Shock wave technology and application: an update

Contralateral Coupling During Extracorporeal Shockwave Lithotripsy for Stones in Ectopic Kidney: Is It Feasible?

Purpose: Extracorporeal shockwave lithotripsy (SWL) results in a lower stone-free rate (SFR) for ectopic kidneys when using the standard technique, directing the shock wave from the same side of the stone; however, this may not be the optimal approach when the ectopic kidney is located more medial and anterior than the normally positioned kidney. Thus, contralateral coupling where waves come from the opposite direction may result in a better outcome. We tested the feasibility and outcome of contralateral coupling during SWL for stone in ectopic kidney. Materials and Methods: We prospectively recruited 20 patients with simple renal ectopia, who presented with renal stones that were amenable for SWL in the period between 2014 and 2018 at outpatient clinic of urology department, Minia University. Patients received SWL in Private Nile SWL Center were included to benefit from the ability of the electromagnetic SWL lithotripter. We did SWL in a supine position, and then contralateral coupling was performed from the opposite side of the affected kidney, rather than using the standard ipsilateral coupling approach. The SFR and various pre-, intra-, and postprocedural SWL variables were assessed, including stone characteristics, body habitus, shock wave numbers, and auxiliary measures. Count and percentages were calculated. Results: The mean stone radius was 14.7 mm with a mean S.T.O.N.E. (size, topography, obstructions, number of stones, and evaluation of HUs) of 9.6 points. Effective SWL was achieved in 80% of cases, 65% of them were stone free with effective single SWL session in 56% of cases. Hematuria, infection, and obstruction occurred in 50%, 20%, and 15% cases, respectively. One case required ureteral stent insertion. Conclusions: SWL applied through contralateral coupling is feasible, with comparable safety profile to the standard ipsilateral approach. Better SFR was achieved with the contralateral approach, in fewer sessions. However, the recruitment of more cases is necessary.

The impact of extracorporeal shock wave therapy for the treatment of young patients with vasculogenic mild erectile dysfunction: A prospective randomized single-blind, sham controlled study

BACKGROUND

Low-intensity extracorporeal shock wave therapy (ESWT) for the treatment of vasculogenic erectile dysfunction (ED) has emerged as a promising method directly targeting the underlying pathophysiology of the disease.

OBJECTIVES

To compare outcomes in ED patients after ESWT and placebo treatment.

MATERIALS AND METHODS

Prospective randomized placebo-controlled single-blinded trial on 66 patients with mild ED. The study comprised a 4-week washout phase, a 4-week treatment phase, and a 48-week follow-up. Inclusion criteria included age between 18 and 75 years and diagnosis of mild ED (IIEF-EF score = 17-25) being made at least six months prior to study inclusion and being confirmed by Penile Doppler ultrasonography (US) at baseline examination. Efficacy endpoints were changes from baseline in patient-reported outcomes of erectile function (International Index of Erectile Function domain scores [IIEF-EF]), as well as erection hardness and duration (Sexual Encounter Profile diary [SEP] and Global Assessment Questions [GAQ]). Safety was assessed throughout the study.

RESULTS

A total of 66 enrolled patients were allocated to ESWT (n = 44) or placebo (n = 22). Mean age of ESWT and placebo group was 42.32 ± 9.88 and 39.86 ± 11.64 (p = 0.374), respectively. Mean baseline IIEF-EF scores of ESWT group and placebo were 20.32 ± 2.32 and 19.68 ± 1.55 respectively (p = 0.34). At 3-months follow-up, mean IIEF-EF scores were significantly higher in ESWT patients than in placebo patients (23.10 ± 2.82 vs. 20.95 ± 2.19, p = 0.003), and IIEF-EF scores of ESWT patients remained high during the 6 months (22.67 ± 3.35 vs. 19.82 ± 1.56) follow-up. The percentage of patients reporting both successful penetration (SEP2) and intercourse (SEP3) in more than 50% of attempts was significantly higher in ESWT-treated patients than in placebo patients (p = 0.001). A minimal clinically important difference between the IIEF = EF baseline and 3-months follow-up was found in 74% of ESWT and 36% of placebo. No serious adverse events were reported.

DISCUSSION AND CONCLUSION

ESWT significantly improved the erectile function of relatively young patients with vasculogenic mild ED when compared to placebo and the beneficial effect of this treatment up to 6 months. These findings suggest that ESWT could be a useful treatment option in vasculogenic ED.

Safety Review and Perspectives of Transcranial Focused Ultrasound Brain Stimulation

Ultrasound is an important theragnostic modality in modern medicine. Technical advancement of both acoustic focusing and transcranial delivery have enabled administration of ultrasound waves to localized brain areas with few millimeters of spatial specificity and penetration depth sufficient to reach the thalamus. Transcranial focused ultrasound (tFUS) given at a low acoustic intensity has been shown to increase or suppress the excitability of region-specific brain areas. The neuromodulatory effects can outlast the sonication, suggesting the possibility of inducing neural plasticity needed for neurorehabilitation. Increasing numbers of studies have shown the efficacy and excellent safety profile of the technique, yet comparisons among the safety-related parameters have not been compiled. This review aims to provide safety information and perspectives of tFUS brain stimulation. First, the acoustic parameters most relevant to thermal/mechanical tissue damage are discussed along with regulated parameters for existing ultrasound therapies/diagnostic imaging. Subsequently, the parameters used in studies of large animals, non-human primates, and humans are surveyed and summarized in terms of the acoustic intensity and the mechanical index. The pulse-mode operation and the use of low ultrasound frequency for tFUS-mediated brain stimulation warrant the establishment of new safety guidelines/recommendations for the use of the technique among healthy volunteers, with additional cautionary requirements for its clinical translation.

Low-intensity extracorporeal shock wave therapy for male chronic pelvic pain syndrome: a systematic review and meta-analysis

Background

A systematic review of the evidence was conducted to evaluate the efficacy of low-intensity extracorporeal shock wave therapy (LI-ESWT) for patients with chronic pelvic pain syndrome (CPPS).

Methods

A comprehensive search was undertaken of the Cochrane Register, PubMed, and Embase databases for controlled trials that evaluated patients with CPPS who were treated with LI-ESWT and that were published before August 2019. The National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) was the most frequently used tool to evaluate the treatment efficacy of LI-ESWT. The NIH-CPSI comprises subscales for pain [using a visual analog scale (VAS)], urinary function, and quality of life (QoL).

Results

Six studies analyzing 317 patients were published from 2009 to 2019. The overall meta-analysis of the data indicated that LI-ESWT demonstrated efficacy in the treatment of CPPS at 12 weeks [risk difference (RD): 0.46; 95% confidence interval (CI), 0.28–0.63; P<0.00001]. The studies were divided into 3 groups based on time after LI-ESWT (1, 12, and 24 weeks) and were compared in total NIH-CPSI scores, QoL, VAS scores, and urinary symptoms. The total NIH-CPSI scores, QoL, VAS scores, and urinary symptom scores improved significantly at 12 weeks after LI-ESWT (P<0.05), but not at 1 week or 24 weeks (P>0.05).

