Extracorporeal Shockwave Lithotripsy 2015 Geert G. TAILLY Urology Arena Bern, December 04, 2015
The Integrated Endourology Concept The basis of modern stone management remains a judicious combination of both ESWL and Endourology (URS, PNL, RIRS), each individual treatment tailored to the stone and the patient : Integrated Endourology
Guidelines : EAU and AUA RENAL stones EAU Guidelines Türk et al. : EAU Guidelines on Urolithiasis 2015 Renal pelvis Upper & Middle calyx > 20 mm 1. PNL 2. RIRS or ESWL 10 20 mm ESWL or Endourology (RIRS/PNL) < 1 mm 1. ESWL or RIRS 2. PNL Joint AUA/EAU Guidelines Preminger et al., J. Urol., Vol 178, 2418-2434, Dec 2007 Lower Pole Calyx (LPC) Unfavourable factors for ESWL NO : ESWL or Endourology YES : 1. Endourology 2. ESWL URETERAL stones FIRST choice SECOND choice Proximal ureter < 10 mm ESWL URS Proximal ureter > 10 mm Distal ureter < 10 mm ESWL or URS ESWL or URS Distal ureter > 10 mm URS ESWL
Guidelines : EAU and AUA RENAL stones EAU Guidelines Türk et al. : EAU Guidelines on Urolithiasis 2015 Renal pelvis Upper & Middle calyx > 20 mm 1. PNL 2. RIRS or ESWL 10 20 mm ESWL or Endourology (RIRS/PNL) < 1 mm 1. ESWL or RIRS 2. PNL - Kidney Joint AUA/EAU stones Guidelines > 20 mm Preminger et al., J. Urol., Vol 178, 2418-2434, Dec 2007 Lower Pole Calyx (LPC) Unfavourable factors for ESWL NO : ESWL or Endourology YES : 1. Endourology 2. ESWL URETERAL stones FIRST choice SECOND choice Proximal ureter < 10 mm ESWL URS Proximal ureter > 10 mm ESWL remains 1st choice except for : - Lower pole stones 10-20 mm with unfavourable factors for ESWL - Distal ureteral stones > 10 mm ESWL or URS Distal ureter < 10 mm ESWL or URS Distal ureter > 10 mm URS ESWL
The Integrated Endourology Concept Dedicated Endouro Nursing Staff Multifunctional Lithotripter : Dornier Gemini Large Endourology Suite Disposables Efficiency Quality Turnover Endoscopic instruments
Modern stone management Versatile system for stone disease management ESWL Endourology SW-source Efficacy and Safety Flexible SW coupling Access is a key factor Patient access Equipment access (light source, laser, ) Powerful and versatile imaging (US and X-ray) System with integrated Lithotripter and Urotable functions Optimize workflow and results in Endourology and ESWL
The Lithotriptors From dedicated lithotriptor to Multifunctional Workstation
The Lithotriptors From dedicated lithotriptor to Multifunctional Workstation ESWL Endourology
Technical developments : URO-TABLE function Dornier GEMINI Max. Patient weight : 250 kg Accessibility over 360 Lowest level : 71 cm (Anti-) Trendelenburg isocentric Satellite arms with flatscreens, lightsource,
Technical developments : Imaging Versatility in imaging modality : Simultaneous use of X-ray and US
Technical developments : Imaging Versatility in C-arm movements : Orbital and C-C +/- movements
Technical developments : Imaging From Image Intensifier to FPD Improvements in image quality by improvements of the imaging chain : Flat Panel Detector (FPD)
Technical developments : SW-source Powerful SW-source: EMSE 220F-XXP * outperforms the HM3 or any other spark gap source * Dornier GEMINI
Technical developments : SW-source Dornier GEMINI : SW-sources EMSE 220F-XXP EMSE 220F-XXP HP Diameter (mm) 220 220 Aperture 73 66 Max. Treatment Depth 150 170 Focus size (mm x mm) 63 x 5 89 x 6
Technical developments : SW-source Increased penetration depth : obese patients
Technical developments : SW-source Versatile coupling of therapy head : All patients SUPINE Kidney UNDER table Proximal ureter UNDER table Distal ureter ABOVE table
Technical developments : OptiCouple patient SWL focus + transparent water cushion SWL lens Video camera EMSE
Technical developments : The Future Modifications of SW geometry : large focus-low pressure? BWL : Burst Wave Lithotripsy? Modifications of the p- phase of the SW : pronounced effect on bubble cavitation Techniques to rapidly eliminate cavitation bubbles as soon as they have formed Christian Chaussy & Hans-Göran Tiselius. Engineering better lithotripters. Ahead of publication
Mechanisms of stone disintegration Hopkinson Effect Shear Forces Quasistatic Squeezing Cavitation Dynamic Fatigue Stone Disintegration
Cause of side effects : CAVITATION CAVITATION : Bubble dynamics Bubble compression Bubble expansion Bubble collapse
