Thulium fiber laser: The new kid on the block

Safety and Efficacy of "Dusting and Pop-Dusting" with High-Power Laser for Treatment of Large Pediatric Stones with Ureteroscopy and Lasertripsy: Prospective Outcomes from a University Teaching Hospital

Introduction: The wide use of high-power laser has changed the landscape of ureteroscopy and lasertripsy (URSL). We wanted to look at the role and outcomes of high-power holmium:yttrium-aluminum-garnet laser for URSL in pediatric stone disease. Methods: A prospective analysis of consecutive pediatric patients treated with "Dusting and Pop-dusting" using a high-power laser was done between January 2016 and March 2022. The project was registered with our audit committee. Data were analyzed for patient demographics, stone characteristics, operative details, procedural outcomes, and complications. Stone-free rate (SFR) was defined as fragments ≤2 mm on postoperative ultrasound imaging 2-3 months after the procedure. Results: A total of 35 patients underwent 43 procedures (1.2 procedure/patient) during the study period with a mean age of 9.4 years (range 1-16 years) and a male:female ratio of 13:22. The stone location was in the kidney in 32 (91.4%) patients of which 8 were in multiple renal locations. The mean stone size was 18 mm (range 10-39 mm), with the pre- and post-stent rates of 37% and 56%, respectively. An access sheath was used in 19 (44%) procedures. The overall SFR on ultrasound scan was 94% (n = 33) with no procedural complications noted in our series and a mean length of stay of 0.9 days. Conclusion: Pediatric URSL using a high-power laser achieves a high SFR even for large and multiple renal stones with no complications noted in our prospective series. Parents must, however, be counseled about the need for staged procedures, which might be needed for large stones.

Laser Technology Advancements in the Treatment of Benign Prostatic Hypertrophy

PURPOSE OF REVIEW

Lasers have had a significant impact on the treatment of benign prostatic hypertrophy. This article attempts to distill the advancements in laser technology for the treatment of benign prostatic hypertrophy (BPH) into key and understandable points to help make this topic more accessible to urologists.

RECENT FINDINGS

The holmium:yttrium-aluminum-garnet (YAG) laser, one of the most significant lasers in the field of urology, has recently been improved with pulse modulating technology (Moses™ technology). New thulium:YAG technology allows both pulsed and continuous wave modes. The thulium fiber laser is one of the newer lasers to come to market and has been shown to have effective and safe outcomes. GreenLight™ lasers are predominantly used in photovaporization procedures and have also been studied extensively, although less in recent years. The modern urologist is fortunate to have many high-quality lasers and a wide variety of surgical techniques to choose from when treating BPH. Understanding the basic laser principles and applications will help urologists to select the best treatment options for their patients with BPH.

Endoscopic enucleation of the prostate with Thulium Fiber Laser (ThuFLEP). A retrospective single-center study

PURPOSE

The aim of the present, retrospective study was to describe our initial experience and early outcomes of Thulium Fiber Laser enucleation of the prostate (ThuFLEP) with the use of the FiberDust™ (Quanta System, Samarate, Italy) in patients with benign prostate hyperplasia.

METHODS

From June 2022 to April 2023, all patients who underwent endoscopic enucleation of the prostate at Urology Department of the University Hospital of Patras were included. A single surgeon utilizing the same standardized operative technique performed all the surgeries. The primary endpoints included the uneventful completion of the operation, the surgical time and any minor or major complication observed intra- or post-operatively.

RESULTS

Twenty patients with benign prostate hyperplasia were treated with ThuFLEP. All the surgeries were completed successfully and uneventfully. The enucleation phase of the operation was completed in a mean time of 45±9.1 min, while the average time needed for the morcellation was 17.65±3.42 min. No significant complications were observed intra- or post-operatively. The average hemoglobin drop was calculated to be 0.94±0.71 g/dL.

CONCLUSIONS

All the operations were successfully and efficiently completed with the use of the FiberDust™ (Quanta System, Samarate, Italy) in ThuFLEP. Significant blood loss or major complications were not observed.

Do Hounsfield Units have any significance in predicting intra- and postoperative outcomes in retrograde intrarenal surgery using Holmium and Thulium fiber laser? Results from the FLEXible ureteroscopy Outcomes Registry (FLEXOR)

PURPOSE

To evaluate outcomes of flexible ureteroscopy for renal stones by comparing hard versus soft stones based on their attenuation on computed tomography (Hounsfield Units-HU).

