YAG Laser Lithotripsy Research Articles

Artificial intelligence versus human touch: can artificial intelligence accurately generate a literature review on laser technologies?

To compare the accuracy of open-source Artificial Intelligence (AI) Large Language Models (LLM) against human authors to generate a systematic review (SR) on the new pulsed-Thulium:YAG (p-Tm:YAG) laser. Five manuscripts were compared. The Human-SR on p-Tm:YAG (considered to be the "ground truth") was written by independent certified endourologists with expertise in lasers, accepted in a peer-review pubmed-indexed journal (but not yet available online, and therefore not accessible to the LLMs). The query to the AI LLMs was: "write a systematic review on pulsed-Thulium:YAG laser for lithotripsy" which was submitted to four LLMs (ChatGPT3.5/Vercel/Claude/Mistral-7b). The LLM-SR were uniformed and Human-SR reformatted to fit the general output appearance, to ensure blindness. Nine participants with various levels of endourological expertise (three Clinical Nurse Specialist nurses, Urology Trainees and Consultants) objectively assessed the accuracy of the five SRs using a bespoke 10 "checkpoint" proforma. A subjective assessment was recorded using a composite score including quality (0-10), clarity (0-10) and overall manuscript rank (1-5). The Human-SR was objectively and subjectively more accurate than LLM-SRs (96 ± 7% and 86.8 ± 8.2% respectively; p < 0.001). The LLM-SRs did not significantly differ but ChatGPT3.5 presented greater subjective and objective accuracy scores (62.4 ± 15% and 29 ± 28% respectively; p > 0.05). Quality and clarity assessments were significantly impacted by SR type but not the expertise level (p < 0.001 and > 0.05, respectively). LLM generated data on highly technical topics present a lower accuracy than Key Opinion Leaders. LLMs, especially ChatGPT3.5, with human supervision could improve our practice.

Percutaneous transhepatic papillary balloon dilation combined with dual-frequency double-pulse laser lithotripsy for large-diameter common bile duct stones

Objective: To evaluate the safety and efficacy of percutaneous transhepatic papillary balloon dilation (PTPBD) combined with flexible ureteroscopy-guided dual-frequency double-pulse ND:YAG (FREDDY) laser lithotripsy (PTPBD-FREDDY) for the treatment of giant (>1.5 cm diameter) common bile duct stones. Methods: A retrospective analysis was conducted on 26 patients with large-diameter difficult choledocholithiasis admitted to two medical centers from December 2017 to October 2021. Among these patients, four could not tolerate surgery or endoscopic treatment, six experienced failure of endoscopic treatment, and 16 refused to undergo endoscopic or surgical treatment. All patients underwent the PTPBD-FREDDY procedure. The FREDDY laser lithotripsy was performed under ureteroscopic guidance, followed by a balloon to push the stones into the duodenum. The primary endpoint was the technical success rate, and the secondary endpoints included the rate of stone recurrence and related complications. Results: All 26 patients successfully completed the operation, achieving a technical success rate of 100%. The average lithotripsy frequency and operation time for bilirubin stones were significantly higher than those of mixed stones and cholesterol stones (P<0.01). The main postoperative complications included mild fever (n=3), abdominal pain (n=3), nausea (n=2) and vomiting (n=1). One patient experienced biliary tract bleeding, which improved after conservative treatment. No serious complications such as pancreatitis, sepsis, or biliary perforation were observed. After 2 years of follow-up, no cases of stone recurrence were observed. Conclusions: PTPBD-FREDDY is a safe and effective treatment for patients with giant common bile duct stones. It provides a new therapeutic option for patients with giant choledocholithiasis who can not tolerate surgery or have failed endoscopic treatment, demonstrating promising prospects.

Monitoring Intrarenal temperature changes during Ho: YAG laser lithotripsy in patients undergoing retrograde intrarenal surgery: a novel pilot study.

Ho: YAG laser lithotripsy is widely used for urinary stone treatment, but concerns persist regarding its thermal effects on renal tissues. This study aimed to monitor intrarenal temperature changes during kidney stone treatment using retrograde intrarenal surgery with Ho: YAG laser. Fifteen patients were enrolled. Various laser power settings (0.8J/10 Hz, 1.2J/12 Hz) and irrigation modes (10cc/min, 15cc/min, 20cc/min, gravity irrigation, and manual pump irrigation) were used. A sterile thermal probe was attached to a flexible ureterorenoscope and delivered into the calyceal system via the ureteral access sheath. Temperature changes were recorded with a T-type thermal probe with ± 0.1°C accuracy. Laser power significantly influenced mean temperature, with a 4.981°C difference between 14W and 8W laser power (p < 0.001). The mean temperature was 2.075°C higher with gravity irrigation and 2.828°C lower with manual pump irrigation (p = 0.038 and p = 0.005, respectively). Body mass index, laser power, irrigation model, and operator duty cycle explained 49.5% of mean temperature variability (Adj. R2 = 0.495). Laser power and operator duty cycle positively impacted mean temperature, while body mass index and specific irrigation models affected it negatively. Laser power and irrigation rate are critical for intrarenal temperature during Ho: YAG laser lithotripsy. Optimal settings and irrigation strategies are vital for minimizing thermal injury risk. This study underscores the need for ongoing research to understand and mitigate thermal effects during laser lithotripsy.

