Work absence and productivity loss of patients undergoing a trial of spontaneous passage for ureteral stones.

Patients with ureteral stones are often managed with a spontaneous trial of passage. While cost effective, the current literature has not examined the effects of a trial of passage on patients' work productivity. In this study, we aim to characterize work absence and productivity losses in a cohort of patients undergoing a trial of passage for ureteral stones. Actively employed patients aged 18 to 64 and discharged from Duke emergency departments without surgical intervention for ureteral stones ≤ 10 mm were contacted by phone four weeks after their presentation. Participants completed the Institute for Medical Technology Assessment Productivity Cost Questionnaire which assesses three domains: absenteeism - missed work; presenteeism -productivity when returning to work; and unpaid work - assistance with household work. Linear regression associated demographic and stone factors with productivity losses.109 patients completed the survey. In total, 67% of patients missed work, 46% had decreased productivity when returning to work, and 55% required assistance with unpaid work. 59% of patients with stones ≤ 5 mm missed work versus 84% with stones > 5 mm (p = 0.009). African American race (coefficient 23.68, 95% confidence interval 2.24-45.11, p = 0.031), first-time stone formers (coefficient 20.28, 95% confidence interval 2.50-38.07, p = 0.026), and patients with stones > 5 mm (coefficient 25.34, 95% CI 5.25-45.44, p = 0.014) were associated with increased productivity losses. The majority of patients miss work while undergoing a trial of passage and many have decreased productivity when returning to work. This information may help counsel patients in emergency departments, especially first-time stone formers, and prevent return visits.

Three-dimensional super-resolution passive cavitation mapping in laser lithotripsy.

Kidney stone disease is a major public health issue. By breaking stones with repeated laser irradiation, laser lithotripsy (LL) has become the main treatment for kidney stone disease. Laser-induced cavitation is closely associated with the stone damage in LL. Monitoring the cavitation activities during LL is thus crucial to optimizing the stone damage and maximizing LL efficiency. In this study, we have developed three-dimensional super-resolution passive cavitation mapping (3D-SRPCM), in which the cavitation bubble positions can be localized with an accuracy of 40 µm, which is 1/10th of the acoustic diffraction limit. Moreover, the 3D-SRPCM reconstruction speed has been improved by 300 times by adopting a GPU-based sparse-matrix beamforming approach. Using 3D-SRPCM, we studied LL-induced cavitation activities on BegoStones, both in free space of water and confined space of a kidney phantom. The dose-dependence analysis provided by 3D-SRPCM revealed that accumulated impact pressure on the stone surface has the highest correlation with the stone damage. By providing high-resolution cavitation mapping during LL treatment, we expect that 3D-SRPCM may become a powerful tool to improve the clinical LL efficiency and patient outcome.

The Impact of Single-Use Cystoscopes on Clinical Time Workflow in an Outpatient Setting.

OBJECTIVE: To evaluate the change in overall clinical encounter time and clinical capacity after transitioning to single-use cystoscopes (Ambu A/S, Ballerup, Denmark) in an outpatient urology setting. METHODS: A single-institution prospective study in an outpatient urology procedure clinic was performed. Discrete categories for each portion of nursing care responsibilities were defined, and time spent during each category was recorded. Two separate clinic days were observed and analyzed: one where the clinic exclusively used reusable cystoscopes and the other after the transition to single-use cystoscopes occurred. Additionally, clinic schedules were reviewed from all procedure clinics in the 3-month periods before and after the transition to single-use cystoscopes. Outcomes included overall clinical encounter time and the number of procedures per clinic day. RESULTS: There were 12 flexible cystoscopies performed during each of the observed clinic days. Preliminary cystoscope cleaning and transportation tasks by nursing staff were eliminated when utilizing single-use cystoscopes. Average total encounter time decreased from 66 to 44 minutes, resulting in a 34% reduction in clinical encounter time. The median number of flexible cystoscopy procedures increased after the transition from 9 (IQR 7-12) to 16 (IQR 11-17), representing a 78% increase (P = .003). CONCLUSION: Transition to a completely single-use cystoscopy outpatient procedure clinic improved clinical efficiency and facilitated an increased number of procedures per clinic day.

Translating ethical and quality principles for the effective, safe and fair development, deployment and use of artificial intelligence technologies in healthcare.