Conclusions

Based on these studies, LI-ESWT may transiently improve the total NIH-CPSI scores, QoL, pain scores, and urinary symptom scores of patients with CPPS. Future research may elucidate the mechanisms underlying the effects of LI-ESWT on CPPS. Well-designed and long-term multicenter randomized controlled trials are urgently needed to estimate the real potential and ultimate use of these devices in patients with CPPS.

[Stone therapy-use and limitations of the guidelines]

Increase of medical knowledge, technical innovation together with a demographic change, and increase of stone incidence in daily practice challenges guideline preparation and clinical studies. Increasing interdisciplinary collaboration in stone treatment can also be demonstrated in the number of affiliated professional and working groups in the current guideline update. The following case illustrates treatment options in a symptomatic patient harbouring bilateral stones and metabolic risk factors. Decision guidance for treatment and recurrence prevention measures are presented on the basis of expert opinion and available published evidence.

A review of ultrasound-mediated microbubbles technology for cancer therapy: a vehicle for chemotherapeutic drug delivery

Background:

The unique behaviour of microbubbles under ultrasound acoustic pressure makes them useful agents for drug and gene delivery. Several studies have demonstrated the potential application of microbubbles as a non-invasive, safe and effective technique for targeted delivery of drugs and genes. The drugs can be incorporated into the microbubbles in several different approaches and then carried to the site of interest where it can be released by destruction of the microbubbles using ultrasound to achieve the required therapeutic effect.

Methods:

The objective of this article is to report on a review of the recent advances of ultrasound-mediated microbubbles as a vehicle for delivering drugs and genes and its potential application for the treatment of cancer.

Conclusion:

Ultrasound-mediated microbubble technology has the potential to significantly improve chemotherapy drug delivery to treatment sites with minimal side effects. Moreover, the technology can induce temporary and reversible changes in the permeability of cells and vessels, thereby allowing for drug delivery in a spatially localised region which can improve the efficiency of drugs with poor bioavailability due to their poor absorption, rapid metabolism and rapid systemic elimination.

Three-phase vaporization theory for laser-activated microcapsules

Precision control of vaporization, both in space and time, is critical for numerous applications, including medical imaging and therapy, catalysis and energy conversion, and it can be greatly improved through the use of micro- or nano-sized light absorbers. Ultimately, optimization of these applications also requires a fundamental understanding of the vaporization process. Upon laser irradiation, polymeric microcapsules containing a dye can vaporize, leading to the growth of a vapor bubble that emits a strong acoustic signature. Here, we compare laser-activated capsules containing either a volatile or a non-volatile oil core. We theoretically explore the vaporization of the capsules based on a three-phase thermodynamics model, that accounts for the partial vaporization of both the surrounding fluid and the oil core as well as for the interaction between heat transfer and microbubble growth. The model is compared to ultra-high-speed imaging experiments, where we record the cavitation events. Theory and experiments are in convincing agreement.

Comparing 60 versus 120 shocks per minute for shock-wave lithotripsy of solitary renal calculi: A controlled randomized study

Objective:

This study aimed to compare the difference in outcome of shock-wave lithotripsy (SWL) using a slow rate of 60 shocks per minute versus a rapid rate of 120 shocks per minute generated by an electromagnetic lithotripter for renal calculi.

Methods:

From May 2017 to June 2019, 156 patients ( Mage=38.7 years) with single radio-opaque renal stones smaller than 20 mm were included and randomly divided into two groups: group A, 78 patients who received 60 shocks per minute; and group B, 78 patients who received 120 shocks per minute. Patients were radiologically reviewed at 3 months for an outcome.

Results:

There was no statistically significant difference between mean stone area treated ( p=0.222) or additional analgesic use in the form of patient-controlled analgesia (PCA; alfentanil; p=0.82). A successful outcome was defined by fragments smaller than 4 mm or stone-free status. In group A, 60% of patients had a successful outcome compared with 61.4% in group B ( p=0.869) following a single treatment. Post-treatment complications were similar in both groups at 12% for group A and 10.7% for group B ( p=0.797).

Conclusions:

There was no statistically significant difference between the delivery of 60 and 120 shocks per minute during SWL for the treatment of solitary renal stones with a mean stone area of 62 mm2 regarding the outcome, complications or PCA use when using a Dornier Compact Delta II lithotripter.

Low-intensity extracorporeal shock wave therapy for III B chronic pelvic pain syndrome

Background

To analyze the efficiency of low-intensity shock wave therapy (LI-ESWT) for patients with III B chronic pelvic pain syndrome (CPPS).

Methods

The study included an uncontrolled population of 32 patients who had suffered with CPPS for ≥3 months. LI-ESWT was performed without anesthesia via a perineal approach. The operation was carried out in four weeks by administering 12,000 shock waves. Using the Visual Analog Scale (VAS) and NIH-developed Chronic Prostatitis Symptom Index (NIH-CPSI), subsequent tests were performed at 1, 2, 4, and 12 weeks after the first LI-ESWT session.

Results

All patients who received the four week course as treatment responded actively on the pain VAS and the NIH-CPSI, and both were significantly improved (P<0.05). Compared with the baseline parameters, the NIH-CPSI total score and VAS exhibited substantial improvement at 4 and 12 weeks, where a total improvement at four weeks was reached. It is easy and safe to perform LI-ESWT without anesthesia on an outpatient basis.

Conclusions

LI-ESWT should be regarded as a promising new therapy for CPPS, as it is convenient to perform without any side-effects.

Therapeutic effects of Low intensity extracorporeal low energy shock wave therapy (LiESWT) on stress urinary incontinence

This study aimed to evaluate the therapeutic effects of Low intensity extracorporeal low energy shock wave therapy (LiESWT) on stress urinary incontinence (SUI). The investigation was a single-arm, open-label, multicentre study conducted in Taiwan. 50 female patients with SUI received LiESWT-treated with 0.25 mJ/mm² intensity, 3000 pulses, and 3 pulses/second, once weekly for 4-weeks (W4) and 8-weeks (W8). The pad test, uroflowmetry, life quality questionnaires, and 3-day urinary diary measurement were performed before and after LiESWT intervention. The results revealed that 8-week of LiESWT treatment meaningfully improved urine leakage (pad test), maximum flow rate, post-voided residual urine, average urine volume, functional bladder capacity, urinary frequency, urgency symptom, and nocturia, which also persisted to show significant improvements at 1-month follow up (F1). Moreover, bothersome questionnaires scores were significantly improved at W4, W8, and F1 as compared to the baseline (W0). These results indicated that 8 weeks of LiESWT attenuated SUI symptoms on physical activity, reduced bladder leaks and overactive bladder (OAB), implying that LiESWT brought significant improvement in the quality of life. (ClinicalTrials.gov number, NCT04059133).

Role and mechanism of micro-energy treatment in regenerative medicine

With the continuous integration and intersection of life sciences, engineering and physics, the application for micro-energy in the basic and clinical research of regenerative medicine (RM) has made great progress. As a key target in the field of RM, stem cells have been widely used in the studies of regeneration. Recent studies have shown that micro-energy can regulate the biological behavior of stem cells to repair and regenerate injured organs and tissues by mechanical stimulation with appropriate intensity. Integrins-mediated related signaling pathways may play important roles in transducing mechanical force about micro-energy. However, the complete mechanism of mechanical force transduction needs further research. The purpose of this article is to review the biological effect and mechanism of micro-energy treatment on stem cells, to provide reference for further research.

