title: Noninvasive estimation of pulmonary capillary wedge pressure from computed radiography.
abstract: OBJECTIVE
  This study was undertaken to see if computed radiography (CR) could be used to estimate pulmonary capillary wedge pressure (PCWP).
  
  
  METHODS
  Radiographic measurements of pulmonary artery-bronchus ratios (ABR), cardiomegaly, interstitial edema, alveolar edema, and pleural effusion, obtained from portable CR images of patients admitted to an intensive care unit, were compared to hemodynamic measurements of PCWP. We prospectively predicted a normal PCWP when ABR was < or = 1.0, and an elevated PCWP when ABR was > or = 1.1.
  
  
  RESULTS
  There was a significant difference between mean ABR in those with normal PCWP (1.014 +/- 0.259) and those with elevated PCWP (1.422 +/- 0.234) (p < 0.0001). There was a positive correlation between PCWP and ABR (r = 0.38, r2 = 0.147, p = 0.0001). ABR was 95% sensitive, 86% specific, and 93% accurate in predicting PCWP (p = 0.0001). Cardiomegaly, interstitial edema, alveolar edema, and pleural effusion were not as useful.
  
  
  CONCLUSIONS
  Measurements of ABR from portable CR images can be used to estimate PCWP.
authors.affiliation: Department of Diagnostic Radiology, University of Kentucky Medical Center, Lexington 40536-0084, USA. johnwoodring@aol.com
authors.forename: J H
authors.initials: JH
authors.lastname: Woodring
authors.forename: C A
authors.initials: CA
authors.lastname: Given
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D016009:Chi-Square Distribution; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging* / Q000503:physiopathology; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D011669:Pulmonary Wedge Pressure; D013902:Radiography, Thoracic / Q000379:methods*; D011873:Radiology Information Systems; D012680:Sensitivity and Specificity