One-dimensional mean computed tomography value evaluation of ground-glass opacity on high-resolution images

Gen Thorac Cardiovasc Surg. 2012 Jul;60(7):425-30. doi: 10.1007/s11748-012-0066-7. Epub 2012 Jun 1.


Objective: Differentiation of atypical adenomatous hyperplasia (AAH), bronchioloalveolar carcinoma (BAC), and invasive carcinoma on computed tomography (CT) is useful for determining "follow-up or resection" strategies for lesions displaying ground-glass opacity (GGO). The purpose of this study is to evaluate one-dimensional quantitative CT values of GGO on high-resolution CT (HRCT) images using computer-aided diagnosis.

Methods: Between April 2001 and March 2010, a total of 44 nodules in 42 patients with pure or mixed GGOs ≤2 cm were retrospectively evaluated. Maximum diameter and one-dimensional mean CT (m-CT) value of the diameter were measured using a computer graphics support system (HOPE/DrABLE-EX, Fujitsu, Tokyo, Japan) that displays a CT density profile across the tumor.

Results: m-CT values were -682 ± 64 HU (range) for AAH lesions, -544 ± 179 (range) for Type A lesions, -496 ± 147 (range) for Type B lesions, and -371 ± 142 (range) for invasive lesions. AAH lesions had a significantly lower m-CT value than Type B lesions. AAH, Type A, and Type B lesions had significantly lower m-CT values than invasive lesions (p < 0.05). All seven GGO lesions with a maximum diameter ≤1 cm and m-CT value ≤-600 HU were pre-invasive lesions, while 16 of 22 (73 %) cases with maximum diameter >1 cm and m-CT value >-600 HU were invasive lesions.

Conclusion: Observation may be indicated for GGO lesions with a maximum diameter ≤1 cm and m-CT value ≤-600 HU.

MeSH terms

  • Adenocarcinoma / diagnostic imaging*
  • Adenocarcinoma / pathology
  • Adenocarcinoma of Lung
  • Adenocarcinoma, Bronchiolo-Alveolar / diagnostic imaging*
  • Adenocarcinoma, Bronchiolo-Alveolar / pathology
  • Adenoma / diagnostic imaging*
  • Adenoma / pathology
  • Adult
  • Aged
  • Aged, 80 and over
  • Diagnosis, Differential
  • Female
  • Humans
  • Hyperplasia
  • Japan
  • Lung Neoplasms / diagnostic imaging*
  • Lung Neoplasms / pathology
  • Male
  • Middle Aged
  • Neoplasm Invasiveness
  • Predictive Value of Tests
  • Prognosis
  • Radiographic Image Interpretation, Computer-Assisted*
  • Tomography, X-Ray Computed*