Extracorporeal shock-wave lithotripsy: is it still valid in the era of robotic endourology? Can it be more efficient?

PURPOSE OF REVIEW

The aim of the article is to evaluate the actual role of extracorporeal shock-wave lithotripsy (ESWL) in the management of urolithiasis based on the new developments of flexible ureterorenoscopy (FURS) and percutaneous nephrolithotomy (PCNL).

RECENT FINDINGS

In Western Europe, there is a significant change of techniques used for treatment of renal stones with an increase of FURS and a decrease of ESWL. The reasons for this include the change of indications, technical improvement of the endourologic armamentarium, including robotic assistance. Mostly relevant is the introduction of digital reusable and single-use flexible ureterorenoscopes, whereas micro-PCNL has been abandoned. Some companies have stopped production of lithotripters and novel ideas to improve the efficacy of shock waves have not been implemented in the actual systems. Promising shock-wave technologies include the use of burst-shock-wave lithotripsy (SWL) or high-frequent ESWL. The main advantage would be the very fast pulverization of the stone as shown in in-vitro models.

SUMMARY

The role of ESWL in the management of urolithiasis is decreasing, whereas FURS is constantly progressing. Quality and safety of intracorporeal shock-wave lithotripsy using holmium:YAG-laser under endoscopic control clearly outweighs the advantages of noninvasive ESWL. To regain ground, new technologies like burst-SWL or high-frequent ESWL have to be implemented in new systems.

The effect of focus size and intensity on stone fragmentation in SWL on a piezoelectric lithotripter

Purpose

We aim to analyze the efficacy of different focus sizes and the influence of pulse pressure (intensity) during shock wave lithotripsy (SWL) in terms of stone fragmentation.

Methods

Combination of three focal sizes (F1 = 2 mm, F2 = 4 mm, F3 = 8 mm) and 11 output pressure settings (intensity 10–20) of a piezoelectric lithotripter (Wolf PiezoLith 3000) were tested on artificial stones (n = 99). The stones were placed within a 2 mm mesh cage. The needed number of shockwaves (SW) to first visible crack, 50% and 100% stone disintegration were recorded.

Results

Similar number of SW’s were observed until the first crack 10, 11 and 11 SW’s for F1, F2, and F3, respectively (p > 0,05). The median number of SW needed for 50% stone disintegration was 245 for F1 group, 242 for F2 group and 656 for F3 group. F1 vs F2 p = 0.7, F1 vs F3 and F2 vs F3 p < 0.05. Similarly, with larger focus size a higher number of shockwaves were necessary for 100% stone disintegration. 894, 877 and 1708 SW’s for F1, F2 and F3, respectively. Only for F1 vs F3 and F2 vs F3 (all p < 0.05) a statistical difference was observed. These findings were consistent in all different power settings, with an increased difference in lower power levels (≤ 14).

Conclusions

A smaller focus size, as well as a higher peak pressure results in a more effective stone fragmentation. However, these results need to be confirmed in an in vivo setting with multiple parameters interfering the efficacy, like BMI, respiration or stone migration.

Two-shift operation mode can improve the efficiency and comfort of flexible ureteroscopic holmium laser lithotripsy for the treatment of renal calculi larger than 1.5cm

Purpose:

To compare two-shift operation mode and single player mode different impact on surgical results and operator comfort in flexible ureteroscopic holmium laser lithotripsy for renal calculi larger than 1.5cm.

Materials and Methods:

From december 2017 to december 2018, 92 patients with renal calculi admitted to Qilu Hospital and were treated through flexible ureteroscopy. They were randomized in two-shift group (n=50) and single player group (n=42). The operative time, blood loss, hospitalization stay after operation, residual fragments (≥4mm) rate, fragmentation speed, postoperative complications and operator's fatigue score were compared.

Results:

There was no significant difference between two groups regarding age, gender, illness side, stone size, blood loss, operative time, postoperative hospitalization stay, complications, etc (p >0.05). The fragmentation speed was 44.5±20.0mm3/min in two-shift group compared with 34.2±17.3mm3/min in single player group (p=0.037). Residual fragments (≥4mm) rate after first surgery was 18% in two-shift group, while the residual fragments (≥4mm) rate was 40.5% after first surgery in single player group (p=0.017). The total fatigue score of two-shift group was 8.4 compared to 29.9 in single player group (p <0.001).

Conclusion:

In flexible ureteroscopic holmium laser lithotripsy for the treatment of renal calculi larger than 1.5cm, two-shift operation mode can raise the fragmentation speed and stone clearance rate, as well as significantly lower operator's fatigue level and improve operator's comfort.

Optimisation of shock wave lithotripsy: a systematic review of technical aspects to improve outcomes

Shock wave lithotripsy (SWL) remains an important treatment option for the management of upper urinary tract stones. The optimisation of certain technical principles can help to improve the results of SWL. We performed a systematic review based on preferred reporting items for systematic review and meta-analysis (PRISMA) standards for studies reporting on technical aspects of SWL. A literature search was conducted on the PubMed database between January 1984 and November 2018 using 'shockwave lithotripsy' and 'stone' as keywords. Summaries and manuscripts of relevant articles were reviewed in order to select studies with the best level of evidence in each theme covered during the review. From 4,135 titles, 165 abstracts and full-text articles were reviewed. Overall, SWL has good outcomes in the treatment of upper urinary tract stones. It remains the only truly non-invasive stone treatment. While stone-free rate (SFR) might not be equivalent to ureteroscopy or percutaneous nephrolithotomy outcomes, SWL can be optimised by changing several technical factors, including type of machine, patient position, number, rate and energy of shocks, stone targeting, and patient analgesia. For each of these included SWL themes, relevant and selected studies with the highest level of evidence were described and discussed. Paired with these improved technical factors and appropriate patient selection, SWL, with its low complication rates, remains an excellent treatment option in 2019.

Low-Intensity Shock Wave Therapy in Sexual Medicine-Clinical Recommendations from the European Society of Sexual Medicine (ESSM)

INTRODUCTION

Low-intensity shockwave therapy (LISWT) has been investigated for the treatment of uroandrological disorders including erectile dysfunction (ED), Peyronie's disease (PD) and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) with controversial findings.

AIM

To review the evidence on LISWT for ED, PD, and CP/CPPS and provide clinical recommendations on behalf of the European Society of Sexual Medicine.

METHODS

Medline and Embase databases were searched for randomized clinical trials (RCTs), meta-analyses and open-label prospective or retrospective studies investigating the effect of LISWT on ED, PD, or CP/CPPS.

OUTCOMES

The panel provided statements on clinically relevant questions concerning LISWT: (i) treatment efficacy, (ii) treatment protocol, (iii) clinical indications, and (iv) safety. The level of evidence was provided according to the Oxford 2011 criteria and graded using the Oxford Centre for Evidence-Based Medicine recommendations.

RESULTS

11 RCTs and 5 meta-analyses investigated LISWT for ED. RCTs provided controversial results on the efficacy of LISWT and were affected by high heterogeneity and the small number of patients included. Pooled-data analysis showed an overall positive effect in terms of erectile function improvement but reported small estimates and included a largely heterogeneous cohort of patients. 4 RCTs and 1 meta-analysis assessed LISWT for PD. All trials showed positive findings in terms of pain relief but no effect on penile curvature and plaque size. Inclusion criteria vary widely among studies, and further investigation is needed. 5 RCTs investigated LISWT for CP/CPPS. Data showed a possible effect on pain relief, although there is no evidence supporting that pain relief was maintained or any improvement in pain over time.