Cause of side effects : CAVITATION CAVITATION : Bubble dynamics Bubble compression Bubble expansion Bubble collapse Bubble collapse in tissue Disruptive tissue effects
The two faces of CAVITATION CAVITATION One of the key mechanisms in stone disintegration Probably the single most important factor in the occurrence of acute post-eswl complications
Cavitation control Subsequent SW impaired by persisting cavitation bubbles from previous SW Pre-existing bubbles = cavitation nuclei for consecutive SW forced bubble collapse Reduced stone disintegration Shockwave Path Increased risk of side effects
Cavitation control : Pulse Repetition Frequency (PRF) Higher acoustic energy More cavitation bubbles Generation of cavitation bubbles (Schematically according to Jochle et al. : Phys Med Biol. 1999) Higher PRF
Good clinical practice : SW delivery A slower SW-rate reduces cavitation effects and hence reduces the risk of cavitation induced adverse tissue effects. This in turn improves the efficacy of every single SW hitting the stone, thus improving fragmentation and outcome : better SFR, lower retreatment rate, better EQ. Chacko et al, J. of Urology, Vol 175, April 2006, 1370-1374 Pace et al, J. of Urology, Vol 174, 2005, 595-599 Weizer et al, Urologic Clinics of NA, August 2007, Vol 34, No 3, 375-382 Pishchalnikov et al, BJU Int 2008, 102, 1681-1686 Skolarikos et al, Eur. Urol. 50, 2006, 981-990 Rassweiler et al, Eur. Urol. 59, 2011, 784-796
Good clinical practice : SW delivery A slower SW-rate not only improves outcome, but also improves costeffectiveness and overall efficiency : in a slow rate group total cost per treatment and total mean actual cost proved lower. Vincent Koo et al, BJI Int 2009, Journal compilation 1-5
Good clinical practice : SW delivery Gradually increasing the power output of the lithotriptor ( Voltage stepping or ramping ) improves stone fragmentation and reduces injury to the renal parenchyma. McAteer et al, Paper presented at AUA 2003 Weizer et al, Urologic Clinics of NA, August 2007, Vol 34, No 3, 375-382 Lambert et al, WCE Shanghai 2008, MP15-01 Rassweiler et al, Eur. Urol. 59, 2011, 784-796
Good clinical practice : SW delivery Reduce SW delivery rate (PRF) to 60-80 SW/min according to energy level : Energy level PRF Use voltage stepping. Start with a low-voltage dose of 100-200 SW before starting voltage stepping. Treatment pause of 1-2 mins after an initial dose of ± 200 SW.
Importance of coupling Air bubbles in the coupling area impair energy transfer Monitoring the Coupling of the Lithotripter Therapy Head With Skin During Routine Shock Wave Lithotripsy With a Surveillance Camera. Christian Bohris et al. J. Urol; Vol. 187, 157-163, January 2012.
Importance of coupling Air bubbles in the coupling area impair energy transfer Reduction of disintegration capacity Monitoring the Coupling of the Lithotripter Therapy Head With Skin During Routine Shock Wave Lithotripsy With a Surveillance Camera. Christian Bohris et al. J. Urol; Vol. 187, 157-163, January 2012.
Quality of coupling Optimal coupling in the HM3 : Both patient and SW-source immersed in 1200L of degassed water
Quality of coupling Modern dry head lithotripters : US-gel as an interface
Quality of coupling Several in vitro studies have established that air bubbles in the coupling area significantly affect energy transfer and hence disintegration efficacy. C. Bohris et al., Therapeutic Energy Applications in Urology II, 61-64 C. Bohris et al., J. Urol., Vol 187, 157-163, 2012 Jain et al., Eur Urol, 2007, 51, 1680-1687 Pishchalnikov et al., J. Urol, 2006, 176, 2706-2710 Li G. et al., BJU Int 2012, Vol 110, Issue 116, E871-E877
Quality of coupling The real problem is not to find a coupling medium that efficiently transmits SW energy, but to find a way to avoid the entrapment of air pockets during the coupling process. Li G. et al., BJU Int 2012, Vol 110, Issue 116, E871-E877
Quality of coupling The real problem is not to find a coupling medium that efficiently transmits SW energy, but to find a way to avoid the entrapment of air pockets during the coupling process. Until now it proved impossible however to visually monitor the coupling area between therapy head and patient.
