LUNG PERFUSION CT

Pathological Perfusion CT:
in the low area of the left lower lobe, a region of interest (blue point) was placed to measure parenchymal enhancement of the lung.
CT attenuation value was 36.2 Hounsfield units.
In the right normal opposite site (yellow point), CT attenuation value was 73.3 Hounsfield units.
The left low-attenuation area suggested reduced pulmonary perfusion (due to a blood clot in the interlobar left pulmonary artery).