title: Ultrasmall pulmonary opacities on multidetector-row high-resolution computed tomography: a prospective radiologic-pathologic examination.
abstract: 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.
authors.affiliation: Department of Radiology, Niigata University Hospital, Niigata, Japan. iskw@med.niigata-u.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishikawa
authors.forename: Naoya
authors.initials: N
authors.lastname: Koizumi
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Morita
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Tani
authors.forename: Masanori
authors.initials: M
authors.lastname: Tsuchida
authors.forename: Hajime
authors.initials: H
authors.lastname: Umezu
authors.forename: Makoto
authors.initials: M
authors.lastname: Naito
authors.forename: Keisuke
authors.initials: K
authors.lastname: Sasai
mesh_terms: 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*