Intravascular Lithotripsy-Assisted Transfemoral TAVI: The Copenhagen Experience and Literature Review

Transcatheter aortic valve implantation (TAVI) is currently an established therapy for elderly patients with symptomatic severe aortic valve stenosis across all surgical risk categories. Access is an important aspect when planning for and performing TAVI. The superiority of a transfemoral (TF) approach compared to a transthoracic (transapical, direct aortic) approach has been demonstrated in several studies. Recently, the introduction of intravascular lithotripsy (IVL) has made it possible to treat patients with calcified iliofemoral disease by TF approach. This article aimed to provide a comprehensive overview on the following aspects: (1) preprocedural planning for IVL-assisted TF-TAVI; (2) procedural aspects in IVL-assisted TF-TAVI; (3) outcomes of IVL-assisted TF-TAVI in an experienced TAVI center; and (4) literature review and discussion of this new emerging approach.

Neglected double-J stent with giant bladder stone: a case report

Double-J (DJ) stents have been widely utilized in urological practice. They are commonly used to relieve ureteral obstruction. Serious complications may occur when stents are left in place for long periods of time. In the present paper, we report a patient with a neglected DJ stent that had been inserted for five years after uterus-tumor surgery and led to a bladder stone. We report a case of a female who presented a bladder stone with a right DJ stent in the pelvic cavity. The stone was evident in radiological examination in an incidental finding. The treatment was transurethral cystolithotripsy. This case reminds us of the necessity of providing enough information and appropriate knowledge pertaining to the insertion of a ureteral stent. Transurethral cystolithotripsy is one of the treatment methods and can be suggested as a definitive method in consideration that it is a clinically effective and safe intervention.

The role of extracorporeal shock wave lithotripsy in the treatment of chronic pancreatitis

Pain is the most frequent symptom in chronic pancreatitis (CP) and has an important impact on quality of life. One of its major pathophysiological mechanisms is ductal hypertension, caused by main pancreatic duct stones and/or strictures. In this article, we focus on extracorporeal shock wave lithotripsy (ESWL) as a treatment for main pancreatic duct stones, which have been reported in >50% of CP patients. ESWL uses acoustic pulses to generate compressive stress on the stones, resulting in their gradual fragmentation. In patients with radiopaque obstructive main pancreatic duct (MPD) stones larger than 5 mm, located in the pancreas head or body, ESWL improves ductal clearance, thereby relieving pain and improving quality of life. In case of insufficient ductal clearance or the presence of an MPD stricture, ESWL can be followed by endoscopic retrograde cholangiopancreatography (ERCP) to increase success rate. Alternatively, direct pancreaticoscopy with intracorporeal lithotripsy or surgery can be performed.

Per-oral pancreatoscopy-guided lithotripsy for the endoscopic management of pancreatolithiasis: A systematic review and meta-analysis

OBJECTIVE

Pancreatic stones result from chronic pancreatitis and can occur in the main pancreatic duct, pancreatic branches or parenchyma. Although extracorporeal shock wave lithotripsy (ESWL) is considered the first-line treatment, per-oral pancreatoscopy (POP) has emerged as a useful method for treating pancreatic stones. The aim of this systematic review and meta-analysis was to determine the efficacy and safety of POP-guided lithotripsy, electrohydraulic lithotripsy (EHL) and laser lithotripsy (LL), in patients with pancreatolithiasis.

METHODS

Literature review was conducted in PubMed, OVID, MEDLINE and Cochrane Library databases for studies published up to August 2020.

RESULTS

Altogether 15 studies were analyzed, of which 11 were retrospective and four were prospective. The studies comprised 370 patients, of whom 66.4% were male. The patients underwent 218 EHL and 155 LL. The pooled technical and clinical success rate of the overall POP was 88.1% and 87.1%. For EHL-POP, the pooled technical success rate was 90.9% (95% CI 87.2%-95.2%) and the pooled clinical success rate was 89.8% (95% CI 87.2%-95.2%). While for LL-POP, the pooled technical and clinical success rate was 88.4% (95% CI 85.9%-95.1%) and 85.8% (95% CI 80.6%-91.6%). In total 43 adverse events occurred (12.1%; 95% CI 8.7%-15.5%).

