Radiology, Vol 194, 399-405, Copyright © 1995 by Radiological Society of North America
Solitary pulmonary nodule: preliminary study of evaluation with incremental dynamic CT
K Yamashita, S Matsunobe, T Tsuda, T Nemoto, K Matsumoto, H Miki and J Konishi
Department of Radiology, Shiga Health Insurance Hospital, Otsu, Japan.
PURPOSE: To use incremental dynamic computed tomography (CT) to evaluate
solitary pulmonary nodules (SPNs). MATERIALS AND METHODS: Thirty-two adult
patients with SPNs less than 3 cm in diameter had 18 primary lung cancers,
10 tuberculomas, and four hamartomas. The CT numbers of the inner area of
the nodule were calculated before and 30 seconds, 2 minutes, and 5 minutes
after administration of contrast material. RESULTS: All lung cancers and
one of four hamartomas showed significantly greater enhancement (P <
.0001) than benign SPNs, which did not show enhancement (except for one
hamartoma). All lung cancers and one of four hamartomas showed complete
enhancement, one hamartoma showed peripheral enhancement, two hamartomas
and eight of 10 tuberculomas showed capsular enhancement, and two
tuberculomas showed no enhancement. CONCLUSION: Maximum attenuation of
20-60 HU appears to be a good predictor of malignancy.