METHODS

Patients were divided into two groups according to the type of laser employed [Holmium:YAG (HL) or Thulium fiber laser (TFL)]. Residual fragments (RF) were defined as > 2 mm. Multivariable logistic regression analysis was performed to evaluate factors associated with RF and RF needing further intervention.

RESULTS

4208 patients from 20 centers were included. In whole series, age, recurrent stones, stone size, lower pole stones (LPS), and multiple stones were predictors of RF at multivariable analysis and LPS and stone size with RF requiring further treatment. HU and TFL were associated with lesser RF and RF requiring an additional treatment. In HU < 1000 stones, recurrent stones, stone size, and LPS were predictors of RF at multivariable analysis, whereas TFL was less likely associated with RF. Recurrent stones, stone size, and multiple stones were predictors of RF requiring further treatment, while LPS and TFL were associated with lesser RF requiring further treatment. In HU ≥ 1000 stones, age, stone size, multiple stones, and LPS were predictors of RF at multivariable analysis, while TFL was less likely associated with RF. Stone size and LPS were predictors of RF requiring further treatment, whereas TFL was associated with RF requiring further treatment.

CONCLUSION

Stone size, LPS, and use of HL are predictors of RF after RIRS for intrarenal stones regardless of stone density. HU should be considered an important parameter in predicting SFR.

Pulsed-wave vs Continuous-wave Thulium Fiber Laser Enucleation of the Prostate (ThuFLEP): A Comparison of Perioperative Outcomes

OBJECTIVE

To compare intra and early postoperative outcomes between pulsed-wave and continuous-wave Thulium Fiber Laser Enucleation of the Prostate (PW-ThuFLEP vs CW-ThuFLEP) for the treatment of benign prostatic hyperplasia.

METHODS

238 patients with lower urinary tract symptoms due to benign prostatic hyperplasia underwent PW-ThuFLEP (118 patients) vs CW-ThuFLEP (120 patients). Preoperative prostate volume, adenoma volume, prostate-specific antigen (PSA), and hemoglobin values were recorded. International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), post-void residual volume, and International Index of Erectile Function-5 score (IIEF-5) were assessed. Operative time, enucleation time, enucleation efficiency, catheterization time, irrigation volume, hospital stay, hemoglobin drop, and postoperative complications were recorded. Micturition improvements and sexual outcomes were evaluated 3months after surgery.

RESULTS

CW-ThuFLEP showed shorter operative time (61.5 vs 67.4 minutes, P = .04). Enucleation time (50.2 vs 53.3 minutes, P = .12), enucleation efficiency (0.8 vs 0.7 g/min, P = .38), catheterization time (2.2 vs 2.1days, P = .29), irrigation volume (32.9 vs 32.8L, P = .71), hospital stay (2.8 vs 2.6days, P = .29) and hemoglobin drop (0.38 vs 0.39 g/dL, P = .53) were comparable. No significant difference in complication rate was observed. At 3-month follow-up, the procedures did not show any significant difference in IPSS, Qmax, post-void residual volume, IIEF-5, and PSA value.

CONCLUSION

PW-ThuFLEP and CW-ThuFLEP both relieve lower urinary tract symptoms equally, with high efficacy and safety. Operative time was significantly shorter with CW-ThuFLEP, but with a small difference with low clinical impact. Enucleation time, enucleation efficiency, catheterization time, irrigation volume, hospital stay, hemoglobin and PSA drop, complication rate, and sexual outcomes showed no differences.

Ureteroscopy and lasertripsy with pop dusting using high power holmium laser for large urinary stones > 15 mm: 6.5-year prospective outcomes from a high-volume stone center

INTRODUCTION

Ureteroscopy and stone lasertripsy (URSL) is a recognized technique for treatment of urinary tract stones. Holmium:Yag laser has been successfully used for this purpose for the last two decades. More lately, pulse modulation with Moses technology and high power lasers have been introduced with the result of faster and more efficient stone lasertripsy. Pop dusting is a two-stage combined treatment using a long pulse Ho:YAG laser, initially in contact mode with the stone 'dusting' (0.2-0.5 J/40-50 Hz) followed by non-contact mode 'pop-dusting' (0.5-0.7 J/20-50 Hz). We wanted to look at the outcomes of lasertripsy for renal and ureteric stones using a high-power laser machine.

