ZIF-8 Vibrational Spectra: Peak Assignments and Defect Signals.

Zeolitic imidazolate framework (ZIF-8) is a promising material for gas separation applications. It also serves as a prototype for numerous ZIFs, including amorphous ones, with a broader range of possible applications, including sensors, catalysis, and lithography. It consists of zinc coordinated with 2-methylimidazolate (2mIm) and has been synthesized with methods ranging from liquid-phase to solvent-free synthesis, which aim to control its crystal size and shape, film thickness and microstructure, and incorporation into nanocomposites. Depending on the synthesis method and postsynthesis treatments, ZIF-8 materials may deviate from the nominal defect-free ZIF-8 crystal structure due to defects like missing 2mIm, missing zinc, and physically adsorbed 2mIm trapped in the ZIF-8 pores, which may alter its performance and stability. Infrared (IR) spectroscopy has been used to assess the presence of defects in ZIF-8 and related materials. However, conflicting interpretations by various authors persist in the literature. Here, we systematically investigate ZIF-8 vibrational spectra by combining experimental IR spectroscopy and first-principles molecular dynamics simulations, focusing on assigning peaks and elucidating the spectroscopic signals of putative defects present in the ZIF-8 material. We attempt to resolve conflicting assignments from the literature and to provide a comprehensive understanding of the vibrational spectra of ZIF-8 and its defect-induced variations, aiming toward more precise quality control and design of ZIF-8-based materials for emerging applications.

Avoiding "Needless" nephrectomy: What is the role of small renal mass biopsy in 2024?

Current guidelines do not mandate routine preoperative renal mass biopsy (RMB) for small renal masses (SRMs), which results in a considerable rate (18%-26%) of needless nephrectomy/partial nephrectomy for benign renal tumors. In light of this ongoing practice, a narrative review was conducted to examine the role of routine RMB for SRM. First, arguments justifying the current non-biopsy approach to SRM are critically reviewed and contested. Second, as a standalone procedure, RMB is critically assessed; RMB was found to have higher sensitivity, specificity, and an equal or lower complication rate when compared with other commonly preoperatively biopsied solid organ tumors (e.g., breast, prostate, lung, pancreas, thyroid, and liver). Based on the foregoing information, we propose a paradigm shift in SRM management, advocating for an updated policy in which partial nephrectomy or nephrectomy for SRM invariably occurs only after a preoperative biopsy confirms that a SRM is indeed malignant.

Surgical Force: Initial Study and Clinical Implications in the Assessment of Ureteral Access Sheath Induced Injury.

Purpose: Ureteral access sheaths (UAS) pose the risk of severe ureteral injury. Our prior studies revealed forces ≤6 Newtons (N) prevent ureteral injury. Accordingly, we sought to define the force urologists and residents in training typically use when placing a UAS. Materials and Methods: Among urologists and urology residents attending two annual urological conferences in 2022, 121 individuals were recruited for the study. Participants inserted 12F, 14F, and 16F UAS into a male genitourinary model containing a concealed force sensor; they also provided demographic information. Analysis was completed using t-tests and Chi-square tests to identify group differences when passing a 16F sheath UAS. Participant traits associated with surpassing or remaining below a minimal force threshold were also explored through polychotomous logistic regression. Results: Participant force distributions were as follows: ≤4N (29%), >6N (45%), and >8N (32%). More years of practice were significantly associated with exerting >6N relative to forces between 4N and 6N; results for >8N relative to 4N and 8N were similar. Compared to high-volume ureteroscopists (those performing >20 ureteroscopies/month), physicians performing ≤20 ureteroscopies/month were significantly less likely to exert forces ≤4N (p = 0.017 and p = 0.041). Of those surpassing 6N and 8N, 15% and 18%, respectively, were high-volume ureteroscopists. Conclusions: Despite years of practice or volume of monthly ureteroscopic cases performed, most urologists failed to pass 16F access sheaths within the ideal range of 4N to 6N (74% of participants) or within a predefined safe range of 4N to 8N (61% of participants).