CLINICAL IMPLICATIONS

LISWT needs to be further investigated in the context of sexual medicine and is almost but not yet ready for clinical practice.

STRENGTHS AND LIMITATIONS

All studies have been evaluated by a panel of experts providing recommendations for clinical practice.

CONCLUSIONS

LISWT is a safe and well-tolerated procedure but its efficacy for the treatment of ED is doubtful and deserves more investigation. Patients reporting pain associated with PD may benefit from LISWT, although no effect is expected on disease progression. LISWT is not a primary treatment for CP/CPPS, but it may be considered as an option to relieve pain. Capogrosso P, Frey A, Jensen CFS, et al. Low-Intensity Shock Wave Therapy in Sexual Medicine-Clinical Recommendations from the European Society of Sexual Medicine (ESSM). J Sex Med 2019;16:1490-1505.

Is radial extracorporeal shock wave therapy combined with a specific rehabilitation program (rESWT + RP) more effective than sham-rESWT + RP for acute hamstring muscle complex injury type 3b in athletes? Study protocol for a prospective, randomized, double-blind, sham-controlled single centre trial

Background

Acute injuries of the hamstring muscle complex (HMC) type 3b (interfascicle/bundle-tear) are frequently observed in various sports disciplines both in elite and recreational sport. The treatment of choice of acute HMC injuries type 3b is a progressive physiotherapeutic exercise programme. Besides this, there is currently only insufficient scientific evidence to support other treatment methods, including local infiltrations and injections of platelet-rich-plasma. Very recently, it was demonstrated that extracorporeal shock wave therapy (ESWT) may accelerate regeneration after acute skeletal muscle injury. The aim of the present study is to test the hypothesis that the combination of radial ESWT (rESWT) and a specific rehabilitation program (RP) is effective and safe in treatment of acute HMC injury type 3b in athletes, and is statistically significantly more effective than the combination of sham-rESWT and RP.

Methods

We will perform a double blind, randomized, sham-controlled clinical trial at the clinic KinEf Kinesiología Deportiva, Ciudad Autónoma de Buenos Aires, Argentina. Forty patients with acute HMC injury type 3b will be randomly allocated to receive either rESWT (nine rESWT sessions; three sessions per week; 2500 radial extracorporeal shock waves (rESWs) per session; energy density depending on what the patient tolerates) or sham-rESWT. In addition, all patients will receive a specific rehabilitation program that will last for 8 weeks. The primary outcome measure will be the individual time (days) necessary to return to play. Secondary outcomes will include the presence or absence of reinjury during a time period of 6 months after inclusion into the study.

Discussion

Because of the lack of adequate treatment options for acute HMC injury type 3b in athletes and particularly the high reinjury rate, we hypothesize that the results of this trial will be of importance and have impact on clinical practice.

Trial registration

ClinicalTrials.gov ID NCT03473899. Registered March 22, 2018.

Update on Surgical Management of Pediatric Urolithiasis

Urolithiasis has always been a fascinating disease, even more so in children. There are many intriguing facets to this pathology. This article is a nonsystematic review to provide an update on the surgical management of pediatric urolithiasis. It highlights the pros and cons of various minimally invasive surgical options such as extracorporeal shockwave lithotripsy (ESWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), laparoscopy, and robotics. This article also describes the various intracorporeal disintegration technologies available to fragment the stone, including the newer advancements in laser technology. It also emphasizes the cost considerations especially with reference to the emerging economies. Thus, this manuscript guides how to select the least-invasive option for an individual patient, considering age and gender; stone size, location, and composition; and facilities and expertise available.

The Impact of Dust and Confinement on Fragmentation of Kidney Stones by Shockwave Lithotripsy in Tissue Phantoms

Objective: The goal was to test whether stone composition and kidney phantom configuration affected comminution in extracorporeal shockwave lithotripsy (SWL) laboratory tests. Confinement may enhance the accumulation of dust and associated cavitation bubbles in the fluid surrounding the stone. It is known that high shockwave delivery rates in SWL are less effective because bubbles generated by one shockwave do not have sufficient time to dissolve, thereby shielding the next shockwave. Materials and Methods: Experiments were conducted with a lithotripter coupled to a water bath. The rate of comminution was measured by weighing fragments over 2 mm at 5-minute time points. First, plaster and crystal stones were broken in four phantoms: a nylon wire mesh, an open polyvinyl chloride (PVC) cup, a closed PVC cup, and an anatomical kidney model-the phantoms have decreasing fluid volumes around the stone. Second, the fluid volume in the kidney model was flushed with water at different rates (0, 7, and 86 mL/min) to remove dust. Results: The efficiency of breakage of stones decreases for the dust emitting plaster stones (percentage of breakage in 5 minutes decreased from 92% ± 2% [n = 3] in wire mesh to 19% ± 3% [n = 3] in model calix) with increasing confinement, but not for the calcite crystal stones that produced little dust (percentage of breakage changed from 87% ± 3% [n = 3] in wire mesh to 81% ± 3% [n = 3] in kidney model). Flushing the kidney phantom at the fastest rate improved comminution of smaller plaster stones by 27%. Conclusions: Phantoms restricting dispersion of dust were found to affect stone breakage in SWL and in vitro experiments should replicate kidney environments. The dust around the stone and potential cavitation may shield the stone from shockwaves and reduce efficacy of SWL. Understanding of stone composition and degree of hydronephrosis could be used to adapt patient-specific protocols.

Extracorporeal Shock Wave Therapy in Peyronie's Disease: Clinical Efficacy and Safety from a Single-Arm Observational Study

Purpose

In this study, we aimed to determine the role of extracorporeal shockwave therapy (ESWT) in the management of Peyronie's disease (PD).

Materials and Methods

A total of 325 patients suffering from PD were enrolled in this single-arm clinical study. All patients were received ESWT using a schedule of 1 treatment/wk. Penile curvature was measured by a goniometer after intracavernosal drug-induced erection using Alprostadil. Plaque size was measured with a ruler and sexual function assessed by the international index of erectile function (IIEF)-15 score. Severity of erectile dysfunction was classified as severe (IIEF-15 ≤10), moderate (IIEF-15 between 11 and 16), or mild (IIEF-15 between 17 and 25). Results were evaluated at baseline and 3 months after the treatment.

Results

All the patients completed the study protocol. Median age was 59.0 years (55.0–64.0 years). After treatment, the median (interquartile range, IQR) plaque size reduced from 1.78 cm² (1.43–2.17 cm²) to 1.53 cm² (1.31–1.96 cm²) (p<0.001); the median (IQR) penile length in erection increased from 13.0 cm (12.0–14.0 cm) to 14 cm (13.0–15.0 cm) (p<0.001) and the median (IQR) penile curvature from 30.4° (22.2°–35.4°) to 25.0° (20.2°–30.4°) (p<0.001). We also observed a decrease in pain assessed by visual analogue scale (7 vs. 3; p<0.001), an improvement in each of the IIEF sub-domains (p<0.001) and an improvement in all three PD questionnaire domains (p<0.001).

