13 resultados para Shock-wave Heating

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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This study aims to quantify by intravital microscopy the microhemodynamic response after extracorporeal shock wave application (ESWA) to the physiologic microcirculation of the mouse dorsal skinfold chamber.

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The aim of this study was to investigate if radial extracorporeal shock wave therapy (rESWT) induces new bone formation and to study the time course of ESWT-induced osteogenesis. A total of 4000 impulses of radial shock waves (0.16 mJ/mm²) were applied to one hind leg of 13 New Zealand white rabbits with the contralateral side used for control. Treatment was repeated after 7 days. Fluorochrome sequence labeling of new bone formation was performed by subcutaneous injection of tetracycline, calcein green, alizarin red and calcein blue. Animals were sacrificed 2 weeks (n = 4), 4 weeks (n = 4) and 6 weeks (n = 5) after the first rESWT and bone sections were analyzed by fluorescence microscopy. Deposits of fluorochromes were classified and analyzed for significance with the Fisher exact test. rESWT significantly increased new bone formation at all time points over the 6-week study period. Intensity of ossification reached a peak after 4 weeks and declined at the end of the study. New bone formation was significantly higher and persisted longer at the ventral cortex, which was located in the direction to the shock wave device, compared with the dorsal cortex, emphasizing the dose-dependent process of ESWT-induced osteogenesis. No traumata, such as hemorrhage, periosteal detachment or microfractures, were observed by histologic and radiologic assessment. This is the first study demonstrating low-energy radial shock waves to induce new bone formation in vivo. Based on our results, repetition of ESWT in 6-week intervals can be recommended. Application to bone regions at increased fracture risk (e.g., in osteoporosis) are possible clinical indications.

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OBJECTIVE: To determine via histologic examination and scintigraphy the effect of focused extracorporeal shock wave therapy (ESWT) on normal bone and the bone-ligament interface in horses. ANIMALS: 6 horses without lameness. PROCEDURE: Origins of the suspensory ligament at the metacarpus (35-mm probe depth) and fourth metatarsal bone (5-mm probe depth) were treated twice (days 0 and 16) with 2,000 shocks (energy flux density, 0.15 mJ/mm2). One forelimb and 1 hind limb were randomly treated, and the contralateral limbs served as nontreated controls. Bone scans were performed on days -1 (before ESWT), 3, 16, and 19. Histomorphologic studies of control and treated tissues were performed on day 30. RESULTS: ESWT significantly increased the number of osteoblasts but caused no damage to associated soft tissue structures and did not induce cortical microfractures. A significant correlation between osteoblast numbers and radiopharmaceutical uptake was noticed on lateral views of the hind limb on days 3 and 16 and on caudal views of the forelimb on day 3. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ESWT has the potential to increase osteoblast numbers in horses. The correlation between increased osteoblast numbers and radio-pharmaceutical uptake 3 days and 16 days after the first ESWT suggested that stimulation of osteogenesis occurred soon after ESWT. No damage to bone or the bone-ligament interface should occur at the settings used in this study, and ESWT can therefore be administered safely in horses.

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PURPOSE: We assessed the efficacy of extracorporeal shock wave lithotripsy (ESWL, Dornier Medical Systems, Inc., Marietta, Georgia) for distal ureteral calculi with the HM3 (Dornier Medical Systems, Inc.) lithotriptor. MATERIALS AND METHODS: A total of 585 consecutive patients with distal ureteral calculi were treated with ESWL using an unmodified HM3 lithotriptor. Of these patients 67 referred for treatment only for whom no followup was available were excluded from further analysis. The remaining 518 cases were followed until they were radiologically documented to be stone-free or considered treatment failures. Before ESWL additional procedures were performed in 144 patients, including stone push back, ureteral catheter or Double-J (Medical Engineering Corp., New York, New York) stent placement, percutaneous nephrostomy, ureteral endoscopic maneuvers or stone basket manipulation. A total of 374 patients needed no preliminary treatment before ESWL. RESULTS: Of the 518 patients 469 (91%) were successfully treated with 1 ESWL session, while 49 (9%) needed 2 or 3. Manipulation after ESWL was performed in 22 cases, including stent placement, percutaneous nephrostomy, ureteral endoscopic stone removal and a stone basket procedure. On day 1 after ESWL 327 patients (63%) were stone-free, 158 (30%) had less than 5 mm. fragments and 33 (7%) had more than 5 mm. fragments. At 3 months the stone-free rate increased to 97%. CONCLUSIONS: These data show that ESWL for distal ureteral calculi with the powerful unmodified HM3 lithotriptor has a high success rate with a low rate of minimally traumatic manipulations before and after intervention. Results in terms of the re-treatment and stone-free rates are superior to those of any other second or third generation lithotriptor and comparable to the results of the best ureteroscopic series.