CONCLUSION

POP-guided lithotripsy has a high rate of technical and clinical success for managing pancreatolithiasis with a low complication rate. Both EHL-POP and LL-POP achieve similar efficacy in the endoscopic therapy of pancreatolithiasis. Further large randomized controlled trials are needed to compare EHL-POP and LL-POP with ESWL and evaluate whether POP may replace ESWL as the first-line management of pancreatolithiasis.

Comparing the effect of xenon and sevoflurane anesthesia on postoperative neural injury biomarkers: a randomized controlled trial

General anesthesia and surgery are associated with an increase in neural injury biomarkers. Elevations of these neural injury biomarkers in the perioperative period are associated with postoperative delirium. Xenon has been shown to be protective against a range of neurological insults in animal models. It remains to be seen if xenon anesthesia is neuroprotective in the perioperative setting in humans. Twenty-four participants scheduled for lithotripsy were randomized to receive either xenon or sevoflurane general anesthesia. There was no statistically significant difference in the concentrations of postoperative neural injury biomarkers between the xenon and sevoflurane group. Following the procedure there was a significant increase in the concentration from baseline of all three biomarkers at 1 hour post-induction with a return to baseline at 5 hours. General anesthesia for lithotripsy was associated with a significant increase at 1 hour post-induction in the neural injury biomarkers total tau, neurofilament light and tau phosphorylated at threonine 181, a marker of tau phosphorylation. The protocol was approved by the St. Vincent’s Hospital Melbourne Ethics Committee (approval No. HREC/18/SVHM/221) on July 20, 2018 and was registered with the Australia New Zealand Clinical Trials Registry (registration No. ACTRN12618000916246) on May 31, 2018.

Long-term outcome of endotherapy for pancreatic stones by using a dedicated pancreatic basket catheter

BACKGROUND AND AIM

Although endotherapy for pancreatic stones is less invasive compared with surgical interventions, its recurrence rate is high and residual pancreatic stones can be a cause of recurrence. We previously reported usefulness of a novel basket catheter with nitinol fine reticular structure for pancreatic stone retraction. In this retrospective study, we aimed to evaluate the long-term outcomes of endotherapy for pancreatic stones with and without the use of this dedicated basket catheter.

METHODS

We retrospectively compared patients with symptomatic pancreatic stones who underwent the initial endotherapy between 2008 and 2019. The primary outcome was the symptomatic recurrence after complete stone clearance. Secondary outcomes were the rate of complete stone clearance, complications, risk factors for recurrences, and the treatment cost.

RESULTS

A total of 101 patients who underwent endotherapy for pancreatic stones were analyzed: 41 patients by using the dedicated basket catheter and 60 patients by only the conventional devices. The complete stone clearance was achieved in 87.8% in the dedicated basket group and 88.3% in the conventional device group. Symptomatic recurrence was observed in 16.7% of the dedicated basket group and 47.2% of the conventional device group (P < 0.01). In the multivariate analysis, the use of the dedicated basket catheter was significantly associated with the reduced risk of symptomatic recurrence (hazard ratio, 0.40; 95% confidence interval, 0.15-0.92, P = 0.031). The complication rate and the cost were comparable between the two groups.

CONCLUSION

The use of this dedicated pancreatic basket catheter significantly reduced symptomatic recurrence after complete pancreatic stone removal.

Intravascular imaging-guided intracoronary lithotripsy: First real-world experience

BACKGROUND AND AIMS

Coronary calcification remains a significant challenge for the contemporary interventional cardiologist. We aim to describe the use of intravascular lithotripsy (IVL) in a range of real-world settings.

METHODS

A retrospective two-center analysis of patients treated with IVL between June 2018 and November 2019. Technical and procedural success, as well as procedural complications and 30-day outcomes (death, myocardial infarction, or repeat target vessel revascularization), was recorded.

RESULTS

Sixty-five patients underwent IVL: 80% were male and the mean age was 70.1 ± 12.0 years. 54% of patients presented with acute coronary syndrome (ACS) and 68% of patients had intracoronary imaging. Twelve patients required IVL within pre-existing stents, and 12 underwent IVL in the left main stem. All balloons were successfully delivered with 98.5% procedural success. There was a significant gain in MLA post PCI of 261.9 ± 100% following IVL. There were two procedural complications. At 30-day follow-up, there was one death, and one patient required a repeat procedure due to stent underexpansion.