Comparison of lithotripsy methods during mini-PNL: is there a role for ballistic lithotripsy in the era of high-power lasers

BackgroundFor renal stones > 20 mm, percutaneous nephrolithotomy (PNL) offers the best stone clearance rates with acceptable complication rates. This study aimed to compare the efficiency of high-power holmium YAG laser and ballistic lithotripsy during mini-PNL.MethodsData from 880 patients who underwent mini-PNL for renal stones was investigated retrospectively. The study utilized propensity score matching to create two groups: laser lithotripsy (n = 440) and ballistic lithotripsy (n = 440). The groups were matched based on stone size, Guy’s stone score, and stone density. The main objectives of the study were to assess the stone-free rate (SFR), duration of surgery, and complication rates.ResultsThe average age of the population was 51.4 ± 7.1 years, with a mean stone size of 28.6 ± 8.3 mm and a mean stone density of 1205 ± 159 HU. There were no significant differences between the groups. The SFRs of the laser lithotripsy and ballistic lithotripsy were 92.5% and 90.2%, respectively (p = 0.23). The laser lithotripsy group had a notably shorter surgery time (40.1 ± 6.3 min) compared to the ballistic lithotripsy group (55.6 ± 9.9 min) (p = 0.03). Complication rates were similar (p = 0.67).ConclusionsOur study shows that a high-power holmium YAG laser provides quicker operation time compared to ballistic lithotripsy. However, ballistic lithotripsy is still an effective and safe option for stone fragmentation during mini-PNL. In places where a high-power holmium YAG laser is not available, ballistic lithotripters are still a safe, effective, and affordable option for mini-PNL.

Safety Parameters for the Use of Holmium:YAG Laser in the Treatment of Biliary Calculi: The Ex-Vivo Model.

Background and Objectives: While studies have demonstrated the efficacy of cholangioscopy-guided Holmium-Yttrium aluminum garnet (Ho:YAG) laser lithotripsy for the treatment of refractory bile duct stones, data regarding the safety of the operating parameters for laser lithotripsy are lacking. The aim of this study was to determine safe, yet effective, energy settings for Ho:YAG laser in the ex-vivo model. Materials and Methods: This ex vivo experimental study utilized the Ho:YAG laser on porcine bile duct epithelium and human gallstones. Ho:YAG laser lithotripsy was applied in different power settings from 8 to 15 Watts (W) to six explanted porcine bile ducts. Settings that appeared safe were then utilized to fragment seventy-three human gallstones. Results: The median bile duct perforation times with the Ho:YAG laser between 8-15 W were: >60 s (8 W); 23 s (9 W); 29 s (10 W); 27 s (12 W); 12 s (14 W); and 8 s (15 W). Statistically significant differences in the median perforation times were noted between 8 W vs. 15 W, 9 W vs. 15 W, 10 W vs. 15 W, and 12 W vs. 15 W (p < 0.05). When using a 365 µm Ho:YAG laser probe at 8-12 W, the fragmentation rates on various size stones were: 100% (<1.5 cm); 80-100% (1.6-2.0 cm) and 0-32% (>2.0 cm). Optimal fragmentation was seen utilizing 12 W with high energy (2.4 J) and low frequency (5 Hz) settings. Using a larger 550 µm probe at these settings resulted in 100% fragmentation of stones larger than 2 cm. Conclusions: The Ho:YAG laser appears to be safe and effective in the treatment of large bile duct stones when used between 8-12 W in 5 s bursts in an ex vivo model utilizing porcine bile ducts and human gallstones.

Observation and comparison of gas formation during holmium:YAG laser lithotripsy of cystine, uric acid, and calcium oxalate stones: a chromatographic and electron microscopic analysis.

The primary aim of the present in vitro study is to analyze the chemical content of the bubbles occurring during the fragmentation of cystine stones with both the high-power and low-power holmium:YAG (Ho:YAG) lasers. The secondary aim is to discuss their clinical importance. Three types of human renal calculi calcium oxalate monohydrate (COM), cystine, and uric acid were fragmented with both low-power and high-power Ho:YAG lasers in separate experimental setups at room temperature, during which time it was observed whether gas was produced. After laser lithotripsy, a cloudy white gas was obtained, after the fragmentation of cystine stones only. A qualitative gas content analysis was performed with a gas chromatography-mass spectrometry (GC-MS) device. The fragments in the aqueous cystine calculi setup were dried and taken to the laboratory to be examined by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and X-ray diffraction analysis. No gas production was observed after fragmentation in the COM and uric acid stones. Free cystine, sulfur, thiophene, and hydrogen sulfide gas were produced by both low-power and high-power Ho:YAG laser lithotripsy of the cystine stones. In the SEM-EDX mapping analysis, a free cystine molecule containing 42.8% sulfur (S), 21% oxygen (O), 14.9% carbon (C), and 21% nitrogen (N) atoms was detected in the cystine stone experimental setup. The evidence obtained, which shows that hydrogen sulfide emerges in the gaseous environment during Ho:YAG laser fragmentation of cystine stones, indicates that caution is required to prevent the risk of in vivo production and toxicity.