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Background: Cardiac shock wave therapy (CSWT) delivered to the myocardium increases capillary density and regional myocardial blood flow in animal experiments. In addition, nonenzymatic nitric oxide production and the upregulation of vascular growth factor's mRNA by CSWT have been described. The aim of the study was therefore to test its potential to relieve symptoms in patients with chronic stable angina pectoris. Methods: Twenty-one patients (mean age 68.2 ± 8.3 years, 19 males) with chronic refractory angina pectoris and evidence of inducible myocardial ischemia during MIBI-SPECT imaging, were randomized into a treatment (n = 11) and a placebo arm (n = 10). The region of exercise-induced ischemia was treated with echocardiographic guidance during nine sessions over a period of 3 months. One session of CSWT consisted of 200 shots/spot (9--12 spots/session) with an energy intensity of 0.09 mJ/mm2. In the control group acoustic simulation was performed without energy application. Medication was kept unchanged during the whole treatment period. Results: In the treatment group, symptoms improved in 9/11 patients, and the ischemic threshold, determined by cardiopulmonary exercise stress testing, increased from 80 ± 28 to 95 ± 28 W (P= 0.036). In the placebo arm, only 2/10 patients reported an improvement and the ischemic threshold remained unchanged (98 ± 23 to 107 ± 23 W; P= 0.141). The items “physical functioning” (P= 0.043), “general health perception” (P= 0.046), and “vitality” (P= 0.035) of the SF-36 questionnaire significantly improved in the treatment arm, whereas in the placebo arm, no significant change was noted. Neither arrhythmias, troponin rise nor complications were observed during treatment. Conclusions: This placebo controlled trial shows a significant improvement in symptoms, quality of life parameters and ischemic threshold during exercise in patients with chronic refractory angina pectoris treated with CSWT. Thus, CSWT represents a new option for the treatment of patients with refractory AP.

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Extracorporeal shock waves are defined as a sequence of sonic pulses characterized by high peak pressure over 100 MPa, fast pressure rise, and short lifecycle. In the 1980s extracorporeal shock wave lithotripsy (ESWL) was first used for the treatment of urolithiasis. Orthopedic surgeons use extracorporeal shock wave therapy (ESWT) to treat non-union fractures, tendinopathies and osteonecrosis. The first application of ESWT in dermatology was for recalcitrant skin ulcers. Several studies in the last 10 years have shown that ESWT promotes angiogenesis, increases perfusion in ischemic tissues, decreases inflammation, enhances cell differentiation and accelerates wound healing. We successfully treated a non-healing chronic venous leg ulcer with ESWT. Furthermore we observed an improvement of the lymphatic drainage after application of ESWT. We are confident that ESWT is a non-invasive, practical, safe and efficient physical treatment modality for recalcitrant leg ulcers.

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PURPOSE Management of ureteral stones remains controversial. To determine whether optimizing extracorporeal shock wave lithotripsy (ESWL) delivery rates improves treatment of solitary ureteral stones, we compared outcomes of two SW delivery rates in a prospective, randomized trial. MATERIALS AND METHODS From July 2010 to October 2012, 254 consecutive patients were randomized to undergo ESWL at SW delivery rates of either 60 pulses (n=130) or 90 pulses (n=124) per min. The primary endpoint was stone-free rate at 3-month follow-up. Secondary endpoints included stone disintegration, treatment time, complications, and the rate of secondary treatments. Descriptive statistics were used to compare endpoints between the two groups. Adjusted odds ratios and 95% confidence intervals were calculated to assess predictors of success. RESULTS The stone-free rate at 3 months was significantly higher in patients who underwent ESWL at a SW delivery rate of 90 pulses per min than in those receiving 60 pulses (91% vs. 80%, p=0.01). Patients with proximal and mid-ureter stones, but not those with distal ureter stones, accounted for the observed difference (100% vs. 83%; p=0.005; 96% vs. 73%, p=0.03; and 81% vs. 80%, p=0.9, respectively). Treatment time, complications, and the rate of secondary treatments were comparable between the two groups. In multivariable analysis, SW delivery rate of 90 pulses per min, proximal stone location, stone density, stone size and the absence of an indwelling JJ stent were independent predictors of success. CONCLUSIONS Optimization of ESWL delivery rates can achieve excellent results for ureteral stones.

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BACKGROUND Painful cutaneous injection site reactions may hamper treatment with interferon β (IFN-β) and glatiramer acetate (GA) in multiple sclerosis (MS) patients. OBJECTIVE To maintain therapy adherence, efficient therapeutic modalities for these subcutaneous inflammatory lesions are urgently needed. We tested the application of local extracorporeal shock wave therapy (ESWT). METHODS We applied 5 sessions of ESWT to 8 patients suffering from MS who had developed painful panniculitis at the injection sites of either IFN-β or GA. Clinical outcomes, i.e. pain reduction and regression of induration, were assessed 3 and 6 months after completion of the ESWT using a visual analogue score. RESULTS All patients showed both significant pain reduction and reduction of the skin induration in the treated lesions, while in untreated control lesions there was no improvement. CONCLUSION ESWT proved to be a non-invasive, safe and efficient physical treatment modality for injection-induced painful cutaneous side effects of disease-modifying drugs in MS. © 2014 S. Karger AG, Basel.

