The challenge of solitary pulmonary nodules: HRCT evaluation

Both enhancement and morphologic analysis have been shown important in the HRCT study of solitary pulmonary nodules (SPNs). In our prospective study, 25 adult patients with benign (N=8) or malignant (N=17) SPNs were examined before and after contrast agent. We obtained three serial thin section CT scans every 60 s after the onset of the injection of contrast material. All 17 malignant nodules did enhance very significantly (P < 0.001). Benign nodules did not enhance significantly (P > 0.05). Using 20 HU as a threshold for positivity of the contrast test, our sensitivity was 100%, specificity was 74%, positive predictive value was 89.5%, negative predictive value was 100%, and accuracy was 92%; test bias was 1.118. In our opinion, HRCT evaluation of SPNs is the most widely available tool to save cost and decline in morbidity in management. Copyright (C) 1997 Elsevier Science Ltd.