Quality of coupling The real problem is not to find a coupling medium that efficiently transmits SW energy, but to find a way to avoid the entrapment of air pockets during the coupling process. Until now it proved impossible however to visually monitor the coupling area between therapy head and patient. A videocamera in the therapy head allows visually controlled removal of all air bubbles
Optical Coupling Control Dornier Gemini with integrated video camera for coupling monitoring. Air bubbles are removed from the coupling interface by gently swiping a hand between the patient and the inflated water cushion.
OCC : Effects on treatment results Reduction in number of SW : - 25.4% for renal stones - 25.5% for ureteral stones
OCC : Effects on treatment results Reduction in number of SW : - 25.4% for renal stones - 25.5% for ureteral stones Reduction in energy level : - 23.1% for renal stones - 22.5% for ureteral stones
OCC : Effects on treatment results Reduction in number of SW : - 25.4% for renal stones - 25.5% for ureteral stones Reduction in energy level : - 23.1% for renal stones - 22.5% for ureteral stones Reduction in Accumulated Energy (AE) : - 42.9% for renal stones - N/A for ureteral stones
OCC : Effects on treatment results Reduction in number of SW : - 25.4% for renal stones - 25.5% for ureteral stones Reduction in energy level : - 23.1% for renal stones - 22.5% for ureteral stones Reduction in Accumulated Energy (AE) : - 42.9% for renal stones - N/A for ureteral stones Effectiveness Quotients (EQ) comparable
OCC : Effects on treatment results Optical Coupling Control Effects on treatment results RENAL stones URETERAL stones Number of SW -25.4% -25.5% Energy level -23.1% -22.5% Accumulated Energy -42.9% N/A Effectiveness Quotient - Blind coupling - OCC Treatment time -25.4% -25.5% 73 74 75 78
Optical Coupling Control : Conclusions Optically controlled removal of air bubbles in the coupling area significantly reduces the total energy needed to obtain comparable treatment results
Optical Coupling Control : Conclusions Optically controlled removal of air bubbles in the coupling area significantly reduces the total energy needed to obtain comparable treatment results Theoretically this reduction in total energy applied should also reduce the incidence and severity of SW-induced adverse effects
Optical Coupling Control : Conclusions Optically controlled removal of air bubbles in the coupling area significantly reduces the total energy needed to obtain comparable treatment results Theoretically this reduction in total energy applied should also reduce the incidence and severity of SW-induced adverse effects An important step toward better ESWL! Tailly et al., J. Endourol., Vol 28, No 11, 2014, 1368-1373
Optical Coupling Control : Recommendations Use a low viscosity ultrasound gel from a wide mouthed container Apply a thick layer of gel in the center of the water cushion using a wooden kitchen spoon Swipe with hand between water cushion and patient to remove air bubbles ideally with optical control Repeat the above sequence whenever there is a need to reposition the patient
Good clinical practice : Analgesia A good analgesia regimen during ESWL improves outcome. Main parameters in analgesia consumption are : - characteristics of the SW-source, - number and energy level of SW, - stone size and location, - patient s age, sex and origin. Tailly, WCE Shanghai 2008, MP15-09 Chaussy et al, WCE Shanghai 2008, MP15-11
Good clinical practice : MET Medical Expulsive Therapy (MET) : A low dose of 1 -blockers (Alfuzosin, Tamsulosin) can enhance the clearance of stone fragments following ESWL. Kyung-seop Lee et al, WCE Shanghai 2008, MP15-04 Kangping Luo et al, WCE Shanghai 2008, MP15-18 Seitz et al, Eur Urol, 2009, 56, 455-471 Seitz et al, Eur Urol Suppl 2010, 9, 807-813
Good clinical practice : PDI Physical measures can facilitate the clearance of stone fragments from the lower pole : Mechanical percussion : P Diuresis : D Inversion : I 108 patients with lower pole stones < 20mm treated with ESWL : 62.5% clearance for ESWL + PDI 35.4% clearance for ESWL alone Chiong et al. 2005
