Microvasculatures in healthy cortical tissue, in untreated and in antiangiogenically treated glioblastoma multiforme are compared in a mouse model. From T2-maps, the information entropy is determined for each tissue type. In addition, capillaries are directly imaged through in vivo multiphoton microscopy to obtain sets of microvascular parameters. The T2-entropy is lowest in healthy tissue and significantly higher in glioblastoma, with a moderate decrease in treated tumors. Several vascular characteristics correlate with the T2-entropy. The correlations provide insight into the influence of microvasculature on MR-dephasing.