Mild depent hyperemia in the posterior lung base?

Unimportant usually: Radiologist code intended to indicate slight excess fluid in the lower part of the lung field (posterior if lying down) due to the influence of mild excess volume in the blood vessels and effect of gravity and not typical of other causes. Description implies 2 issues- > usual blood vessel volume and cause as gravity and positioning. Danger is if this is being misinterpreted by the radiologist.