ABSTRACT
Purpose: Dual-energy
CT (DECT) can be used for quantification of lung perfusion blood volume (PBV), allowing
objective evaluation. However, no reports have investigated pulmonary perfusion
correlating with pulmonary artery pressure (PAP) in patients with chronic
pulmonary diseases. The purpose was to evaluate automated quantification of the
lung PBV using dual-energy CT, and its correlation with PAP. Methods: 274
patients who underwent echocardiography within two weeks also underwent CT. The
population was divided into high (≥40 mmHg) and low (<40 mmHg) estimated systolic
PAP (sPAP) groups (n = 63 and n = 211, respectively). We retrospectively eva-luated
the lung PBV using Syngo software, and correlations between the lung PBV and
estimated sPAP. Results: Lung PBV values were 25.0 ± 9.6 and 29.0 ± 9.3
Hounsfield units (HU) in high and low sPAP groups, respectively, with a
significant difference between them (p = 0.003). In the high sPAP group with
underlying lung diseases (n = 15), chronic thromboembolism (n = 25), pulmonary
artery stenosis (n = 12), and left heart failure (n = 11), using the Dana Point
classification system, lung PBV values were 18.6 ± 1.6, 25.1 ± 4.5, 25.8 ± 4.5,
and 32.7 ± 9.4 HU, respectively. There were significant differences in
quantification of the lung PBV among them. The mean sPAP of subjects with left
heart failure was significantly higher than in the others. In subjects with
left heart failure, a positive correlation between the lung PBV value and sPAP
was noted (R = 0.721, p < 0.0001). Conclusions: Automated quantification of
the lung PBV may estimate the high sPAP. The lung PBV may contribute to
clarifying the etiology of a high PAP due to left heart failure.