MRIs are obtained as thin slices in the axial, coronal, or sagittal planes. T1 weighting is a technique used to acquire images in which fluid appears dark/black. Gray matter appears dark gray, and white matter is lighter than gray matter. The appearance of blood vessels is variable. In the series that follows, the large vessels, like the carotid arteries and circle of Willis arteries are white. The subcutaneous fat is white.