METHODS

Over a period of 6.5 years (January 2016-May 2022), we prospectively collected data for patients undergoing URSL for stones larger than 15 mm treated using high power Ho:YAG laser (60W Moses or 100W laser). Patient parameters, stone demographics and outcomes of URSL were analyzed.

RESULTS

A total of 201 patients, underwent URSL for large urinary stones. In 136 patients (61.6%) stones were multiple and the mean single and cumulative stone size was 18 mm and 22.4 mm respectively. A pre- and post-operative stent was placed in 92 (41.4%) and 169 (76%) respectively. The initial and final stone free rate (SFR) were 84.5% and 94% respectively and 10% patients underwent additional procedure to achieve stone free status. 7 (3.9%) complications were recorded, all related to UTI/sepsis, with 6 Clavien II and 1 Clavien IVa complication.

CONCLUSION

Dusting and pop-dusting has shown to be successful and safe with the ability to treat large, bilateral or multiple stones with low retreatment and complication rates.

Cystine Stones: Developments in Minimally Invasive Surgery and Their Impact on Morbidity and Stone Clearance

Cystinuria is a rare genetic condition that is responsible for cystine stones. Besides stone recurrence, patients with cystine stones have reduced health-related quality of life, increased rates of chronic kidney disease and hypertension. Although lifestyle measures, medical therapy and close follow up are essential to reduce and monitor cystine stone recurrences, surgical intervention is frequently needed for most cystinuria patients. Shock wave lithotripsy, ureteroscopy, percutaneous nephrolithotomy and active surveillance all have a role, and technological advances in endourology are vital in achieving a stone-free status and to prevent recurrences. The complexity of managing cystine stones necessitates a multidisciplinary team discussion, patient involvement and an individualised approach in a specialist centre for optimum management. Thulium fibre laser and virtual reality may have an increasing role in the future of cystine stone management.

Incidence of Ureteric strictures Following Ureteroscopic Laser Lithotripsy: Holmium:YAG Versus Thulium Fiber Laser

OBJECTIVE

We aimed to compare the incidence of ureteric strictures between holmium:yttrium aluminum garnet and thulium fiber laser following ureteroscopic laser lithotripsy. In the present era of miniaturization of endourologic armamentarium and better optics, how safe are lasers to fire inside ureter?

MATERIALS AND METHODS

It is a prospective comparative study over a period of 2 years that included patients who underwent ureteroscopic laser lithotripsy for ureteric stones. Patients were randomly divided into 2 groups: group A underwent holmium:yttrium aluminum garnet laser lithotripsy and group B underwent thulium fiber laser lithotripsy.

RESULTS

A total of 478 patients were analyzed after excluding patients not willing to participate and patients lost to follow-up. Two hundred forty patients underwent holmium:yttrium aluminum garnet laser lithotripsy (group A) and 238 patients underwent thulium fiber laser lithotripsy (group B). The demographic data of 2 groups were comparable. The mean age of patients in group A and group B was 36.5 ± 12.52 years and 38.62 ± 10.71 years, respectively. The mean operative time in group A and group B was 47 ± 15 and 36 ± 13 minutes, respectively, while the mean laser time in group A and group B was 13.5 ± 45 minutes and 9.25 ± 3.2 minutes, respectively. Four (1.67%) patients in group A and 11 (4.62%) patients in group B developed ureteric strictures during follow-up, and the difference was statistically significant (P <.001). The mean length of stricture was 2.67 ± 1.27 cm in group A and 4.42 ± 2.2 cm in group B, and the difference was statistically significant.

CONCLUSION

Thulium fiber laser, projected as safe laser previously, has a higher incidence of ureteric strictures compared to holmium:yttrium aluminum garnet laser when used for ureteroscopic laser lithotripsy.

Minimally Invasive Urological Procedures and Related Technological Developments-Series 2

The world of minimally invasive urology has experienced enormous growth in recent decades with technological innovations related to new techniques and equipment, better training, and the clinical adoption of translational research [...].

Thulium: YAG vs continuous-wave thulium fiber laser enucleation of the prostate: do potential advantages of thulium fiber lasers translate into relevant clinical differences?