Do Stone Characteristics and Laser Fiber Size Affect Ho: YAG Laser Time and Energy During Ureteroscopy?

To assess the correlation of attenuation value measured as HU in Non-contrast computed tomography, stone size, location, fibre size and stone composition with Holmium: yttrium-aluminium garnet (Ho: YAG) laser parameters including, cumulative laser energy and final laser time. We prospectively analyzed 118 patients undergoing flexible/semirigid ureteroscopy and Holmium: YAG laser lithotripsy from October 2022 to October 2023 at Mogadishu Urological Centre. Our study parameters encompass preoperative stone characteristics determined in NCCT (stone size, attenuation value, and stone location), fibre size, cumulative laser energy and time, overall operative time, and postoperative stone composition analysis. There were 118 patients eligible for our prospective study. In the logistic regression model for retrograde intrarenal surgery with a fibre size of 272μm, cumulative laser energy showed a significant difference among stone size, location, fibre size, and calcium oxalate stones (P > 0.05). However, no significant difference was noticed in the attenuation value (P = 0.078) (R2 = 0.053). Our analysis showed a positive significance among all the parameters (P < 0.05) for laser time. In logistic regression for a rigid ureteroscope with a fibre size of 365μm, cumulative laser energy showed a significant difference between the location stone and fibre size (P < 0.05) (R2 = 0.09). However, no significant difference was seen among stone size, attenuation value, and calcium oxalate stones (P > 0.05). For laser time, our analysis showed a positive significance among all parameters except the calcium oxalate stones, which showed no significant difference (P > 0.05). Our study showed that stone location, hardness, and fibre size are the most critical factors influencing the outcome of Ho: YAG laser parameters. The study revealed that CaOMH stones require more time to disintegrate into smaller ones, while PH-dependent stones such as carbonate apatite may require less time to fragment.

To Evaluate the Impact of Ho:YAG Laser Lithotripsy for Ureteroscopic Removal of Proximal and Distal Ureter Calculi.

Background Urinary calculus illness is a prevalent clinical issue encountered by the medical community, particularly urologists, in contemporary society. Laser technologies have been widely accepted as standard modalities for lithotripsy applications. Using the Ho:YAG laser has expanded the range of applications for ureteroscopic stone management (URS), enabling the treatment of bigger stones in all regions of the upper urinary tract. It is noteworthy that ureteroscopy (URS) demonstrates superior rates of stone clearance for distal stones, regardless of their size, with a success rate of 94.5% compared to 74% for other treatment modalities. Significant variation exists in the reported results and problems associated with Ho:YAG laser lithotripsy across different trials, as documented in the literature. The procedure's outcome might vary based on factors such as the size of the stone, the length of impaction, the presence of ureteral damage and granulation, the kind and size of endoscopes used, and the specific energy settings employed by various operators. The present study aimed to evaluate the impact of Ho:YAG laser lithotripsy for ureteroscopic removal of proximal and distal ureter calculi. Methods This prospective observational study was carried out in the Department of Urology at DY Patil Medical College and Hospital, Pune, from March 2021 to March 2023. Patients diagnosed with a case of ureteric stone who opted for URSL during the study period were included. A total of 50 patients who underwent URSL in the urology department were included in this study. These were then grouped into those with proximal ureteral stones and distal ureteral stones. (25 each) Results The study observed that patients diagnosed with proximal ureteral stones had bigger calculi, with a mean stone size of 15mm, in comparison to patients with distal ureteral stones, with a mean stone size of 10mm (P=0.010). The stone burden was significantly higher for proximal ureteral stone patients than those with distal ureteric stones (P=0.010). The average duration of the operating procedure for upper ureter stones was 70 minutes, but for lower stones, the mean operative time was 45 minutes (P<0.001). No statistical significance was seen in the median age of patients between the two groups (P=0.89). The maximum number of cases in the upper stone group were in the age group of 16-30 years, and in the lower stone group was in the age group of 31-45 years. The prevalence of DJ stents at the time of presentation was higher among patients diagnosed with proximal ureteric stones than those with distal ureteric stones, with rates of 28% and 20%, respectively (P=0.508). Full fragmentation was successfully accomplished in all patients within the distal calculus group, accounting for 100% of the cases. At the same time, for proximal ureteric stones, a single laser lithotripsy session resulted in 92% (23 patients) achieving a stone-free status after two weeks. Conclusion The study observed that stone size, burden, and procedure duration were statistically significant among other criteria. Mean age, stone HU, prior DJ stent, and stone-free rate were statistically insignificant. The procedure indicated that Ho:YAG laser lithotripsy has efficacy in treating both proximal and distal ureteral stones, with minimal intraoperative and postoperative complications. None of the complications were due to laser energy.

