In MRI, which type of imaging sequence typically shows restricted diffusion clearly?

Diffusion Weighted Imaging (DWI) is specifically designed to highlight areas of restricted diffusion within tissues. This imaging technique is sensitive to the movement of water molecules, and it can effectively reveal abnormalities in tissues where water diffusion is limited, such as in stroke, tumors, or infections. In DWI, the MRI signal is influenced by the diffusion of water molecules in the tissue, making it an excellent tool for identifying conditions that cause alterations in cellular structure and density, leading to restricted movement of water.

In contrast, T1 and T2 Weighted Imaging are more general imaging sequences that provide information on tissue contrast and characteristics but do not specifically emphasize diffusion dynamics. T1 Weighted Imaging highlights fat and provides good anatomical detail, while T2 Weighted Imaging shows edema and other fluid-related conditions, but neither is as sensitive to diffusion as DWI. Dynamic Contrast-Enhanced Imaging involves the use of contrast agents to assess tumor perfusion and vascular permeability, which is not focused on the diffusion properties of water in tissues.

Therefore, DWI is the most appropriate sequence for clearly demonstrating restricted diffusion, making it the correct answer.