The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsy
BACKGROUND: Outcome of Extracorporeal Shockwave Lithotripsy (SWL) is determined by physical factors that affect stone fragmentation and clearance. PURPOSE: To evaluate the predictive value of the Lithotripsy Table Height (LTH) in SWL outcome. Lithotripsy Table Height (LTH) is a variable that represe...
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| Format: | Article |
| Language: | English |
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Sociedade Brasileira de Urologia
2011-06-01
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| Series: | International Brazilian Journal of Urology |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-55382011000300009 |
| _version_ | 1818481529373851648 |
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| author | Enrique Ossandon Pedro Recabal Cristian Acevedo Jose Miguel Flores Fernando Marchant |
| author_facet | Enrique Ossandon Pedro Recabal Cristian Acevedo Jose Miguel Flores Fernando Marchant |
| author_sort | Enrique Ossandon |
| collection | DOAJ |
| description | BACKGROUND: Outcome of Extracorporeal Shockwave Lithotripsy (SWL) is determined by physical factors that affect stone fragmentation and clearance. PURPOSE: To evaluate the predictive value of the Lithotripsy Table Height (LTH) in SWL outcome. Lithotripsy Table Height (LTH) is a variable that represents skin to therapy head distance, and it is proportional to the energy that reaches the stone. MATERIALS AND METHODS: A prospective study enrolled patients undergoing SWL for radiopaque urinary stones. All procedures were performed using a Modulith SLX (Karl Storz, Germany) Lithotripter. Patient weight, height and age; stone location and size; number of shock waves delivered, and LTH were recorded. One month post-procedure a KUB was obtained. Logistic regression analysis was used to evaluate the effects of these variables on stone-free outcome. A ROC curve was plotted. RESULTS: Fifty-six patients were enrolled. After one month follow-up, overall success rate (Stone Free) was 83.9% (n = 47). LTH was the only independent predictor of outcome in both univariate and multivariate analysis (p = 0.029). Stone size (p = 0.45) and BMI (p = 0.32) were not significant. In the ROC curve, LTH showed an Area under the Curve = 0.791. Patients with LTH < 218 (n = 8) had relative risk of residual stones = 7.5, odds Ratio: 6.6 (Stone free rate 37.5% vs. 91.5%). CONCLUSION: LTH appears to be an independent predictor of SWL outcome. High success rates can be expected if LTH > 218. Patients with lower LTH had a less effective therapy, therefore, worse stone fragmentation and clearance. These findings may help improve patient selection for SWL therapy. |
| first_indexed | 2024-12-10T11:36:07Z |
| format | Article |
| id | doaj.art-fe445e9ddd4a4ff88161b2e3f95a23d9 |
| institution | Directory Open Access Journal |
| issn | 1677-5538 1677-6119 |
| language | English |
| last_indexed | 2024-12-10T11:36:07Z |
| publishDate | 2011-06-01 |
| publisher | Sociedade Brasileira de Urologia |
| record_format | Article |
| series | International Brazilian Journal of Urology |
| spelling | doaj.art-fe445e9ddd4a4ff88161b2e3f95a23d92022-12-22T01:50:26ZengSociedade Brasileira de UrologiaInternational Brazilian Journal of Urology1677-55381677-61192011-06-0137335536110.1590/S1677-55382011000300009The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsyEnrique OssandonPedro RecabalCristian AcevedoJose Miguel FloresFernando MarchantBACKGROUND: Outcome of Extracorporeal Shockwave Lithotripsy (SWL) is determined by physical factors that affect stone fragmentation and clearance. PURPOSE: To evaluate the predictive value of the Lithotripsy Table Height (LTH) in SWL outcome. Lithotripsy Table Height (LTH) is a variable that represents skin to therapy head distance, and it is proportional to the energy that reaches the stone. MATERIALS AND METHODS: A prospective study enrolled patients undergoing SWL for radiopaque urinary stones. All procedures were performed using a Modulith SLX (Karl Storz, Germany) Lithotripter. Patient weight, height and age; stone location and size; number of shock waves delivered, and LTH were recorded. One month post-procedure a KUB was obtained. Logistic regression analysis was used to evaluate the effects of these variables on stone-free outcome. A ROC curve was plotted. RESULTS: Fifty-six patients were enrolled. After one month follow-up, overall success rate (Stone Free) was 83.9% (n = 47). LTH was the only independent predictor of outcome in both univariate and multivariate analysis (p = 0.029). Stone size (p = 0.45) and BMI (p = 0.32) were not significant. In the ROC curve, LTH showed an Area under the Curve = 0.791. Patients with LTH < 218 (n = 8) had relative risk of residual stones = 7.5, odds Ratio: 6.6 (Stone free rate 37.5% vs. 91.5%). CONCLUSION: LTH appears to be an independent predictor of SWL outcome. High success rates can be expected if LTH > 218. Patients with lower LTH had a less effective therapy, therefore, worse stone fragmentation and clearance. These findings may help improve patient selection for SWL therapy.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-55382011000300009extracorporeal shockwave lithotripsyhigh-energy shock wavestreatment outcomecalculi |
| spellingShingle | Enrique Ossandon Pedro Recabal Cristian Acevedo Jose Miguel Flores Fernando Marchant The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsy International Brazilian Journal of Urology extracorporeal shockwave lithotripsy high-energy shock waves treatment outcome calculi |
| title | The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsy |
| title_full | The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsy |
| title_fullStr | The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsy |
| title_full_unstemmed | The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsy |
| title_short | The lithotripsy table height: a novel predictor of outcome in shockwave lithotripsy |
| title_sort | lithotripsy table height a novel predictor of outcome in shockwave lithotripsy |
| topic | extracorporeal shockwave lithotripsy high-energy shock waves treatment outcome calculi |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-55382011000300009 |
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