Ureteral calculi

Sonography vs. excretory urography in acute flank pain

“…1) [9]. Surprisingly, all of the obstructing stones missed by sonography were calcified and evident on the plain radiographs ( …”

Transrectal ultrasonography of distal ureteral calculi: comparison with intravenous urography.

“…If ureteral obstruction is suggested with IVU in patients with suspected renal colic but plain radiographs failed to demonstrate an ureteral calculus, one of the following may be possible: (1) the obstructing lesion is a radiolucent calculus, (2) the calculus has already passed, and any residual obstruction is caused by edema at the impaction site, or (3) the lesion may be a rare cause of obstruction, such as a pedunculated tumor, sludge, or even a blood clot. 1 A large proportion of ureteral calculi (90 to 95%) are radiopaque, and the potential for demonstrating a calculus on a plain film is related to its size, its degree of radiopacity, the quality of the radiograph, and the presence of obscuring gas, bone, and phleboliths. 1 When calculi become lodged in the ureter they are most likely to do so at the levels of normal anatomic narrowings: the ureteropelvic junction; the junction of the middle and distal thirds (where the ureter crosses the iliac vessels), and the most distal portion of the ureter, where it becomes intramural in the bladder.…”

“…1 A large proportion of ureteral calculi (90 to 95%) are radiopaque, and the potential for demonstrating a calculus on a plain film is related to its size, its degree of radiopacity, the quality of the radiograph, and the presence of obscuring gas, bone, and phleboliths. 1 When calculi become lodged in the ureter they are most likely to do so at the levels of normal anatomic narrowings: the ureteropelvic junction; the junction of the middle and distal thirds (where the ureter crosses the iliac vessels), and the most distal portion of the ureter, where it becomes intramural in the bladder. Larger stones (more than 1 cm in longest dimension) tend to impact in the upper and middle third initially.…”

The Value of Renal Scan in Acute Renal Colic – A Clinical Viewpoint

“…Diagnostic accuracy using the history, clinical exami nation and the presence of RBCs in urinalysis is low [4,5], The simplest imaging examination remains the plain abdominal radiograph which can detect approximately 90% of stones [6], However, the identification of a calcif ied stone on the ordinary plain abdominal film, bears no relation to the functional status of the kidney and the degree of the hydromechanical obstruction caused by it.…”