Frontal Chest X-ray (IMAGE) Radiological Society of North America Caption Frontal chest X-ray shows a small nodular opacity (arrow) in the left upper lung zone. Axial, non-contrast, low-dose chest CT scan shows a 9-mm solid nodule (arrow) in the left upper lobe. Credit RSNA/Radiology Usage Restrictions May use with credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.