PURPOSE

To compare endoscopic enucleation of the prostate using a thulium: yttrium-aluminum-garnet (Tm:YAG) laser and a super-pulsed thulium fiber laser set in continuous-wave (CW) mode, and to evaluate whether theoretical advantages of thulium fiber lasers, related to their shorter wavelength, translate into relevant clinical differences.

METHODS

In total, 110 patients suffering from lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia were randomized to undergo either thulium:YAG laser enucleation of the prostate (ThuLEP) or CW thulium fiber laser enucleation of the prostate (CW-ThuFLEP). Intraoperative and postoperative variables and complications were compared. Micturition improvement was assessed at 3-month follow-up using the International Prostate Symptom Score (IPSS), post-void residual urine (PVR) and maximum flow rate (Qmax). Erectile function was evaluated using the International Index of Erectile Function-5 (IIEF-5).

RESULTS

No significant differences between the ThuLEP and CW-ThuFLEP groups were found in terms of operative time (70.69 vs 72.41 min), enucleation time (50.23 vs 53.33 min), enucleated tissue weight (40.2 vs 41.9 g), enucleation efficiency (0.80 vs 0.79 g/min), catheterization time (2.45 vs 2.57 days), hospital stay (2.82 vs 2.95 days) and hemoglobin drop (1.05 vs 1.27 g/dl). At 3-month follow-up, no significant differences were found in IPSS (5.09 vs 5.81), Qmax (26.51 vs 27.13 ml/s), PVR (25.22 vs 23.81 ml) and IIEF-5 (14.01 vs 14.54).

CONCLUSION

ThuLEP and CW-ThuFLEP were equivalent in relieving patients from LUTS and improving micturition. Theoretical advantages of the TFL, such as shallower penetration depth and improved vaporization capacity, did not translate into relevant perioperative outcomes or clinical differences.

A comparison among RIRS and MiniPerc for renal stones between 10 and 20 mm using thulium fiber laser (Fiber Dust): a randomized controlled trial

PURPOSE

We performed a prospective randomized comparison among Retrograde IntraRenal Surgery (RIRS) and MiniPerc (MP) for stones between 10 and 20 mm to evaluate outcomes with the same laser device: Fiber Dust.

METHODS

Patients with a single renal stone between 10 and 20 mm were randomized to RIRS (Group A) versus MP (Group B). Exclusion criteria were age < 18 or > 75, presence of acute infection, coagulation impairments, cardiovascular or pulmonary comorbidities. In both groups, the Fiber Dust laser was used. A CT scan after 3 months was performed. A negative CT scan or asymptomatic patients with stone fragments < 3 mm and a negative urinary culture were the criteria to assess the stone-free status. A statistical analysis was carried out to assess success, complication and retreatment rates and need for auxiliary treatments.

RESULTS

Between January 2021 and January 2022, 186 patients were enrolled (90 in Group A and 96 in Group B). Mean stone size was 15.8 mm and 14.9 mm in Group A and B, respectively (p = 0.23). The overall stone-free rate (SFR) was 73.3% for Group A and 84.4% for Group B. A higher SFR was reached for upper calyceal stones in Group A (90.4%) lower calyceal stones in Group B (91.6%). Retreatment rate (p = 0.31) and auxiliary procedure rate (p = 0.18) were comparable. Complication rate was 5.5% and 5.2% for Groups A and B, respectively.

CONCLUSIONS

RIRS and MP are both effective to obtain a postoperative SFR with Fiber Dust. According to the stone position one treatment is superior to the other one.

Thulium fiber laser's dust for stone composition analysis: Is it enough?

Introduction: We aimed to evaluate if the biochemical composition of urinary stones can be determined by analyzing the stone dust only, and whether a photo taken during the surgery could be useful for completing the morpho-constitutional analysis. Materials and methods: 20 patients went through a retrograde intrarenal surgery (RIRS) for renal stone treatment with TFL (Fiber Dust, Quanta, 2020) using 150 µm silica core laser fibers. After laser lithotripsy, residual fragments (RF) were removed with a basket (ZeroTip, Boston Scientific) and spontaneously floating stones particles were considered stone dust and were aspirated through the working channel. Pairs of RF and stone dust were labelled and sent to analysis by scanning electron microscopy and Fourier transform infrared spectroscopy (FTIR). Photos of the stone (surface and section) were taken from videos recorded during the surgery. Results: A total of 20 patients were included in the study. Mean age was 49,8 years old with metabolic and genetic disorders. Mean stone volume was 750 mm3 for ureteral stones and 2334 mm3 for renal stones. Mean stone density was 1187 HU. Positive urine culture was found in 25% patients. In 2/20 (10%) the biochemistry differed only in the relative proportions of each constituent, whilst 5/20 (25%) only one component was missing. Laser crystalline conversion was found in 3/20 (15%). Whewellite and weddellite layers were found in photos thus adding missing information from dust stone analysis. Conclusion: Analyzing aspirated dust through the ureteroscope's working channel by physical techniques, we can understand the lithogenic process of the urinary stone, without needing to analyze the stone fragment. Morphological analysis, given by a proper stone picture, adds missing information in specific cases.

