Relationship of spontaneous passage of ureteral calculi to stone size and location as revealed by unenhanced helical CT.

Abstract in brief

• The study found that the likelihood of ureteral stones passing spontaneously depends on both their size and location, with smaller stones and those located further down the ureter (closer to the bladder) having a higher chance of passing without intervention.
• Specifically, stones smaller than 2 mm have an 87% passage rate, while stones larger than 9 mm have only a 25% chance to pass on their own, and stones in the distal ureter or at the ureterovesical junction are more likely to pass spontaneously.
• The findings using unenhanced CT are consistent with previous studies based on radiography, confirming that CT is an effective tool for predicting stone passage based on size and location.