Shock waves generated by toroidal bubble collapse are imperative for kidney stone dusting during Holmium:YAG laser lithotripsy

Holmium:yttrium–aluminum-garnet (Ho:YAG) laser lithotripsy (LL) has been the treatment of choice for kidney stone disease for more than two decades, yet the mechanisms of action are not completely clear. Besides photothermal ablation, recent evidence suggests that cavitation bubble collapse is pivotal in kidney stone dusting when the Ho:YAG laser operates at low pulse energy (Ep) and high frequency (F). In this work, we perform a comprehensive series of experiments and model-based simulations to dissect the complex physical processes in LL. Under clinically relevant dusting settings (Ep = 0.2 J, F = 20 Hz), our results suggest that majority of the irradiated laser energy (>90 %) is dissipated by heat generation in the fluid surrounding the fiber tip and the irradiated stone surface, while only about 1 % may be consumed for photothermal ablation, and less than 0.7 % is converted into the potential energy at the maximum bubble expansion. We reveal that photothermal ablation is confined locally to the laser irradiation spot, whereas cavitation erosion is most pronounced at a fiber tip-stone surface distance about 0.5 mm where multi foci ring-like damage outside the thermal ablation zone is observed. The cavitation erosion is caused by the progressively intensified collapse of jet-induced toroidal bubble near the stone surface (<100 μm), as a result of Raleigh-Taylor and Richtmyer-Meshkov instabilities. The ensuing shock wave-stone interaction and resultant leaky Rayleigh waves on the stone surface may lead to dynamic fatigue and superficial material removal under repeated bombardments of toroidal bubble collapses during dusting procedures in LL.

In vitro and in vivo assessment of a bilayered degradable rapamycin-eluting stent for ureteral stricture caused by holmium: YAG laser lithotripsy

Ureteral stricture caused by holmium: YAG laser lithotripsy is one of the most challenging issues for urologists. Currently, evidence for rapamycin application in reducing ureterostenosis is not sufficient. This study aimed to assess the inhibition of ureteral stricture of rapamycin-eluting stents in vitro and in vivo. A bilayered drug-eluting ureteral stent consisted of drug blending with poly (lactic-co-glycolic acid) (PU/drug stent), which was over-layered by polycaprolactone (PCL) by ultrasonic atomizing spraying. Stent morphology was observed by scanning electron microscope. A kidney-ureter-bladder model was established to simulate the stents-releasing condition, and high-performance liquid chromatography was used to measure the drug release rate. The inhibitory proliferation was detected by CCK-8. The bladder of rats was injured through electro tome, and stents were implanted for 7, 14, and 28 days. The effects of drug-eluting stents was investigated by hematoxylin-eosin staining, immunofluorescence staining, real-time quantitative polymerase chain reaction and western blot. The bilayered stents could block the burst loss of the drug and maintained a sustained delivery period because of the 5.3 μm thickness of the PCL layer. The relative growth rates of cells plotted inhibitory effect on the proliferation of human urethral scar fibroblast cells. For in vivo results of 28 days, the bilayered stent maintained structural integrity and induced less deposition of crystals, thinner and less lamina propria connective tissues were formed, and α-SMA and TGF-β1 were downregulated. Bilayered rapamycin-eluting stent is significantly effective in alleviating fibrosis in in vitro and in vivo models. Statement of significanceThe occurrence of ureteral stricture resulting from holmium: YAG laser lithotripsy presents a significant challenge for urologists. Traditional double J stents have not been proven to offer a shorter indwelling time or improved inhibition of tissue blocking. While drug-eluting stents containing rapamycin, paclitaxel, and other substances have been extensively used in treating artery stenosis, there is insufficient evidence supporting their application in reducing ureterostenosis. Consequently, a biodegradable polymer ureteric scaffold incorporating rapamycin was fabricated in this study, employing ultrasonic atomization spraying technology to optimize the bilayers composed of 75/25 poly (lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL). The efficacy of the scaffold was subsequently confirmed through in vitro and in vivo experiments.

Factors Affecting the Efficacy of Ureterorenoscopic Holmium :YAG Laser Lithotripsy in Ureteral Stones

Amaç Üreterorenoskopik (URS) litotripsi için Holmiyum:itriyum-alüminyum-garnet (Ho:YAG) lazer altın standarttır.Litoripsiyi etkileyen en önemli faktörler taş hacmi, taş yoğunluğu ve lazerin özellikleridir.Biz bu çalışmada litotripsi işleminde lazer etkinliğini objektif yöntemlerle ölçmeyi amaçladık. Materyal Metod Ekim 2020 Şubat 2022 tarihleri arasında Bakırköy Dr. Sadi Konuk Eğitim ve Araştırma Hastanesinde üreter taşları için yapılmış üreterorenoskopi lazer litotripsi (URS-LL) vakaları retro–spektif olarak incelendi.Hastaların demografik verileri, taş boyutu, taş yoğunluğu (hounsfield ünitesi( HU)) ,operasyon sırasında lazer ayarları enerji (J), güç (W) , frekans (F) toplam lazer süresi kayıt edilerek toplam enerji miktarı saptandı. Bu veriler elde edildikten sonra toplam enerji miktarı taş hacmine bölünerek 1 mm³ taş kırmak için gerekli enerji miktarı (J / mm³) hesaplandı. Ayrıca taş hacmi toplam lazer süresine bölünerek saniyede kırılan taş hacmi (mm³ / sn) hesaplandı. Bulgular Çalışmaya dahil olunan 80 hastanın ortalama yaşı 46±11.8 olarak saptandı . Hastaların 58 i (% 72.5) erkek, 22 si (%27.5) kadın idi. Hastalara sağ 42 (% 52.5), sol 38 (%47.5) URS-LL uygulandı. Hastaların median taş hacmi 285.18 ( 195-398) mm³, median taş yoğunluğu 1085 (916-1202) HU olarak saptandı. Ortalama lazer enerjisi 1.44± 0.2 joule, ortalama lazer gücü 14.38 ± 2.2 watt, ortalama frekans saniyede 12.4± 2.2 atım olarak hesaplandı. Taş fragmantasyonu için kullanılan median toplam enerji 2874 (1617- 4332) joule , median lazer süresi 224 (128-298) saniye olarak hesaplandı. 1mm³ taş kırmak için enerji miktarı 9.8 (6.4-14.2) joule . 1 saniyede kırılan median taş hacmi ise 1.56 (0.8-2.6 ) mm³ olarak hesaplandı Sonuç Üreter taşlarının etkin bir şekilde tedavisi için lazer litotripsi ile mümkün olmaktadır. Lazer litotripsinin etkinliğini ölçmek için bir saniyede kırılan taş miktarı (mm³/sn) ve 1 mm³ taşı kırmak için gerekli olan enerji miktarı (j/mm³) gibi daha objektif verilere gereksinim vardır. Bu verilerin bilinmesi üreterorenoskopik lazer litotripsi etkinliğini artırmada prediktif bir faktör olabileceği düşünülmektedir.

Uretroscopy with Laser vs ESWL in Management of Upper Ureteric Stones

Background Although SWL and Laser remain the most common modalities for the treatment of proximal ureteral stones, there is still an ongoing debate among the academicians and medical practitioners regarding the best treatment modality. Objective To compare the efficacy of ureteroscopy using holmium: YAG laser lithotripsy versus shock wave lithotripsy in management of proximal ureteric stones (≤10 mm) regarding surgical efficacy, safety and cost effectiveness. Patients and Methods This study was performed to compare ureteroscopy using holmium: YAG laser lithotripsy versus shock wave lithotripsy in management of proximal ureteric stones (≤10 mm) regarding surgical efficacy, safety and cost effectiveness. It included 52 patients with proximal ureteral stones and it was done in the period starting from September 2021 to February 2022. Results There was a statistically significant difference between the both modalities in favor of SWL as regarding the anesthesia, the overall procedural time and overall cost as SWL group were treated as an outpatient cases. There was a significant difference in used anesthesia (sedation for SWL and general anesthesia for Laser). Regarding Overall procedural time (hours), it was 4.55 ± 1.94 and was 36.88 ± 5.38 for SWL and Laser groups respectively. Overall cost; even if patients underwent three sessions of SWL, the cost between the two options was still significantly different. The overall cost of Laser was 15000 EP, with an efficiency of 80 %, while overall cost of SWL was (2500 EP), with an efficiency of 49.9 %. Conclusion Laser is more effective, has the advantage of the higher SFR from the first session without need of multiple hospital visits and prolonged radiation exposure time. SWL has lower treatment costs, while complications were comparable in both groups, so treatment decision depends on not only stone characteristics but also cost-effectiveness ratio and this should be considered when counseling the patient with proximal ureteric stone. Larger sample size is required for more convenience data.

Comparison of three techniques in bladder stone surgery: Which technique is more effective and safe?

In our study, we aimed to compare the success and complication rates of percutaneous cystolithotripsy (PCCL), transurethral cystolithotripsy (TUCL), and Ho: YAG laser lithotripsy in the surgery of bladder stones that occurred due to various reasons. Patients diagnosed with single or multiple bladder stones with long axis larger than 2 cm, resulting for various reasons, were included in ou study. Sizes of the stones, cystolithotripsy and discharge times, catheter removal times, complications observed, and the visual pain scale (VPS) were retrospectively evaluated separately from the surgical techniques implemented for accompanying patients and their data. TUCL (group 1) was implemented in 40, PCCL (group 2) was implemented in 44, and transurethral Ho: YAG laser lithotripsy (group 3) was implemented in 30 of the 121 patients included in the study. The bladder stone long axe group 1 average was 3,7 cm (2,2-5,3), group 2 average was 3,74 cm (2,1-5,1), and group 3 average was 3,7 cm (2,3-4,7). Urethral stricture evolved in two patients who underwent TUCL. A statistically significant difference was observed on behalf of PCCL in terms of operation time. There was significance in the Ho: YAG laser cystolithotripsy group in comparison with VPS scores. No significant differences were found in terms of age, stone size, urethral catheter removal times, and discharge times. The average follow-up time was 6 months. Although all three methods were quite successful in bladder stone surgery, average cystolithotripsy times were significantly low in the PCCL technique. Thinking that the most common cause of bladder stone is BPH, it is stated that the suprapubic inserted tube ease the bladder drainage during transurethral resection of the prostate (TUR-P). In this way, the duration of the most common accompanying surgeries is shortened and performed more safely.

