Ultrasmall pulmonary opacities on multidetector-row high-resolution computed tomography: a prospective radiologic-pathologic examination.
OBJECTIVE
To clarify the pathologic findings of ultrasmall pulmonary opacities (5 mm or smaller in diameter) found on multidetector-row high-resolution computed tomography (MD-HRCT).


METHODS
Ten lobes in 10 patients were included in this study. Each lobe had a primary lung tumor and was removed surgically. Two thoracic radiologists noted any tiny nonlinear opacity on preoperative MD-HRCT films (1.25-mm thickness) covering the whole lobe. Pathologic findings of detected opacities were evaluated macroscopically and microscopically.


RESULTS
Among 139 ultrasmall opacities 5 mm or smaller in diameter, 94 corresponded to normal anatomic structures (partial volume averaging or motion artifact), 36 corresponded to pathologic abnormalities, and 9 were unidentified. Histologic diagnoses of 36 pathologic abnormalities were inflammatory lesions (n = 16), intrapulmonary lymph nodes (IPLN; n = 7), atypical adenomatous hyperplasia (AAH; n = 7), bronchioloalveolar carcinoma (BAC; n = 5), and another neoplastic lesion (n = 1).


CONCLUSIONS
Tiny pulmonary lesions, such as AAHs, BACs, and IPLNs, were identified among ultrasmall opacities found on MD-HRCT.
Ishikawa
Hiroyuki
H
Department of Radiology, Niigata University Hospital, Niigata, Japan. iskw@med.niigata-u.ac.jp
Koizumi
Naoya
N
Morita
Tetsuro
T
Tani
Yoshiko
Y
Tsuchida
Masanori
M
Umezu
Hajime
H
Naito
Makoto
M
Sasai
Keisuke
K
D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000000981:diagnostic imaging* / Q000473:pathology; D018255:Adenomatosis, Pulmonary / Q000000981:diagnostic imaging* / Q000473:pathology; D000328:Adult; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000000981:diagnostic imaging / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*