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PURPOSE: Our goal was to test transcutaneous focused ultrasound in the form of ultrasonic propulsion and burst wave lithotripsy to reposition ureteral stones and facilitate passage in awake subjects. MATERIALS AND METHODS: Adult subjects with a diagnosed proximal or distal ureteral stone were prospectively recruited. Ultrasonic propulsion alone or with burst wave lithotripsy was administered by a handheld transducer to awake, unanesthetized subjects. Efficacy outcomes included stone motion, stone passage, and pain relief. Safety outcome was the reporting of associated anticipated or adverse events. RESULTS: Twenty-nine subjects received either ultrasonic propulsion alone (n = 16) or with burst wave lithotripsy bursts (n = 13), and stone motion was observed in 19 (66%). The stone passed in 18 (86%) of the 21 distal ureteral stone cases with at least 2 weeks follow-up in an average of 3.9±4.9 days post-procedure. Fragmentation was observed in 7 of the burst wave lithotripsy cases. All subjects tolerated the procedure with average pain scores (0–10) dropping from 2.1±2.3 to 1.6±2.0 (P = .03). Anticipated events were limited to hematuria on initial urination post-procedure and mild pain. In total, 7 subjects had associated discomfort with only 2.2% (18 of 820) propulsion bursts. CONCLUSIONS: This study supports the efficacy and safety of using ultrasonic propulsion and burst wave lithotripsy in awake subjects to reposition and break ureteral stones to relieve pain and facilitate passage.

Renal colic encounters are common; in the United States alone, they represent greater than one million annual emergency department (ED) visits. Most of these stones are managed conservatively with a trial of passage. However, some lead to repeat colic episodes, secondary ED visits, increased anxiety, and increased cost. Of the 5%–10% of symptomatic stones that become lodged at the ureteropelvic junction and are larger than 5 mm, most require operative intervention. In the process of executing a NASA‐funded study of ultrasonic repositioning of kidney stones, the subject was administered fluid to dilate the collecting system, placed in Trendelenburg bed positioning, and rolled to both sides. During this process a symptomatic, obstructing 9‐mm ureteropelvic junction stone moved back into the kidney's lower pole/infundibulum and symptoms were immediately resolved. The patient remained asymptomatic for a period of 5 weeks at which point elective intervention was scheduled. This case demonstrates that ureteropelvic junction stones may be repositioned in a non‐invasive manner, turning a stone that requires urgent intervention into one that can be managed electively.

INTRODUCTION AND OBJECTIVE:The feasibility of ultrasonic propulsion and burst wave lithotripsy (BWL) to noninvasively reposition distal ureteral stones to facilitate passage and relieve pain was te...

Purpose: Ultrasonic propulsion is an investigative modality to noninvasively image and reposition urinary stones. Our goals were to test safety and effectiveness of new acoustic exposure conditions from a new transducer, and to use simultaneous ureteroscopic and ultrasonic observation to quantify stone repositioning. Materials and Methods: During operation, ultrasonic propulsion was applied transcutaneously, whereas stone targets were visualized ureteroscopically. Exposures were 350 kHz frequency, ≤200 W/cm(2) focal intensity, and ≤3-second bursts per push. Ureteroscope and ultrasound (US) videos were recorded. Video clips with and without stone motion were randomized and scored for motion ≥3 mm by independent reviewers blinded to the exposures. Subjects were followed with telephone calls, imaging, and chart review for adverse events. Results: The investigative treatment was used in 18 subjects and 19 kidneys. A total of 62 stone targets were treated ranging in size from a collection of “dust” to 15 mm. Subjects received an average of 17 ± 14 propulsion bursts (per kidney) for a total average exposure time of 40 ± 40 seconds. Independent reviewers scored at least one stone movement ≥3 mm in 18 of 19 kidneys (95%) from the ureteroscope videos and in 15 of 19 kidneys (79%) from the US videos. This difference was probably because of motion out of the US imaging plane. Treatment repositioned stones in two cases that would have otherwise required basket repositioning. No serious adverse events were observed with the device or procedure. Conclusions: Ultrasonic propulsion was shown to be safe, and it effectively repositioned stones in 95% of kidneys despite positioning and access restrictions caused by working in an operating room on anesthetized subjects.