Evaluating the clinical outcomes of thulium fiber laser (TFL) in comparison to holmium laser in the treatment of urinary tract stones – A systematic review

Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) had been considered the gold standard for treating urinary tract stones. However, advancements in laser technology have introduced thulium fiber laser (TFL) as a potential alternative. Preliminary studies have indicated that TFL may have certain advantages over Ho:YAG laser in lithotripsy. This systematic review compared the clinical outcomes of TFL and Ho:YAG laser for urinary tract stone treatment, focusing on operating time, stone-free rate (SFR), retropulsion, and complications. A systematic search was conducted on PubMed and ScienceDirect for original articles published within the last 5 years, comparing the clinical outcomes of Ho:YAG and TFL in lithotripsy. Inclusion criteria were English-language studies focusing on Ho:YAG and TFL laser energy for urinary tract stones, with accessible full-text articles comparing clinical outcomes. Excluded were studies discussing lasers for conditions other than urinary tract stones or using lasers other than TFL and Ho:YAG. Four studies (544 procedures) met the criteria and underwent risk of bias assessment using Risk of Bias 2 (ROB-2) for randomized trials and Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) for cohort studies. The data were presented in tables and charts. In this review, TFL demonstrated a shorter operating time compared to Ho:YAG (and higher stone-free rates in two studies. TFL also had a lower incidence of stone retropulsion. Intra-operative complication rates varied between the groups for ureterorenoscopy (URS) and retrograde intrarenal surgery (RIRS) procedures, while TFL had a higher rate of prolonged haematuria during mini percutaneous nephrolithotomy (PCNL) procedures. Postoperative complications were similar in both groups. Limitations of this review include procedural and laser setting heterogeneity, a small number of studies, and the lack of registration and protocols. In conclusion, TFL is an effective and safe alternative to Ho:YAG laser for lithotripsy, offering shorter operation time, higher stone-free rates, and reduced stone retropulsion.

URERTEROSCOPIC LASER LITHOTRIPSY IS BETTER THAN PNEUMATIC LITHOTRIPSY FOR URETRIC STONES

Background: Among various intra-corporeal lithotripters, pneumatic lithotripter has become the widely used tool for the treatment of urinary stones. Recently the holmium: YAG laser has been used with a wide range of potential urological applications, including intra-corporeal lithotripsy of urinary calculi. Aims and objective: Compare the effectiveness and complications of treatment for ureteric stones between holmium laser lithotripsy and pneumatic lithotripsy. Material and Methods: Comparison of 100 patients presented with ureteric stones, group one (50) of whom were treated with pneumatic lithotripsy and group two (50) with holmium laser was done and the effectiveness and complications of both were analyzed. Results: There was no difference in patient age, sex, stone size and location of stones between the two groups. The immediate stone free rates were 86% in the holmium: YAG group and 64% in the pneumatic lithotripsy group (p = 0.011).. The mean operative time in the holmium: YAG group (35.7±3.2) was shorter than those with pneumatic lithotripsy group (50.2±5.3). Postoperative stay in hospital was less than 24 hours in holmium: YAG group (74%) and shorter than those for pneumatic group (36%) (p &lt; 0.002). Post treatment complications such as ureteral perforation were encountered in only three patients who underwent pneumatic lithotripsy. Other complications, such as mucosal injury, ureteral perforation and postoperative fever; there was no statistically signicant difference between the two groups. While light hematuria was found more frequently in the pneumatic group (10%) in comparison to laser group (4%) (p = 0.045). On the other hand, the overall complication rates between the two groups was statistically signicant (10%) laser group vs. (36%) pneumatic group (p = 0.002). Conclusions: Holmium: YAG laser lithotripsy was associated with shorter operation time and postoperative hospitalization period. We believe that Holmium: YAG laser lithotripsy is an excellent treatment modality for managing ureteral calculi in central Rajasthan where stone formation rate is quite high. Drawback of holmium laser lithotripsy is its cost and maintainance

HO:YAG LASER VS PNEUMATIC LITHOTRIPSY WITH SEMI RIGID URETEROSCOPE FOR PROXIMAL URETERAL CALCULI : OUR INSTITUTIONAL EXPERIENCE

Introduction &amp; objectives: Different modalities are available for proximal ureteric stone fragmentation. From them pneumatic and holmium: yttrium-aluminum-garnet lithotripsy has favorable outcomes. In our randomized study, we included 100 patients who underwent semi rigid ureteroscopic pneumatic lithotripsy or laser lithotripsy. This study aims to compare the outcome of PL and LL in the management of upper ureteric calculi. 100 patients were a Materials &amp; methods: dmitted in Govt Kilpauk medical college and hospital between January 2021 to June 2022 &amp; randomized 50 cases of URS with pneumatic lithotripter and 50 cases of URS with laser lithotripter were enrolled. Patients with urinary tract infection, radiolucent stones, loss of follow-up, concurrent middle or lower third ureteral stones or acute renal failure were excluded. All patients underwent semi-rigid URS with Ho:YAG laser or pneumatic lithotripsy followed by DJ stenting. The aim of this study to compare the stone-free rate, assess the complications, duration of surgery and assess the need for second procedure , if retropulsion of calculus occurred following PL and LL. Demographically, no s Results: tatistical different in both groups in view of age, gender, mean size of stones (P&gt; 0.05). Retropulsion occurred in 16% of the PL group (P&lt; 0.05) and required auxillary procedure. There was a statistical difference in terms of stone free rate of stone in favor of LL group (p≤0.05) and mean operative time in favor of the PL group (p≤ 0.05). Conclusions: In both techniques, acceptable results were achieved. We found that both the PL and LL approaches were effective and safe for proximal ureteric calculi. LL method had advantages in more stone free rate, lower retropulsion rate but longer procedure duration compare to the PL method

