title: Quantitative computed tomography assessment of graft-versus-host disease-related bronchiolitis obliterans in children: A pilot feasibility study.
abstract: OBJECTIVE
  To suggest a simple method that can quantify air trapping from chest CT in children with graft-versus-host disease (GVHD)-related bronchiolitis obliterans (BO).
  
  
  METHODS
  This institutional review board-approved retrospective study included eight GVHD-related BO patients (age, 6 - 17 years) who underwent both 31 CTs of variable settings and pulmonary function tests (PFT). The attenuation values of lung parenchyma in normal (An) and air trapping (Aa) areas were obtained. Individualized threshold [(An + Aa)/2] and fixed threshold of -950 HU were set for air trapping quantification. Spearman correlation analysis and generalized linear mixed models were used for statistical analysis.
  
  
  RESULTS
  The mean value of individualized threshold was -830.2 ± 48.3 HU. The mean air trapping lung volume percentage with individualized threshold and -950 HU were 45.4 ± 18.9% and 1.4 ± 1.9%, respectively. The air trapping lung volume percentage with individualized threshold showed a significant negative correlation with the PFT of FEV1/FVC% in all data (γ = -0.795, P < .001) and in the correction of repetition (γ = -0.837, P = .010).
  
  
  CONCLUSIONS
  We suggest a simple and individualized threshold attenuation setting method for air trapping quantification insusceptible to CT imaging protocols or respiratory phase control in children with GVHD-related BO.
  
  
  CONCLUSIONS
  • Simple and individualized threshold attenuation setting for air trapping quantification is possible. • Individualized threshold attenuation setting is insusceptible to CT imaging protocols or respiratory phase control. • CT air trapping quantification correlates with PFT of pulmonary obstruction.
authors: Department of Radiology and Research Institute of Radiological Science, Severance Children's Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, Korea, 120-752.
authors: Hyun Gi
authors: HG
authors: Kim
authors: Hyun Joo
authors: HJ
authors: Shin
authors: Yoon Hee
authors: YH
authors: Kim
authors: Myung Hyun
authors: MH
authors: Sohn
authors: Chuhl Joo
authors: CJ
authors: Lyu
authors: Myung-Joon
authors: MJ
authors: Kim
authors: Kyung Won
authors: KW
authors: Kim
authors: Mi-Jung
authors: MJ
authors: Lee
mesh_terms: D000293:Adolescent; D000388:Air; D001989:Bronchiolitis Obliterans / Q000000981:diagnostic imaging*; D002648:Child; D005240:Feasibility Studies; D005260:Female; D005541:Forced Expiratory Volume; D006086:Graft vs Host Disease / Q000000981:diagnostic imaging*; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D010865:Pilot Projects; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods