Morphological progression of emphysema on thin-section CT: Analysis of longitudinal change in the number and size of low-attenuation clusters.
OBJECTIVE
To evaluate morphological changes in the number and size of low-attenuation clusters on computed tomography (CT) in patients with emphysema.


METHODS
In 27 patients who had follow-up CT scans for 6 months or greater, initial 27 scans and follow-up 39 scans were analyzed. The number per slice (LAN/s) and mean size (LAS) of low-attenuation clusters less than -950 HU, and total low-attenuation area below -950 HU per slice (LAA-950/s) were calculated.


RESULTS
LAS and LAA-950/s were significantly increased over time. No significant correlation was found between LAN/s and follow-up period. LAS increased in 37 of 39 (95%) follow-up scans, whereas LAN/s decreased in 17 of 39 (44%) follow-up scans.


CONCLUSIONS
On the morphological progression of emphysema, the mean size of low-attenuation clusters was significantly increased during the follow-up period, whereas no significant correlation was found between the number of low-attenuation clusters and follow-up period.
Matsuoka
Shin
S
Department of Radiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Kawasaki City, Kanagawa, 216-8511, Japan. shinma@d9.dion.ne.jp
Kurihara
Yasuyuki
Y
Yagihashi
Kunihiro
K
Nakajima
Yasuo
Y
D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D011656:Pulmonary Emphysema / Q000000981:diagnostic imaging* / Q000473:pathology; D012307:Risk Factors; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*