MP05-08 POSSIBLE ROLE OF THE MICROBIOTA IN URINARY STONES: A PROSPECTIVE STUDY TO CORRELATE RADIOLOGICAL DENSITY (HOUNSFIELD UNITS) AND CULTURAL EXAMINATION OF URINARY CALCULI

You have accessJournal of UrologyCME1 Apr 2023MP05-08 POSSIBLE ROLE OF THE MICROBIOTA IN URINARY STONES: A PROSPECTIVE STUDY TO CORRELATE RADIOLOGICAL DENSITY (HOUNSFIELD UNITS) AND CULTURAL EXAMINATION OF URINARY CALCULI Antonio Luigi Pastore, Yazan Al salhi, Andrea Fuschi, Alessia Martoccia, Fabio Maria Valenzi, Alessandro Sciarra, Stefano Salciccia, De Nunzio Cosimo, Andrea Tubaro, Costantino Leonardo, Giorgio Franco, Silvio Scalzo, Paolo Pietro Suraci, Onofrio Antonio Rera, Alice Antonioni, and Antonio Carbone Antonio Luigi PastoreAntonio Luigi Pastore More articles by this author , Yazan Al salhiYazan Al salhi More articles by this author , Andrea FuschiAndrea Fuschi More articles by this author , Alessia MartocciaAlessia Martoccia More articles by this author , Fabio Maria ValenziFabio Maria Valenzi More articles by this author , Alessandro SciarraAlessandro Sciarra More articles by this author , Stefano SalcicciaStefano Salciccia More articles by this author , De Nunzio CosimoDe Nunzio Cosimo More articles by this author , Andrea TubaroAndrea Tubaro More articles by this author , Costantino LeonardoCostantino Leonardo More articles by this author , Giorgio FrancoGiorgio Franco More articles by this author , Silvio ScalzoSilvio Scalzo More articles by this author , Paolo Pietro SuraciPaolo Pietro Suraci More articles by this author , Onofrio Antonio ReraOnofrio Antonio Rera More articles by this author , Alice AntonioniAlice Antonioni More articles by this author , and Antonio CarboneAntonio Carbone More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003216.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The aim of the study is to evaluate a possible correlation between the hardness of the urinary stone expressed in Hounsfield Units and the bacterial contamination by cultural examination of the lithiasic fragments obtained after endoscopic treatment (ureteral lithotripsy and retrograde intrarenal surgery). METHODS: This prospective study investigated patients with unilateral urinary lithiasis (ureteral and / or renal) who underwent endoscopic lithotripsy between January and December 2021. All patients were studied preoperatively with Uro-CT scan, measuring the Hounsfield Units, the number and size of the calculi for each patient. Two lithiasic fragments were extracted at the end of each procedure (one from the core and one from the periphery of the stone) and sent for chemical-physical and cultural examination. RESULTS: Seventy-three patients were enrolled and studied prospectively. 56 submitted to ureteral Holmium Yag Laser lithotripsy and 17 to RIRS. The chemical-physical evaluation showed 92% of the stones made up of calcium oxalate, 4% of calcium phosphate, 2% of uric acid and 2% of various composition. The bacterial analysis of the fragments showed a positive culture in 68% of cases, with positive Staphylococcus Epidermidis in 46% of cases, Proteus Mirabilis in 24%, Escherichia Coli in 23% and 7% with other microorganisms. The correlation between stone core culture and formation HU was statistically significant, with Staphylococcus Epidermidis associated with a mean Hounsfield value of 1234 HU; Proteus Mirabilis with average Hounsfield 872 HU; Escherichia Coli with mean Hounsfield 642 HU (p values <0.0001). The mean radiological density in the negative culture urinary stones was 843 HU. CONCLUSIONS: Our study demonstrates a statistically significant correlation between urinary stone infection and its radiological density (HU). We postulate that the correlation between the stone core isolated microorganism and the calculi hardness (HU) might impact on the treatment choice and results (stone free rate). Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e46 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Antonio Luigi Pastore More articles by this author Yazan Al salhi More articles by this author Andrea Fuschi More articles by this author Alessia Martoccia More articles by this author Fabio Maria Valenzi More articles by this author Alessandro Sciarra More articles by this author Stefano Salciccia More articles by this author De Nunzio Cosimo More articles by this author Andrea Tubaro More articles by this author Costantino Leonardo More articles by this author Giorgio Franco More articles by this author Silvio Scalzo More articles by this author Paolo Pietro Suraci More articles by this author Onofrio Antonio Rera More articles by this author Alice Antonioni More articles by this author Antonio Carbone More articles by this author Expand All Advertisement PDF downloadLoading ...

