Rim Sign

Rim Sign

Any of a number of imaging signs in which one rounded mass is visually superimposed on a larger round mass, such that the periphery of the larger mass is more readily visible
Gastroenterology An opacification of the margin of a congenital choledochal cyst seen by a plain abdominal film
Gynaecology An attenuated annular radiopacity seen in the pelvis by infusion urography corresponding to cystic pelvic mass(es), usually of ovarian origin; a similar finding may occur in benign unilateral pelvic masses with a smooth serosal contour—e.g., fibroma-thecomas, cystadenofibromas
Nephrology A series of connected, overlapping physaliferous rims seen in the nephrogram phase of selective renal angiography of advanced hydronephrosis, where attenuated curved vascular tissue surrounds dilated calices of the renal pelvis
Orthopaedics (1) Snowcap sign (2) A finding on a plain film of a posterior dislocation of the shoulder, which is often accompanied by a fracture of the medial portion of the humeral head; in a positive rim sign, there is a widening—6 mm between the anterior rim of the glenoid fossa and the medial margin/aspect of the humeral head. The sign may also be present in posterior dislocation because the normal glenoid fossa faces as much anteriorly as it does laterally. Because the dislocated humeral head rests against the posterior glenoid rim, the space between the anterior rim and the humeral head appears increased
Paediatrics An annular, attenuated periadrenal radiopacity seen in neonatal haemorrhage in this region, seen by high-dose excretory urography

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rim sign

Imaging GI tract An opacification of the margin of a congenital choledochal cyst seen by a plain abdominal film Gynecology An attenuated annular radiopacity seen in the pelvis by infusion urography corresponding to cystic pelvic mass(es), usually of ovarian origin; a similar finding may occur in benign unilateral pelvic masses with a smooth serosal contour–eg, fibroma-thecomas, cystadenofibromas Orthopedics A finding on a plain film of a posterior dislocation of the shoulder, which is often accompanied by a fracture of the medial portion of the humeral head; in a positive RS, there is a widening–≥ 6 mm between the anterior rim of the glenoid fossa and the medial margin of the humerus Pediatrics An annular, attenuated periadrenal radiopacity seen in neonatal hemorrhage in this region, seen by high-dose excretory urography Urology A series of connected, overlapping physaliferous rims seen in the nephrogram phase of selective renal angiography of advanced hydronephrosis, where attenuated curved vascular tissue surrounds dilated calices of the renal pelvis