SIMULTANEOUS BILATERAL ENDOSCOPIC SURGERY (SBES): IS IT READY FOR PRIME TIME?

Introduction To date, some data available in literature on simultaneous bilateral endoscopic surgery (SBES) have shown good outcomes in terms of both effectiveness and safety. The aim of this study was to report the outcomes pertaining to the effectiveness and safety of SBES performed in our series of patients with bilateral renal stones. Materials and Methods A prospective analysis of consecutive patients who underwent SBES for bilateral renal stones at our institution between June 2017 and September 2021 was performed. Routine preoperative and 1-month postoperative work-up included history, physical examination, urinalysis, urine culture, and blood tests, including the evaluation of estimated glomerular filtration rate (eGFR) using the Cockcroft-Gault equation. An abdominal non-contrast computerized tomography (NCCT) scan was performed in all cases preoperatively and 1-month postoperatively. Peri/postoperative complications were reported according to the Clavien-Dindo classification system. The primary endpoint of the study was stone-free rate (SFR), and the secondary endpoints were Clavien-Dindo complications grade 1 or higher. Results Altogether, 101 patients met the inclusion criteria and were enrolled in the study. SFR for all renal units was achieved in 82 patients (81.1%) at the 1-month follow-up. Twelve patients underwent additional flexible ureteroscopy for residual fragments, and seven asymptomatic patients with single small residual fragment were observed. Eighteen patients (17.8%) experienced Clavien-Dindo Grade I-II complications, whereas one patient (1%) experienced Clavien-Dindo Grade IIIa complication (renal arteriovenous fistula embolization under local anesthesia). Conclusions SBES is a safe and effective procedure for the treatment of bilateral renal stones. Further randomized studies with larger populations are needed to confirm these favorable outcomes of SBES to establish it as an alternative to staged surgeries in patients with bilateral renal stones. Appropriate patient selection is of paramount importance for achieving good outcomes without experiencing severe complications.

Thulium fiber laser pre-settings during ureterorenoscopy: Twitter's experts' recommendations

INTRODUCTION

Thulium fiber laser (TFL) is a novel laser in the field of urology. There is no consensus for optimal parameters. As most urologists use social media, being Twitter the platform with the most dissemination in healthcare, we aim to review the preferred TFL settings chosen by the experts and, to evaluate their pros and cons.

MATERIALS AND METHODS

A Twitter review was performed from November 2019 (firsts TFL experiences in urology) until October 2021 using the hashtags: "thuliumfiber", "ThuliumFiberLaser", "TFL" "soltive", "fiberdust", "OlympusUrology", "quanta_system", "IPG_Photonics", "rocamed". Only board-certified urologists were considered. The "tweets" selected include information about TFL preferred settings for stone lithotripsy and tissue ablation. Additionally, we also seek information regarding laser technique, fiber size, laser time, stone type and equipment.

RESULTS

A total of 42 opinions were identified. The 23 endourologists have a median of 2.298 followers (range 202-10.000). Most comments were about TFL settings for kidney stone dusting (61%). There was a significant difference (p < 0.05) for kidney stone dusting settings (dusting, frequency, and power) between endourologists. Only 24% reported their fiber size, 4 reported the stone composition and 2 endourologists mentioned their type of ureteroscope. There was no discussion about technique used (burst or continuous) nor equipment. Surgery time was reported 3 times.

CONCLUSION

There is no consensus in TFL pre-settings. When a pre-setting is proposed, it should also recommend technique to be used. Settings are personal and related to multiple factors, such as training, technique, equipment and fiber size.