Conclusions

Based on our findings, ESWT could be considered a safe and efficient minimally invasive option for the management of the patients suffering from PD.

Endometriosis treatment with shock waves: A novel approach

Endometriosis affects 10-15% of women. When medication is unsatisfactory, not well tolerated or unwanted, surgery remains the sole option. There is a need for a less invasive treatment. We suggest the application of shock wave therapy (SWT) to endometriotic nodules (including deep infiltrating endometriosis), endometriomas and adenomyosis. We hypothesize pain relief via an antiinflammatory effect, an antioxidant effect and neural pathways modulation, as well as a direct effect on the lesions by the energy thus delivered. Questions to be answered before a clinical application is tested include route of administration (external versus internal transducers), dose regimen, optimal duration of treatment and type of shock waves used (focalised versus radial).

Simulation of Laser Lithotripsy-Induced Heating in the Urinary Tract

PURPOSE

Holmium laser lithotripsy is a common modality used to fragment urinary stones during ureteroscopy. Laser energy deposited during activation produces heat and potentially causes thermal bioeffects. We aimed to characterize laser-induced heating through a computational simulation.

MATERIALS AND METHODS

A finite-element model was developed and used to estimate temperature in the urinary tract. Axisymmetric models of laser lithotripsy in a renal calyx, the renal pelvis, and proximal ureter were created. Heat generation by laser and heat transfer were simulated under different laser powers between 5 and 40 W. Irrigation fluid flow was introduced at rates between 0 and 40 mL/min. The model was validated by comparison with previous in vitro temperature data in a test tube, then used to calculate heating and thermal dose in the three tissue models.

RESULTS

Simulated temperature rises agreed well with most in vitro experimental measurements. In tissue models, temperature rises depended strongly on laser power and irrigation rate, and to a lesser extent on location. Injurious temperatures were reached for 5-40 W laser power without irrigation, >10 W with 5 mL/min irrigation, 40 W with 15 mL/min irrigation, and were not found at 40 mL/min irrigation. Tissue injury volumes up to 2.3 cm³ were calculated from thermal dose.

CONCLUSIONS

The results suggest a numerical model can accurately simulate the thermal profile of laser lithotripsy. Laser heating is strongly dependent on parameters and may cause a substantial temperature rise in the fluid in the urinary tract and surrounding tissue under clinically relevant conditions.

Cellular signaling pathways modulated by low-intensity extracorporeal shock wave therapy

Low-intensity extracorporeal shock wave therapy (Li-ESWT) is a form of energy transfer that is of lower intensity (<0.2mJ/mm²) relative to traditional Extracorporeal Shock Wave Lithotripsy (ESWL) used for management of urinary stones. At this intensity and at appropriate dosing energy transfer is thought to induce beneficial effects in human tissues. The proposed therapeutic mechanisms of action for Li-ESWT include neovascularization, tissue regeneration, and reduction of inflammation. These effects are thought to be mediated by enhanced expression of vascular endothelial growth factor, endothelial nitric oxide synthase, and proliferating cell nuclear antigen. Upregulation of chemoattractant factors and recruitment/activation of stem/progenitor cells may also play a role. Li-ESWT has been studied for management of musculoskeletal disease, ischemic cardiovascular disorders, Peyronie's Disease, and more recently erectile dysfunction (ED). The underlying mechanism of Li-ESWT for treatment of ED is incompletely understood. We summarize the current evidence basis by which Li-ESWT is thought to enhance penile hemodynamics with an intention of outlining the fundamental mechanisms by which this therapy may help manage ED.

Fragmentation of brittle material by shock wave lithotripsy. Momentum transfer and inertia: a novel view on fragmentation mechanisms

Shock wave lithotripsy is the only non-invasive stone therapy and in clinical use since 1980. In spite of decades with millions of patients treated, the mechanism of fragmentation is still under debate. Detailed knowledge of the fragmentation process is required for improvements regarding safety and efficiency. The purpose of this paper is to gain a deeper insight into the mechanism of fragmentation by drawing attention to basic physical laws of inertia and momentum transfer. Many fragmentation experiments are based on the overall efficiency of multiple shock waves in crushing kidney stones or artificial model stones utilizing small baskets or latex pouches. Due to the high dynamic nature of the fragmentation process, in vitro and in vivo, a detailed action of a single shock wave on a particular stone target is difficult to investigate. We utilized a bifilar stone suspension, which allowed us to observe horizontal movements of model stones, their return to the initial position and orientation for repeated exposure of separate identical shocks. The method does not describe the entire fragmentation process in detail but elucidates a mechanism, which may be effective throughout shock wave lithotripsy in general. Measurements on model stones in water revealed forces in the range of 370 N, acceleration values of 100,000-200,000 m/s² (≈ 10,000 g) and gained momentum of 3.7 × 10^- 4 kg m/s we consider sufficient to break most human urinary stones. Fracture patterns of repeated identical shock waves show typical features supporting spallation (Hopkinson effect) and the mechanism of momentum transfer. Schlieren and photo-elastic images provide a visual impression of spatial stress in a transparent acrylic glass cylinder, cavitation fields outside and at the surface of the cylinder, which are compatible with the inertia model. The proposed mechanism covers coarse as well as fine fragmentation. Collapsing cavitation bubbles may have an impact on the fragmentation process but although expected, a direct action of micro-jets on sample surfaces could not be detected.

Indications and contraindications for shock wave lithotripsy and how to improve outcomes

For over 35 years shock wave lithotripsy has proven to be an effective, safe and truly minimally invasive option for the treatment of nephrolithiasis. Various technical factors as well as patient selection can impact the success of the procedure. We used published work focusing on outcomes of shock wave lithotripsy, risk of complications, and strategies for improving stone fragmentation to create this review. Multiple patient and technical factors have been found to impact success of treatment. Skin to stone distance, stone density and composition, size and location of the stone within the urinary system all influence stone free rates. A slower rate with a gradual increasing voltage, precise targeting, proper coupling will improve stone fragmentation and decrease risk of complications. The selection of appropriate patients through a shared decision making process and attention to the technical factors that improve stone free rates is key to providing an effective treatment and patient satisfaction.

Trends in the treatment of urinary stone disease in Turkey

Introduction

In this study, a survey was prepared for urologists that asked about their primary choice of treatment for urolithiasis in daily practice and their answers were evaluated.

Methods

The survey was prepared on the Google Docs website and it was sent to 1,016 urologists via email with 752 confirmed deliveries. In addition to the demographic questions about each participant's age, gender, and institution, the survey presented case scenarios focusing on their preferred treatment modalities for distal ureteric, proximal ureteric, and renal calculi. The participating urologists were divided into two groups according to the frequency that they treat urolithiasis patients.

Results

Of the 752 surveys delivered, 211 urologists (28.05%) responded and 204 answered all questions. According to the results, there were no significant differences between the treatment approaches and the other localizations, but there was a statistically significant difference for treatment approaches to lower pole stones between two groups. In response to the question of which stone treatment method was used less frequently, 124 (60.7%) participants answered that they used shock wave lithotripsy less in the last 10 years.

