(1) Regional oligemia is usually associated with reduced blood flow in the oligemic area.

(2) Result:Chest X-ray showed pulmonary oligemia, right atrial and left ventricular enlargement.

(3) Pathophysiology . —Oligemia is a reduction in pulmonary blood volume. Most frequently, this reduction is regional, but occasionally it is generalized.

(4) Deficiency of circulating blood volume, both cellular elements and fluid, is called oligemia.

(5) Results: Patchy consolidation, ground glass opacity, wedge-shaped shadow, "mosaic oligemia" etc can be seen on plain CT.