Are there CT and MRI features that can distinguish between transudative and exudative ascites?
Transudative ascites generally has water attenuation, low signal intensity on T1-weighted images, and very high signal intensity on T2-weighted images similar to fluid elsewhere in the body, is nonloculated, and tends to accumulate to a greater degree in the greater sac than in the lesser sac.
Exudative ascites has variably increased attenuation relative to fluid elsewhere in the body, variably increased signal intensity on T1-weighted images, and variably decreased signal intensity on T2-weighted images. Loculations, peritoneal thickening, and peritoneal enhancement are commonly seen as well. Fluid accumulation to a similar degree in both the greater and larger sacs favors a malignant etiology of ascites, whereas fluid accumulation to a greater degree in the lesser sac than in the greater sac favors inflammatory ascites related to pancreatitis.