Conclusion

The present study has shown that while the management of renal and ureteric calculi by Turkish urologists is highly varied, the overall treatment patterns are in accordance with the European Association of Urology guidelines. However, similar to the global trend extracorporeal shock wave lithotripsy is less preferred by Turkish urologists.

Discrete Boltzmann trans-scale modeling of high-speed compressible flows

We present a general framework for constructing trans-scale discrete Boltzmann models (DBMs) for high-speed compressible flows ranging from continuum to transition regime. This is achieved by designing a higher-order discrete equilibrium distribution function that satisfies additional nonhydrodynamic kinetic moments. To characterize the thermodynamic nonequilibrium (TNE) effects and estimate the condition under which the DBMs at various levels should be used, two measures are presented: (i) the relative TNE strength, describing the relative strength of the (N+1)th order TNE effects to the Nth order one; (ii) the TNE discrepancy between DBM simulation and relevant theoretical analysis. Whether or not the higher-order TNE effects should be taken into account in the modeling and which level of DBM should be adopted is best described by the relative TNE intensity and/or the discrepancy rather than by the value of the Knudsen number. As a model example, a two-dimensional DBM with 26 discrete velocities at Burnett level is formulated, verified, and validated.

Shock wave-induced permeabilization of mammalian cells

Controlled permeabilization of mammalian cell membranes is fundamental to develop gene and cell therapies based on macromolecular cargo delivery, a process that emerged against an increasing number of health afflictions, including genetic disorders, cancer and infections. Viral vectors have been successfully used for macromolecular delivery; however, they may have unpredictable side effects and have been limited to life-threatening cases. Thus, several chemical and physical methods have been explored to introduce drugs, vaccines, and nucleic acids into cells. One of the most appealing physical methods to deliver genes into cells is shock wave-induced poration. High-speed microjets of fluid, emitted due to the collapse of microbubbles after shock wave passage, represent the most significant mechanism that contributes to cell membrane poration by this technique. Herein, progress in shock wave-induced permeabilization of mammalian cells is presented. After covering the main concepts related to molecular strategies whose applications depend on safer drug delivery methods, the physics behind shock wave phenomena is described. Insights into the use of shock waves for cell membrane permeation are discussed, along with an overview of the two major biomedical applications thereof-i.e., genetic modification and anti-cancer shock wave-assisted chemotherapy. The aim of this review is to summarize 30 years of data showing underwater shock waves as a safe, noninvasive method for macromolecular delivery into mammalian cells, encouraging the development of further research, which is still required before the introduction of this promising tool into clinical practice.

[Extracorporeal shock wave lithotripsy]

Interventional treatment of stones essentially consists of three treatment modalities. Extracorporeal shockwave lithotripsy (ESWL), in addition to uterorenoscopy (URS) and percutaneous nephrolitholapaxy (PCNL) is an essential treatment pillar and is the only noninvasive therapy option for the treatment of urinary stones. After a long period of ESWL being the leading choice in stone treatment, the number of SWL interventions diminished in recent years in favor of the other two treatment modalities (URS and PCNL). This article describes the indications, surgical technique and management of complications of SWL.

How can and should we optimize extracorporeal shockwave lithotripsy?

It is well recognized that the popularity of extracorporeal shock wave lithotripsy (SWL), despite its non-invasive character, has decreased during recent years. This is partly explained by the technological achievements in endoscopy and urologists’ enthusiasm for such procedures. Another explanation is that many urologists have been insufficiently successful with SWL. The latter effect might to some extent be a result of the performance of the lithotripter used, but in too many cases, it is evident that the principles of how shock wave lithotripsy should be carried out are poorly applied. The purpose of this article is to emphasize some important aspects on how SWL best should be used. Based on decades of experience, it stands to reason that success with SWL does not come automatically and attention has to be paid to all details of this technique.

Robot-assisted flexible ureteroscopy: an update

The role of flexible ureteroscopy (FURS) in the management of nephrolithiasis has increased due to the improved armamentarium. However, FURS still represents a challenging technique limiting its diffusion. Similar to previous experiences in laparoscopy, recently developed robotic devices may significantly compensate for the ergonomic deficiencies of FURS. Based on a short description of the history of robotic devices for laparoscopy, this article summarizes all current developments of robotic FURS. In 2008, robotic FURS was first reported using the Sensei-Magellan system designed for interventional cardiology. However, with this device the ureteroscope was only passively manipulated, which represented the main reason why this project has been discontinued after 18 clinical cases. Avicenna Roboflex™ was especially developed for FURS. It consists of a surgeon's console and manipulator of a flexible ureterorenoscope. The console provides an adjustable seat with armrests and two manipulators of the endoscope: the right wheel enables deflection and the left horizontal joystick allows rotation as well as advancing and retracting the instrument. The speed of rotation and advancement can be regulated at the screen of the console. Using the IDEAL system for evaluation of new robotic devices, safety and efficacy of the system could be demonstrated in two multi-centric studies providing significant improved ergonomics for the surgeon (IDEAL stage 1 and 2). Future studies are necessary to determine the final role of robotic FURS.

Evaluation of an experimental electrohydraulic discharge device for extracorporeal shock wave lithotripsy: Pressure field of sparker array

In this paper, an extracorporeal shock wave source composed of small ellipsoidal sparker units is described. The sparker units were arranged in an array designed to produce a coherent shock wave of sufficient strength to fracture kidney stones. The objective of this paper was to measure the acoustical output of this array of 18 individual sparker units and compare this array to commercial lithotripters. Representative waveforms acquired with a fiber-optic probe hydrophone at the geometric focus of the sparker array indicated that the sparker array produces a shock wave (P⁺ ∼40-47 MPa, P^- ∼2.5-5.0 MPa) similar to shock waves produced by a Dornier HM-3 or Dornier Compact S. The sparker array's pressure field map also appeared similar to the measurements from a HM-3 and Compact S. Compared to the HM-3, the electrohydraulic technology of the sparker array produced a more consistent SW pulse (shot-to-shot positive pressure value standard deviation of ±4.7 MPa vs ±3.3 MPa).

Ultrasound-Induced Bubble Clusters in Tissue-Mimicking Agar Phantoms

Therapeutic ultrasound can drive bubble activity that damages soft tissues. To study the potential mechanisms of such injury, transparent agar tissue-mimicking phantoms were subjected to multiple pressure wave bursts of the kind being considered specifically for burst wave lithotripsy. A high-speed camera recorded bubble activity during each pulse. Various agar concentrations were used to alter the phantom's mechanical properties, especially its stiffness, which was varied by a factor of 3.5. However, the maximum observed bubble radius was insensitive to stiffness. During 1000 wave bursts of a candidate burst wave lithotripsy treatment, bubbles appeared continuously in a region that expanded slowly, primarily toward the transducer. Denser bubble clouds are formed at higher pulse repetition frequency. The specific observations are used to inform the incorporation of damage mechanisms into cavitation models for soft materials.

