The soft-tissue rim sign is used to distinguish a ureteric calculus from a phlebolith. The former appears as a calcific density with a surrounding rim of soft tissue which represents the oedematous ureteric wall. Phleboliths on the other hand usually have imperceptible walls (although up to 8% may have a soft tissue rim sign 2) but may have a comet-tail sign.
This sign may be absent in cases of a larger ( >4mm) calculus or in cases of a uretrovesical calculus. 3
- 1. Guest AR, Cohan RH, Korobkin M et-al. Assessment of the clinical utility of the rim and comet-tail signs in differentiating ureteral stones from phleboliths. AJR Am J Roentgenol. 2001;177 (6): 1285-91. AJR Am J Roentgenol (full text) - Pubmed citation
- 2. Heneghan JP, Dalrymple NC, Verga M et-al. Soft-tissue "rim" sign in the diagnosis of ureteral calculi with use of unenhanced helical CT. Radiology. 1997;202 (3): 709-11. Radiology (abstract) - Pubmed citation
- 3. Dyer RB, Chen MY, Zagoria RJ. Classic signs in uroradiology. Radiographics. 2004;24 Suppl 1 (suppl 1): S247-80. Radiographics (full text) - doi:10.1148/rg.24si045509 - Pubmed citation
- 4. Lupetin AR, Mainwaring BL, Daffner RH. CT diagnosis of renal artery injury caused by blunt abdominal trauma. AJR Am J Roentgenol. 1989;153 (5): 1065-8. doi:10.2214/ajr.153.5.1065 - Pubmed citation