CONCLUSIONS

In this largest real-world series of imaging-guided IVL for calcified lesions to date, we demonstrate that IVL is deliverable, safe, and effective at calcium modification especially when intracoronary imaging is used.

A Novel Visual Grading for Ureteral Encrusted Stent Classification to Help Decide the Endourologic Treatment

Objective: The aim of the study is to propose a visual classification for encrusted stents (ESs) to help choose the appropriate endourologic treatment. Materials and Methods: A multicenter, retrospective, and descriptive study was performed. A total of 140 patients with encrusted Double-J stents were enrolled from 5 different institutions. The novel visual grading for ureteral encrusted stent (V-GUES) classification system ranges from A to D, increasing with severity of encrustation. Results: ESs could be removed with a single intervention in 112 patients (86.8%). Type A and B ESs could be removed in all patients (100% success). Type D stents had minor retrieval and stone-free rates (p = 0.006 and p < 0.0001, respectively). Flexible ureteroscopy had a low success rate (77.7%) for type C stents (odds ratio [OR]: 0.21). Combined access had a 100% success rate for retrieval of type C ESs and a 92.9% success rate for type D ESs (OR: 9.18). Type D stents were associated with patients requiring more than one session to retrieve the stent (OR: 0.11) and stones (OR: 0.21). Conclusions: The V-GUES system is associated with treatment success rates of ES retrieval and stone-free status. It is also associated with the complication rate and the number of sessions needed for patients to be stent and stone free. The V-GUES classification could help counsel patients about the best treatment options and their outcomes. Further prospective studies will be needed to provide external validation.

Clinical Observation of UreTron Single-Probe Ultrasonic Intracorporeal Lithotripter for Ureteral Calculi

Objective

The present study aimed to observe and discuss the effectiveness and safety of the UreTron single-probe ultrasonic intracorporeal lithotripter in ureteroscopic lithotripsy.

Methods

The clinical data of patients with unilateral solitary ureteral calculi treated with ureteroscopic lithotripsy who were hospitalized at the Department of Urology (West District) of Beijing Chaoyang Hospital between March 2016 and August 2020 were selected for retrospective analysis. The patients were divided into the UreTron group (group U) and holmium laser group (group H) according to the lithotripsy method adopted. The operation duration, length of hospital stay, stone clearance rate, proportion of patients requiring flexible ureteroscopy-assisted lithotripsy, and complications were compared between the groups.

Results

There was no statistical difference between the groups in terms of the general characteristics, operation duration, or length of hospital stay (P > 0.05). Regarding the stone clearance rate (group U=93.5%; group H=75%), proportion of patients requiring flexible ureteroscopy-assisted lithotripsy (group U=6.5%; group H=27.8%), and incidence of surgical complications (group U=1 case; group H=9 cases), group U was superior to group H, and the differences between the groups were statistically significant (P < 0.05). However, the differences in other complications (cardiocerebral complications and lower extremity thrombosis) were not statistically significant between the groups (P > 0.05).

Conclusion

The UreTron system is a new lithotripsy apparatus that is safe and effective for ureteroscopic lithotripsy and has certain advantages in terms of the stone clearance rate, proportion of patients requiring flexible ureteroscopy-assisted lithotripsy, and surgical complications, making it worthy of clinical application.

Overcoming very late severe calcific stenosis due to two layers of under-expanded stents with intravascular lithotripsy treatment: A case report

Intravascular lithotripsy (IVL) shockwave treatment is effective in treatment of severe calcific coronary stenosis within two layers of old under-expanded stents. Intravascular imaging is essential to analyze the mechanism of in-stent failure and optimize treatment.

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

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

Is extracorporeal shockwave lithotripsy (SWL) still suitable for >1.5 cm intrarenal stones? Data analysis of 1902 SWLs

PURPOSE

According to the American Urological Association and European Association of Urology guidelines, shockwave lithotripsy (SWL) is the least-invasive treatment option for kidney stones smaller than 2 cm. However, it is well known that SWL stone-free rates (SFR) decline as stone size increases. We sought to evaluate whether the size limit of 1.5 cm could be a better predictor of success after a single SWL session than current recommendations.