Multiphase fluid-solid coupled analysis of shock-bubble-stone interaction in shockwave lithotripsy

A novel multiphase fluid-solid-coupled computational framework is applied to investigate the interaction of a kidney stone immersed in liquid with a lithotripsy shock wave (LSW) and a gas bubble near the stone. The main objective is to elucidate the effects of a bubble in the shock path to the elastic and fracture behaviors of the stone. The computational framework couples a finite volume 2-phase computational fluid dynamics solver with a finite element computational solid dynamics solver. The surface of the stone is represented as a dynamic embedded boundary in the computational fluid dynamics solver. The evolution of the bubble surface is captured by solving the level set equation. The interface conditions at the surfaces of the stone and the bubble are enforced through the construction and solution of local fluid-solid and 2-fluid Riemann problems. This computational framework is first verified for 3 example problems including a 1D multimaterial Riemann problem, a 3D shock-stone interaction problem, and a 3D shock-bubble interaction problem. Next, a series of shock-bubble-stone-coupled simulations are presented. This study suggests that the dynamic response of a bubble to LSW varies dramatically depending on its initial size. Bubbles with an initial radius smaller than a threshold collapse within 1 μs after the passage of LSW, whereas larger bubbles do not. For a typical LSW generated by an electrohydraulic lithotripter (p_max  = 35.0MPa, p_min  =- 10.1MPa), this threshold is approximately 0.12mm. Moreover, this study suggests that a noncollapsing bubble imposes a negative effect on stone fracture as it shields part of the LSW from the stone. On the other hand, a collapsing bubble may promote fracture on the proximal surface of the stone, yet hinder fracture from stone interior.

Low-intensity Extracorporeal Shock Wave Therapy for Erectile Dysfunction: A Systematic Review and Meta-analysis

OBJECTIVE

To assess the efficacy of low-energy extracorporeal shock wave therapy (LI-ESWT) for erectile dysfunction (ED), a systematic review and meta-analysis was undertaken.

METHODS

A comprehensive search of the PubMed, Cochrane Register, and Embase databases to March 2017 was performed for randomized controlled trials reporting on patients with ED treated with LI-ESWT. The International Index of Erectile Function (IIEF) and the Erection Hardness Score (EHS) were the most commonly used tools to evaluate the therapeutic efficacy of LI-ESWT.

RESULTS

There were 9 studies including 637 patients from 2005 to 2017. The meta-analysis revealed that LI-ESWT could significantly improve IIEF (mean difference [MD]: 2.54; 95% confidence interval [CI], 0.83-4.25; P = .004) and EHS (risk difference [RD]: 0.16; 95% CI, 0.03-0.28; P = .01). Therapeutic efficacy could last at least 3 months (MD: 4.15; 95% CI, 1.40-6.90; P = .003). Lower energy density (0.09 mJ/mm², MD: 4.14; 95% CI, 0.87-7.42; P = .01) increased the number of pulses (3000 pulses per treatment, MD: 5.11; 95% CI, 3.18-7.05, P < .0001) and shorter total treatment courses (<6 weeks, MD: 3.73; 95% CI, 0.54-6.93; P = .02) resulted in better therapeutic efficacy.

CONCLUSION

These studies suggest that LI-ESWT could significantly improve the IIEF and EHS of patients with ED. The publication of robust evidence from additional randomized controlled trials and longer-term follow-up would provide more confidence regarding the use of LI-ESWT for patients with ED.

Does Previous Open Renal Stone Surgery Affect the Outcome of Extracorporeal Shockwave Lithotripsy Treatment in Adults with Renal Stones?

PURPOSE

To evaluate the effects of previous ipsilateral open renal stone surgery (ORSS) on outcomes of extracorporeal shockwave lithotripsy (SWL) in adults with renal stones.

MATERIALS AND METHODS

A total of 2097 renal units with renal stones underwent SWL treatment at our institution between March 1997 and February 2013. One thousand eight hundred thirty-nine (87.7%) of these had no history of ORSS and were categorized as group 1, and 258 (12.3%) patients having history of ipsilateral ORSS were categorized as group 2. Characteristics of patients, stone and treatment, stone-free, and complications rates were documented in detail and compared in each group. These groups were also subclassified into four subgroups according to the stone location.

RESULTS

The stone-free rates were statistically higher in group 1 than group 2 (73.2% and 61.6%, respectively). There were no differences between groups regarding the complications and steinstrasse. The stone-free rate of SWL for stones located at lower calix has significant difference according to groups 1 and 2 (64% vs 48.4%, p = 0.001). Logistic regression analysis showed that history of ORSS increased SWL failure rate 1.39 times.

CONCLUSION

Overall stone-free rates after SWL treatment was found to be significantly lower in patients with the history of ORSS than in patients without, and this finding was significantly prominent for lower calix stones. We believe that retrograde intrarenal surgery or mini- /micro-percutaneous nephrolithotripsy, despite its possible difficulties in accessing due to anatomical changes, might be a good alternative for SWL.

Electromagnetic and Electrohydraulic Shock Wave Lithotripsy-Induced Urothelial Damage: Is There a Difference?

PURPOSE

To evaluate and compare the acute effect of electromagnetic and electrohydraulic extracorporeal shockwave lithotripsy (SWL) on the urothelial layers of kidney and ureter.

MATERIALS AND METHODS

Fifty patients, 29 males (58%) and 21 females (42%), with an average age of 51.68 years (range: 37-70) who underwent SWL application in two different centers were included. Twenty-eight patients (56%) were treated with electrohydraulic and 22 (44%) were treated with electromagnetic lithotripsy. Urinary cytologic examinations were done immediately before and after SWL therapy and 10 days later. The average numbers of epithelial cells, red blood cells (RBC), and myocytes were counted under 40 × magnification.

RESULTS

There were significant differences in the number of epithelial cells and RBC before and after immediate application of SWL: 1.66 and 14.9 cells/field, (p = 0.001), 5.44 and 113.45 cells/field, respectively (p = 0.001). The number of RBC was significantly higher in patients treated with electromagnetic lithotripsy than those treated with electrohydraulic: 141.9 and 93.4 cells/field, respectively (p = 0.02). No myocyte or basement membrane elements were detected in any of the cytologic examinations. Cytologic examinations done after 10 days of SWL therapy revealed recovery of all abnormal cytologic findings.

CONCLUSIONS

The acute increments in the number of epithelial cells and RBC after SWL were statistically significant but it was not permanent. SWL-induced urinary urothelial lesion is limited to the mucosal layer and there was no evidence of damage to the basal membrane or muscle layer. Electromagnetic lithotripsy caused high numbers of RBC than the electrohydraulic device on the postimmediate urine cytologic examination.

[What is the current status of shock wave lithotripsy?]

BACKGROUND

Shock wave lithotripsy (SWL) became the therapy of choice for the majority of patients with urolithiasis early after its introduction in the early 1980s. Since then, SWL remains the only noninvasive therapy modality for the treatment of urinary stones. Although lithotripters became more versatile and affordable-making them available worldwide-indications for SWL have shifted as well. In most western countries, endoscopic techniques took the lead in stone therapy due to high (early) stone-free and better reimbursement rates. Notwithstanding SWL remains the first-line therapy for most intrarenal and many ureteral stones.

PURPOSE

This contemporary review illuminates technical aspects and improvements of lithotripsy over recent years in context with the current guideline recommendations.

RESULTS

Technical advances in lithotripsy such as shock wave generation, focusing, coupling, stone localization and modifications in therapy regimens are reviewed and presented.