Utility and impact of magnetic resonance elastography in the clinical course and management of chronic liver disease.

We aimed to characterize scenarios where magnetic resonance elastography (MRE) of the liver was ordered and its impact on clinical course and management. 96 consecutive MRE examinations and subsequent encounters over 14 months were reviewed. Indication for MRE of the liver and subsequent management were abstracted from the medical record. In all cases, non-invasive assessment of liver fibrosis was the primary indication and at least one additional rationale was noted. There was a significant decrease in recommendations to undergo liver biopsy after MRE. Additionally, a greater percentage of those recommended to undergo biopsy completed the procedure after discussion of the results. Given the significant cost and rare but serious risks of liver biopsy, MRE of the liver provides an attractive, safer alternative that may have a comparable impact on management, or select cases where biopsy is essential to guide management. We demonstrate the versatility of MRE in real-world hepatology practice, including its utility as a non-invasive surrogate for liver biopsy.

Alkaline Water: Help or Hype for Uric Acid and Cystine Urolithiasis?

PURPOSE: The consumption of alkaline water, water with an average pH of 8 to 10, has been steadily increasing globally as proponents claim it to be a healthier alternative to regular water. Urinary alkalinization therapy is frequently prescribed in patients with uric acid and cystine urolithiasis, and as such we analyzed commercially available alkaline waters to assess their potential to increase urinary pH. MATERIALS AND METHODS: Five commercially available alkaline water brands (Essentia, Smart Water Alkaline, Great Value Hydrate Alkaline Water, Body Armor SportWater, and Perfect Hydration) underwent anion chromatography and direct chemical measurements to determine the mineral contents of each product. The alkaline content of each bottle of water was then compared to that of potassium citrate (the gold standard for urinary alkalinization) as well as to other beverages and supplements used to augment urinary citrate and/or the urine pH. RESULTS: The pH levels of the bottled alkaline water ranged from 9.69 to 10.15. Electrolyte content was minimal, and the physiologic alkali content was below 1 mEq/L for all brands of alkaline water. The alkali content of alkaline water is minimal when compared to common stone treatment alternatives such as potassium citrate. In addition, several organic beverages, synthetic beverages, and other supplements contain more alkali content than alkaline water, and can achieve the AUA and European Association of Urology alkali recommendation of 30 to 60 mEq per day with ≤ 3 servings/d. CONCLUSIONS: Commercially available alkaline water has negligible alkali content and thus provides no added benefit over tap water for patients with uric acid and cystine urolithiasis.

Data-Driven Design of Polymer-Based Biomaterials: High-throughput Simulation, Experimentation, and Machine Learning.

Polymers, with the capacity to tunably alter properties and response based on manipulation of their chemical characteristics, are attractive components in biomaterials. Nevertheless, their potential as functional materials is also inhibited by their complexity, which complicates rational or brute-force design and realization. In recent years, machine learning has emerged as a useful tool for facilitating materials design via efficient modeling of structure-property relationships in the chemical domain of interest. In this Spotlight, we discuss the emergence of data-driven design of polymers that can be deployed in biomaterials with particular emphasis on complex copolymer systems. We outline recent developments, as well as our own contributions and takeaways, related to high-throughput data generation for polymer systems, methods for surrogate modeling by machine learning, and paradigms for property optimization and design. Throughout this discussion, we highlight key aspects of successful strategies and other considerations that will be relevant to the future design of polymer-based biomaterials with target properties.

Efficient and Accurate Computed Tomography-Based Stone Volume Determination: Development of an Automated Artificial Intelligence Algorithm.

