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The T2 images are obtained with a long tr and te. The T2 image is sensitive to the presence of water in tissues and depicts edema as a very bright signal. Therefore, CSF or fluid containing structures such as cysts is very bright. Complicated cysts can vary in T2 images. If hemorrhagic, they can have heterogenous or even uniformly dark signal caused by a susceptibility artifact. These artifacts can be caused by metals, melanin, forms of calcium and the iron in hemoglobin. Increased tissue water from edema stands out as bright relative to the isointense soft tissue. The fast spin‐echo T2 is a common sequence, which is many times faster than the conventional spin‐echo T2 but does alter the image. Fat stays brighter on the fast spin‐echo (FSE) sequence relative to the conventional (Figure 2.9) (Table 2.2).