CONCLUSIONS

Urologists are recommended to carefully select the appropriate therapy modality for a patient with urolithiasis. A more comprehensive understanding of the physics of shock waves could lead to much better results, thus, endorsing SWL as first-line therapy for urolithiasis instead of contemporary endourology treatment options.

Medical treatment of erectile dysfunction: too many medical prescriptions?

Erectile dysfunction (ED) is a worldwide commonly reported condition; epidemiological data showed a prevalence ranging from 2.3 to 53.4% within different population subsets. In this context, the advent of phosphodiesterase type 5 inhibitors (PDE5is) in the second mid of 1990s has deeply changed the treatment scenario of this bothersome condition. Being user-friendly compounds with an excellent overall safety profile, PDE5is emerged as the first-line treatment for ED, thus overcoming topical alprostadil and intracavernous injections (ICIs). However, available data on treatment-utilization patterns and medical prescriptions of PDE5is showed a range of as wide as 22-78% of patients reporting to purchase PDE5is even without a proper medical prescription. Moreover, an increase in the recreational use of PDE5is among young men has been observed in the last decades, with a worrisome diffusion of potential health-risky behaviours associated with this habit. Indeed, treatment of ED should carefully follow internationally based clinical guidelines to avoid inappropriate drug prescriptions, which may eventually expose treated patients to drug-related side effects. Thereof, a careful assessment of the so-called modifiable and reversible ED risk factors along with a patient-tailored screening for potential contraindications to the treatment itself should be performed in every case. Lastly, although conclusive data still lack, the potential association between life-risky PDE5is side effects (i.e. cardiovascular adverse events, melanoma skin cancer and worsening of prostate cancer outcomes) should be carefully taken into account when counselling patients for ED treatment.

Shockwave lithotripsy: techniques for improving outcomes

OBJECTIVES

Shock wave lithotripsy (SWL) remains the only effective truly non-invasive treatment for nephrolithiasis. While single-treatment success rates may not equal those of ureteroscopy and percutaneous nephrolithotomy, it has an important role to play in the management of stones. In this paper, we outline the latest evidence-based recommendations for maximizing SWL outcomes, while minimizing complications.

MATERIALS AND METHODS

A comprehensive review of the current literature was performed regarding maximizing SWL outcomes.

RESULTS

Several different considerations need to be made regarding patient selection with respect to body habitus, body mass index, anatomical location and underlying urologic abnormalities. Stone composition and stone density (Hounsfield Units) are important prognostic variables. Patient positioning is critical to allow for adequate stone localization with either fluoroscopy or ultrasound. Coupling should be optimized with a low viscosity gel applied to the therapy head first and patient movement should be limited. SWL energy should be increased slowly and shockwave rates of 60 or 90 Hz should be used. Medical expulsive therapy with alpha-blockers after SWL treatment has shown benefit, particularly with stones greater than 10 mm.

CONCLUSION

While single-treatment success rates may not equal those of ureteroscopy or percutaneous nephrolithotomy, with proper patient selection, optimization of SWL technique, and use of adjunctive treatment after SWL, success rates can be maximized while further reducing the already low rate of serious complications. SWL remains an excellent treatment option for calculi even in 2017.

Combining doxorubicin-nanobubbles and shockwaves for anaplastic thyroid cancer treatment: preclinical study in a xenograft mouse model

Anaplastic thyroid cancer is one of the most lethal diseases, and a curative therapy does not exist. Doxorubicin, the only drug approved for anaplastic thyroid cancer treatment, has a very low response rate and causes numerous side effects among which cardiotoxicity is the most prominent. Thus, doxorubicin delivery to the tumor site could be an import goal aimed to improve the drug efficacy and to reduce its systemic side effects. We recently reported that, in human anaplastic thyroid cancer cell lines, combining doxorubicin-loaded nanobubbles with extracorporeal shock waves, acoustic waves used in lithotripsy and orthopedics without side effects, increased the intracellular drug content and in vitro cytotoxicity. In the present study, we tested the efficacy of this treatment on a human anaplastic thyroid cancer xenograft mouse model. After 21 days, the combined treatment determined the greatest drug accumulation in tumors with consequent reduction of tumor volume and weight, and an extension of the tumor doubling time. Mechanistically, the treatment induced tumor apoptosis and decreased cell proliferation. Finally, although doxorubicin caused the increase of fibrosis markers and oxidative stress in animal hearts, loading doxorubicin into nanobubbles avoided these effects preventing heart damage. The improvement of doxorubicin anti-tumor effects together with the prevention of heart damage suggests that the combination of doxorubicin-loaded nanobubbles with extracorporeal shock waves might be a promising drug delivery system for anaplastic thyroid cancer treatment.

In Situ Activation of Penile Progenitor Cells With Low-Intensity Extracorporeal Shockwave Therapy

BACKGROUND

We previously reported that progenitor cells, or stem cells, exist within penile tissue. We hypothesized that acoustic wave stimulation by low-intensity extracorporeal shockwave therapy (Li-ESWT) would activate local stem or progenitor cells within the penis, producing regenerative effects.

AIMS

To study the feasibility of in situ penile progenitor cell activation by Li-ESWT.

METHODS

We performed a cohort analysis of young and middle-age male Sprague-Dawley rats treated with 5-ethynyl-2'-deoxyuridine (EdU) pulse followed by Li-ESWT. In addition, Li-ESWT was applied to cultured Schwann cells and endothelial cells to study the molecular mechanism involved in cell proliferation. Thirty minutes before Li-ESWT, each rat received an intraperitoneal injection of EdU. Li-ESWT was applied to the penis at very low (0.02 mJ/mm² at 3 Hz for 300 pulses) or low (0.057 mJ/mm² at 3 Hz for 500 pulses) energy levels. The endothelial and Schwann cells were treated with very low energy (0.02 mJ/mm² at 3 Hz for 300 pulses) in vitro.

OUTCOMES

At 48 hours or 1 week after Li-ESWT, penile tissues were harvested for histologic study to assess EdU⁺ and Ki-67⁺ cells, and cell proliferation, Ki-67 expression, Erk1/2 phosphorylation, translocation, and angiogenesis were examined in cultured Schwann and endothelial cells after Li-ESWT.

RESULTS

Li-ESWT significantly increased EdU⁺ cells within penile erectile tissues (P < .01) at 48 hours and 1 week. There were more cells activated in young animals than in middle-age animals, and the effect depended on dosage. Most activated cells were localized within subtunical spaces. In vitro studies indicated that Li-ESWT stimulated cell proliferation through increased phosphorylation of Erk1/2.

CLINICAL TRANSLATION

The present results provide a possible explanation for the clinical benefits seen with Li-ESWT.

STRENGTHS AND LIMITATIONS

The main limitation of the present project was the short period of study and the animal model used. Li-ESWT could be less effective in improving erectile function in old animals because of the decreased number and quality of penile stem or progenitor cells associated with aging.

CONCLUSION

Li-ESWT activation of local penile progenitor cells might be one of the mechanisms that contribute to the beneficial effects of shockwave treatment for erectile dysfunction, which represents a non-invasive alternative to exogenous stem cell therapy. Lin G, Reed-Maldonado AB, Wang B, et al. In Situ Activation of Penile Progenitor Cells With Low-Intensity Extracorporeal Shockwave Therapy. J Sex Med 2017;14:493-501.