METHODS

Data from an SWL-dedicated center were prospectively scrutinized according to stone locations and sizes. Information on patients' demography, lithotripsy parameters, and outcomes was evaluated by multivariate analysis among 1902 SWLs.

RESULTS

The overall SFR was 70.8% (1347/1902). SFRs according to stone size were <1 cm: 73.8% (825/1118), 1-1.5 cm: 70.4% (401/569) and >1.5 cm: 56.2% (121/215); and according to calculi location were lower pole (LP) 64.4% (398/618), mid pole 73.8% (339/459), upper pole 73.8% (273/370) and renal pelvis 74.1% (337/455). Multivariate analysis revealed better SFR independent better SFR in <1.5 cm (p < 0.01), and non-LP stones (p < 0.01).

CONCLUSION

SWL is an effective treatment modality for kidney stones. The single session reached up to 74.8% SFRs (range 70.8%-74.8%) when indicated for intrarenal non LP stones smaller than 1.5 cm. Patients with stones >1.5 cm or >1 cm located in the LP should be counseled on the lower SFRs after a single SWL session.

Local anesthetics versus systemic analgesics for reducing pain during Extracorporeal Shock Wave Lithotripsy (ESWL): A systematic review and meta-analysis

Extracorporeal Shock Wave Lithotripsy (ESWL) is one of the treatment options for patients with renal and ureteral calculi. Even though the procedure is less invasive compared to others, pain caused by the procedure is a major concern. Several studies recommended the use of either local or systemic analgesia with varying results. We aimed to compare the use of local anesthetics and systemic analgesics from randomized controlled trials evaluating pain management during ESWL. A systematic search adhering to the Preferred Reporting Items for Systematic Review and Meta-Analysis protocol was performed in theMedline, ScienceDirect, and Cochrane library databases. The bias was evaluated using the Cochrane risk of bias tool. Mean difference (MD) was used to analyze continuous outcomes. A total of seven studies were obtained. The topical anesthesia used was eutectic mixture of local anesthetic cream and xylocaine gel. In contrast, the local injection anesthesia used was subcutaneous prilocaine and intracutaneous sterile water injection. The systemic analgesics used were intramuscular and oral forms of sodium diclofenac. There is no significant difference between the visual analogue scale results between the local and systemic groups (P> .05). The differences in ESWL frequency were also insignificant (P > .05). Additional analgesics supplementation (MD 8.44, 95% CI 2.28-14.61, P¼ .007) and the duration of the procedure (MD 1.39, 95% CI 0.21-2.56, P¼ .02) were significantly lower in the local group. Local anesthesia in ESWL shows a similar degree of pain and frequency but has a shorter duration and fewer analgesics supplementation than systemic analgesics.

Predictors of success following extracorporeal shock-wave lithotripsy in a contemporary cohort

OBJECTIVES

The objectives of this study are to determine the predictors of success following extracorporeal shock-wave lithotripsy (ESWL) in a contemporary cohort at a high-volume stone center.

METHODS

We conducted a retrospective review all patients who underwent an elective ESWL within our institution over a 24-month period (January 2014 to December 2015). Data on patient demographics, stone variables, and inpatient treatment outcomes were evaluated.The presence of residual stone fragments larger than 4 mm on follow-up imaging was considered to be treatment failure. Using this threshold, clinically relevant variables between the treatment success and failure groups were identified. Multivariable logistic regression analyses (MVA) of clinically relevant variables were used to determine the independent factors predicting ESWL success.

RESULTS

Of 446 study eligible patients, 421 patients had complete follow-up data and were included in the analysis. Treatment was successful in 72.2% of patients in this study. Stone size, number of shocks delivered, and maximum treatment intensity were statistically different in the two groups. In a MVA where stone size, location, density, presence of ureteric stent, skin-stone distance (SSD), number of shocks, and maximum shock intensity were included, only stone size of <10 mm (odds ratio [OR] 3.4 [95% confidence interval [CI]: 1.98-5.84]) and SSD <15 cm (OR: 0.133, [95% CI: 0.027-0.65]) were the independent predictor of ESWL success.

CONCLUSION

We have demonstrated "real world" outcomes with high-volume use of ESWL. In our experience that with diligent patient selection, ESWL remains an effective tool for the management of upper tract calculi.

