Presented by: Rabea Moed MD
Soroka University Medical Center

Introduction

Percutaneous Nephrolithotomy (PCNL) is the Gold Standard treatment for large renal stones. During the last few years, miniaturized PCNL has gained popularity, being Holmium Laser (HL) most used for stone treatment, while small-bore ballistic and ultrasonic lithotripters are thought to be less effective. Still, it is unclear which method is more effective for lithotripsy and if stone composition can affect the choice of one modality over the other. We thought of conducting a comparative study that may aid in optimizing lithotripsy modality choice according to the expected stone composition.

Materials

This retrospective study included charts review of patients aged 18 years and above who underwent mini-PCNL for removal of kidney stones using either 100-w HL or 1.83 mm Shockpulse SE (SP) (Olympus®) between 01/01/2019 and 08/01/2021. Patients with renal anatomical variations, those who underwent surgery using both the SP and the HL methods during the same procedure, and patients under the age of 18 were excluded. Statistical analyses were performed, including the χ^2 test, Fisher-Exact test, Mann-Whitney non-parametric test, and logistic regression.

Results

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This study involved 74 participants, 29 in the SP group and 45 in the HL group. There was no significant differences in baseline and demographic data between the groups, including stone burden, staghorn and stone density measured by Hounsfield Units (HU). The SP group had a significantly higher stone-free rate (96.6% vs. 75%, p = 0.034) and less stone residue on average (0.27 vs. 0.86) (p = 0.051) than the HL group. The SP group also had a lower percentage of basket usage compared to the HL group (64.3% vs. 84.4%) (p = 0.048). No significant difference was observed in terms of duration of surgery, length of hospitalization, hemoglobin drop, need for blood products or complications. Stones exhibiting HU values below 1000 displayed a 9.6-fold higher likelihood of achieving stone-free status in the Shockpulse group compared to the Holmium laser group (OR: 1.002, 95% CI: 1.002-91.964, p = 0.05). Conversely, no significant disparity was observed between the two treatments for stones with HU per-CT values above 1000.

Conclusion

According to our study, the mini-SP was shown to be more effective than Holmium laser in achieving stone-free status and reducing the need for basket usage during urinary stone removal in mini-PCNL, especially for non-calcium stones with Hounsfield units below 1000.  Further research is necessary to fully determine the effectiveness of these modalities in mini-PCNL.

Funding

none

Lead Authors

Jonathatn Wagmaister, MD
Soroka University Medical Center

Co-Authors

Nicola Mabjeesh, MD, PHD
Soroka University Medical Center

Muhammad Jabareen, MD
Soroka University Medical Center

Rabea Moed, MD
Soroka University Medical Center

Basel Abu ganem, MD MPH
Soroka University Medical Center

Aviad Korman, Medical Student
Soroka University Medical Center