PURPOSE: Given the shortcomings of current stone burden characterization (maximum diameter or ellipsoid formulas), we sought to investigate the diagnostic accuracy and precision of a University of California, Irvine-developed artificial intelligence (AI) algorithm for determining stone volume determination. MATERIALS AND METHODS: A total of 322 noncontrast CT scans were retrospectively obtained from patients with a diagnosis of urolithiasis. The largest stone in each noncontrast CT scan was designated the "index stone." The 3D volume of the index stone using 3D Slicer technology was determined by a validated reviewer; this was considered the "ground truth" volume. The AI-calculated index stone volume was subsequently compared with ground truth volume as well with the scalene, prolate, and oblate ellipsoid formulas estimated volumes. RESULTS: There was a nearly perfect correlation between the AI-determined volume and the ground truth (R=0.98). While the AI algorithm was efficient for determining the stone volume for all sizes, its accuracy improved with larger stone size. Moreover, the AI stone volume produced an excellent 3D pixel overlap with the ground truth (Dice score=0.90). In comparison, the ellipsoid formula-based volumes performed less well (R range: 0.79-0.82) than the AI algorithm; for the ellipsoid formulas, the accuracy decreased as the stone size increased (mean overestimation: 27%-89%). Lastly, for all stone sizes, the maximum linear stone measurement had the poorest correlation with the ground truth (R range: 0.41-0.82). CONCLUSIONS: The University of California, Irvine AI algorithm is an accurate, precise, and time-efficient tool for determining stone volume. Expanding the clinical availability of this program could enable urologists to establish better guidelines for both the metabolic and surgical management of their urolithiasis patients.

Electromotive Drug Administration in the Porcine Renal Pelvis: First Report.

Introduction: Electromotive Drug Administration (EMDA) amplifies drug delivery deep into targeted tissues. We tested, for the first time, the ability of EMDA to deliver methylene blue into the urothelium of the renal pelvis. Materials and Methods: In an anesthetized female pig, both proximal ureters were transected two inches distal to the ureteropelvic junction. An 8F dual lumen catheter and a 5F fenestrated catheter with an indwelling silver wire were inserted into both renal pelvises following which methylene blue (0.1%) was infused at a rate of 5 mL/min for 20 minutes. In one pelvis, a 4 mA positive pulsed electrical current was applied to the silver wire. Results: In contrast to the control pelvis, the EMDA side macroscopically exhibited dense homogeneous staining; microscopy revealed penetration of methylene blue into the urothelium/lamina propria. Conclusion: In the porcine renal pelvis, application of EMDA increased the penetration of a charged molecule into the urothelium/lamina propria.

A Nanocavitation Approach to Understanding Water Capture, Water Release, and Framework Physical Stability in Hierarchically Porous MOFs.

Chemically stable metal-organic frameworks (MOFs) featuring interconnected hierarchical pores have proven to be promising for a remarkable variety of applications. Nevertheless, the framework's susceptibility to capillary-force-induced pore collapse, especially during water evacuation, has often limited practical applications. Methodologies capable of predicting the relative magnitudes of these forces as functions of the pore size, chemical composition of the pore walls, and fluid loading would be valuable for resolution of the pore collapse problem. Here, we report that a molecular simulation approach centered on evacuation-induced nanocavitation within fluids occupying MOF pores can yield the desired physical-force information. The computations can spatially pinpoint evacuation elements responsible for collapse and the chemical basis for mitigation of the collapse of modified pores. Experimental isotherms and difference-electron density measurements of the MOF NU-1000 and four chemical variants validate the computational approach and corroborate predictions regarding relative stability, anomalous sequence of pore-filling, and chemical basis for mitigation of destructive forces.

Comparison of Ureteral Stent Biomaterials: Encrustation Profile in Lithogenic Artificial Urine Models.