OBJECTIVE: The complexity and rapid pace of development of algorithmic technologies pose challenges for their regulation and oversight in healthcare settings. We sought to improve our institution's approach to evaluation and governance of algorithmic technologies used in clinical care and operations by creating an Implementation Guide that standardizes evaluation criteria so that local oversight is performed in an objective fashion. MATERIALS AND METHODS: Building on a framework that applies key ethical and quality principles (clinical value and safety, fairness and equity, usability and adoption, transparency and accountability, and regulatory compliance), we created concrete guidelines for evaluating algorithmic technologies at our institution. RESULTS: An Implementation Guide articulates evaluation criteria used during review of algorithmic technologies and details what evidence supports the implementation of ethical and quality principles for trustworthy health AI. Application of the processes described in the Implementation Guide can lead to algorithms that are safer as well as more effective, fair, and equitable upon implementation, as illustrated through 4 examples of technologies at different phases of the algorithmic lifecycle that underwent evaluation at our academic medical center. DISCUSSION: By providing clear descriptions/definitions of evaluation criteria and embedding them within standardized processes, we streamlined oversight processes and educated communities using and developing algorithmic technologies within our institution. CONCLUSIONS: We developed a scalable, adaptable framework for translating principles into evaluation criteria and specific requirements that support trustworthy implementation of algorithmic technologies in patient care and healthcare operations.

Exploring optimal settings for safe and effective thulium fibre laser lithotripsy in a kidney model.

OBJECTIVES: To explore the optimal laser settings and treatment strategies for thulium fibre laser (TFL) lithotripsy, namely, those with the highest treatment efficiency, lowest thermal injury risk, and shortest procedure time. MATERIALS AND METHODS: An in vitro kidney model was used to assess the efficacy of TFL lithotripsy in the upper calyx. Stone ablation experiments were performed on BegoStone phantoms at different combinations of pulse energy (EP ) and frequency (F) to determine the optimal settings. Temperature changes and thermal injury risks were monitored using embedded thermocouples. Experiments were also performed on calcium oxalate monohydrate (COM) stones to validate the optimal settings. RESULTS: High EP /low F settings demonstrated superior treatment efficiency compared to low EP /high F settings using the same power. Specifically, 0.8 J/12 Hz was the optimal setting, resulting in a twofold increase in treatment efficiency, a 39% reduction in energy expenditure per unit of ablated stone mass, a 35% reduction in residual fragments, and a 36% reduction in total procedure time compared to the 0.2 J/50 Hz setting for COM stones. Thermal injury risk assessment indicated that 10 W power settings with high EP /low F combinations remained below the threshold for tissue injury, while higher power settings (>10 W) consistently exceeded the safety threshold. CONCLUSIONS: Our findings suggest that high EP /low F settings, such as 0.8 J/12 Hz, are optimal for TFL lithotripsy in the treatment of COM stones. These settings demonstrated significantly improved treatment efficiency with reduced residual fragments compared to conventional settings while keeping the thermal dose below the injury threshold. This study highlights the importance of using the high EP /low F combination with low power settings, which maximizes treatment efficiency and minimizes potential thermal injury. Further studies are warranted to determine the optimal settings for TFL for treating kidney stones with different compositions.

In vitro investigation of stone ablation efficiency, char formation, spark generation, and damage mechanism produced by thulium fiber laser.

To investigate stone ablation characteristics of thulium fiber laser (TFL), BegoStone phantoms were spot-treated in water at various fiber tip-to-stone standoff distances (SDs, 0.5 ~ 2 mm) over a broad range of pulse energy (Ep, 0.2 ~ 2 J), frequency (F, 5 ~ 150 Hz), and power (P, 10 ~ 30 W) settings. In general, the ablation speed (mm3/s) in BegoStone decreased with SD and increased with Ep, reaching a peak around 0.8 ~ 1.0 J. Additional experiments with calcium phosphate (CaP), uric acid (UA), and calcium oxalate monohydrate (COM) stones were conducted under two distinctly different settings: 0.2 J/100 Hz and 0.8 J/12 Hz. The concomitant bubble dynamics, spark generation and pressure transients were analyzed. Higher ablation speeds were consistently produced at 0.8 J/12 Hz than at 0.2 J/100 Hz, with CaP stones most difficult yet COM and UA stones easier to ablate. Charring was mostly observed in CaP stones at 0.2 J/100 Hz, accompanied by strong spark-generation, explosive combustion, and diminished pressure transients, but not at 0.8 J/12 Hz. By treating stones in parallel fiber orientation and leveraging the proximity effect of a ureteroscope, the contribution of bubble collapse to stone ablation was found to be substantial (16% ~ 59%) at 0.8 J/12 Hz, but not at 0.2 J/100 Hz. Overall, TFL ablation efficiency is significantly better at high Ep/low F setting, attributable to increased cavitation damage with less char formation.