Proteomic Signature of Urosepsis: From Discovery in a Rabbit Model to Validation in Humans

Urosepsis after upper urinary tract endoscopic lithotripsy (UUTEL) may cause uroseptic shock with high mortality, which can be prevented if early diagnosis and timely intervention are implemented with help of a diagnostic protein panel. The plasma of five rabbits of uroseptic shock and five controls was subjected to exploratory proteomics to search biomarker candidates from proteomic profiles related to uroseptic shock. Then, plasma from 21 nonsepsis and 20 urosepsis patients according to European diagnostic criteria of sepsis was enrolled in the validation study via targeted proteomics. Changes in a massive number of plasma proteins, mainly enriched in immune regulation, coagulation, structural repair, and transport activity, were observed in the rabbit model of septic shock. Fifteen proteins were identified as differential expression proteins between sepsis and nonsepsis patients. A diagnostic model composed of three proteins lipopolysaccharide-binding protein (LBP), clusterin (CLU), and vascular cell adhesion protein 1 (VCAM1) was developed for the early detection (2 hours postoperatively) of urosepsis after UUTEL, with a high area under the receiver operating characteristic (ROC) curve of 0.921. In conclusion, changes in the proteomic profile may reflect the underlying biological mechanisms during the development of urosepsis and produce diagnostic biomarkers for the early detection of urosepsis after UUTEL.

Comparison of Holmium:YAG and Thulium Fiber Lasers on the Risk of Laser Fiber Fracture

Objectives: To compare the risk of laser fiber fracture between Ho:YAG laser and Thulium Fiber Laser (TFL) with different laser fiber diameters, laser settings, and fiber bending radii. METHODS: Lengths of 200, 272, and 365 μm single use fibers were used with a 30 W Ho:YAG laser and a 50 W Super Pulsed TFL. Laser fibers of 150 µm length were also tested with the TFL only. Five different increasingly smaller bend radii were tested: 1, 0.9, 0.75, 0.6, and 0.45 cm. A total of 13 different laser settings were tested for the Ho:YAG laser: six fragmentation settings with a short pulse duration, and seven dusting settings with a long pulse duration. A total of 33 different laser settings were tested for the TFL. Three laser settings were common two both lasers: 0.5 J × 12 Hz, 0.8 J × 8 Hz, 2 J × 3 Hz. The laser was activated for 5 min or until fiber fracture. Each measurement was performed ten times. Results: While fiber failures occurred with all fiber diameters with Ho:YAG laser, none were reported with TFL. Identified risk factors of fiber fracture with the Ho:YAG laser were short pulse and high energy for the 365 µm fibers (p = 0.041), but not for the 200 and 272 µm fibers (p = 1 and p = 0.43, respectively). High frequency was not a risk factor of fiber fracture. Fiber diameter also seemed to be a risk factor of fracture. The 200 µm fibers broke more frequently than the 272 and 365 µm ones (p = 0.039). There was a trend for a higher number of fractures with the 365 µm fibers compared to the 272 µm ones, these occurring at a larger bend radius, but this difference was not significant. Conclusion: TFL appears to be a safer laser regarding the risk of fiber fracture than Ho:YAG when used with fibers in a deflected position.

Real-World Experience of Coronary Intravascular Lithotripsy in an Asian Population: A Retrospective, Observational, Single-Center, All-Comers Registry

OBJECTIVES

To assess the clinical and angiographic outcomes of coronary intravascular lithotripsy (IVL) use in an all-comers population with moderate-to-severely calcified coronary lesions.

BACKGROUND

IVL has been shown to modify coronary calcific plaques with minimal vascular complications.

METHODS

This was a retrospective, observational study of patients treated with IVL. The primary endpoint was in-hospital major adverse cardiovascular event (MACE), which included cardiac death, myocardial infarction (MI), and target-vessel revascularization (TVR). Secondary endpoints were clinical success (stent expansion with <30% in-stent residual stenosis and no in-hospital MACE) and angiographic success.

RESULTS

Between August 2019 and December 2019, a total of 50 calcified lesions were treated in 45 patients using the Shockwave C2 IVL catheter (Shockwave Medical). They were further studied in 3 treatment subgroups: (1) primary IVL group with de novo lesions (n = 23 lesions); (2) secondary IVL group in which non-compliant balloon dilation failed (n = 15 lesions); and (3) tertiary IVL group with IVL to underexpanded stents (n = 12 lesions). The mean diameter stenosis of calcified lesions was 63.2 ± 10.2% at baseline, and decreased to 33.5 ± 10.9% immediately post IVL (P<.001) and 15 ± 7.1% post stenting (P<.001). Mean minimal lumen diameter was 1.1 ± 0.3 mm at baseline, and increased to 1.90 ± 0.5 mm post IVL (P<.001) and 2.80 ± 0.50 mm post stenting (P<.001). In-hospital and 30-day MACE occurred in 3 and 4 patients, respectively. Overall, clinical success and angiographic success were achieved in 90% and 94% of cases, respectively.

CONCLUSIONS

IVL appears to be a safe, effective, and feasible strategy for calcium modification in an all-comers cohort with high success rate, minimal procedural complications, and low MACE rates.

High- and Low-Power Laser Lithotripsy Achieves Similar Results: A Systematic Review and Meta-Analysis of Available Clinical Series

Purpose: There is no clear evidence that high-power (HP) laser generators perform better than low-power (LP) ones in terms of lithotripsy outcomes. We aimed to perform a systematic review of literature to compare the efficacy outcomes of both HP and LP during ureteroscopic lithotripsy. Materials and Methods: A computerized bibliographic search of the Medline, Embase, and Cochrane databases was performed for all studies reporting perioperative outcomes of HP and LP lithotripsy. Using the methodology recommended by the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, we identified 22 nonrandomized noncomparative retrospective studies published between 2015 and 2019 that were eligible for inclusion in this systematic review. Because of the lack of comparative studies, we decided to perform two separate meta-analytic syntheses for LP and HP studies, then we compared them using a Wald-type test. Results: Overall, the selected studies included 6403 patients. Study design, exposure assessment, selection criteria, and outcome of interest were heterogeneous. LP studies were more common (n = 17, 77%), whereas HP studies were more common in the latest inclusion period. Faster lithotripsy (32.9 minutes vs 63.9 minutes, p < 0.01) was observed in HP studies. However, stone volume resulted twofold higher (2604 mm³ vs 1217 mm³, p = 0.048) in LP studies. Pooled stone-free rate was similar in both LP and HP studies, 81% and 82%, respectively, p > 0.05. No difference in complication rate was observed between the two groups, p = 0.12. Conclusions: HP laser lithotripsy appears to require shorter operative time, with similar stone-free and complication rates as compared with LP traditional lithotripsy. However, when taking into account stone burden, this advantage seems to be lost, or at least not to be comparable with what observed in laboratory studies. Because of the lack of high-level comparative evidence, further clinical studies are needed to elucidate the benefits of using HP laser generators during ureteroscopic stone treatment.

Ablation Efficiency of a Novel Thulium Fiber Laser: An In Vitro Study on Laser Setting and Fiber Usage

Introduction: To investigate the ablation efficiency of super-pulse thulium fiber laser (SPTFL) with different laser settings and fiber usage. Materials and Methods: SPTFL machine was attached with different fibers. Artificial stones were fixed in water, whereas laser fiber was driven on a platform for ablation. Pulse energy, frequency, fiber-moving speed, fiber-to-stone distance, and fiber size were adjusted in each trial. The cross-sectional area of craters on the lateral stone surface was measured for comparison of ablation rate, combined with fiber-moving speed. Results: There was a trend that the ablation rate increased as pulse energy or frequency increased. When pulse energy was set as 0.2 J and frequency was increased from 50 to 150 Hz, the cross-sectional area of the crater was enlarged from 0.21 to 0.37 mm² (p < 0.05); when the frequency was set as 100 Hz and pulse energy was increased from 0.1 to 0.3 J, the crater was enlarged from 0.10 to 0.45 mm² (p < 0.05). Furthermore, energy demonstrated greater impact on ablation rate and the crater was enlarged from 0.20 mm² in the 0.1 J × 300 Hz group to 0.44 mm² in the 0.3 J × 100 Hz group (p < 0.05). Then fiber was set at different moving speeds with the same laser setting; the ablation rate of 3 mm/second group was 3.64 times higher than 0.5 mm/second group (p < 0.05). Ablation diminished as fiber-to-stone distance grew. A 200 μm fiber produced thinner and deeper fissure than 272 and 550 μm fibers, and the ablation rate was the highest for the 200 μm fiber. Conclusion: Pulse energy is a more important factor in influencing ablation efficiency compared with frequency. Closer fiber-to-stone distance, faster fiber movement, and smaller fiber size increase ablation efficiency.

