title: Decreased computed tomographic lung density during exacerbation of asthma.
abstract: Recently, it was shown that both mean lung density (MLD) and the relative lung area with an attenuation of <-950 HU (RA950) are related to severity of asthma in nonsmoking asthmatics. The aim of the present study was to examine whether reduced computed tomography (CT) lung density during exacerbation could change after treatment. A cross-sectional study was performed to compare CT lung density in 30 stable asthmatics, 30 unstable asthmatics and 25 control subjects. In order to investigate longitudinally the effect of treatment on decreased CT lung density, 17 asthmatics with an exacerbation were followed at the initiation of treatment and 2 months after relief. The MLD was significantly lower and the RA950 significantly higher in unstable asthmatics than in controls and stable asthmatics. Both MLD and RA950 changed significantly with administration of systemic glucocorticoid therapy. The changes in forced expiratory volume in one second correlated significantly with those in both MLD and RA950. The changes in residual volume also correlated significantly with those in both MLD and RA950. It was concluded that decreased computed tomographic lung density during an asthma exacerbation is at least partially reversible, and changes in mean lung density and the relative lung area with a radiation attenuation of <-950 HU are related to the change in forced expiratory volume in one second and residual volume.
authors.affiliation: Dept of Medicine, Misasa Medical Centre, Okayama University Medical School, Tottori, Japan. fumin@cc.okayama-u.ac.jp
authors.forename: F
authors.initials: F
authors.lastname: Mitsunobu
authors.forename: K
authors.initials: K
authors.lastname: Ashida
authors.forename: Y
authors.initials: Y
authors.lastname: Hosaki
authors.forename: H
authors.initials: H
authors.lastname: Tsugeno
authors.forename: M
authors.initials: M
authors.lastname: Okamoto
authors.forename: N
authors.initials: N
authors.lastname: Nishida
authors.forename: T
authors.initials: T
authors.lastname: Nagata
authors.forename: S
authors.initials: S
authors.lastname: Takata
authors.forename: Y
authors.initials: Y
authors.lastname: Tanizaki
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001249:Asthma / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology*; D001993:Bronchodilator Agents / Q000008:administration & dosage; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D013147:Spirometry; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed
chemical_list: D001993:Bronchodilator Agents