5 Minute Sono - Kidney Stones

Identifying ureterolithiasis via ultrasound relies primarily on detecting secondary signs of obstruction, specifically hydronephrosis. Effective imaging requires a phased array or curvilinear transducer placed in a coronal plane, with slight rotation to avoid rib shadows. Hydronephrosis is characterized by hypoechoic fluid expanding from the renal pelvis toward the periphery, categorized as mild, moderate, or severe based on the degree of pelvic dilation and pyramid coalescence. While direct visualization of stones is often hindered by bowel gas, obstructing stones typically appear as hyperechoic structures with distinct posterior shadowing. Diagnostic accuracy improves by observing the "twinkling artifact" on color Doppler or identifying absent ureteral jets in the bladder over a five-minute period. Differentiating these findings from peripheral renal cysts or solid masses like renal cell carcinoma is essential for accurate diagnosis.