Vascular Phenotyping of Brain Tumors using Magnetic Resonance Microscopy (μMRI)

Correction to: Journal of Cerebral Blood Flow & Metabolism (2011) 31, 1623–1636; doi: 10.1038/jcbfm.2011.17

Following the publication of this article, the authors noted errors in the following graphs in the article. The corrected graphs and accompanying text appear below:

Results

Morphologic Characterization of the Vascular Phenotype

Figures 2A and 2B show the manually segmented tumor and contralateral ROIs overlaid on the MGE μMRI data, and Figures 2C and 2D show the resultant radius-encoded vascular maps for representative D12 and D17 9L tumor-bearing brains, respectively. For tumor and contralateral ROIs of each brain, six morphologic parameters were computed as summarized in Figures 3A–3H: median vessel length, average vessel radius, MVD, L_V, FV, and median vessel tortuosity. Figures 3A–3H show that with the exception of D12 L_V, D17 radius and D17 tortuosity, there was a significant (P < 0.05) difference between these parameters for tumor and contralateral ROIs. For D17 brains, L_V was significantly greater in tumors than in contralateral ROIs (Figure 3D); for D12 brains, radius and tortuosity were significantly greater in tumors (Figures 3B and 3F). For both D12 and D17 groups, MVD and FV were elevated in tumor with regard to contralateral ROIs (Figures 3C and 3E), whereas vessel length exhibited the opposite relationship (Figure 3A). Finally, L_V and FV were found to be significantly higher in D12 tumors than in D17 tumors (Figures 3D and 3E).

Zonal Analysis of Tumor Regions of Interest

In both D12 and D17 tumors, ADC was significantly lower in the rim than in the two inner zones (Figures 4E and 4G). In contrast, there was no significant difference in FA across the three zones in either D12 or D17 tumors (Figures 4F and 4H). Vessel length and radius did not vary significantly between zones in D12 tumors. However, in the core of D17 tumors, vessel length was greater than in the other two zones. In D12 tumors, MVD was significantly lower in the rim than in the core, L_V did not vary significantly between zones, and FV decreased significantly from the core to the intermediate to the rim (Figures 5A–5C). In contrast, in D17 tumors, MVD and L_V were lower in the core than in the other zones, and FV was lower in the core than in the intermediate zone (Figures 5D–5F). No significant variation in tortuosity was seen between zones for either D12 or D17 tumors.

Discussion

There was no significant difference in MVD between D12 and D17 tumors (pp 8 and 9). There was no significant difference in FA between the D17 tumor rim and core (p 10).