title: Lung perfused blood volume images with dual-energy computed tomography for chronic thromboembolic pulmonary hypertension: correlation to scintigraphy with single-photon emission computed tomography.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the feasibility and diagnostic utility of lung perfused blood volume (LPBV) images generated by dual-energy computed tomography (CT), as compared with pulmonary perfusion scintigraphy, for patients with chronic thromboembolic pulmonary hypertension.
  
  
  METHODS
  Patients (n = 51) with chronic pulmonary thromboembolic embolism were examined by dual-source CT in dual-energy mode. Lung perfused blood volume images were generated by analysis of the iodine content of the lung parenchyma using dual-energy data. Pulmonary perfusion defects were evaluated on a segment-by-segment basis in images obtained by both LPBV and pulmonary scintigraphy. Findings suggestive of chronic thromboembolic pulmonary hypertension in CT pulmonary angiography were analyzed.
  
  
  RESULTS
  All examinations were acquired without complications, and the contrast enhancement of the pulmonary artery was sufficient for diagnosis of vascular thromboses. In the LPBV images, in 76 (8.3%) of 918 segments, it was difficult to assess perfusion because of artifacts. The agreement between the 2 modalities was good (κ = 0.70). The sensitivity of LPBV in detecting perfusion defects was 96%; the specificity was 76%; the positive predictive value was 94%, and the negative predictive value was 29%.
  
  
  CONCLUSIONS
  Lung perfused blood volume imaging by dual-energy CT is feasible for the evaluation of pulmonary perfusion and is comparable to pulmonary scintigraphy. It is possible to evaluate vessels and pulmonary perfusion with CT pulmonary angiography and LPBV images and to assess pulmonary perfusion more definitively in diagnosing chronic pulmonary thromboembolic embolism.
authors.affiliation: Department of Radiology, National Cerebral and Cardiovascular Center, Osaka, Japan. tnakazawa1230@gmail.com
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Nakazawa
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Hori
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kiso
authors.forename: Masahiro
authors.initials: M
authors.lastname: Higashi
authors.forename: Toshihide
authors.initials: T
authors.lastname: Itoh
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Naito
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D001810:Blood Volume; D006328:Cardiac Catheterization; D002908:Chronic Disease; D003287:Contrast Media; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011857:Radiographic Image Interpretation, Computer-Assisted; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media