Table 3.
Comparison of pre-operative cerebral and tumoral blood flow metrics between glioma grades
| Grade 2 | Grade 3 | Grade 4 | ANOVA | Bonferroni | Factorial ANOVA | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M ± SD | R | N | M ± SD | R | N | M ± SD | R | N | |||||
| CBF | Max CBF overall | 85.3 (±0.0) | 1, 13 | 80.0 (±0.0) | 1, 17 | 49.6 (±20.0) | 35.2–77.0 | 2, 81 |
F = 39.7 p < 0.001 |
two vs 3 (p > 0.99) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
|||
| Perilesional flow | Max perilesional relative flow - white matter reference | 1.1 (±0.0) | 2, 28 | 1.3 (±0.0) | 1, 14 | 1.7 (±0.4) | 1.1–2.0 | 2, 71 |
F = 39.8 p < 0.001 |
two vs 3 (p = 0.215) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
|||
| TBF | Mean TBF | 34.2 (±20.2) | 4.2–51.7 | 6, 113 | 64.4 (±10.5) | 49.0–71.3 | 2, 26 | 98.0 (±34.5) | 49.0–136.5 | 7, 154 |
F = 167.1 p < 0.001 |
two vs 3 (p < 0.001) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
Contrast: two vs 3: N/A two vs 4: MD = 53.8, p < 0.001 three vs 4: N/A Non-contrast based two vs 3: MD = 23.8, p < 0.001 two vs 4: MD = 76.5, p < 0.001 three vs 4: MD = 52.7, p < 0.001 |
| Max TBF | 70.8 (±13.8) | 46.9–85.8 | 4, 46 | 122.9 (±34.9) | 73.0–146.4 | 2, 25 | 145.5 (±48.0) | 74.5–250.0 | 6, 214 |
F = 56.9 p < 0.001 |
two vs 3 (p < 0.001) two vs 4 (p < 0.001) three vs 4 (p = 0.042) |
||
| Mean rTBF - all reference ROIs | 1.5 (±0.6) | 0.9–1.7 | 7, 99 | 2.8 (±0.9) | 1.4–3.7 | 5, 49 | 3.8 (±2.1) | 1.6–7.9 | 6, 188 |
F = 63.9 p < 0.001 |
two vs 3 (p < 0.001) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
Contrast based two vs 3: MD = 0.98, p = 0.03 two vs 4: MD = 1.50, p < 0.001 three vs 4: MD = 0.52, p = 0.40 Non-contrast based two vs 3: MD = 1.58, p < 0.001 two vs 4: MD = 3.40, p < 0.001 three vs 4: MD = 1.82, p < 0.001 |
|
| Mean rTBF - white matter reference | 1.8 (±0.5) | 1.3–2.7 | 4, 66 | 3.0 (±0.7) | 1.9–3.7 | 4, 41 | 4.0 (±2.1) | 2.1–8.0 | 5, 177 |
F = 40.2 p < 0.001 |
two vs 3 (p = 0.001) two vs 4 (p < 0.001) three vs 4 (p = 0.007) |
Contrast based two vs 3: MD = 0.98, p = 0.04 two vs 4: MD = 1.50, p < 0.001 three vs 4: MD = 0.52, p = 0.41 Non-contrast based two vs 3: MD = 2.05, p = 0.002 two vs 4: MD = 3.71, p < 0.001 three vs 4: MD = 1.66, p = 0.001 |
|
| Max rTBF - all reference ROIs | 1.9 (±0.8) | 1.0–3.5 | 14, 205 | 3.4 (±1.5) | 1.3–5.5 | 10, 138 | 5.1 (±2.5) | 1.6–9.5 | 13, 342 |
F = 179.2 p < 0.001 |
two vs 3 (p < 0.001) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
Contrast based two vs 3: MD = 1.91, p < 0.001 two vs 4: MD = 3.21, p < 0.001 three vs 4: MD = 1.30, p = 0.35 Non-contrast based two vs 3: MD = 0.42, p = 0.225 two vs 4: MD = 3.53, p < 0.001 three vs 4: MD = 3.11, p < 0.001 |
|
| Max rTBF - mixed | 1.7 (±0.3) | 1.3–2.0 | 3, 46 | 3.7 (±0.8) | 2.1–4.2 | 3, 41 | 5.7 (±2.7) | 2.3–9.5 | 5, 191 |
F = 60.3 p < 0.001 |
two vs 3 (p < 0.001) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
Contrast based two vs 3: MD = 2.34, p < 0.001 two vs 4: MD = 4.13, p < 0.001 three vs 4: MD = 1.80, p = 0.001 Non-contrast based two vs 3: MD = 0.85, p = 0.506 two vs 4: MD = 4.34, p < 0.001 three vs 4: MD = 3.49, p < 0.001 |
|
| Max rTBF - white matter reference | 2.1 (±0.9) | 1.0–3.5 | 8, 118 | 3.9 (±1.6) | 1.3–5.5 | 5, 69 | 4.8 (±1.9) | 1.6–7.3 | 6, 118 |
F = 100.5 p < 0.001 |
two vs 3 (p < 0.001) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
Contrast based two vs 3: MD = 1.69, p < 0.001 two vs 4: MD = 2.81, p < 0.001 three vs 4: MD = 1.13, p < 0.001 Non-contrast based two vs 3: MD = 0.15, p = 0.756 two vs 4: MD = 0.50, p = 0.167 three vs 4: MD = 0.35, p = 0.519 |
|
| Max rTBF - grey matter reference | 1.2 (±0.4) | 0.6–1.5 | 3, 47 | 1.4 (±0.3) | 1.0–1.8 | 3, 43 | 2.1 (±0.3) | 1.7–2.7 | 3, 52 |
F = 96.3 p < 0.001 |
two vs 3 (p = 0.002) two vs 4 (p < 0.001) three vs 4 (p < 0.001) |
Contrast based two vs 3: MD = 0.43, p < 0.001 two vs 4: MD = 1.14, p < 0.001 three vs 4: MD = 0.71, p < 0.001 Non-contrast based two vs 3: MD = 0.28, p < 0.001 two vs 4: MD = 0.98, p < 0.001 three vs 4: MD = 0.69, p < 0.001 |
|
ANOVA, One way analysis of variance; CBF, Cerebral blood flow; M ± SD, Mean±standard deviation; N, Number of studies followed by number of patients between studies; N/A, Current statistical test could not be performed; R, Range; ROI, Region of interest; TBF, Tumoral blood flow; rTBF, Relative tumoral blood flow.
This table shows the blood flow metrics that could be compared between different glioma grades. A one-way analysis of variance (ANOVA) and post-hoc Bonferroni tests, were undertaken to determine whether differences in mean values between glioma grades were statistically significant. This was further validated with a factorial ANOVA to control for the type of MR imaging used (contrast based or non-contrast based). With increasing glioma grade, tumoral and perilesional blood flow increased, whereas CBF decreased. All absolute flow metrics are in ml/100 g/min and all relative flow values are unitless.