Radiology, Vol 160, 189-192, Copyright © 1986 by Radiological Society of North America
Ureteral calculi: percutaneous removal using modified basket extractors and fluoroscopy
WS Hare
Two modified helical basket extractors are described that have increased
the success rate of removing ureteral calculi using fluoroscopy from 63% to
92%. Initially a rather stiff and expandable basket with a 20-cm filiform
tip is used with coaxial catheters and sheath (stage 1). If this procedure
is unsuccessful, a basket with two long cable ends is passed from the
nephrostomy out through the urethra (stage 2). When used with coaxial
bladder catheters, this technique allows dilatation of the vesicoureteric
junction and retrograde catheterization and injection of fluids or gas to
dislodge the stone prior to extraction. In a series of 38 patients, stones
were removed in all but three (a success rate of 92%). In five cases small
stones (less than 5 mm) were not retrieved but subsequent studies were
normal. Ureteral stones were found in the abdominal ureter in 28 cases, in
the pelvic ureter in seven cases, and in multiple sites in three cases.
Stones were larger than 1 cm in 27.7% of cases. Postextraction mucosal
edema with reduced ureteral patency was common but usually cleared in 2- 3
days. Occasional complications were related to the nephrostomy.