Rural For-Profit Hospitals Are Associated With Higher Commercial Prices for 3 Common Urological Procedures.

INTRODUCTION: Rural patients lack access to urological services, and high local prices may dissuade underinsured patients from surgery. We sought to describe commercially insured prices for 3 urological procedures at rural vs metropolitan and for-profit vs nonprofit hospitals. METHODS: A cross-sectional analysis of commercially insured prices from the Turquoise Health Transparency data set was performed for ureteroscopy with laser lithotripsy, transurethral resection of bladder tumor, and transurethral resection of prostate. Hospital characteristics were linked using the Centers for Medicare and Medicaid Services Healthcare Cost Reporting Information System. Linear modeling analyzed median hospital price and its association with hospital characteristics. RESULTS: Overall, 1,532 hospitals reported urological prices in Turquoise. Median prices for each procedure were higher at rural for-profits (ureteroscopy $16,522, transurethral resection of bladder tumor $5,393, transurethral resection of prostate $9,999) vs rural nonprofits (ureteroscopy $4,512, transurethral resection of bladder tumor $2,788, transurethral resection of prostate $3,881) and metropolitan for-profits (ureteroscopy $5,411, transurethral resection of bladder tumor $3,420, transurethral resection of prostate $4,874). Rural for-profit status was independently associated with 160% higher price for ureteroscopy (relative cost ratio 2.60, P < .001), 50% higher for transurethral resection of bladder tumor (relative cost ratio 1.50, P = .002), and 113% higher for transurethral resection of prostate (relative cost ratio 2.13, P < .001). CONCLUSIONS: Prices are higher for 3 common urological surgeries at rural for-profit hospitals. Differential pricing may contribute to disparities for underinsured rural residents who lack access to nonprofit facilities. Interventions that facilitate transportation and price shopping may improve access to affordable urological care.

In Pursuit of the Optimal Dusting Settings with the Thulium Fiber Laser: An In Vitro Assessment.

Objective: Low energy and high frequency settings are used in stone dusting for holmium lasers. Such settings may not be optimal for thulium fiber laser (TFL). With the seemingly endless combination of settings, we aim to provide guidance to the practicing urologists and assess the efficiency of the TFL platform in an automated in vitro "dusting model." Materials/Methods: Three experimental setups were designed to investigate stone dusting produced by an IPG Photonics TLR-50 W TFL system using 200 µm fiber and soft BegoStone phantoms. The most popular 10 and 20 W dusting settings among endourologist familiar with TFL were evaluated. We directly compared short pulse (SP) vs long pulse (LP) mode using various combinations of pulse energy (Ep) and pulse frequency (F). Thereafter, we tested the 10 and 20 W settings and compared them among each other to elucidate the most efficient settings at each power. Treatments were performed under the same total laser energy delivered to the stone at four different standoff distances (SDs) with a clinically relevant scanning speed of either 1 or 2 mm/sec. Ablation volumes were quantified by optical coherence tomography to assess stone dusting efficiency. Fragment size after ablation at different pulse energies was evaluated by sieving and evaluating under a microscope after treatment. Results: Overall, SP provided greater ablation volume when compared with LP. Our dusting efficiency model demonstrated that the maximum stone ablation was achieved at the combination of high energy/low frequency settings (p < 0.005) and at a SD of 0.2 mm. At all tested pulse energies, no stone phantoms were broken into fragments >1 mm. Conclusions: During stone dusting with TFL, SP offers superior ablation to LP settings. Optimal dusting at clinically relevant scanning speeds of 1 and 2 mm/sec occurs at high energy/low frequency settings. Thulium lithotripsy with high Ep does not result in increased fragment size.

Association of Rural Hospital for-Profit Status With Higher Publicly Reported Prices for the Components of Inpatient Hematuria Evaluation Among Commercially Insured Patients.