Special conditions : Emergency ESWL Emergency ESWL of URETERAL stones : eeswl Emergency ESWL within a short interval after a first episode of colic offers : - improved fragmentation - a shorter time to achieve complete stone clearance - increase in SFR - a reduced need for repeat ESWL-sessions - treatment of the renal colic in itself Seitz et al, Eur. Urol., 49, 2006, 1099-1106 Tombal et al, Eur. Urol., 47, 2005, 855-859 Kravchik et al, J. Endourol., 19, 2005, 1-4 McLornan et al, Eur Urol Suppl 2009; 8 : 234 (Abstract)
Special conditions : PEDIATRIC patients Recommendations for the PEDIATRIC patient : Both ESWL and URS are effective : Treatment choices to be based on child s size and urinary tract anatomy. The small size of the pediatric ureter and urethra favors the less invasive approach of ESWL. + Children appear to pass post-eswl fragments more readily than adults. Preminger et al., J. Urol., Vol 178, 2418-2434, Dec 2007
Special conditions : OBESITY ESWL failure correlates with an increased BMI (> 30). (1) SWL in patients with an SSD greater than 10cm is likely to fail. (2) SWL becomes less effective as SSD approaches the focal distance of the lithotriptor (2) (1) Pareek et al, Urology (2005) 65 : 33-36 (2) Pareek et al, Urology (2005) 66 : 941-944 (1) Pareek et al., Urology (2005) 65 : 33-36 (2) Pareek et al., Urology (2005) 66 : 941-944
Special conditions : OBESITY In obese patients the main problem is proper targeting and focussing of the stones Lithotriptors with : - High resolution imaging systems - Versatile coupling of SW-source above and under table - Focal distance up to 17 cm Experienced operators : positioning tricks (1) Pareek et al, Urology (2005) 65 : 33-36 (2) Pareek et al, Urology (2005) 66 : 941-944
Complications of ESWL (Acute) complications following in situ and de novo ESWL of ureteral stones = EXTREMELY RARE
Complications of ESWL (Acute) complications following in situ and de novo ESWL of ureteral stones = EXTREMELY RARE ESWL of renal stones Sepsis 1-2.7% Steinstraβe 4-7% Renal colic 2-4% Symptomatic hematoma < 1%
Good clinical practice in ESWL Complexity of SW-administration is generally underestimated
Good clinical practice in ESWL Complexity of SW-administration is generally underestimated Newer machines are too often misjudged as plug-an-play
Good clinical practice in ESWL Complexity of SW-administration is generally underestimated Newer machines are too often misjudged as plug-an-play Lack of background & training in SWL is often cause of poorer results with modern machines
Good clinical practice in ESWL Complexity of SW-administration is generally underestimated Newer machines are too often misjudged as plug-an-play Lack of background & training in SWL is often cause of poorer results with modern machines Proper training should involve : - an understanding of the basic physics of SW - training in all aspects of SW administration
Good clinical practice in ESWL : TRAINING J. Lingeman (AUA 2010): Good results in ESWL are not only a matter of the technology but also of the technique! G. Tailly (J Endourology, Vol 22 (5), May 2008): The downside of the rapid propagation of more affordable but very powerful SW machines is that newer operators receive little, if any, training and thus may have less experience than the original HM3 users. In addition to technical advances education is one of the key factors in maintaining the value of ESWL in the future!
Good clinical practice in ESWL : TRAINING SWL : The new phoenix? If urologists make use of a more comprehensive understanding of the pathophysiology and the physics of SW, much better results could be achieved in the future. This may lead to a renaissance and encourage SWL as first-line therapy for urolithiasis in times of rapid progression in endoscopic treatment modalities. Andreas Neisius, Michael E. Lipkin, Jens J. Rassweiler, Pei Zhong, Glenn M. Preminger, Thomas Knoll World J. Urol. Published online 01 August 2014
Good clinical practice in ESWL : Caution! Don t underestimate the Force!
Good clinical practice in ESWL Experienced Urologist Internationally accepted guidelines Treatment strategy Precise imaging & targeting / Optimal coupling / Careful monitoring of the entire treatment / Proper device settings Judicious application of SW-energy : Energy dose : just enough to do the job / Voltage stepping / SW-release frequency / Treatment pause
Thank you!