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1814 FACTORS INFLUENCING THE SUCCESSFUL SHOCK WAVE LITHOTRIPSY (SWL) TREATMENT OF RENAL AND URETERIC STONES: TOWARDS A CLINICAL NOMOGRAM
e704
THE JOURNAL OF UROLOGY姞
Vol. 183, No. 4, Supplement, Wednesday, June 2, 2010
table 1 - GFR prior to ESWL (0)
mean ⴞ SD (ml/min/1,73m2 ) 98,7 ⫾ 22,5
after 1. ESWL (1)
97,5 ⫾ 20,6 (p⬍0,08)
after 2. ESWL (2)
93,4 ⫾ 21,1 (p⬍0,01)
table 2 - variable Intercept
regression-coefficient -4.5125
p
0.0317
0.0309
creatinine prior to ESWL GFR prior to ESWL BMI hypertension
0.0446
0.0023
-0.1538
0.0472
1.2910
0.0076
Source of Funding: None
1814 FACTORS INFLUENCING THE SUCCESSFUL SHOCK WAVE LITHOTRIPSY (SWL) TREATMENT OF RENAL AND URETERIC STONES: TOWARDS A CLINICAL NOMOGRAM Joshua D. Wiesenthal*, Daniela Ghiculete, A. Andrew Ray, Steven Pace, R. John D’A Honey, Kenneth T. Pace, Toronto, Canada INTRODUCTION AND OBJECTIVES: Shock wave lithotripsy (SWL) is considered the first line treatment for the majority of patients with renal and ureteric calculi, with success rates for contemporary series varying from 60-90%. Although success is dependent on patient and stone-related factors there are few reliable algorithms predictive of SWL success. We conducted a retrospective analysis of patient and stone-related factors to determine their influence on the success of SWL and develop a comprehensive nomogram to predict SWL outcomes. METHODS: Data from patients treated at the St. Michael’s Hospital Lithotripsy Unit from May 2004 to June 2009 were reviewed. Analysis was restricted to those patients with a pre-treatment noncontrast CT scan conducted at our centre demonstrating a solitary renal or ureteric calculus ⬍ 20 mm in maximal diameter. Successful treatment of renal stones was defined as those patients who were stone free or had asymptomatic, clinically insignificant residual fragments ⬍ 4 mm in diameter three months after a single SWL treatment. Successful treatment of ureteric stones was defined as stone free 2-week post-SWL. Demographic, stone, patient, treatment and follow-up data were collected from a prospective database and review of CT and KUB imaging by two independent urologists and one radiologist. Data was analyzed with logistic regression, Chi square analysis and ANOVA where appropriate. RESULTS: 422 patients (69.7% male) with a mean age of 51.4 years (SD 12.9) and mean BMI 27.0 kg/m2 (SD 4.9) were analyzed. Mean stone size was 78.9 mm2 (SD 77.3) for ureteral stones and 66.1 mm2 (SD 63.2) for renal stones, with 95 (43.6%) of the renal stones located in the lower pole. The single treatment success rates for ureteral and renal stones were 62.3% and 68.8%, respectively. On univariate analysis, predictors of SWL success, regardless of stone location, were age (p⫽0.01), BMI (p⫽0.01), stone size (p⬍0.001), skin-to-stone distance (SSD; p⬍0.001), and CT attenuation (CTHU, p⫽0.003). On multivariate analysis, age ⬎ 60 (OR⫽0.60, p⫽0.011), stone size ⬎ 45 mm2 (OR⫽0.35, p⬍0.001), and SSD ⬎ 110 mm (OR⫽.49, p⬍0.001) remained significant predictors of outcome. CONCLUSIONS: We have identified patient and stone parameters that can reliably predict SWL outcomes for both ureteral and renal stones. This data can be used by clinicians to facilitate optimal treatment-based decisions and provide patients with more accurate singletreatment success rates for SWL that are tailored to patient-specific situations. Source of Funding: None
1815 COUPLING GEL VISCOSITY - A RELEVANT FACTOR FOR EFFICIENT SHOCK WAVE COUPLING IN SWL Thorsten Bergsdorf*, Christian Chaussy, Stefan Thueroff, Munich, Germany INTRODUCTION AND OBJECTIVES: “Dry head” lithotripters perform shock wave coupling mostly with a coupling bellows and ultrasound gel. Air pockets in the contact area between shock wave system and patient’s skin are able to decrease the transfer of shock wave energy considerably and will be a possible factor for poor treatment outcome. Coupling agents with different characteristics (viscosity) were tested in an in vitro setup regarding coupling quality and quantitative influence on stone comminution. METHODS: A test tank with integrated transparent membrane for coupling with the shock wave source was installed on a clinical