Comparison by SPECT of Renal Scars after Extracorporeal Shock Wave Lithotripsy and Percutaneous Nephrolithotomy

Abstract

Some renal calculi are borderline indications for either extracorporeal shock wave lithotripsy (ESWL) or percutaneous nephrolithotomy (PCNL). Our purpose was to quantify by single photon emission computed tomography (SPECT) the parenchymal lesions of these two procedures to make the choice easier. The SPECT study was done before and 30 days after the stone treatment. The scan was carried out 10 hours after injection of 99mTc-DMSA using a GE400 rotative gamma camera, which data were reconstructed in three planes. The local uptake and scar of the treated area were evaluated in 22 patients with symptomatic kidney stones without previous treatment or renal failure. Twelve patients (mean stone size 12 x 9 mm) were treated on a piezoelectric (EDAP LT-01) lithotripter (mean shock wave number 3420), and ten patients (mean stone size 24 x 17 mm) were treated by PCNL (32F Amplatz sheath in a lower calix). There were no complications, and the stone-free rate at day 30 was 50% in both groups. In the ESWL group, all of the kidneys demonstrated a loss of local uptake, whereas 7 of the 10 in the PCNL group did so. In the ESWL group, 4 of the 12 kidneys had a local loss exceeding 4% but only 2 of 10 kidneys in the PCNL group. There were 7 scars in the treated area in the ESWL group and 6 in the PCNL group. Extracorporeal lithotripsy does not seem to be a nontraumatic procedure for the kidney. For stones that would require several sessions of ESWL, the use of PCNL must be preferred.

Extracorporeal Shock Wave Lithotripsy for Lower Caliceal Calculi

“…Although with increasing ESWL sessions stone clearance is enhanced, the morphologic and functional alterations, which are thought to be transient, might become more evident. It was shown that all patients treated with ESWL had a loss of local dimercaptosuccinic acid uptake in the treated area [20]. Furthermore, the mean loss of local dimercaptosuccinic acid uptake after ESWL was higher than after PCNL.…”

Renal Trauma and the Risk of Long-Term Complications in Shock Wave Lithotripsy

“…Lechevallier et al [36] imaged the treated kidney by single-photon emission computer tomography before SWL and at 30 days after treatment and noted regions of scar formation in 7 of 12 patients. Umekawa et al [37] described the development of anti-glomerular basement membrane antibody-mediated glomerulonephritis that progressed to acute renal failure 90 days after SWL.…”

Usefulness of clearance parametric images in detection of regional renal parenchyma dysfunction

“…Lechevaillier et al [18] applied a static renal study ( 99m Tc-DMSA SPECT) for the evaluation of 12 kidneys before and 30 days after ESWL. They revealed minor tracer uptake defects around foci of post ultrasound shock wave sites.…”