What is the normal enhancement pattern of the spleen?
During the arterial phase of enhancement (≈20 to 35 seconds after intravenous [IV] contrast administration), the spleen typically appears to have alternating bands of low and high CT attenuation or T1-weighted MRI signal intensity known as the arciform enhancement pattern ( Figure 29-2, A ). Variation from this pattern suggests presence of diffuse splenic disease. During the venous phase of enhancement (≈50 to 75 seconds after IV contrast administration), contrast material equilibrates in the spleen such that homogeneous intense enhancement is observed