INTRODUCTION: A considerable publication record exists comparing sensitivity and specificity of radiological ultrasound (including point of care ultrasound) to computerized tomography for stone disease. However, the practical application of in-office ultrasound to support the growing number of kidney stone centers around the world represents a nuanced topic that is ripe for study and discussion. METHODS: We provide a descriptive analysis of how in-office ultrasound is being used as an adjunct to clinical care based on our experience during 50 days in clinic at an institutionally affiliated, multidisciplinary kidney stone center. Clinic subjects gave consent and underwent ultrasound as part of research studies. Ultrasonograms were shared with and verified by the treating physician before the patient was discharged from care. We counted the number of times research imaging altered the care plan. RESULTS: Of the 60 patients enrolled the clinician used the information obtained from the studies in 20 (33%) to determine the course of clinical care that resulted in a change in treatment or process. CONCLUSIONS: Ultrasound has the potential to be a cost-effective and valuable tool that can provide more efficient workflow within a kidney stone center or urology clinic.

OBJECTIVE To determine if obtaining a 24-hour urine collection (24HU) in stone formers is associated with decreased recurrent stone episodes. METHODS Using the MarketScan database, adults 17-62 years old with nephrolithiasis were identified between 2007 and 2017 with a minimum of 3-year follow up. High-risk stone formers, those undergoing stone surgery, and those with history of recurrent stones were identified. The exposure was a 24HU within 6 months of primary diagnosis. The outcome was recurrent stone episodes—defined by stone-related emergency room visits, hospitalizations, or stone surgery 90 days to 3 years after diagnosis. Logistic regression was used to estimate recurrence risk by 24HU exposure for the overall cohort and sub-cohorts limited to known recurrent stone formers, high-risk subjects, and those having stone surgery. RESULTS Of 434,055 subjects analyzed, 30,153 (6.9%) had a 24HU. An annual decline in 24HU utilization was seen (7.5%-5.8%). Regional variation in usage rate was also observed. On multivariate analysis, completing a 24HU was not associated with risk of recurrence in any of the following cohorts: recurrent stone formers (OR 0.98, 95% CI 0.9-1.07), both high risk and recurrent stone formers (OR 0.95 [0.8-1.13]), those undergoing surgery (OR 1.02 [0.97-1.07]); a positive association with 24HU and recurrence was seen in those labeled high-risk (OR 1.08 [1.01-1.16]) and in all-comers (OR 1.15 [1.12-1.19]). CONCLUSION The 24HU was not associated with decreased recurrence rates in the overall population nor in higher risk sub-cohorts.

Purpose of review Burst wave lithotripsy and ultrasonic propulsion of kidney stones are novel, noninvasive emerging technologies to separately or synergistically fragment and reposition stones in an office setting. The purpose of this review is to discuss the latest refinements in technology, to update on testing of safety and efficacy, and to review future applications. Recent findings Burst wave lithotripsy produced consistent, small passable fragments through transcutaneous applications in a porcine model, while producing minimal injury and clinical trials are now underway. A more efficient ultrasonic propulsion design that can also deliver burst wave lithotripsy effectively repositioned 95% of stones in 18 human participants (18 of 19 kidneys) and clinical trials continue. Acoustic tractor beam technology is an emerging technology with promising clinical applications through the manipulation of macroscopic objects. Summary The goal of the reviewed work is an office-based system to image, fragment, and reposition urinary stones to facilitate their natural passage. The review highlights progress in establishing safety, effectiveness, and clinical benefit of these new technologies. The work is also anticipating challenges in clinical trials and developing the next generation of technology to improve on the technology as it is being commercialized today.

Feasibility of ultrasonic propulsion and burst wave lithotripsy (BWL) to noninvasively reposition distal ureteral stones to facilitate passage and relieve pain was tested. Patients presenting to the clinic or emergency department were recruited. Thirteen subjects underwent ultrasonic propulsion (lower amplitude, longer duration pulses) alone, and 10 subjects also received intermittent BWL (higher amplitude, shorter duration pulses). All participants were awake and underwent a pain assessment pre- and post-procedure. For analysis, subjects were sub-categorized based on whether their stone was acute or chronic (present for ≤10 days or >10 days from their initial ED or symptomatic presentation, respectively). Seventeen subjects were enrolled in the acute study population and 6 subjects were enrolled in the chronic population. Overall, 94% of acute stones passed in an average of 3.4 days post-procedure relative to 54% in 7.5 days in the American Urological Association guidelines. 67% of chronic cases passed stones or fragments, and two surgeries were cancelled. Pain reduction was statistically significant ( p = 0.0215). Adverse events were limited to hematuria on initial urination post-procedure (BWL only, n = 3) and a mild sensation, akin to a pinprick, associated with fewer than 10 of 620 propulsion bursts ( n = 3). [Work supported by NIH-P01-DK04331.]

