title: High-resolution CT findings in patients with near-fatal asthma: comparison of patients with mild-to-severe asthma and normal control subjects and changes in airway abnormalities following steroid treatment.
abstract: OBJECTIVE
  Extensive airway inflammation and excessive mucus production are implicated in deaths from asthma. High-resolution CT (HRCT) can be used to image both large and small airway abnormalities in asthmatics. The aims of this study were to clarify the distinction of HRCT features between near-fatal asthma (NFA) and non-NFA, and to evaluate serial follow-up HRCT scans of patients with NFA.
  
  
  METHODS
  Abnormalities of the large airway (bronchial wall thickness) and small airways (prominence of centrilobular structures and air trapping) were measured semiquantitatively on HRCT scans of 24 non-NFA, 16 NFA, and 16 control subjects. In addition, these abnormalities were reevaluated after intensive and relatively long-term (> 6 months) treatment with inhaled corticosteroids.
  
  
  RESULTS
  Prominence of centrilobular structures was observed in 36% of mild asthma cases, in 70% of moderate-to-severe asthma cases, and in 100% of NFA cases. Prominence of centrilobular structures, but neither bronchial wall thickness nor the area of air trapping, was significantly increased in NFA, as compared with mild or moderate-to-severe asthma (p < 0.05). In the seven non-NFA and five NFA patients who underwent follow-up HRCT scans, only bronchial wall thickness was decreased significantly in the NFA cases (p < 0.05), while bronchial wall thickness and the prominence of centrilobular structures were significantly decreased in the non-NFA cases. These small airway abnormalities were partially reversible in the both groups. Residual prominence of centrilobular structures after long-term inhaled corticosteroid treatment was significantly higher in NFA than non-NFA patients.
  
  
  CONCLUSIONS
  The results of our study indicate that extensive small airway abnormalities may be associated with NFA, and that these abnormalities are partially reversible after the successful control of asthma symptoms.
authors.affiliation: Division of Allergy and Respiratory Medicine, Soonchunhyang University Hospital, 1174 Jung-Dong, Wonmi-Gu, Bucheon, Gyeonggi-Do 420-767, Republic of Korea.
authors.forename: Young-Mok
authors.initials: YM
authors.lastname: Lee
authors.forename: Jai-Soung
authors.initials: JS
authors.lastname: Park
authors.forename: Jung-Hwa
authors.initials: JH
authors.lastname: Hwang
authors.forename: Sung-Woo
authors.initials: SW
authors.lastname: Park
authors.forename: Soo-taek
authors.initials: ST
authors.lastname: Uh
authors.forename: Yong-Hoon
authors.initials: YH
authors.lastname: Kim
authors.forename: Choon-Sik
authors.initials: CS
authors.lastname: Park
mesh_terms: D000208:Acute Disease; D001249:Asthma / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology; D016535:Bronchial Hyperreactivity; D001995:Bronchography; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D012131:Respiratory Insufficiency / Q000209:etiology; D014057:Tomography, X-Ray Computed
chemical_list: D005938:Glucocorticoids