title: Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes.
abstract: OBJECTIVE
  To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe.
  
  
  METHODS
  The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes.
  
  
  RESULTS
  The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03).
  
  
  CONCLUSIONS
  When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung.
  
  
  CONCLUSIONS
  Computed tomography allows assessment of the treatment of emphysema with endobronchial valves. • Endobronchial valves can reduce the volume of an emphysematous lung lobe. • Compensatory expansion is greater in ipsilateral lobes than in the contralateral lung. • Reduced air trapping is measurable by RV/TLC and smaller low attenuation area.
authors.affiliation: Center for Computer Vision and Imaging Biomarkers, Department of Radiological Sciences, David Geffen School of Medicine at UCLA, 924 Westwood Blvd, Suite 615, Los Angeles, CA 90024, USA. mbrown@mednet.ucla.edu
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Brown
authors.forename: Hyun J
authors.initials: HJ
authors.lastname: Kim
authors.forename: Fereidoun G
authors.initials: FG
authors.lastname: Abtin
authors.forename: Charlie
authors.initials: C
authors.lastname: Strange
authors.forename: Maya
authors.initials: M
authors.lastname: Galperin-Aizenberg
authors.forename: Richard
authors.initials: R
authors.lastname: Pais
authors.forename: Irene G
authors.initials: IG
authors.lastname: Da Costa
authors.forename: Arash
authors.initials: A
authors.lastname: Ordookhani
authors.forename: Daniel
authors.initials: D
authors.lastname: Chong
authors.forename: Chiayi
authors.initials: C
authors.lastname: Ni
authors.forename: Michael F
authors.initials: MF
authors.lastname: McNitt-Gray
authors.forename: Donald P
authors.initials: DP
authors.lastname: Tashkin
authors.forename: Jonathan G
authors.initials: JG
authors.lastname: Goldin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001999:Bronchoscopy; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging* / Q000601:surgery*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome