"VirtualBasket" ureteroscopic holmium laser lithotripsy: intraoperative and early postoperative outcomes

Comparison of the effects of Ho: YAG laser virtual Basket™ pulse modulation and Thulium fiber laser on kidney tissue - an ex vivo experimental study

Through an ex vivo experimental study, we aimed to compare the effects of the Ho: YAG laser Virtual Basket (VB™) modulation and a Thulium fiber laser (TFL) on kidney tissue in different environments and using laser configurations. The 100 W Ho: YAG (Cyber Ho, Quanta System, Italy) and 60 W TFL (Fiber Dust, Quanta System, Italy) laser devices were used. The following laser settings were selected: power in the range of 10-60 W, frequency of 20-40 Hz, and energy of 0.5-1-1.5 J. A medium pulse duration of 600 µsec was used for VB™, while short (spdTFL; 50 µsec) and long (lpdTFL; 15,000 µsec) were used for TFL. The tissue's incision depth (ID), vaporization area (VA), coagulation area (CA), total laser area (TLA = VA + CA), surface section (SS), and lateral effect (LE) were measured. In total, 108 experiments were conducted. No statistically significant difference in mean VA, TLA, ID, LE, or SS was observed between VB™, spdTFL, and lpdTFL in the low-power output group in saline (p > 0.05). However, the mean CA was statistically significantly higher for VB™ (p = 0.005). In saline and high-power output group, the mean VA, CA, TLA, LE, and ID were higher when using lpdTFL than other pulse durations (p = 0.001, p = 0.001, p = 0.001, p = 0.006, and p = 0.001, respectively). Similar to lpdTFL, VB™ may provide controlled dissection and incision as well as haemostasis. At different laser settings, the individual effects of laser properties (such as pulse length, energy and frequency) on tissue may be more significant.

Application of AI in urolithiasis risk of infection: a scoping review

INTRODUCTION

Artificial intelligence and machine learning are the new frontier in urology; they can assist the diagnostic work-up and in prognostication bring superior to the existing nomograms. Infectious events and in particular the septic risk, are one of the most common and in some cases life threatening complication in patients with urolithiasis. We performed a scoping review to provide an overview of the current application of AI in prediction the infectious complications in patients affected by urolithiasis.

EVIDENCE ACQUISITION

A systematic scoping review of the literature was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses for Scoping Reviews (PRISMA-ScR) guidelines by screening Medline, PubMed, and Embase to detect pertinent studies.

EVIDENCE SYNTHESIS

A total of 467 articles were found, of which nine met the inclusion criteria and were considered. All studies are retrospective and published between 2021 and 2023. Only two studies performed an external validation of the described models. The main event considered is urosepsis in four articles, urinary tract infection in two articles and diagnosis of infection stones in three articles. Different AI models were trained, each of which exploited several types and numbers of variables. All studies reveal good performance. Random forest and artificial neural networks seem to have higher AUC, specificity and sensibility and perform better than the traditional statistical analysis.

CONCLUSIONS

Further prospective and multi-institutional studies with external validation are needed to better clarify which variables and AI models should be integrated in our clinical practice to predict infectious events.

A comparison between vapor tunnel and virtual basket for the treatment of proximal ureteral stones using holmium:YAG laser (Cyber Ho): which is the best tool to reduce retropulsion?

PURPOSE

To compare vapor tunnel (VT) and virtual basket (VB) tools to reduce retropulsion in the treatment of proximal ureteral stones.

METHODS

Patients with a single proximal ureteral stone were randomly assigned to holmium laser lithotripsy with the use of VT (Group A) or VB (Group B) tool. The 150W holmium:YAG cyber Ho generator was used. We compared operative time, dusting time, need for flexible ureteroscopy due to stone push-up and occurrence of ureteral lesions. The stone-free rate (SFR) and the occurrence of postoperative ureteral strictures were assessed.

RESULTS

186 patients were treated, of which 92 with the VT (49.5%, Group A) and 94 with the VB (50.5%, Group B). Mean stone size was 0.92 vs. 0.91 cm in Groups A vs. B (p = 0.32). Mean total operative time and dusting time were comparable between groups. 7 (7.6%) vs. 6 (6.4%) patients in Groups A vs. B required a flexible ureteroscope because of stone push-up (p = 0.12). Ureteral mucosa lesions were observed in 15 (16.3%) vs. 18 (19.1%) cases in the VT vs. VB group (p = 0.09). 1-Month SFR was comparable (97.8% vs. 95.7%, p = 0.41). We observed one case (1.1%) of postoperative ureteral stricture in the VT group vs. two cases (2.1%) in the VB group (p = 0.19).

CONCLUSIONS

VT and VB are equally safe and effective tools in reducing retropulsion of ureteral stones. Operative time, dusting time and SFR were comparable. They also equally avoided stone push-up and prevented ureteral lesions, which may later occur in ureteral strictures.

Advances in lasers for the minimally invasive treatment of upper and lower urinary tract conditions: a systematic review

PURPOSE

Technological advancements in laser lithotripsy are expanding into numerous fields of urology, like ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), and benign and malignant soft-tissue treatments. Since the amount of research regarding lasers in urology has grown exponentially, we present a systematic review of the most recent and relevant advances encompassing all lasers used in urological endoscopic treatment.

METHODS

We performed a literature search using PubMed (May 2023) to obtain information about lasers for urological purposes. We included only recent data from published articles between 2021 and 2023 or articles ahead of print.

RESULTS

Lasers are widely used in lithotripsy for ureteric, renal, and bladder stones, benign prostate surgery, and bladder and upper tract tumor ablation. While the holmium (Ho:YAG) laser is still predominant, there seems to be more emphasis on pulse modulation and newer lasers such as thulium fiber laser (TFL) and pulsed Tm:YAG laser.

CONCLUSION

The use of lasers and related technological innovations have shown increasing versatility, and over time have proven to be invaluable in the management of stone lithotripsy, treatment of benign and malignant prostate diseases, and urothelial tumors. Laser endoscopic treatment is heavily based on technological nuances, and it is essential to know at least the basics of these technologies. Ultimately the choice of laser used depends on its availability, cost, surgeon experience and expertise.

Initial experience with robot-assisted ureteroscopy with Ily® Robot

The aim of this study is to present the first Italian experience with robotic-assisted retrograde intrarenal surgery (rRIRS) using the Ily® platform. Procedures were performed for renal stones using the Ily® Robot (STERLAB, Vallauris, France), which is a ureteroscope holder with multiple degrees of freedom that can be controlled remotely through a wireless controller. In March 2023, consecutive patients with indications for rRIRS were included in the study. Demographic variables and stone characteristics were collected, and standard perioperative data were assessed. The one-month stone-free rate (SFR, i.e. no residual fragments) was evaluated using ultrasound. All participating surgeons filled out a Surgeons' Satisfaction Questionnaire (SSQ) based on a Likert-type scale. The questionnaire focused on: 1) ease of use; 2) ergonomics during renal cavity exploration; 3) stability during stone fragmentation. Among the patients, one had bilateral stones, while two had stones on the right side. The mean stone size was 13 mm. The average operative time was 70 minutes and the mean docking time was three minutes. No perioperative complications were recorded, and all patients were discharged on the first postoperative day. The one-month SFR was 100%. The SSQ scores were as follows: 1) ease of use: 4/5; 2) ergonomics: 5/5; 3) stability during stone fragmentation: 5/5. Based on the initial experience, the results indicate the feasibility, safety, and effectiveness of rRIRS. The ergonomic efficiency of the system was highly appreciated by the surgeons. While a cost-effectiveness analysis within clinical trials is necessary, rRIRS shows the potential for a more sustainable future for endoscopists and an improved workplace environment.

Effect of Ho:YAG laser on kidney tissue with Virtual Basket™ and Bubble Blast™ pulse modulation: an experimental ex vivo study

PURPOSE

There is a lack of studies in the literature on effects of Virtual Basket™ (VB) and Bubble Blast™ (BB) laser pulse modulations of the Ho:YAG laser on tissue. We aimed to compare the effects of standard modulation (SM), VB, and BB pulse modulations of Ho:YAG laser on kidney tissue.

METHODS

An ex vivo experiment was conducted using veal kidneys. The Quanta System Cyber Ho 100W laser generator with a broad setting spectrum at 15-80 W, 10-40 Hz, 1.5-2 J, and medium pulse duration were tested. Incision depth (ID), vaporization area (VA), coagulation area (CA), and total laser area (TLA = VA + CA) were evaluated. Histopathological measurement outcomes were grouped as a low-power group (15, 20, and 30 W) and a high-power group (40, 60, and 80 W) according to the power outputs used.

RESULTS

A total of 108 experiments were performed. In saline and high-power output (40, 60, 80 W), mean VA, TLA, and ID, histopathological measurements were higher in BB pulse modulation than VB and SM pulse modulations (p: 0.03, p: 0.001, and p: 0.003, respectively). In contrast, mean CA and LE measurements were higher in SM than in VB and BB pulse modulations (p < 0.001 and p < 0.001, respectively). There was no statistically significant difference in mean histopathological measurements of VA, CA, TLA, and ID, among SM, VB, and BB pulse modulations in the low-power output group in saline (p > 0.05).

CONCLUSION

VB can allow controlled dissection, as it does not create a large VA during surgical procedures. BB should be used in a controlled manner in soft tissue surgery due to its strong effect on tissues.

Lasers for stone lithotripsy: advantages/disadvantages of each laser source

PURPOSE

The purpose of this article was to make a narrative review of the literature in search of all articles regarding thulium:yttrium-aluminium-garnet (YAG), thulium laser fiber (TFL) and holmium:YAG (Ho:YAG) for lithotripsy from 2020 to 2023. A selection of articles of special interest and best evidence was made in order to give a better perspective on their advantages and disadvantages.

RECENT FINDINGS

New Ho:YAG technologies of as high power, high frequency and pulsed modulations have shown promising results for lithotripsy by reducing retropulsion with good ablation efficiency. High peak power makes it particularly good for percutaneous nephrolithotomy. High intrarenal temperatures and correct setting are still concerning points.TFL has arrived to be one of the main players in flexible ureteroscopy. Being highly efficient and quick, and by producing micro-dusting the laser is quickly heading to become a gold standard. The new pulsed Thulium YAG is the newest laser. For now, only in-vitro studies show promising results with efficient lithotripsy. As the peak power lies between Ho:YAG and TFL it may be able to adequately perform when needing and low power lithotripsy.

SUMMARY

Several new technologies have been developed in the last years for stone lithotripsy. All being efficient and safe if well used. Different advantages and disadvantages of each laser must be taken into consideration to give each laser the proper indication.

Innovations in Kidney Stone Removal

Urolithiasis is a common clinical condition, and surgical treatment is performed with different minimally invasive procedures, such as ureteroscopy, shockwave lithotripsy and percutaneous nephrolithotomy. Although the transition from open surgery to endourological procedures to treat this condition has been a paradigm shift, ongoing technological advancements have permitted further improvement of clinical outcomes with the development of modern equipment. Such innovations in kidney stone removal are new lasers, modern ureteroscopes, development of applications and training systems utilizing three-dimensional models, artificial intelligence and virtual reality, implementation of robotic systems, sheaths connected to vacuum devices and new types of lithotripters. Innovations in kidney stone removal have led to an exciting new era of endourological options for patients and clinicians alike.

Comparison of stone retropulsion between Moses mode and virtual basket mode: an in vitro study using artificial stones

This study aimed to evaluate stone retropulsion in various laser pulse modes in both Moses mode (MM) and virtual basket mode (VBM). Experiments were performed using a channel-shaped rubber rail and artificial stones. We compared short pulse mode and long pulse mode in both MM and VBM with the laser tip positioned so that it was touching and at 1 and 2 mm distances from the stone surface. Stone retropulsion was measured after the laser fired for 10 s in three different laser settings: 0.5 J/8 Hz, 0.8 J/8 Hz and 1.0 J/8 Hz. When the laser tip was touching the artificial stone, stone retropulsion in MM was significantly shorter than that in VBM in all laser settings (P < 0.01, P = 0.02 and P = 0.02, respectively). At 1-mm distance, stone retropulsion in MM was significantly shorter than that in VBM in 0.8 J/8 Hz and 1.0 J/8 Hz settings (P < 0.01 and P = 0.01, respectively). At 2-mm distance, however, there were no differences between MM and VBM in stone retropulsion in any laser settings. Stone retropulsion was not significantly different between the laser settings at 1-mm distance in MM, or when touching in VBM. In conclusion, stone retropulsion distance in MM can be shorter than that in VBM. Stone retropulsion in MM and VBM may be differently influenced by laser settings and laser tip position.

New Generation Pulse Modulation in Holmium:YAG Lasers: A Systematic Review of the Literature and Meta-Analysis

(1) Background: New pulse modulation (PM) technologies in Holmium:YAG lasers are available for urinary stone treatment, but little is known about them. We aim to systematically evaluate the published evidence in terms of their lithotripsy performance. (2) Methods: A systematic electronic search was performed (MEDLINE, Scopus, and Cochrane databases). We included all relevant publications, including randomized controlled trials, non-randomized comparative and non-comparative studies, and in-vitro studies investigating Holmium:YAG lithotripsy performance employing any new PM. (3) Results: Initial search yielded 203 studies; 24 studies were included after selection: 15 in-vitro, 9 in-vivo. 10 In-vitro compared Moses with regular PM, 1 compared Quanta’s, 1 Dornier MedTech’s, 2 Moses with super Thulium Fiber Laser, and 1 compared Moses with Quanta PMs. Six out of seven comparative studies found a statistically significant difference in favor of new-generation PM technologies in terms of operative time and five out of six in fragmentation time; two studies evaluated retropulsion, both in favor of new-generation PM. There were no statistically significant differences regarding stone-free rate, lasing and operative time, and complications between Moses and regular PM when data were meta-analyzed. (4) Conclusions: Moses PM seems to have better lithotripsy performance than regular modes in in-vitro studies, but there are still some doubts about its in-vivo results. Little is known about the other PMs. Although some results favor Quanta PMs, further studies are needed.

Stone ablation rates using innovative pulse modulation technology: Vapor tunnel, virtual basket, and bubble blast. An in vitro experimental study

INTRODUCTION AND OBJECTIVES

Virtual Basket^TM , Bubble Blast^TM , and Vapor Tunnel^TM are three laser pulse modulation technologies that modify the holmium: yttrium-aluminum-garnet (Ho:YAG) laser pulse transmission through the creation of bubbles emerging from the fiber tip with different effects on the target stone. The primary outcome of the current study was to test the stone ablation rates for the different pulse modulation modes, Virtual Basket, Bubble Blast, and Vapor Tunnel, using different power, energy, and frequency settings.

MATERIALS AND METHODS

Quanta Cyber: Ho 150 W^TM , a 365 µm Precision^TM fiber, and hard and soft phantom BegoStones^TM were used in an in vitro experimental configuration in a saline bath. In the Virtual Basket mode, the combinations of power, energy and frequency were tested; 10 W = 0.5 J × 20 Hz, 10 W = 0.5 J × 20 Hz, 60 W = 1 J × 60 Hz and 60 W = 2 J × 30 Hz. In the Bubble Blast mode, the combinations, 12 W = 1.2J × 10 Hz, 60 W = 1.2J × 50 Hz and 60 W = 2 J × 30 Hz, were tested. Similarly, the combination of 10 W = 0.5 J × 20 Hz was tested with Vapor Tunnel mode. High-speed camera captures of the bubble formation and regular photographs of the fragmentation pattern were also taken for each mode.

RESULTS

High power lithotripsy was faster and related to higher ablation rates. The Virtual Basket, Bubble Blast, and Vapor Tunnel modalities showed different ablation rates for the same energy and frequency settings. For hard stones, there was an improvement in the ablation rate using 60 W = 2 J × 30 Hz compared with 60 W = 1 J × 60 Hz and 60 W = 1.2 J × 50 Hz. The highest ablation rates were recorded using the Virtual Basket mode with the high-power settings of 2 J of energy and 30 Hz of frequency.

CONCLUSIONS

The Virtual Basket^TM pulse-modulation technology was related to the highest ablation rates for both hard and soft stones, compared to the Bubble Blast^TM and the Vapor Tunnel^TM technologies in high-power and low-power lithotripsy respectively. For the same high power settings, higher energy seems to provide higher ablation rates.