Pleural effusion: the thorn sign. Not a rare finding.
Eleven percent of an unselected series of 157 patients with pleural effusion showed a thorn-like protrusion of fluid at the lateral end of the minor fissure at some time during their illnesses. None of a series of 146 normal x-ray films of young patients showed this "thorn sign." The thorn sign is a useful radiographic finding of right-sided pleural effusion.
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D010996:Pleural Effusion / Q000000981:diagnostic imaging* / Q000473:pathology; D011859:Radiography; D012189:Retrospective Studies