lithotripter (SIEMENS Lithoskop®). For evaluation of the coupling quality (quantity of air bubbles in the contact area) the coupling process was filmed with the use of different ultrasound gels (low, medium and high viscosity, gel disc). In a second setup, artificial stones (AST0118) placed in a mesh with 2 mm were fragmented (60 SW/min., E⫹12mm: 31 mJ), to assess the quantitative influence of different gel viscosity on disintegration. The number of shock wave pulses, needed for complete fragmentation was the criterion for efficacy. All experiments were performed five times for every coupling agent. RESULTS: The quality of coupling was varying over a wide range, whereas the gel disc and gel of low viscosity achieved an air pocket free coupling. Gel with medium and high viscosity in contrast showed a poor coupling quality with multiple bubbles in the coupling area. The disintegration test reflected comparable results (see table). CONCLUSIONS: Our in vitro findings indicate, that air pockets within the coupling area deteriorate stone breakage siginificantly. The selection of a proper coupling medium (gel disc or gel with low viscosity) or the accurate removal of air bubbles in the coupling area plays a key role for efficient SWL therapy. quantitative impact of different gels gel disk (SIEMENS) gel with low viscosity (8780 mPas)
av. SW-number 147
av. SW-energy 4,5 J
168
5,2 J
gel with medium viscosity (24584 mPas) without manual removal of air bubbles
424
13 J
with manual removal of air bubbles
168
5,2 J
gel with high viscosity (40244 mPas) without manual removal of air bubbles
264
8,1 J
with manual removal of air bubbles
187
5,8 J
Source of Funding: None
Bladder Cancer: Invasive/Metastatic Disease III Moderated Poster 53 Wednesday, June 2, 2010
8:00 AM-10:00 AM
1816 EFFECTS OF PRE-OPERATIVE NUTRITIONAL DEFICIENCY ON 90-DAY MORTALITY AND OVERALL SURVIVAL IN PATIENTS UNDERGOING RADICAL CYSTECTOMY FOR BLADDER CANCER Justin Gregg*, Shady Salem, Sam Chang, Peter Clark, Michael Cookson, Rodney Davis, CJ Stimson, Monty Aghazadeh, Joseph Smith, Daniel Barocas, Nashville, TN INTRODUCTION AND OBJECTIVES: Poor preoperative nutritional status may be a risk factor for peri-operative mortality and poor
THE JOURNAL OF UROLOGY姞
Vol. 183, No. 4, Supplement, Wednesday, June 2, 2010
table 1 - GFR prior to ESWL (0)
mean ⴞ SD (ml/min/1,73m2 ) 98,7 ⫾ 22,5
after 1. ESWL (1)
97,5 ⫾ 20,6 (p⬍0,08)
after 2. ESWL (2)
93,4 ⫾ 21,1 (p⬍0,01)
table 2 - variable Intercept
regression-coefficient -4.5125
p
0.0317
0.0309
creatinine prior to ESWL GFR prior to ESWL BMI hypertension
0.0446
0.0023
-0.1538
0.0472
1.2910
0.0076
Source of Funding: None
1814 FACTORS INFLUENCING THE SUCCESSFUL SHOCK WAVE LITHOTRIPSY (SWL) TREATMENT OF RENAL AND URETERIC STONES: TOWARDS A CLINICAL NOMOGRAM Joshua D. Wiesenthal*, Daniela Ghiculete, A. Andrew Ray, Steven Pace, R. John D’A Honey, Kenneth T. Pace, Toronto, Canada INTRODUCTION AND OBJECTIVES: Shock wave lithotripsy (SWL) is considered the first line treatment for the majority of patients with renal and ureteric calculi, with success rates for contemporary series varying from 60-90%. Although success is dependent on patient and stone-related factors there are few reliable algorithms predictive of SWL success. We conducted a retrospective analysis of patient and stone-related factors to determine their influence on the success of SWL and develop a comprehensive nomogram to predict SWL outcomes. METHODS: Data from patients treated at the St. Michael’s Hospital Lithotripsy Unit from May 2004 to June 2009 were reviewed. Analysis was restricted to those patients with a pre-treatment noncontrast CT scan conducted at our centre demonstrating a solitary renal or ureteric calculus ⬍ 20 mm in maximal diameter. Successful treatment of renal stones was defined as those patients who were stone free or had asymptomatic, clinically insignificant residual fragments ⬍ 4 mm in diameter three months after a single SWL treatment. Successful treatment of ureteric stones was defined as stone free 2-week post-SWL. Demographic, stone, patient, treatment and follow-up data were collected from a prospective database and review of CT and KUB imaging by two independent urologists and one radiologist. Data