Ureteral stent encrustation significantly limits indwelling time and can lead to downstream urological problems. However, no ideal polymeric biomaterials have been shown to completely resist encrustation in long-term urine exposure. Recently, 2-hydroxyethyl methacrylate (HEMA)-coated Pellethane was reported as a promising biomaterial resistant to encrustation. This study compared HEMA-coated Pellethane to commercially available stents under two different artificial urine environments. To evaluate the degree and composition of encrustation on HEMA-coated Pellethane, Boston Scientific Tria, Bard InLay Optima, Cook Universa Hydrogel, and Cook Black Silicone stents were used at various dwelling times in two different artificial urine environments. In a batch-flow model, samples of stents were suspended in an artificial urine solution (AUS) at 37 °C. Every 24 h for 11 weeks, 50% of the AUS would be replaced with fresh components using a programmable peristaltic pump system. The stent materials were removed at suitable time intervals and air-dried for 24 h under sterile conditions before follow-up analysis. SEM was used to assess the degree of encrustation, and inductively coupled plasma mass spectrometry (ICP-MS) was employed to quantify the encrusted compositions, specifically for calcium, magnesium, and phosphorus. We measured the weight gain over time due to encrusted deposits on the stents and quantified the amount of Ca, Mg, and P deposited on each encrusted stent. After the 11 week trial, HEMA-coated Pellethane showed the most average mass change. SEM showed that HEMA-coated Pellethane was fully encrusted in just 2 weeks in the AUS environments, and ICP-MS showed that Ca is the most abundant deposit. Among all the tested stents, Black Silicone performed the best. The two AUSs were formulated to encrust more rapidly than physiological conditions. HEMA-coated Pellethane is not an ideal stent material, while silicone is a promising material for advancing ureteral stents.

The Impact of Diabetes on Morbidity and Mortality Following Thyroidectomy.

OBJECTIVES: To explore the association between diabetes and outcomes in thyroidectomy patients. METHODS: This retrospective cohort analysis used the 2015-2017 American College of Surgeons National Surgery Quality Improvement Program database. Current Procedural Terminology (CPT) codes were used to identify thyroidectomy cases (60210, 60212, 60220, 60225, 60240, 60252, 60254, 60260, 60270, and 60271). Demographics, comorbidities, and complication incidences were compared between diabetic and nondiabetic patients using Pearson's chi-square test/Fisher's exact test as appropriate. The independent effect of diabetes on outcomes was analyzed using binary logistic regression. RESULTS: A total of 47,776 (95.4%) nondiabetic and 2307 (4.6%) diabetic patients undergoing thyroidectomy were identified from 2015 to 2017. Chi-square analysis demonstrated that diabetic patients had higher incidences of obesity (55.2% vs. 33.2%; p < 0.001), dyspnea (12.7% vs. 4.8%; p < 0.001), poor functional status (1.9% vs. 0.4%; p < 0.001), ventilator dependence (0.6% vs. 0.1%; p < 0.001), chronic obstructive pulmonary disease (COPD; 6.8% vs. 2.2%; p < 0.001), congestive heart failure (1.1% vs. 0.3%; p < 0.001), acute renal failure (0.3% vs. 0.0%; p < 0.001), hypertension (79.2% vs. 32.4%; p < 0.001), dialysis (2.0% vs. 0.4%; p < 0.001), open wound (1.1% vs. 0.1%; p < 0.001), steroid use (5.3% vs. 2.3%; p < 0.001), bleeding disorders (3.6% vs. 0.9%; p < 0.001), preoperative blood transfusions (0.2% vs. 0.0%; p = 0.001), and systemic sepsis (1.0% vs. 0.3%; p < 0.001). Demographic characteristics were significantly different between the cohorts including gender (p < 0.001), age (p < 0.001), race (p < 0.001), and Hispanic ethnicity (p = 0.033). After adjusting for these factors, logistic regression analyses showed that diabetes was associated with acute renal failure (OR: 5.836; 95% CI: 1.060-32.134; p = 0.043), wound disruption (OR: 6.194; 95% CI: 1.752-21.900; p = 0.005), prolonged length of stay (OR: 1.430; 95% CI: 1.261-1.622; p < 0.001), unplanned readmission (OR: 1.380; 95% CI: 1.096-1.737; p = 0.006), superficial incisional surgical site infections (OR: 0.240; 95% CI: 0.058-0.995; p = 0.049), urinary tract infection occurrences (OR: 2.173; 95% CI: 1.186-3.980; p = 0.012), organ space surgical site infection occurrences (OR: 3.322; 95% CI: 1.016-10.864; p = 0.047), pneumonia occurrences (OR: 2.091; 95% CI: 1.125-3.884; p = 0.020), any medical complication (OR: 1.697; 95% CI: 1.246-2.313; p = 0.001), and any complication (OR: 1.495; 95% CI: 1.136-1.968; p = 0.004). CONCLUSION: Diabetes mellitus is a significant factor associated with increased odds of complications following thyroidectomy. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:3628-3632, 2023.