Plasma formation in holmium:YAG laser lithotripsy.

Duringholmium:yttrium-aluminum-garnet(holmium:YAG) laser lithotripsy to break urinary stones, urologists frequently see flashes of light. As infrared laser pulses are invisible, what is the source of light? Here we studied the origin, characteristics, and some effects of flashes of light in laser lithotripsy. Ultrahigh-speed video-microscopy was used to record single laser pulses at 0.2-1.0 J energy lasered with 242 µm glass-core-diameter fibers in contact with whole surgically retrieved urinary stones and hydroxyapatite (HA)-coated glass slides in air and water. Acoustic transients were measured with a hydrophone. Visible-light and infrared photodetectors resolved temporal profiles of visible-light emission and infrared-laser pulses. Temporal profiles of laser pulses showed intensity spikes of various duration and amplitude. The pulses were seen to produce dim light and bright sparks with submicrosecond risetime. The spark produced by the intensity spike at the beginning of laser pulse generated a shock wave in the surrounding liquid. The subsequent sparks were in a vapor bubble and generated no shock waves. Sparks enhanced absorption of laser radiation, indicative of plasma formation and optical breakdown. The occurrence and number of sparks varied even with the same urinary stone. Sparks were consistently observed at laser energy >0.5 J with HA-coated glass slides. The slides broke or cracked by cavitation with sparks in 63 ± 15% of pulses (1.0 J, N = 60). No glass-slide breakage occurred without sparks (1.0 J, N = 500). Unappreciated in previous studies, plasma formation with free-running long-pulse holmium:YAG lasers can be an additional physical mechanism of action in laser procedures.

Láser de fibra de tulio: ¿revolucionario o frenesí mediático?

Abstract Description: The Holmium: yttrium-aluminum-garnet (Ho:YAG) laser has become the gold-standard intracorporeal lithotripsy device since it was first introduced in the 1980’s. More recently, the Thulium Fiber Laser (TFL) was introduced into the clinical setting, with the potential to address some of the inherent limitations with Ho:YAG devices. In particular, early experience suggested the TFL provided enhanced dusting and fragmenting capabilities, less retropulsion and better stone free rates compared to the Ho:YAG laser. Relevance: Should the initial claims of the TFL’s better dusting properties be confirmed, this would be a significant advancement in the field. The ability to dust larger stones more rapidly could enhance the role of ureteroscopy and reduce the need for more invasive procedures. Conclusion: The initial experience with the TFL is promising and suggests an advantage over Ho:YAG laser lithotripsy. Properly conducted prospective randomized trials are required to further delineate the advantages, disadvantages and to optimize patient outcomes.

Understanding the Role of Ureteral Access Sheath in Preventing Post-Operative Infectious Complications in Stone Patients Treated with Ureteroscopy and Ho:YAG Laser Lithotripsy: Results from a Tertiary Care Referral Center.

The use of ureteral access sheaths (UAS) limits the irrigation-induced increase in intrarenal pressure during ureteroscopy (URS). We investigated the relationship between UAS and rates of postoperative infectious complications in stone patients treated with URS. Data from 369 stone patients treated with URS from September 2016 to December 2021 at a single institution were analyzed. UAS (10/12 Fr) placement was attempted in case of intrarenal surgery. The chi-square test was used to assess the relationship between the use of UAS and fever, sepsis, and septic shock. Univariable and multivariable logistic regression analyses tested the association of patients' characteristics and operative data and the rate of postoperative infectious complications. Full data collection of 451 URS procedures was available. Overall, UAS was used in 220 (48.8%) procedures. As for postoperative infectious sequalae, we recorded fever (n = 52; 11.5%), sepsis (n = 10; 2.2%), and septic shock (n = 6; 1.3%). Of those, UAS was not used in 29 (55.8%), 7 (70%), and 5 (83.3%) cases, respectively (all p > 0.05). At multivariable logistic regression analysis, performing URS without UAS was not associated with the risk of having fever and sepsis, but it increased the risk of septic shock (OR = 14.6; 95% CI = 1.08-197.1). Moreover, age-adjusted CCI score (for fever-OR = 1.23; 95% CI = 1.07-1.42, sepsis-OR = 1.47; 95% CI = 1.09-1.99, and septic shock-OR = 1.61; 95% CI = 1.08-2.42, respectively), history of fever secondary to stones (for fever-OR = 2.23; 95% CI = 1.02-4.90) and preoperative positive urine culture (for sepsis-OR = 4.87; 95% CI = 1.12-21.25) did emerge as further associated risk factors. The use of UAS emerged to prevent the onset of septic shock in patients treated with URS, with no clear benefit in terms of fever and sepsis. Further studies may help clarify whether the reduction in fluid reabsorption load mediated by UAS is protective against life-threatening conditions in case of infectious complications. The patients' baseline characteristics remain the main predictors of infectious sequelae in a clinical setting.