OBJECTIVE To determine if use of the hematuria risk index can reduce testing and cost, while maintaining equivalent lesion detection in patients with asymptomatic microscopic hematuria. MATERIALS AND METHODS Retrospective cohort study of 1049 patients at single institution. Hematuria risk index score was calculated based on clinical factors including age, sex, smoking history, and degree of hematuria for each patient along with evaluation studies performed and total number of tumors discovered. Cost benefit analysis was performed based on published Medicare averages. RESULTS Tumor detection rate in overall, low-risk, and moderate-risk groups were 1.2%, 0%, and 2.96% at a total cost of $408,376. When low-risk group is not screened cost decreases to $166,252 with no lesions missed. The cost to discover one lesion/cancer in the overall group was $34,031.3, the cost to find one high-grade clinically significant lesion/cancer was $136,125.3 for the overall group. When the low-risk group was removed, the cost to find a high-grade clinically significant lesion/cancer decreased to $55,417.3 without missing any significant lesions. Ultrasound may be utilized instead of computed tomography with minimal loss of lesion detection in select moderate risk patients. CONCLUSION None of the low-risk hematuria risk patients were diagnosed with any lesions, as such these patients may not need an evaluation. Furthermore, by utilizing a risk-stratified approach to the assessment of asymptomatic microscopic hematuria health care costs can be significantly decreased with limited negative consequences in terms of lesion detection.

INTRODUCTION AND OBJECTIVES:The American Urologic Association Guidelines recommends obtaining a 24-hour urine (24HU) in recurrent stone formers, patients high-risk for stone recurrence, and interested first-time stone formers. However, the advantage of selective therapy based on 24HU results over empiric treatment is unclear. We aimed to determine if obtaining a 24HU in high risk stone formers is associated with decreased recurrent stone episodes in a contemporary cohort exemplifying real-world clinical practice.METHODS:We used the MarketScan database to identify insured, employed subjects, 18 to 64 years old with a primary diagnosis of kidney and/or ureteral stones based on ICD-9 and ICD-10 diagnosis codes from 2008 to 2014. Subjects at high risk for infectious stones or with cystinuria were excluded. High risk stone formers (based on AUA guidelines), those undergoing stone surgery, and those with previous stone diagnoses one year prior to the date of inclusion were characterized with CPT and ICD codes, ...

INTRODUCTION AND OBJECTIVES: In an effort to improve patient autonomy, several organizations publish online data on surgeon performance. One such organization is Pro-Publica, an independent nonprofit newsroom that publishes an online 0surgeon scorecard.0 This scorecard reports calculated death and complication rates for surgeons performing elective procedures including radical prostatectomy in Medicare patients. We wanted to understand how the general public would interpret this data and how it would impact patients’ selection of surgeon. METHODS: 265 adults at the Minnesota State Fair were asked to interpret a representative image from the Pro-Publica surgeon scorecard. Participants were told that a loved one had already scheduled cancer surgery with a surgeon they trusted. They were then shown a graphic with a dot representing the point estimate complication rate and a bar representing the 95% confidence interval (CI) of their surgeon. They were also shown a graphic with 13 other surgeons’ point estimate complication rates, all of which fell within the CI of the index surgeon’s complication rate. Another surgeon with a 0.5% lower point estimate but statistically equivalent complication rate to the first surgeon was indicated on the graphic. Participants were then asked if they would recommend switching surgeons after seeing this graphic. RESULTS: The surveyed population was educated with 89% having attended or graduated from college (n1⁄4235). Median age of participants was 50 years (range 20-74) with 68% females (n1⁄4179). Participants were from 136 different zip codes predominantly in the upper Midwest. When presented with the graphic representing two surgeons with different point estimate complication rates falling within the same confidence interval, 124 or 46.8% (95% CI 41-53) of respondents would recommend switching surgeons based on this single graphic. CONCLUSIONS: Nearly half of adults surveyed would recommend switching cancer surgeons for genitourinary malignancies based on a graphical representation of surgeons’ complication rates even though there was no statistically significant difference between the two surgeons. This suggests that simplistic displays of complicated statistical data may lead to changes in medical decision-making based on random error of measurement instead of true differences in surgeon quality.