Korean J Urol.  2006 Dec;47(12):1315-1319. 10.4111/kju.2006.47.12.1315.

The Effectiveness of Non-contrast Computerized Tomography (CT) in Evaluation Ofresidual Stones after Percutaneous Nephrolithotomy

• Park J
• Hong B
• Park T
• Park H

• KMID: 2139777
• DOI: http://doi.org/10.4111/kju.2006.47.12.1315

Abstract

PURPOSE
The sensitivity of antegrade pyelogram (AGP), plain film radiography (KUB) and non-contrast, thin cut abdomen computerized tomography (CT) were prospectively compared for the detection of residual stones following a percutaneous nephrolithotomy.
MATERIALS AND METHODS
Fifty patients (53 renal units), who had undergone a percutaneous nephrolithotomy for radiopaque renal pelvis stone, as well as a non-contrast abdomen CT 1 month postoperatively, were prospectively evaluated. The number and size of residual fragments, as determined by immediate postoperative AGP, postoperative 1 month KUB and abdomen CT, were compared.
RESULTS
The stone-free rates according to the AGP, KUB and non-contrast CT were 73.6 (39/53), 62.3 (33/53) and 20.8% (11/53), respectively. In terms of clinically insignificant residual fragments (CIRFs), the success rates were 84.9 (45/53), 83.0 (44/53) and 41.5% (22/53), respectively. With respect to the residual stones (22 cases), which were detected by CT, but not by KUB, 45.5% (10 cases) were more than 4mm in size on CT, with a mean size of 7.4mm. The sensitivity for the detection of residual fragments was 47.6% for KUB compared to 100% for non-contrast CT. Seven patients received additional extracorporeal shock wave lithotripsy (ESWL) for residual stones following CT.
CONCLUSIONS
Non-contrast, thin cut abdomen CT is the most accurate imaging modality for determination of the stone-free rate following a PCNL. Non-contrast abdomen CT gives accurate information for the selection of patients who may benefit from additional ESWL treatment and for follow-up planning.

Keyword

Percutaneous nephrolithotomy; Kidney calculi; Tomography, X-ray computed

MeSH Terms

Abdomen
Follow-Up Studies
Humans
Kidney Calculi
Kidney Pelvis
Lithotripsy
Nephrostomy, Percutaneous*
Prospective Studies
Radiography
Shock
Tomography, X-Ray Computed

Figure

• 

  Fig. 1 Overall progress after a percutaneous nephrolithotomy in a total of 53 renal units. AGP: antegrade pyelogram, ESWL: extracorporeal shock wave lithotripsy, KUB: plain film radiography (kidney, ureter, bladder), CT: computerized tomography. *residual stone rates. CIRFs: clinically insignificant residual fragments.

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