Thulium fiber laser versus holmium:yttrium aluminum garnet laser for stone lithotripsy during mini-percutaneous nephrolithotomy: A prospective randomized trial

INTRODUCTION

We aimed to evaluate the effectiveness and safety of the newly launched thulium fiber laser (TFL) with holmium laser lithotripsy in the miniaturized percutaneous nephrolithotomy (Miniperc) procedure for renal stones.

METHODS

The prospective study included patients with renal stones of size >1 cm to ≤3 cm. The patients who opted for extracorporeal shock wave lithotripsy, retrograde intrarenal surgeries, and stones >3 cm were excluded from the study. Demographics such as patient's age, sex, stone volume, and hardness were evaluated. The patients were randomized into holmium and TFL group for stone lithotripsy. Both the procedures were evaluated for stone disintegration time, operative time, hospital stay, intra- and postoperative complications, and stone-free rate.

RESULTS

A total of 125 patients with renal stones who underwent Miniperc were included in this study. The average size of the stone was comparable in both the groups (P = 0.053). The median stone disintegration time with holmium laser was 20 min 45 s and with TFL, it was 11 min 19 s (P < 0.001). The most common complications were Clavien grade I and II complications (P = 0.128). Prolonged postoperative hematuria was observed in the Thulium fiber laser group, which was conservatively managed. The stone-free rate with TFL (94.9%) was better than Holmium lithotripsy (90.9%).

CONCLUSIONS

The TFL has significant less stone disintegration time which effectively reduced the operative time of Miniperc procedure. The stone-free rate is better, but the incidence of self-limiting hematuria is higher with TFL as compared to Holmium laser.

In vitro fragmentation performance of a novel, pulsed Thulium solid-state laser compared to a Thulium fibre laser and standard Ho:YAG laser

The aim of this work was to compare the fragmentation efficiency of a novel, pulsed Thulium solid-state laser (p-Tm:YAG) to that of a chopped Thulium fibre laser (TFL) and a pulsed Holmium solid-state laser (Ho:YAG). During the fragmentation process, we used a silicone mould to fixate the hemispherical stone models under water in a jar filled with room-temperature water. Each laser device registered the total energy applied to the stone model to determine fragmentation efficiency. Our study examined laser settings with single pulse energies ranging from 0.6 to 6 J and pulse frequencies ranging from 5 to 15 Hz. Similar laser settings were applied to explicitly compare the fragmentation efficiency of all three devices. We experimented with additional laser settings to see which of the three devices would perform best. The fragmentation performance of the three laser devices differed statistically significantly (p < 0.05). The average total energy required to fragment the stone model was 345.96 J for Ho:YAG, 372.43 J for p-Tm:YAG and 483.90 J for TFL. To fragment the stone models, both Ho:YAG and p-Tm:YAG needed similar total energy (p = 0.97). TFL’s fragmentation efficiency is significantly lower than that of Ho:YAG and p-Tm:YAG. Furthermore, we found the novel p-Tm:YAG’s fragmentation efficiency to closely resemble that of Ho:YAG. The fragmentation efficiency is thought to be influenced by the pulse duration. TFL’s shortest possible pulse duration was considerably longer than that of Ho:YAG and p-Tm:YAG, resulting in Ho:YAG and p-Tm:YAG exhibiting better fragmenting efficiency.

Role of Ureteroscopy in Treatment of Upper Tract Urothelial Carcinoma

Purpose of Review

Upper tract urothelial carcinoma (UTUC) is uncommon accounting for less than 10% of all urothelial tumours. Ureteroscopic management (URS) is the first line treatment for low-risk disease and has been increasingly utilised due to technological advances and increasing surgical experience. This review looks at patient outcomes relating to URS, emerging technologies and the role of adjuvant intracavitary therapy in the management of UTUC.

Recent Findings

URS has firmly established itself in the management algorithm for UTUC, and a good body of evidence supports its use for low-risk disease, wherein oncological outcomes are comparable to traditional nephroureterectomy (RNU). Larger tumours can now be managed using URS with a lower morbidity than radical surgery, though with higher associated local recurrence rate and risk of progression to RNU, and as a result, patient selection and close surveillance remains key. There is limited evidence for adjuvant intracavitary therapy (Mitomycin C or BCG) in UTUC although the development of novel polymers and biodegradable stents may improve drug delivery to the upper urinary tract.