Evaluation of Renal Function and Stent Durability Following Resonance Stent Placement for Benign Disease.

Introduction: The metal-based Resonance stent (RS) has traditionally been placed in patients with malignant ureteral obstruction; as such, the long-term utility of RS among patients with benign ureteral obstruction (BUO) remains underinvestigated. Methods: We retrospectively reviewed our database for patients with BUO who underwent RS placement between 2010 and 2020. The impact of chronic RS placement on renal function was evaluated by estimated serum creatinine-based glomerular filtration rate (eGFR), furosemide renal scan, and CT-based renal parenchymal volume measurement. The number of and reason for RS stent exchanges during the follow-up period, incidence of encrustation, and the average indwell time were recorded. A cost analysis of placing the RS vs a polymeric stent was performed. Results: Among 43 RS patients with BUO, at a mean follow-up of 26 months, there was no change in eGFR (p = 0.99), parenchymal volume (p = 0.44), or split renal function of the stent-bearing side on renal scan (p = 0.48). The mean RS indwell time was 9.7 months. Eleven patients (26%) underwent premature stent replacement (6 cases) or removal (5 cases). Stents in 9 patients (32%) were encrusted, of which 4 (44%) required laser lithotripsy. Overall, 25 patients (58%) and 12 patients (28%) had a mean stent indwell time of ≥6 months and ≥12 months, respectively. Placing an RS resulted in a 52%, 37%, and 5.6% cost reduction compared with a regular polymeric stent placement, where it was exchanged every 6, 4, or 3 months, respectively. Conclusions: RS deployment in the patient with a BUO results in cost-effective maintenance of renal function and of renal parenchymal volume at a mean follow-up of 2 years; however, only 28% of patients fulfilled the 1-year criterion for RS indwell time.

Sequence Patterning, Morphology, and Dispersity in Single-Chain Nanoparticles: Insights from Simulation and Machine Learning.

Single-chain nanoparticles (SCNPs) are intriguing materials inspired by proteins that consist of a single precursor polymer chain that has collapsed into a stable structure. In many prospective applications, such as catalysis, the utility of a single-chain nanoparticle will intricately depend on the formation of a mostly specific structure or morphology. However, it is not generally well understood how to reliably control the morphology of single-chain nanoparticles. To address this knowledge gap, we simulate the formation of 7680 distinct single-chain nanoparticles from precursor chains that span a wide range of, in principle, tunable patterning characteristics of cross-linking moieties. Using a combination of molecular simulation and machine learning analyses, we show how the overall fraction of functionalization and blockiness of cross-linking moieties biases the formation of certain local and global morphological characteristics. Importantly, we illustrate and quantify the dispersity of morphologies that arise due to the stochastic nature of collapse from a well-defined sequence as well as from the ensemble of sequences that correspond to a given specification of precursor parameters. Moreover, we also examine the efficacy of precise sequence control in achieving morphological outcomes in different regimes of precursor parameters. Overall, this work critically assesses how precursor chains might be feasibly tailored to achieve given SCNP morphologies and provides a platform to pursue future sequence-based design.