was analyzed with logistic regression, Chi square analysis and ANOVA where appropriate. RESULTS: 422 patients (69.7% male) with a mean age of 51.4 years (SD 12.9) and mean BMI 27.0 kg/m2 (SD 4.9) were analyzed. Mean stone size was 78.9 mm2 (SD 77.3) for ureteral stones and 66.1 mm2 (SD 63.2) for renal stones, with 95 (43.6%) of the renal stones located in the lower pole. The single treatment success rates for ureteral and renal stones were 62.3% and 68.8%, respectively. On univariate analysis, predictors of SWL success, regardless of stone location, were age (p⫽0.01), BMI (p⫽0.01), stone size (p⬍0.001), skin-to-stone distance (SSD; p⬍0.001), and CT attenuation (CTHU, p⫽0.003). On multivariate analysis, age ⬎ 60 (OR⫽0.60, p⫽0.011), stone size ⬎ 45 mm2 (OR⫽0.35, p⬍0.001), and SSD ⬎ 110 mm (OR⫽.49, p⬍0.001) remained significant predictors of outcome. CONCLUSIONS: We have identified patient and stone parameters that can reliably predict SWL outcomes for both ureteral and renal stones. This data can be used by clinicians to facilitate optimal treatment-based decisions and provide patients with more accurate singletreatment success rates for SWL that are tailored to patient-specific situations. Source of Funding: None
1815 COUPLING GEL VISCOSITY - A RELEVANT FACTOR FOR EFFICIENT SHOCK WAVE COUPLING IN SWL Thorsten Bergsdorf*, Christian Chaussy, Stefan Thueroff, Munich, Germany INTRODUCTION AND OBJECTIVES: “Dry head” lithotripters perform shock wave coupling mostly with a coupling bellows and ultrasound gel. Air pockets in the contact area between shock wave system and patient’s skin are able to decrease the transfer of shock wave energy considerably and will be a possible factor for poor treatment outcome. Coupling agents with different characteristics (viscosity) were tested in an in vitro setup regarding coupling quality and quantitative influence on stone comminution. METHODS: A test tank with integrated transparent membrane for coupling with the shock wave source was installed on a clinical lithotripter (SIEMENS Lithoskop®). For evaluation of the coupling quality (quantity of air bubbles in the contact area) the coupling process was filmed with the use of different ultrasound gels (low, medium and high viscosity, gel disc). In a second setup, artificial stones (AST0118) placed in a mesh with 2 mm were fragmented (60 SW/min., E⫹12mm: 31 mJ), to assess the quantitative influence of different gel viscosity on disintegration. The number of shock wave pulses, needed for complete fragmentation was the criterion for efficacy. All experiments were performed five times for every coupling agent. RESULTS: The quality of coupling was varying over a wide range, whereas the gel disc and gel of low viscosity achieved an air pocket free coupling. Gel with medium and high viscosity in contrast showed a poor coupling quality with multiple bubbles in the coupling area. The disintegration test reflected comparable results (see table). CONCLUSIONS: Our in vitro findings indicate, that air pockets within the coupling area deteriorate stone breakage siginificantly. The selection of a proper coupling medium (gel disc or gel with low viscosity) or the accurate removal of air bubbles in the coupling area plays a key role for efficient SWL therapy. quantitative impact of different gels gel disk (SIEMENS) gel with low viscosity (8780 mPas)
av. SW-number 147
av. SW-energy 4,5 J
168
5,2 J
gel with medium viscosity (24584 mPas) without manual removal of air bubbles
424
13 J
with manual removal of air bubbles
168
5,2 J
gel with high viscosity (40244 mPas) without manual removal of air bubbles
264
8,1 J
with manual removal of air bubbles
187
5,8 J
Source of Funding: None
Bladder Cancer: Invasive/Metastatic Disease III Moderated Poster 53 Wednesday, June 2, 2010
8:00 AM-10:00 AM
1816 EFFECTS OF PRE-OPERATIVE NUTRITIONAL DEFICIENCY ON 90-DAY MORTALITY AND OVERALL SURVIVAL IN PATIENTS UNDERGOING RADICAL CYSTECTOMY FOR BLADDER CANCER Justin Gregg*, Shady Salem, Sam Chang, Peter Clark, Michael Cookson, Rodney Davis, CJ Stimson, Monty Aghazadeh, Joseph Smith, Daniel Barocas, Nashville, TN INTRODUCTION AND OBJECTIVES: Poor preoperative nutritional status may be a risk factor for peri-operative mortality and poor