Summary

URS has a clearly defined role in low-risk UTUC, and its use in larger tumours appears to be appropriate in a selected cohort of patients. The efficacy of adjuvant intracavitary therapy is as of yet undetermined, though developments in delivery techniques are promising. Likewise further developments of laser technology are anticipated to further expand the role of URS.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11934-021-01065-7.

Managing Urolithiasis with Thulium Fiber Laser: Updated Real-Life Results-A Systematic Review

Thirty-three years ago, pulsed lasers marked the beginning of a new era in endoscopic lithotripsy, and the one that was highlighted because of its potential was the Holmium: YAG laser, which became and still is the gold standard in endourology. Recently, a new laser technology has been accepted for clinical use in lithotripsy: the thulium fiber laser (TFL), showing appealing characteristics not seen before in several preclinical studies. A review of the literature was performed and all relevant in vitro studies and clinical trials until April 2021 were selected. The search came back with 27 clinical experiences (7 full-text clinical trials and 20 peer-reviewed abstracts) and 33 laboratory studies (18 full-text articles and 15 peer-reviewed abstracts). The clinical experiences confirmed the clinical safety of using the wide parameter range of the TFL. This technology demonstrated the performance at a higher ablation speed, the higher ablation efficiency, and the better dust quality of the TFL, as well as reduced stone retropulsion, thus helping to maintain an optimal visibility. No thermal or radiation damage was found. Given the current evidence, we may be facing the future gold standard laser in endoscopic lithotripsy.

A Systematic Review of Thulium Fiber Laser: Applications and Advantages of Laser Technology in the Field of Urology

Laser technology is widely used in urological surgery, from lithotripsy, prostate surgery to en-bloc resection of tumours. While Holmium:YAG has been widely employed over the last two decades, in recent years, there has been a surge of interest in Thulium Fiber Laser (TFL), which offers theoretical advantages of better water absorption and lower stone ablation thresholds. A systematic review was conducted to assess the evidence from clinical research on TFL's application for lithotripsy and prostate surgery. It identified 357 articles and 8 (1506 patients) were selected, of which 4 clinical studies each investigated TFL enucleation of prostate (ThuFLEP) and TFL lithotripsy. For flexible ureteroscopic lithotripsy (FURSL), stone ablation settings ranged from 0.1-4 J, and 7-300 Hz, mean operative time ranged from 23.4-39.8 minutes and lasing time ranged from 1.2-10 minutes. For stone dusting in percutaneous nephrolithotomy (PCNL), settings of 0.2 J and 125-200 Hz were found to be optimal. For ThuFLEP, all studies showed a significant improvement in IPSS (International Prostate Symptom Score), urinary flow rate (Qmax), quality of life measures, and post-void residual volume, with mean operative time ranging from 67-104.5 minutes. Our review shows that there is limited evidence on the use and clinical outcomes of TFL. ThuFLEP might suggest equivalence to the widely used HoLEP in the available evidence so far. TFL lithotripsy shows promising results but further prospective, randomized trials are required to properly assess its usability, clinical effectiveness and standardisation of the settings for successful adoption of the technology.

Minimally Invasive Surgery for the Treatment of Ureteric Stones - State-of-the-Art Review

The landscape of managing ureteric stones has evolved over the last few decades and several treatment options exist depending on the stone size, location, and other patient and stone factors. While open surgery is now rarely performed, the use of medical expulsive therapy (MET) has been controversial and perhaps only recommended for large distal ureteric stones. The mainstay treatment balances between shockwave lithotripsy (SWL) and ureteroscopy (URS), with the latter usually recommended for larger stones. While the principles of ureteric stone management have remained largely unchanged, the modern era has generated new methods and means to deliver it. Advancements have occurred in all domains of endourology to try and refine treatment and balance it with cost, patient choice and quality of life. Dissemination of technologies and demonstration of their efficacy and safety will eventually result in new recommendations among international guidelines and evolution of new gold standards.

