Some empyemas may possess such echogenicity and characteristics which disable their proper description. However, not diagnosing empyema would be a severe mistake.
Characteristics of motion, borders with its surrounding (especially to the adjacent lung) or use of CFM for distinguishing between the chaotic motion of fluid in the effusion and coordinated motion of consolidation with the eventual pulsation of vessels are all valuable factors helping with the diagnosis of empyema (see also case number 39).
See following case showing empyema: