Soft tissue Rim sign - Ureteric calculi
A soft tissue rim surrounding an intraureteral stone (arrow).
_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 but may have a comet-tail sign.
The soft tissue rim sign describes the rim of oedematous ureteric wall in immediate contact with an obstructing intraureteral stone. It has been specifically defined as a 1–2 mm rim of soft tissue attenuation (20–40 HU) surrounding the stone (figure) . Stones at the VUJ, however, are surrounded by abundant bladder wall muscle, and the rim sign will not be apparent.
The soft tissue rim sign describes the rim of oedematous ureteric wall in immediate contact with an obstructing intraureteral stone. It has been specifically defined as a 1–2 mm rim of soft tissue attenuation (20–40 HU) surrounding the stone (figure) . Stones at the VUJ, however, are surrounded by abundant bladder wall muscle, and the rim sign will not be apparent.