Basic and advanced technological evolution of laser lithotripsy over the past decade: An educational review by the European Society of Urotechnology Section of the European Association of Urology

Laser disintegration of urinary stones is a cornerstone of urolithiasis treatment in the modern era. Despite the wide clinical use of stone lasers, basic and advanced technological achievements and developments are difficult to comprehend and interpret by the average urologist. A descriptive analysis of laser production and stone disintegration mechanisms was performed. We focused on physics of modern types of lithotripters, the construction of laser fibers, laser parameters, new modes, settings, and lithotripsy techniques. The main principle of laser emission remains the same since the first emitting laser was produced. Peak power density and short interaction time lead to photothermal effects responsible for stone disintegration. Modern lithotripters such as Holmium: YAG (low/high power, Moses technology) and thulium fiber laser show basic construction differences with the physical properties of the latter being superior, at least in in vitro studies. By adjusting lasing parameters, a wide spectrum of stone ablation from fragmentation to dusting can be achieved. New technology allows for the production of real dust. Knowledge of laser fiber construction and physical properties are useful in marketing and clinical use. Urologists should understand the physical and physiological background of the lasers used in their everyday practice for stone fragmentation.

Outcomes of thulium fibre laser for treatment of urinary tract stones: results of a systematic review

PURPOSE OF REVIEW

Lasers have become a fundamental aspect of stone treatment. Although Holmium:Yttrium-Aluminum-garnet (Ho:YAG) laser is the current gold-standard in endoscopic laser lithotripsy, there is a lot of buzz around the new thulium fibre laser (TFL). We decided to evaluate the latest data to help create an objective and evidence-based opinion about this new technology and associated clinical outcomes.

RECENT FINDINGS

Sixty full-text articles and peer-reviewed abstract presentations were included in the qualitative synthesis of this systematic review performed over the last 2 years. Current super pulsed TFL machines are capable of achieving peak powers of 500W and emit very small pulse energies of 0.025 Joules going up to 6 Joules, and capable of frequency over 2000 Hz. This makes the TFL ablate twice as fast for fragmentation, 4 times as fast for dusting, more stone dust of finer size and less retropulsion compared to the Ho:YAG laser. Because of the smaller laser fibres with the TFL, future miniaturization of instruments is also possible.

SUMMARY

Based on the review, the TFL is a potential game-changer for kidney stone disease and has a promising role in the future. However larger multicentric prospective clinical studies with long-term follow-up are needed to establish the safety and efficacy of the TFL in endourology.

Initial clinical experience with the new thulium fiber laser: first 50 cases

OBJECTIVE

To evaluate the efficacy, safety, and laser settings of thulium fiber laser (TFL) in laser lithotripsy during retrograde intrarenal surgery (RIRS) for ureteral and renal stones.

METHODS

A prospective study of the first 50 patients with ureteral and renal stones who underwent RIRS using TFL (SOLTIVE Premium, Olympus, Japan) was performed. 200 and 150 µm laser fibers were used for ureteral and renal stones, respectively. Stone size, stone density, laser-on time (LOT), and laser settings were recorded. We also assessed the ablation speed (mm³/s), laser power (W), and Joules/mm³ values for each lithotripsy.

RESULTS

A total of 50 patients were included in the study with a median (IQR) age of 66 (55.5-74) years old for patients with ureteral stones and 55 (44-61.5) years old for patients with renal stones. Most of the patients had a Charlson comorbidity index score of 0. Median (IQR) stone volume for ureteral stones was 486 (332-1250) mm³ and for renal stones was 1800 (682.8-2760) mm³. Median (IQR) stone density for ureteral and renal stones was 998 (776-1300) HU and 1200 (750-1300) HU, respectively. Median (IQR) pulse energy for ureteral stones was 0.4 (0.2-0.4) J; and for renal stones, 0.3 (0.2-0.6) J. Median pulse frequency, laser power, and laser operative time were higher in the renal stones group. The overall complication rate was low in both groups.

CONCLUSION

TFL is a safe and effective modality for lithotripsy during RIRS with minimal complication rates.

Current Status and Role of Patient-reported Outcome Measures (PROMs) in Endourology

Kidney stone disease can have a number of adverse effects on patients including quality of life. Studies assessing outcome measures in this area have largely been focused on objective assessments such as stone free rate. However, as part of the evolution to shift healthcare to a more patient centered position, patient-reported outcome measures have emerged as an improved tool to address this deficit. Key patient-reported outcome measures in Urology now include Ureteral Stent Symptom Questionnaire, Wisconsin Stone QoL Questionnaire, Cambridge Ureteric Stone PROM, Cambridge Renal Stone PROM, and Urinary Stones and Intervention Quality of Life. This article serves to provide an overview of these tools and help delineate their role in current practice.