The clinical research of 1,470 nm laser in percutaneous nephrolithotomy

Percutaneous laser nephrolithotripsy: is it here to stay? Results of a systematic review

PURPOSE OF REVIEW

PCNL (percutaneous nephrolithotomy) and its miniaturized variants are being widely employed in stone surgery, owing to their high-stone-free rates (SFRs) and efficacy for large (>20 mm) stones. With advances in laser technology, it has been readily utilized in PCNL, with the potential for lower complication rates at similar SFR. We aimed to perform a systematic literature review with a focus on recent prospective clinical data that compares laser PCNL to either nonlaser PCNL, different PCNL sizes or other current standards of care such as shockwave lithotripsy (ESWL) or flexible ureteroscopy (FURS).

RECENT FINDINGS

Of the 294 studies initially identified through database searching, nine papers published between 2019 and 2021 were included which compared laser PCNL (Standard PCNL in three, mini-PCNL in four, ultra-mini PCNL in one, micro-PCNL in one study) to other nonlaser lithotripsy, ESWL, FURS, and different PCNL sizes. Complications for laser PCNL ranged from bleeding (4.4%), perirenal haematoma (1.1%), fever (4.6%), ureteric/renal pelvic injury (2.3%), haematuria (2.7%), and infection (2.6%). The mean SFR for laser PCNL was 91.5% at 3 months.

SUMMARY

Percutaneous laser nephrolithotripsy is well tolerated and effective, with high-SFRs at 3 months and relatively low intraoperative and postoperative complication rates. Further research is required to assess the role of intraoperative techniques and suction to improve outcomes further.

A retrospective analysis on the effect of single-channel minimally invasive percutaneous nephrolithotomy combined with retrograde flexible ureteroscopy using the completely lateral decubitus and semi-lithotomy positions to treat complex kidney stones

Background

Some types of complex kidney stones cannot be broken down and removed through single-channel percutaneous nephroscope or retrograde flexible ureteroscope. In order to be removed, these types of stones require multiple combined methods to be performed. The aim of this study was to retrospectively evaluate the clinical effect of single-channel minimally invasive percutaneous nephrolithotomy (mPCNL) combined with retrograde flexible ureteroscopy using the completely lateral decubitus and semi-lithotomy positions for treating complex renal calculi.

Methods

We selected 117 patients with complex renal calculi who were admitted to Peking University Shougang Hospital and Weifang People’s Hospital from January 1, 2017, to January 31, 2021. All patients were treated with single-channel mPCNL combined with retrograde flexible ureteroscopy in the completely lateral decubitus and semi-lithotomy positions. During the operation, the patients were placed in a completely lateral decubitus position, or their lower limbs were placed in a semi-lithotomy position for a single attempt only.

Results

An 18-Fr percutaneous channel was successfully established in all patients. The mean operation time was 112±37 minutes, and the average blood loss was 71±31 mL. A 14-Fr renal fistula was maintained for 7 days, a urethral catheter for 2–3 days, and a ureteral stent tube for 2 weeks after each surgery. According to the results of computed tomography (CT) scans performed 3–5 days after the operation, the total lithotripsy success rate reached 100%, with a first-stage lithotripsy rate of 98.29%. Two patients were found to each have 1 residual stone, with a diameter of 4 mm, left in kidney by CT, which then was to be removed under local anesthesia. The average postoperative hospitalized time was 7±2 days, and no severe complications occurred perioperatively.

Conclusions

Single-channel mPCNL combined with retrograde flexible ureteroscopy in the completely lateral decubitus and semi-lithotomy positions is a safe, feasible, and highly effective method of treating complex renal calculi, which is of benefit to save operation time and facilitate operation process, because patient’s position could not need to be changed repeatedly during the surgery.

The impact of lasers in percutaneous nephrolithotomy outcomes: results from a systematic review and meta-analysis of randomized comparative trials

Background Percutaneous nephrolithotomy (PCNL) is the first choice treatment of renal stones larger than 2 cm. We aimed to evaluate if lasers perform as equal as non-laser devices in patients with kidney stones candidate to PCNL. Materials and methods A comprehensive literature search was performed in MEDLINE via PubMed, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) to assess the differences in the perioperative course, incidence of postoperative complications, and stone free-rate (SFR) in patients with kidney stones undergoing laser versus non-laser PCNL in randomized studies. The incidences of complications were pooled using the Cochran-Mantel-Haenszel Method with the random effect model and expressed as Risk Ratios (RR), 95% Confidence Intervals (CI), and p-values. Surgical time and length of stay were pooled using the inverse variance of the mean difference (MD) with a random effect, 95% CI, and p-values. Analyses were two-tailed, with a significance set at p ≤0.05. Results Six papers including 732 patients (311 patients undergoing holmium laser and 421 non-laser PCNL) were included in meta-analysis. Surgical time and postoperative stay were shorter in the non-laser group (MD:11.14, 95% CI:2.32-19.96, p=0.002; MD:-0.81, 95%CI:-2.18-0.57 p=0.25, respectively). SFR was significantly higher in the non-laser group (RR:1.08, 95% CI:1.01-1.15, p=0.03). Patients undergoing laser PCNL had a non-significant higher risk of postoperative fever >38°C (RR:0.64, 95%CI: .31-1.30, p=0.22). Transfusion rate did not differ between the two groups (RR:1.02, 95% CI:0.50-2.11 p=0.95). The need for stent positioning due to urine extravasation was higher risk in the laser group but the difference did not reach significance (RR:0.49, 95% CI:0.17-1.41 p=0.19). Conclusions Non-laser PCNL showed better perioperative outcomes and SFR as compared to holmium laser PCNL.