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

Abstract 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.

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1108: Treatment Strategy Improves the in Vivo Stone Comminution Efficiency and Reduces Renal Tissue Injury During Shock Wave Lithotripsy

The Journal of Urology ◽

10.1016/s0022-5347(18)35264-9 ◽

2005 ◽

Vol 173 (4S) ◽

pp. 300-301

Author(s):

Michaella E. Maloney ◽

Pei Zhong ◽

Charles G. Marguet ◽

Yufeng F. Zhou ◽

Jeffrey C. Sung ◽

...

Keyword(s):

Shock Wave ◽

Treatment Strategy ◽

Shock Wave Lithotripsy ◽

Tissue Injury ◽

Renal Tissue

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Calcium Phosphate-Coated Titanium Implants in the Mandible: Limitations of the in vivo Minipig Model

European Surgical Research ◽

10.1159/000513846 ◽

2020 ◽

Vol 61 (6) ◽

pp. 177-187

Author(s):

Till Kämmerer ◽

Tony Lesmeister ◽

Victor Palarie ◽

Eik Schiegnitz ◽

Andrea Schröter ◽

...

Keyword(s):

Calcium Phosphate ◽

Statistical Difference ◽

Surface Modifications ◽

Titanium Implants ◽

In Vivo Model ◽

Implant Surface ◽

Press Fit ◽

Endosseous Implant ◽

Bone To Implant Contact

Introduction: We aimed to compare implant osseointegration with calcium phosphate (CaP) surfaces and rough subtractive-treated sandblasted/acid etched surfaces (SA) in an in vivo minipig mandible model. Materials and Methods: A total of 36 cylindrical press-fit implants with two different surfaces (CaP, n = 18; SA, n = 18) were inserted bilaterally into the mandible of 9 adult female minipigs. After 2, 4, and 8 weeks, we analyzed the cortical bone-to-implant contact (cBIC; %) and area coverage of bone-to-implant contact within representative bone chambers (aBIC; %). Results: After 2 weeks, CaP implants showed no significant increase in cBIC and aBIC compared to SA (cBIC: mean 38 ± 5 vs. 16 ± 11%; aBIC: mean 21 ± 1 vs. 6 ± 9%). Two CaP implants failed to achieve osseointegration. After 4 weeks, no statistical difference between CaP and SA was seen for cBIC (mean 54 ± 15 vs. 43 ± 16%) and aBIC (mean 43 ± 28 vs. 32 ± 6). However, we excluded two implants in each group due to failure of osseointegration. After 8 weeks, we observed no significant intergroup differences (cBIC: 18 ± 9 vs. 18 ± 20%; aBIC: 13 ± 8 vs. 16 ± 9%). Again, three CaP implants and two SA implants had to be excluded due to failure of osseointegration. Conclusion: Due to multiple implant losses, we cannot recommend the oral mandibular minipig in vivo model for future endosseous implant research. Considering the higher rate of osseointegration failure, CaP coatings may provide an alternative to common subtractive implant surface modifications in the early phase post-insertion.

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1H-4 Use of Acoustic Scattering to Monitor Kidney Stone Fragmentation During Shock Wave Lithotripsy

2006 IEEE Ultrasonics Symposium ◽

10.1109/ultsym.2006.197 ◽

2006 ◽

Cited By ~ 3

Author(s):

N. R. Owen ◽

O. A. Sapozhnikov ◽

M. R. Bailey ◽

L. Trusov ◽

L. A. Crum

Keyword(s):

Shock Wave ◽

Kidney Stone ◽

Shock Wave Lithotripsy ◽

Acoustic Scattering ◽

Stone Fragmentation

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Hydrogel Tissue Construct-Based High-Content Compound Screening

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057110388269 ◽

2010 ◽

Vol 16 (1) ◽

pp. 120-128 ◽

Cited By ~ 8

Author(s):

Vy Lam ◽

Tetsuro Wakatsuki

Keyword(s):

Kinase Inhibitor ◽

Physiological Mechanism ◽

Rho Kinase ◽

Assay System ◽

Physiological Status ◽

Multiple Parameters ◽

Compound Screening ◽

Tissue Construct

Current pharmaceutical compound screening systems rely on cell-based assays to identify therapeutic candidates and potential toxicities. However, cells grown on 2D substrata or in suspension do not exhibit the mechanical or physiological properties of cells in vivo. To address this limitation, the authors developed an in vitro, high-throughput, 3D hydrogel tissue construct (HTC)–based assay system to quantify cell and tissue mechanical properties and multiple parameters of physiology. HTC mechanics was quantified using an automated device, and physiological status was assessed using spectroscopy-based indicators that were read on microplate readers. To demonstrate the application of this system, the authors screened 4 test compounds—rotenone (ROT), cytochalasin D (CD), 2,4-dinitrophenol (DNP), and Rho kinase inhibitor (H-1152)—for their ability to modulate HTC contractility without affecting actin integrity, mitochondrial membrane potential (MMP), or viability. All 4 compounds dose-dependently reduced HTC contractility. However, ROT was toxic, DNP dissipated MMP, and CD reduced both intracellular F-actin and viability. H-1152 was found to be the best candidate compound since it reduced HTC contractility with minimal side effects. The authors propose that their HTC-based assay system can be used to screen for compounds that modulate HTC contractility and assess the underlying physiological mechanism(s) of compound activity and toxicity.