INTRODUCTION: Rural patients have limited access to urological care and are vulnerable to high local prices. Little is known about price variation for urological conditions. We aimed to compare reported commercial prices for the components of inpatient hematuria evaluation between for-profit vs not-for-profit and rural vs metropolitan hospitals. METHODS: We abstracted commercial prices for the components of intermediate- and high-risk hematuria evaluation from a price transparency data set. We compared hospital characteristics between those that do and do not report prices for a hematuria evaluation using the Centers for Medicare and Medicaid Services Healthcare Cost Reporting Information System. Generalized linear modelling evaluated the association between hospital ownership and rural/metropolitan status with prices of intermediate- and high-risk evaluations. RESULTS: Of all hospitals, 17% of for-profits and 22% of not-for-profits report prices for hematuria evaluation. For intermediate-risk, median price at rural for-profit hospitals was $6,393 (interquartile range [IQR] $2,357-$9,295) compared to $1,482 (IQR $906-$2,348) at rural not-for-profits and $2,645 (IQR $1,491-$4,863) at metropolitan for-profits. For high-risk, rural for-profit hospitals' median price was $11,151 (IQR $5,826-$14,366) vs $3,431 (IQR $2,474-$5,156) at rural not-for-profits and $4,188 (IQR $1,973-$8,663) at metropolitan for-profits. Rural for-profit status was associated with an additional higher price for intermediate- (relative cost ratio 1.62, 95% CI 1.16-2.28, P = .005) and high-risk evaluations (relative cost ratio 1.50, 95% CI 1.15-1.97, P = .003). CONCLUSIONS: Rural for-profit hospitals report high prices for components of inpatient hematuria evaluation. Patients should be aware of prices at these facilities. These differences may dissuade patients from undergoing evaluation and lead to disparities.

Advanced chronic kidney disease; A comparison between nephroureterectomy and nephron-sparing surgery for upper tract urothelial carcinoma.

PURPOSE: Renal function outcomes between radical nephroureterectomy (RNU) and nephron-sparing surgery (NSS) for upper tract urothelial carcinoma (UTUC) patients are not well established. We sought to compare the incidence and factors associated with development of advanced chronic kidney disease (CKD) between RNU and NSS and examine the role of acute kidney injury (AKI) on renal function outcomes. METHODS: We retrospectively analyzed an institutional database for patients who underwent either RNU or NSS for UTUC. Cumulative incidence of postoperative advanced CKD, defined as eGFR < 30 ml/min/1.73 m2, was compared between groups. Fine-Gray competing risk regression was used to identify predictors of advanced CKD. Locally weight scatterplot smoothing was used to assess postoperative eGFR trends. AKI events were counted, staged, and assessed for influence of progression to advanced CKD. RESULTS: Four hundred and twenty-six patients were included in analysis, with a median follow up of 6.68 years (IQR 3.4-12.2). Median preoperative eGFR was similar between the groups (NSS: 68 ml/min/1.73 m2, RNU: 65 ml/min/1.73 m2,P = 0.220). Cumulative incidence of advanced CKD was significantly lower in the NSS cohort (P = 0.009). Factors associated with advanced CKD included age, diabetes, recurrent AKI and RNU. Percent of patients with an AKI event differed between the groups (51.5% NSS, 72.7% RNU, P = <0.001), there was no between group difference in percentage of patients with recurrent AKI (25.6% NSS, 25.9% RNU, P =1). CONCLUSION: NSS provides a renal function benefit in UTUC. AKI is common among UTUC patients and recurrent AKI is a risk factor for development of advanced CKD.

Benchtop Evaluation of Miniature Percutaneous Nephrolithotomy Lithotrites.

Introduction: Percutaneous nephrolithotomy (PCNL) is the preferred treatment for kidney stones >2 cm. While PCNL has traditionally been performed using 24F to 30F access sheaths, there is a trend toward smaller sheaths and scopes to perform mini-PCNL (mPCNL). We performed benchtop assessment of multiple mPCNL lithotrites. Methods: One 1 cm3, hard Begostone phantom was placed in a cylinder with four 5.5 mm cylindrical openings to simulate the size of a 16.5F mPCNL sheath. Lithotripsy was performed with the 1.5 and 1.9 mm Trilogy, 1.83 mm ShockPulse, or a 200 µm Holmium:YAG (Ho:YAG) laser. Suction was used for the mechanical lithotrites. The Trilogy probes were set at 50% impact, 6 Hz, 80% ultrasound and 10% suction. The ShockPulse was used at high-power setting with low suction. The 1.9 mm Trilogy probe was used with a 15F mini-nephroscope. The 1.83 mm ShockPulse, 1.5 mm Trilogy and laser fiber were used with a 12F mini-nephroscope. The 120 W holmium laser was set at 0.5 J/70 Hz Moses-Distance. Ten independent runs were performed with modality. Time to complete stone clearance was recorded and mass stone clearance rates were calculated. Results: The Trilogy 1.9 mm showed superior stone clearance rate (11.69 ± 3.68 mg/s) vs the ShockPulse (SP) 1.83 mm (6.29 ± 1.37 mg/s, p = 0.003), the laser fiber (4.73 ± 0.61 mg/s, p < 0.0005), and the Trilogy 1.5 mm (6.84 ± 1.21 mg/s). The 200 µm laser fiber was inferior to all mechanical lithotrites. There was no difference between the 1.5 mm Trilogy and the 1.83 mm ShockPulse (p = 0.772). This translates to 3.9, 4.8, and 8.1 minutes less treatment time vs the 1.5 mm Trilogy, SP, and laser, respectively, for a spherical 1.5 cm diameter calcium oxalate monohydrate stone. Conclusion: Among these four commonly used mPCNL lithotripters, the Trilogy 1.9 mm demonstrated superior stone clearance rates in this benchtop model vs the Ho:YAG laser, 1.83 mm SP, and Trilogy 1.5 mm. Future clinical testing is warranted to evaluate the optimal lithotrite for mPCNL.