Intracoronary Lithotripsy: A New Solution for Undilatable In-Stent Chronic Total Occlusions

Percutaneous coronary intervention was performed in a flush in-stent right coronary artery chronic total occlusion. Successful retrograde recanalization was performed but the lesion was balloon undilatable as confirmed by intravascular ultrasound. High-pressure post-dilation with noncompliant and plaque modification balloons failed, but intravascular lithotripsy successfully expanded the lesion. (Level of Difficulty: Advanced.)

Gene transcripts expressed in equine white blood cells are potential biomarkers of extracorporeal shock wave therapy

Extracorporeal shockwave therapy (ESWT) is a treatment applied to musculoskeletal injuries in equine athletes to alleviate pain and accelerate healing. ESWT also causes acute tissue damage. Therefore, its ability to act as an analgesic and cause tissue damage potentially increases the risk of a catastrophic event if used shortly before a strenuous competition such as horseracing. While ESWT is prohibited by many racing jurisdictions within 10 days prior to competition, a test to detect whether a horse has received ESWT is needed. ESWT changes the protein levels of inflammatory mediators in blood, and white blood cells (WBC) typically produce these proteins. Changes in gene expression precede changes in protein production; thus, it was hypothesized that WBC gene transcripts might serve as biomarkers of ESWT. To test this hypothesis, six thoroughbred horses received a single administration of ESWT to the distal limb, and WBC RNA was extracted from blood samples collected before (0 h) and after ESWT (2, 4, 6, 24, 48, and 72 h). Targeted and untargeted analyses evaluated the transcriptome using quantitative PCR (qPCR) and microarray. The expression of IL-1α, IL-1β, TNF-α, IL-1Ra1, IL-1Ra2 and TGF-β1, and BMPR1A in circulating WBCs was significantly up-regulated, while IFN-γ, ZNF483, TMEM80, CAH6, ENPP, and S8723 were significantly down-regulated at various time points following ESWT. These data support the hypothesis that changes in WBC gene transcripts could serve as biomarkers for ESWT.

Automated Generation of Personalized Shock Wave Lithotripsy Protocols: Treatment Planning Using Deep Learning

Background

Though shock wave lithotripsy (SWL) has developed to be one of the most common treatment approaches for nephrolithiasis in recent decades, its treatment planning is often a trial-and-error process based on physicians’ subjective judgement. Physicians’ inexperience with this modality can lead to low-quality treatment and unnecessary risks to patients.

Objective

To improve the quality and consistency of shock wave lithotripsy treatment, we aimed to develop a deep learning model for generating the next treatment step by previous steps and preoperative patient characteristics and to produce personalized SWL treatment plans in a step-by-step protocol based on the deep learning model.

Methods

We developed a deep learning model to generate the optimal power level, shock rate, and number of shocks in the next step, given previous treatment steps encoded by long short-term memory neural networks and preoperative patient characteristics. We constructed a next-step data set (N=8583) from top practices of renal SWL treatments recorded in the International Stone Registry. Then, we trained the deep learning model and baseline models (linear regression, logistic regression, random forest, and support vector machine) with 90% of the samples and validated them with the remaining samples.

Results

The deep learning models for generating the next treatment steps outperformed the baseline models (accuracy = 98.8%, F1 = 98.0% for power levels; accuracy = 98.1%, F1 = 96.0% for shock rates; root mean squared error = 207, mean absolute error = 121 for numbers of shocks). The hypothesis testing showed no significant difference between steps generated by our model and the top practices (P=.480 for power levels; P=.782 for shock rates; P=.727 for numbers of shocks).

Conclusions

The high performance of our deep learning approach shows its treatment planning capability on par with top physicians. To the best of our knowledge, our framework is the first effort to implement automated planning of SWL treatment via deep learning. It is a promising technique in assisting treatment planning and physician training at low cost.