Solitary Pulmonary Nodule Click here for more detailed information about Solitary Pulmonary Nodule A solitary pulmonary nodule or SPN is defined as a discrete, well-marginated, rounded opacity less than or equal to 3 cm in diameter. It has to be completely surrounded by lung parenchyma, does not touch the hilum or mediastinum and is not associated with adenopathy, atelectasis or pleural effusion. The differential diagnosis of SPN is basically the same as of a mass except that the chance of malignancy increases with the size of the lesion. Lesions smaller than 3 cm, i.e. SPN's are most commonly benign granulomas, while lesions larger than 3 cm are treated as malignancies until proven otherwise and are called masses. #Diagnosis #Radiology #SPN #SolitaryPulmonaryNodule #Differential #RadiologyAssistant