Investigating Risk Factors for Urine Culture Contamination in Outpatient Clinics: A New Avenue for Diagnostic Stewardship.

Mixed flora in urine cultures usually occur due to pre-analytic contamination. In our outpatient urology clinic, we found a high prevalence of mixed flora (46.2%), which was associated with female sex and older age. Patient education did not impact the rate of mixed flora. Future efforts should target high-risk patients.

Cavitation Plays a Vital Role in Stone Dusting During Short Pulse Holmium:YAG Laser Lithotripsy.

Objective: To investigate the mechanism of stone dusting in Holmium (Ho): YAG laser lithotripsy (LL). Materials and Methods: Cylindrical BegoStone samples (6 × 6 mm, H × D) were treated in water using a clinical Ho:YAG laser lithotripter in dusting mode (0.2-0.4 J with 70-78 µs in pulse duration, 20 Hz) at various fiber tip to stone standoff distances (SD = 0, 0.5, and 1 mm). Stone damage craters were quantified by optical coherence tomography and bubble dynamics were captured by high-speed video imaging. To differentiate the contribution of cavitation vs thermal ablation to stone damage, three additional experiments were performed. First, presoaked wet stones were treated in air to assess stone damage without cavitation. Second, the laser fiber was advanced at various offset distances (OSD = 0.25, 1, 2, 3, and 10 mm) from the tip of a flexible ureteroscope to alter the dynamics of bubble collapse. Third, stones were treated with parallel fiber to minimize photothermal damage while isolating the contribution of cavitation to stone damage. Results: Treatment in water resulted in 2.5- to 90-fold increase in stone damage compared with those produced in air where thermal ablation dominates. With the fiber tip placed at OSD = 0.25 mm, the collapse of the bubble was distracted away from the stone surface by the ureteroscope tip, leading to significantly reduced stone damage compared with treatment without the scope or with scope at large OSD of 3-10 mm. The average crater volume produced by parallel fiber orientation at 0.2 J after 100 pulses, where cavitation is the dominant mechanism of stone damage, was comparable with those produced by using perpendicular fiber orientation within SD = 0.25-1 mm. Conclusion: Cavitation plays a dominant role over photothermal ablation in stone dusting during short pulse Ho:YAG LL when 10 or more pulses are delivered to the same location.

Evolution of Single-Use Urologic Endoscopy: Benchtop and Initial Clinical Assessment of a New Single-Use Flexible Cystoscope.

