This image includes a classic radiographic finding. What is the name of this radiologic sign, and what is the most likely disease?

Question

Quizplus · Accepted Answer

The silhouette sign is a basic radiographic finding, explained in the book, that classically indicates the presence of pneumonia. No reticulonodular pattern is shown. The pulmonary veins in upper lobes are not bigger than in lower lobes, so congestive heart failure is not indicated. Although a single metastatic lesion abutting a pleural surface of the lingula at the heart margin could obscure a section of the cardiac border, option (D) is incorrect because to jump to that diagnosis one should see multiple lesions in the lungs.

This Image Includes a Classic Radiographic Finding