The objective of this study was to clarify the cause and clinical significance of a large number of @entity1467 ( @entity1467 ) observed on the dorsal side of the right hepatic lobe on abdominal ultrasound (US). 2000 abdominal US examinations were evaluated to investigate the frequency and number of @entity1467 behind the right lobe of the liver. In this study, @entity1467 observed by subcostal or intercostal US were described as the "aurora sign" when they were numerous. US findings were correlated with high resolution CT or three-dimensional CT of the right lung base. Experimental study was also performed to investigate the mechanism of the aurora sign. The results were as follows. (1). Aurora sign was noted in 43 @entity1 . In 37 of these 43 @entity1 (86.0%), chest CT or plain radiography revealed diffuse interstitial changes in the right lower lung field. Three-dimensional CT of the lung and the experimental model revealed that the aurora sign derived from the irregularity of air spaces immediately below the pleura associated with @entity358 . (2). One or more bands of @entity1467 were observed in 907 of the 2000 @entity1 (45.4%). Of 177 @entity1 with @entity1560 , @entity1467 was observed in 14 (7.9%), while of the 1823 @entity1 with no @entity1560 , @entity1467 was observed in 893 (49.0%). The frequency of @entity1467 was significantly different (p<0.001) between the @entity1 with and without @entity1560 . In conclusion, @entity358 should be suspected when the aurora sign is noted on the dorsal side of the right hepatic lobe. However, RAs are rare in @entity1 with @entity1560 .

The aurora sign: an ultrasonographic sign suggesting XXXX .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1467 :: ('MESH:D004314', 'Disease') :: ['RA', 'ring-down artefact'] @entity1560 :: ('MESH:D005234', 'Disease') :: ['fatty liver'] @entity358 :: ('MESH:D008171', 'Disease') :: ['interstitial pulmonary disorders', 'parenchymal lung disease']
@entity358 :: (MESH:D008171,Disease) :: ['parenchymal lung disease']
