Table 3.
Protocol Parameters and Reproducibility of Quantitative Measurements on 3 T MR: Comparison with previous 1.5 T MR studies
| 3.0-T |
1.5 T [20,22,30] |
Difference | |
| Interpolated Pixel Size [mm2] | 0.25 mm × 0.25 mm = 0.0625 mm2 | 0.3 mm × 0.3 mm = 0.09 mm2 | -31% |
| Scan Range [mm] | 30 | 24 | + 25% |
| Total Scan Time [minutes] | 13:05 Protocol CM- 22:43 Protocol CM+ |
19:30 CM- 31:30 CM+ |
-33% -28% |
| Scan Time per Slice [seconds] | |||
| T1w | 18.5 | 35.0 | -47% |
| PD/T2w | 6.1 | 15.0 | -59% |
| TOF | 4.8 | 9.6 | -50% |
| Non-Diagnostic Exams [%] | 1/38 [2.6%] | 27/252 [10.7%] | |
| PAT factor | 2 DCE = 4 |
1 | +100% |
| Coefficient of Variation | |||
| a.) Lumen Area | 1.5% | 4.3% | |
| b.) Wall Area | 4.5% | 5.8% | |
| c.) Total Vessel Area | 1.9% | 3.3% | |
| d.) NWI | 3.0% | n.a. | |
| ICC (95% CI) | |||
| a.) Lumen Area | 1.00 (0.99-1.00) | 0.99 (0.98-1.00) | |
| b.) Wall Area | 0.98 (0.93-1.00) | 0.97 (0.95-0.99) | |
| c.) Total Vessel Area | 1.00 (0.99-1.00) | 0.98 (0.97-1.00) | |
| d.) NWI | 0.88 (0.60-0.97) | n.a. | |
Protocol CM- = no contrast media used, time for TOF, PDw, T2w and T1w images; CM+ = same as CM-, + contrast-enhanced T1w and dynamic contrast enhanced sequences added; PAT = Parallel Acquisition Technique; DCE = Dynamic Contrast Enhanced Sequences; ICC = Intra Class Correlation Coefficient; NWI = Normalized Wall Index; CI = Confidence Interval