Visible light-assisted chemistry of vinyl azides and its applications in organic synthesis.

Vinyl azides have emerged as highly versatile precursors in organic synthesis due to their rich reactivity driven by the excellent leaving-group ability of molecular nitrogen. Over the years, significant advancement has been achieved in the manipulation of vinyl azides for the construction of C-C and C-X bonds. Typical methods involve the application of transition metals and strong oxidants for the conversion of vinyl azides into useful compounds employing harsh reaction conditions coupled with intense product purification. In this regard, visible light chemistry has become one of the most exciting fields in organic synthesis for being mild, sustainable, and often orthogonal to conventional approaches. Visible light-induced reactions involving vinyl azides generate either 2H-azirines or iminyl radicals as key intermediates, which may undergo further useful transformations to form the desired cyclic or acyclic products. Herein, we provide the most significant transformations of vinyl azides as versatile synthetic precursors or transient intermediates for compounds of synthetic and biological significance under visible light photocatalysis. We have classified this review into two parts: (i) formation of an iminyl radical intermediate and (ii) formation of 2H-azirine intermediate-based reactions.

Electromotive Drug Administration in the Ureter in an In Vivo Animal Model: Initial Report.

Introduction: Electromotive drug administration (EMDA) delivers a drug deeply into targeted tissues, such as the bladder. EMDA has never been applied to the ureter. Methods: In four in vivo porcine ureters, a unique EMDA catheter containing a silver conducting wire was advanced for the infusion of methylene blue. In two ureters, a pulsed current was delivered through an EMDA machine, whereas the other two ureters served as a control. After 20 minutes of infusion, the ureters were harvested. Results: In the EMDA ureter, there was diffuse staining of the urothelium; penetration of methylene blue occurred in the lamina propria and muscularis propria. In the control ureter, there was only patchy staining of the urothelium. Conclusion: In this first report of ureteral EMDA, a charged molecule penetrated beyond the urothelium into the lamina propria and muscularis propria of the porcine ureter.

Effect of Hypoalbuminemia in Patients Undergoing Parathyroidectomy for Primary Hyperparathyroidism.

OBJECTIVES: Treatment for primary hyperparathyroidism is parathyroidectomy. This study identifies the association between hypoalbuminemia (HA) and outcomes in patients undergoing parathyroidectomy for primary hyperparathyroidism. METHODS: This retrospective cohort analysis utilized the 2006-2015 National Surgical Quality Improvement Program database. Current Procedure Terminology codes were used to identify patients undergoing parathyroidectomy for primary hyperparathyroidism. Prolonged length of stay (LOS) was defined as a duration of 2 days or greater. Demographics and comorbidities were compared between HA (serum albumin <3.5 g/dL) and non-HA cohorts using chi-square analysis. The independent effect of HA on adverse outcomes was analyzed using binary logistic regression. RESULTS: A total of 7183 cases with primary hyperparathyroidism were classified into HA (n = 381) and non-HA (n = 6802) cohorts. HA patients had increased complications, including renal insufficiency (0.8% vs. 0.0%, p = 0.001), sepsis (1.0% vs. 0.1%, p = 0.003), pneumonia (0.8% vs. 0.1%, p = 0.018), acute renal failure (1.0% vs. 0.0%, p < 0.001), and unplanned intubation (1.3% vs. 0.2%, p = 0.004). HA patients had increased risk of death (1.6% vs. 0.1%, p < 0.001), prolonged LOS (40.9% vs. 6.3%, p < 0.001), and any complication (5.5% vs. 1.2%, p < 0.001). Adjusted binary logistic regression indicated HA patients experienced increased odds of progressive renal insufficiency (OR 18.396, 95% CI 1.844-183.571, p = 0.013), prolonged LOS (OR 4.892; 95% CI 3.571-6.703; p < 0.001), unplanned reoperation (OR 2.472; 95% CI 1.012-6.035; p = 0.047), and unplanned readmission (OR 3.541; 95% CI 1.858-6.748; p < 0.001). CONCLUSIONS: HA may be associated with adverse complications in patients undergoing parathyroidectomy for primary hyperparathyroidism. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:2035-2039, 2023.