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Re: A Comparative Study of Artificial Neural Network and Multivariate Regression Analysis to Analyze Optimum Renal Stone Fragmentation by Extracorporeal Shock Wave Lithotripsy

The Journal of Urology ◽

10.1016/s0022-5347(11)60236-x ◽

2011 ◽

Vol 185 (6) ◽

pp. 2187-2187

Author(s):

Dean Assimos

Keyword(s):

Neural Network ◽

Shock Wave ◽

Artificial Neural Network ◽

Regression Analysis ◽

Multivariate Regression ◽

Shock Wave Lithotripsy ◽

Renal Stone ◽

Multivariate Regression Analysis ◽

Stone Fragmentation ◽

Extracorporeal Shock Wave

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Cortical involvement and leptomeningeal inflammation in myelin oligodendrocyte glycoprotein antibody disease: A three-dimensional fluid-attenuated inversion recovery MRI study

Multiple Sclerosis Journal ◽

10.1177/13524585211034362 ◽

2021 ◽

pp. 135245852110343

Author(s):

Dimitrios Tzanetakos ◽

John S Tzartos ◽

Aigli G Vakrakou ◽

Marianthi Breza ◽

Georgios Velonakis ◽

...

Keyword(s):

Three Dimensional ◽

Median Number ◽

Myelin Oligodendrocyte Glycoprotein ◽

Inversion Recovery ◽

Cortical Lesion ◽

Mri Findings ◽

Meningeal Inflammation ◽

Fluid Attenuated Inversion Recovery ◽

3D Flair

Background: Cortical demyelination and meningeal inflammation have been detected neuropathologically in multiple sclerosis (MS) and recently in myelin oligodendrocyte glycoprotein antibody disease (MOGAD). Objectives: To assess in vivo cortical and leptomeningeal involvement in MOGAD. Methods: We prospectively evaluated 11 MOGAD and 12 relapsing-remitting MS (RRMS) patients combining three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) and 3D-T1-weighted (3D-T1w) sequences at 3-Tesla magnetic resonance imaging (MRI). Leptomeningeal contrast enhancement (LMCE) was assessed on 3D-FLAIR post-gadolinium (3D-FLAIRGd). Cerebral cortical lesions (CCLs) were classified as either intracortical–subpial (IC–SP) or leukocortical (LC). Results: CCLs were present in 8/11 MOGAD and 12/12 RRMS patients, with the number of CCLs being significantly lower in MOGAD (median (interquartile range (IQR)) 3 (0.5–4) vs 12 (4.75–19), p = 0.0032). In MOGAD, IC–SP lesions were slightly more prevalent than LC lesions (2 (0–2.5) vs 1 (0–2), p = 0.6579); whereas in RRMS, IC–SP lesions were less prevalent than LC lesions (3.5 (2.75–5.5) vs 9 (2–12.75), p = 0.27). LMCE was observed in 3/11 MOGAD and 1/12 RRMS patients; MOGAD with LMCE showed an increased median number of CCLs compared with MOGAD without LMCE (8 (4–9) vs 2.5 (0.75–3.25), p = 0.34). No correlation was observed between MOGAD MRI findings and (a) MOGAD duration, (b) serum MOG-immunoglobulin G1 titers, and (c) oligoclonal band presence. Conclusion: We described cortical lesion topography and detected for the first time LMCE using 3D-FLAIRGd sequences in MOGAD patients.

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Mechanics of Stone Fragmentation in Extracorporeal Shock-Wave Lithotripsy

Shock Focussing Effect in Medical Science and Sonoluminescence ◽

10.1007/978-3-662-05161-0_7 ◽

2003 ◽

pp. 151-178

Author(s):

C. J. Chuong

Keyword(s):

Shock Wave ◽

Extracorporeal Shock Wave Lithotripsy ◽

Shock Wave Lithotripsy ◽

Stone Fragmentation ◽

Extracorporeal Shock Wave

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Time sequential prediction of ventricular-vascular interactions

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1986.251.6.h1341 ◽

1986 ◽

Vol 251 (6) ◽

pp. H1341-H1353 ◽

Cited By ~ 1

Author(s):

T. W. Latson ◽

W. C. Hunter ◽

D. Burkhoff ◽

K. Sagawa

Keyword(s):

Peak Pressure ◽

Peak Flow ◽

Impulse Response Function ◽

Internal Resistance ◽

Arterial System ◽

Analytical Technique ◽

Sequential Prediction ◽

Loading Effects ◽

Instantaneous Pressure

A new analytical method (sequential convolution) for describing ventricular-vascular interactions was used to predict instantaneous pressure and flow in four isolated canine left ventricles ejecting into a computer-simulated arterial system. Ventricular pumping ability was described by a load-independent elastance, [E*(t)] combined with a ventricular internal resistance. “Arterial” properties were characterized using a time-based impulse response function that is derived from impedance measurements. Sequential convolution was then used to couple these independent descriptions of ventricular and vascular properties. Predicted pressure-volume trajectories, as well as instantaneous pressures and flows, closely matched the experimental data. Stroke volume, peak pressure, and peak flow were typically within 5% of measured values. This method provides a powerful analytical technique for examining ventricular-vascular interactions and has potential application in evaluating the ventricular-loading effects of more complex in vivo vascular properties.

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