 19.2 ± 1.8 | .005g |
| SNRsuprasellar CSF | 9.1 ± 2.0 | 11.9 ± 2.2 | .007g | 11.3 ± 0.7 | 14.1 ± 2.4 | .013 |
| SNRpontine CSF | 5.9 ± 2.1 | 8.0 ± 2.0 | .007g | 6.5 ± 1.8 | 11.2 ± 2.6 | .007g |
| SNRblood | 3.6 ± 0.6 | 5.4 ± 1.2 | .005g | 3.8 ± 0.5 | 6.3 ± 1.4 | .007g |
| SNRpituitary gland | 23.0 ± 3.4 | 33.4 ± 4.7 | .005g | 33.3 ± 3.5 | 49.5 ± 6.7 | .005g |
| CNRcarotid vessel wall–CSFd | 6.1 ± 1.6 | 9.0 ± 1.5 | .005g | 6.0 ± 0.7 | 12.3 ± 3.6 | .007g |
| CNRbasilar vessel wall–CSFe | 7.2 ± 1.4 | 7.9 ± 1.4 | .059 | 7.0 ± 2.0 | 8.0 ± 1.9 | .285 |
| CNRcarotid vessel wall–bloodc | 11.6 ± 1.3 | 15.5 ± 2.9 | .013 | 13.5 ± 1.0 | 20.1 ± 3.8 | .007g |
↵a Data are mean and SD calculated in 10 subjects. A Wilcoxon signed rank test was used to compare the differences between precontrast variants 3 and 7 and postcontrast variants 3 and 7 (additional statistical comparisons are shown in On-line Table 2).
↵b Tissue ROI is located at the left orbital gyri.
↵c The mean of the left and right distal intracranial internal carotid arteries.
↵d Suprasellar CSF is used as reference.
↵e Pontine CSF is used as reference.
↵f Currently used in our clinic.
↵g Statistically significant (P < .008).