Evaluation of the portability of computable phenotypes with natural language processing in the eMERGE network.

The electronic Medical Records and Genomics (eMERGE) Network assessed the feasibility of deploying portable phenotype rule-based algorithms with natural language processing (NLP) components added to improve performance of existing algorithms using electronic health records (EHRs). Based on scientific merit and predicted difficulty, eMERGE selected six existing phenotypes to enhance with NLP. We assessed performance, portability, and ease of use. We summarized lessons learned by: (1) challenges; (2) best practices to address challenges based on existing evidence and/or eMERGE experience; and (3) opportunities for future research. Adding NLP resulted in improved, or the same, precision and/or recall for all but one algorithm. Portability, phenotyping workflow/process, and technology were major themes. With NLP, development and validation took longer. Besides portability of NLP technology and algorithm replicability, factors to ensure success include privacy protection, technical infrastructure setup, intellectual property agreement, and efficient communication. Workflow improvements can improve communication and reduce implementation time. NLP performance varied mainly due to clinical document heterogeneity; therefore, we suggest using semi-structured notes, comprehensive documentation, and customization options. NLP portability is possible with improved phenotype algorithm performance, but careful planning and architecture of the algorithms is essential to support local customizations.

Comparison of Superpulse Thulium Fiber Laser vs Holmium Laser for Ablation of Renal Calculi in an In Vivo Porcine Model.

Introduction and Objectives: We sought to compare the effectiveness and efficiency of the superpulse thulium fiber laser (sTFL to the holmium: yttrium-aluminum-garnet [Ho:YAG] laser for ureteroscopic "dusting" of implanted renal stones in an in vivo porcine model. Methods: Twenty-four porcine kidneys (12 juvenile female Yorkshire pigs) were randomized to Ho:YAG or sTFL treatment groups. Canine calcium oxalate stones were scanned with computed tomography to calculate stone volume and stone density; the stones were randomized and implanted into each renal pelvis via an open pyelotomy. In all trials, a 14F, 35 cm ureteral access sheath was placed. With a 9.9F dual lumen flexible ureteroscope, laser lithotripsy was performed using dusting settings: Ho:YAG 200 µm laser fiber at 16 W (0.4 J, 40 Hz) or sTFL 200 µm laser fiber at 16 W (0.2 J, 80 Hz). Lithotripsy continued until no fragments over 1 mm were observed. No stone basketing was performed. Throughout the procedures, intrarenal and renal pelvis temperatures were measured using two percutaneously positioned K-type thermocouples, one in the upper pole calyx and one in the renal pelvis. After the lithotripsy, the ureteropelvic junction was occluded, the kidneys were bivalved, and all residual fragments were collected, dried, weighed, and then measured with an optical laser particle sizer. Results: Implanted stones were similar in volume and density in both groups. Intraoperative collecting system temperatures were similar for both groups (all <44°C). Compared to Ho:YAG, sTFL ablated stones faster (9 vs 27 minutes, p < 0.001) with less energy expenditure (8 vs 26 kJ, p < 0.001), and a greater stone clearance rate (73% vs 45%, p = 0.001). After sTFL lithotripsy, 77% of the remaining fragments were ≤1 mm vs 17% of fragments ≤1 mm after Ho:YAG treatment (p < 0.001). Conclusions: In an in vivo porcine kidney, using dusting settings, sTFL lithotripsy resulted in shorter ablation times, higher stone clearance rates, and markedly smaller stone fragments than Ho:YAG lithotripsy.