The cerebral angiome: High resolution MicroCT imaging of the whole brain cerebrovasculature in female and male mice

Hierarchical imaging and computational analysis of three-dimensional vascular network architecture in the entire postnatal and adult mouse brain

“…Regarding the brain vasculature, vascular corrosion casting is a well-established technique to study cerebrovascular anatomy in physiological settings in mice 40,99–107 . Angiogenesis and vascular network morphology have previously been described using vascular corrosion casting in the adult healthy mouse brain 27,39 , for instance using brain-specific VEGF 165 -overexpressing mice (age: 16±2 weeks = P112) to study the effects of this pro-angiogenic stimulus on the adult brain vascular network 108 .…”

“…For example, here we have an isotropic voxel size of 0.65 µm, compared to 1.625 µm x 1.625 µm x 3 µm achieved through multi-dye vessel staining, tissue clearing, and 3D LSFM in 145 . For analysis, anisotropic voxels are often resampled to isotropic voxel size corresponding to the lowest resolution component, as was also done in 145 , resulting in isotropic voxel size of 3 µm for convolutional neural network vessel segmentation and subsequent analysis of the vasculature of the whole mouse brain 145 . Micro CT imaging with use of intravascular contrast agents is used both in-vivo and ex-vivo and made it possible to image the vasculature in whole organs in 3 dimensions with increasing resolution 107,147–150 . Ex-vivo, vascular corrosion casts have shown to be an excellent method to investigate brain vasculature in particular 40,104,106,107,109,110,120 .…”

“…For analysis, anisotropic voxels are often resampled to isotropic voxel size corresponding to the lowest resolution component, as was also done in 145 , resulting in isotropic voxel size of 3 µm for convolutional neural network vessel segmentation and subsequent analysis of the vasculature of the whole mouse brain 145 . Micro CT imaging with use of intravascular contrast agents is used both in-vivo and ex-vivo and made it possible to image the vasculature in whole organs in 3 dimensions with increasing resolution 107,147–150 . Ex-vivo, vascular corrosion casts have shown to be an excellent method to investigate brain vasculature in particular 40,104,106,107,109,110,120 . Corrosion casting, in combination with recent advances in imaging techniques – both for SRμCT and desktop μCT setups –, as used in this protocol, results in a resolution that is at least 3 times higher (0.65 μm vs 2 μm pixel size) than another recent paper that used a similar approach to study the mouse brain vasculature 107 . The protocol used here allows to quantitatively describe in detail the postnatal and adult CNS blood vessel network down to the capillary level, (Figures 5–11 and Extended Data Figures 3–9), including visualization and quantification of vessel directionality in the X, Y, Z planes (Figure 10, and Supplementary Figures 6–9,14), which provides important additional information and – to the best of our knowledge – has not been addressed so far.…”

“…Ex-vivo, vascular corrosion casts have shown to be an excellent method to investigate brain vasculature in particular 40,104,106,107,109,110,120 . Corrosion casting, in combination with recent advances in imaging techniques – both for SRμCT and desktop μCT setups –, as used in this protocol, results in a resolution that is at least 3 times higher (0.65 μm vs 2 μm pixel size) than another recent paper that used a similar approach to study the mouse brain vasculature 107 . The protocol used here allows to quantitatively describe in detail the postnatal and adult CNS blood vessel network down to the capillary level, (Figures 5–11 and Extended Data Figures 3–9), including visualization and quantification of vessel directionality in the X, Y, Z planes (Figure 10, and Supplementary Figures 6–9,14), which provides important additional information and – to the best of our knowledge – has not been addressed so far. Moreover, it permits to distinguish between capillaries and non-capillaries using clearly defined morphological parameters.…”

“…Micro CT imaging with use of intravascular contrast agents is used both in-vivo and ex-vivo and made it possible to image the vasculature in whole organs in 3 dimensions with increasing resolution 107,147–150 . Ex-vivo, vascular corrosion casts have shown to be an excellent method to investigate brain vasculature in particular 40,104,106,107,109,110,120 . Corrosion casting, in combination with recent advances in imaging techniques – both for SRμCT and desktop μCT setups –, as used in this protocol, results in a resolution that is at least 3 times higher (0.65 μm vs 2 μm pixel size) than another recent paper that used a similar approach to study the mouse brain vasculature 107 .…”