Introduction: Office cystoscopy is one of the most frequently performed procedures by a urologist. However, single-use cystoscopes remain quite undeveloped. Ambu® has developed single-use broncoscopes, rhinolaryngoscopes, and duodenoscopes. Recently, they released a single-use cystoscope. In this study, we performed a benchtop and an initial clinical assessment of the Ambu aScope™ (4) Cysto (aS4C) single-use cystoscope. Materials and Methods: Ten new, never-used aS4C single-use cystoscopes were assessed for optical performance, maximal tip flexion, and irrigation flow rate with empty working channel, 365 µm laser fiber, 0.035 in hydrophilic-tipped wire, 1.9F nitinol basket, and a 1.8 mm flexible stent grasper. All cystoscopes were then fully flexed 25 times in each direction, and maximal flexion angles were remeasured with and without instruments. Optical resolution, distortion, and depth of field were measured and compared with our reusable digital flexible cystoscopes. Assessment of clinical use was performed for inpatient bedside procedures using a Likert feedback survey and the NASA Task Load Index. Results: Maximal upward flexion exceeded 200° and 160° for all working instruments in upward and downward flexion. Downward flexion demonstrated different flexion between instrument groups in pre- and postcycling (p < 0.001). There was no clinical difference between the pre- and postcycling flexion. Flow rate decreased with increasing working instrument size (p < 0.001). The Olympus HD cystoscope resolution was superior at 3 and 5 mm distance, but not at other distances. The Ambu scope was superior to the Olympus SD scope at all distances except 3 mm. The aS4C had higher Likert scale survey scores for clinical use. Conclusions: The new Ambu single-use cystoscope demonstrates good flexion across instruments and comparable optics with reusable cystoscopes. In addition, initial inpatient bedside use of the aS4C and Monitor system compares favorably with the Olympus reusable cystoscope. Further testing in clinical scenarios such as hematuria, urothelial carcinoma, and operative endoscopy is warranted.

Comparison of Different Pulse Modulation Modes for Holmium:Yttrium-Aluminum-Garnet Laser Lithotripsy Ablation in a Benchtop Model.

Introduction: Manipulation of Holmium:Yttrium-Aluminum-Garnet laser parameters such as pulse energy (PE), frequency, and duration can impact laser lithotripsy ablation efficiency. In 2017, Lumenis introduced Moses™ Technology, which uses pulse modulation to enhance the delivery of energy from fiber to stone as well as to minimize stone retropulsion. Since the introduction of Moses Technology, other companies have brought additional pulse modulation concepts to market. The purpose of this in vitro study is to compare the pulse characteristics and stone ablation efficiency of Lumenis Moses Technology with Quanta's Vapor Tunnel™. Materials and Methods: Submerged BegoStone phantoms were systematically ablated using either the Lumenis Moses Pulse 120H or the Quanta Litho 100 clinical laser system. Two PEs (0.4 and 1 J), three fiber-stone standoff distances (SDs) (0.5, 1, 2 mm), and all available pulse duration and modulation modes for each laser were tested in combination. Fiber speed was adjusted to scan across the stone surface at either 1 or 10 pulses/mm to form single pulse craters or an ablation trough, respectively. Volumes of single craters and 1 mm trough segments were imaged and quantified using optical coherence tomography. Results: Ablation volumes decreased with decreasing PE and increasing SD. Statistically significant variability was seen between pulse types (PT) at every tested parameter set. Among pulse modulation modes, Moses Distance (MD) was superior at 0.5 mm in all testing and at 2 mm in trough testing. Vapor Tunnel (VT) was superior in 2 mm single crater testing. All modulated pulses performed similarly at 1 mm. Conclusions: In this benchtop model of laser lithotripsy, stone ablation was significantly impacted by PT. MD demonstrated superior or noninferior stone ablation at most tested parameters. VT maintained its efficacy the best as SD increased. Future work should focus on the mechanistic differences of these modes relative to other traditional laser pulse modes.

The Role of Cavitation in Energy Delivery and Stone Damage During Laser Lithotripsy.

Purpose: Although cavitation during laser lithotripsy (LL) contributes to the Moses effect, the impact of cavitation on stone damage is less clear. Using different laser settings, we investigate the role of cavitation bubbles in energy delivery and stone damage. Materials and Methods: The role of cavitation in laser energy delivery was characterized by using photodetector measurements synced with high-speed imaging for laser pulses of varying durations. BegoStone samples were treated with the laser fiber oriented perpendicularly in contact with the stone in water or in air to assess the impact of cavitation on crater formation. Crater volume and geometry were quantified by using optical coherence tomography. Further, the role of cavitation in stone damage was elucidated by treatment in water with the fiber oriented parallel to the stone surface and by photoelastic imaging. Results: Longer pulse durations resulted in higher energy delivery but smaller craters. Stones treated in water resulted in greater volume, wider yet shallower craters compared with those treated in air. Stones treated with the parallel fiber showed crater formation after 15 pulses, confirmed by high-speed imaging of the bubble collapse with the resultant stress field captured by photoelastic imaging. Conclusions: Despite improved energy delivery, the longer pulse mode produced smaller crater volume, suggesting additional processes secondary to photothermal ablation are involved in stone damage. Our critical observations of the difference in stone damage treated in water vs in air, combined with the crater formation by parallel fiber, suggest that cavitation is a contributor to stone damage during LL.