Volume histogram analysis for lung thin-section computed tomography: differentiation between usual interstitial pneumonia and nonspecific interstitial pneumonia.
OBJECTIVE
The aim of this study was to evaluate volume histogram analysis between usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP).


METHODS
Sixty cases (UIP, n = 22; NSIP, n = 38) were evaluated retrospectively. Three parameters (contrast, variance, and entropy) were calculated in 3 types of regions of interest (ROIs): (a) whole lung, (b) right lower lobe, and (c) cubic ROIs. To evaluate the influence of extent of abnormal findings, the numbers of voxels with low or high density in whole lung were compared with the 3 parameters.


RESULTS
No significant differences were observed between the ROIs of whole lung and the right lower lobe. In all cubic ROIs, entropy in UIP was larger than that in NSIP (P < 0.001). The numbers of voxels with low-density areas significantly correlated with the values of contrast and entropy, whereas those with high-density areas significantly correlated with all 3 parameters.


CONCLUSIONS
Volume histogram analysis for cubic ROIs may be feasible for differentiating between UIP and NSIP.
Department of Radiology, Osaka University Graduate School of Medicine, Osaka, Japan. h-sumikawa@radiol.med.osaka-u.ac.jp
Hiromitsu
H
Sumikawa
Takeshi
T
Johkoh
Shuji
S
Yamamoto
Mamoru
M
Oota
Takashi
T
Ueguchi
Yuji
Y
Ogata
Mitsuhiro
M
Matsumoto
Yuka
Y
Fujita
Javzandulam
J
Natsag
Atsuo
A
Inoue
Naoki
N
Mihara
Osamu
O
Honda
Noriyuki
N
Tomiyama
Hironobu
H
Nakamura
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods* / Q000706:statistics & numerical data; D008168:Lung / Q000000981:diagnostic imaging*; D017563:Lung Diseases, Interstitial / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D011856:Radiographic Image Enhancement / Q000379:methods; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000706:statistics & numerical data