Comparison of Computerized Spiral Tomography with Ultrasonography for Detection of Ureteral Calculi

Abstract

Objectives: We aimed to compare accuracy levels of ultrasonography and spiral computerized tomography for detection of the ureteral calculi in patients admitted to the emergency department with flank pain.
Methods: The patients presented with either unilateral or bilateral flank pain to the emergency department over a four-month period and who were suspected to be renal colic were included into the study. All of the study patients with distended bladder after hydration had ultrasonography (USG) and unhanced helical computerized tomography (UHCT) performed by two independent radiologists.
Results: Of the 76 patients with flank pain, CT detected ureteral calculi in 47 out of 48 patients (97.9%) and USG detected ureteral calculi in 34 out of the 48 patients (70.83%). CT detected uretral calculi in 14 patients which was not detected by USG. CT also detected renal calculi in 7 patients which was not detected by USG. A kappa value of 0.62 (p<0.001) was determined, indicating a moderate concordance between CT and USG in detecting ureteral calculi. Also a kappa value of 0.65 (p<0.001) was determined in the overall diagnostic performance of the both imaging tools in detecting renal calculi.
Conclusions: Computerized tomography is better than ultrasonography in detecting urinary calculus in patients presented to the emergency department with flank pain. However, as a bedside, non-invasive and non-ionized tool, USG should be preffered as the first line diagnostic choice in ED for detecting urinary calculus. CT should be used as an second choice in patients with negative USG exam in ED.