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The aim of this study was to determine if extracorporeal shock wave therapy (ESWT) in vivo affects the structural integrity of articular cartilage. A single bout of ESWT (1500 shock waves of 0.5 mJ/mm(2)) was applied to femoral heads of 18 adult Sprague-Dawley rats. Two sham-treated animals served as controls. Cartilage of each femoral head was harvested at 1, 4, or 10 weeks after ESWT (n = 6 per treatment group) and scored on safranin-O-stained sections. Expression of tenascin-C and chitinase 3-like protein 1 (Chi3L1) was analyzed by immunohistochemistry. Quantitative real-time polymerase chain reaction (PCR) was used to examine collagen (II)alpha(1) (COL2A1) expression and chondrocyte morphology was investigated by transmission electron microscopy no changes in Mankin scores were observed after ESWT. Positive immunostaining for tenascin-C and Chi3L1 was found up to 10 weeks after ESWT in experimental but not in control cartilage. COL2A1 mRNA was increased in samples 1 and 4 weeks after ESWT. Alterations found on the ultrastructural level showed expansion of the rough-surfaced endoplasmatic reticulum, detachment of the cell membrane and necrotic chondrocytes. Extracorporeal shock waves caused alterations of hyaline cartilage on a molecular and ultrastructural level that were distinctly different from control. Similar changes were described before in the very early phase of osteoarthritis (OA). High-energy ESWT might therefore cause degenerative changes in hyaline cartilage as they are found in initial OA.

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Percutaneous nephrolithotomy (PCNL) for the treatment of renal stones and other related renal diseases has proved its efficacy and has stood the test of time compared with open surgical methods and extracorporal shock wave lithotripsy. However, access to the collecting system of the kidney is not easy because the available intra-operative image modalities only provide a two dimensional view of the surgical scenario. With this lack of visual information, several punctures are often necessary which, increases the risk of renal bleeding, splanchnic, vascular or pulmonary injury, or damage to the collecting system which sometimes makes the continuation of the procedure impossible. In order to address this problem, this paper proposes a workflow for introduction of a stereotactic needle guidance system for PCNL procedures. An analysis of the imposed clinical requirements, and a instrument guidance approach to provide the physician with a more intuitive planning and visual guidance to access the collecting system of the kidney are presented.

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BACKGROUND Renal damage is more frequent with new-generation lithotripters. However, animal studies suggest that voltage ramping minimizes the risk of complications following extracorporeal shock wave lithotripsy (SWL). In the clinical setting, the optimal voltage strategy remains unclear. OBJECTIVE To evaluate whether stepwise voltage ramping can protect the kidney from damage during SWL. DESIGN, SETTING, AND PARTICIPANTS A total of 418 patients with solitary or multiple unilateral kidney stones were randomized to receive SWL using a Modulith SLX-F2 lithotripter with either stepwise voltage ramping (n=213) or a fixed maximal voltage (n=205). INTERVENTION SWL. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS The primary outcome was sonographic evidence of renal hematomas. Secondary outcomes included levels of urinary markers of renal damage, stone disintegration, stone-free rate, and rates of secondary interventions within 3 mo of SWL. Descriptive statistics were used to compare clinical outcomes between the two groups. A logistic regression model was generated to assess predictors of hematomas. RESULTS AND LIMITATIONS Significantly fewer hematomas occurred in the ramping group(12/213, 5.6%) than in the fixed group (27/205, 13%; p=0.008). There was some evidence that the fixed group had higher urinary β2-microglobulin levels after SWL compared to the ramping group (p=0.06). Urinary microalbumin levels, stone disintegration, stone-free rate, and rates of secondary interventions did not significantly differ between the groups. The logistic regression model showed a significantly higher risk of renal hematomas in older patients (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00-1.05; p=0.04). Stepwise voltage ramping was associated with a lower risk of hematomas (OR 0.39, 95% CI 0.19-0.80; p=0.01). The study was limited by the use of ultrasound to detect hematomas. CONCLUSIONS In this prospective randomized study, stepwise voltage ramping during SWL was associated with a lower risk of renal damage compared to a fixed maximal voltage without compromising treatment effectiveness. PATIENT SUMMARY Lithotripsy is a noninvasive technique for urinary stone disintegration using ultrasonic energy. In this study, two voltage strategies are compared. The results show that a progressive increase in voltage during lithotripsy decreases the risk of renal hematomas while maintaining excellent outcomes. TRIAL REGISTRATION ISRCTN95762080.