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Shockwave Lithotripsy (shockwave + lithotripsy)
Kinds of Shockwave Lithotripsy Selected AbstractsLower pole ratio: A new and accurate predictor of lower pole stone clearance after shockwave lithotripsy?INTERNATIONAL JOURNAL OF UROLOGY, Issue 9 2004YAN KIT FONG Abstract Background: Lower pole spatial anatomy is an important determinant of success after extracorporeal shockwave lithotripsy. In the present study, we determine whether there is a significant relationship between lower pole ratio (infundibular length : infundibular width) on preoperative intravenous urograms and stone fragment clearances after shockwave lithotripsy. Methods: A total of 42 patients with isolated lower pole stones were retrospectively reviewed. Anatomical factors, such as infundibular length, width and infundibulopelvic angle were measured and the lower pole ratio was calculated on pretreatment intravenous urogram. Stone fragment clearance was assessed at three months with a plain abdominal X-ray. Results: The overall three-month stone-free rate was 62%. Mean stone size ± SD was 10 ± 4.8 mm, mean infundibular length was 21.7 ± 6.9 mm, mean infundibular width was 6.1 ± 2.3 mm, mean infundibulopelvic angle was 62.1 ± 30.1 degrees and mean lower pole ratio was 4.3 ± 2.8. Stone-free status after shockwave lithotripsy was significantly related to infundibular length and width as well as to lower pole ratio, but not to infundibulo-pelvic angle. Infundibular length less than 30 mm, width greater than 5 mm and lower pole ratio less than 3.5 were noted to have an improved three-month stone-free rate (P = 0.049, 0.01 and <0.01, respectively). Conclusion: Caliceal anatomy is an important consideration for lower pole stone clearance after shockwave lithotripsy. The present study suggests that a lower pole ratio of less than 3.5, which considers both infundibular length and width, is a promising predictor for stone-free status. [source] Significance and diagnostic accuracy of renal calculi found by ultrasonography in patients with asymptomatic microscopic hematuriaINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2002Ken Marumo Abstract Background : The purpose of the present study was to evaluate the clinical significance and the accuracy of the diagnosis of renal calculi incidentally found by ultrasonography (US). Methods : A total of 906 subjects (639 men and 267 women) aged 18,78 years were referred for asymptomatic microscopic hematuria. Of these, 743 patients who underwent US were studied. Results : Hyperechogenic spots in the central echo complex suggesting renal calculi were noted in 195 patients (21.5%). The occurrence of hyperechogenic spots was higher in patients with 20 or more urinary red blood cells per high-power field (,2 = 4.896, P = 0.0269) and in men than in women (,2 = 7.101, P = 0.0077), but it was lowest in patients who were 29 years old or younger. Of these 195 patients, who were followed up for 1,161 months (average: 33.5 months), 24 patients (12.3%) needed urological management. Extracorporeal shockwave lithotripsy was carried out in eight patients, transureteral lithotripsy was carried out in three patients, spontaneous passage occurred in 11 patients and medication for hyperuricemia was initiated in two patients (1%). Among the patients in whom hyperechogenic spots were found in the kidney by US but calculi were not visible on abdominal plain radiographs, 39 patients underwent computed tomography. Of them, 31 patients were confirmed to have renal calculi. Conclusion : The obtained results suggest that US is an effective and reliable means of detecting renal calculi in patients with asymptomatic microscopic hematuria, and in facilitating prompt urological intervention or predicting the natural course of renal calculi. [source] Examination of whewellite kidney stones by scanning electron microscopy and powder neutron diffraction techniquesJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 1 2009Michel Daudon Kidney stones made of whewellite, i.e. calcium oxalate monohydrate, exhibit various morphological aspects. The crystalline structure of whewellite at the atomic scale was revisited through a single-crystal neutron study at room temperature using a four-circle automated diffractometer. The possible relationships between the various morphological types of whewellite stones and their structural characteristics were examined at the mesoscopic scale by the use of scanning electron microscopy and at the nanometric scale by powder neutron diffraction. All types of whewellite stones displayed a similar structure at the nanometric scale. However, significant differences were found at the mesoscopic scale. In particular, the crystallites in kidney stones resulting from a genetic hyperoxaluria exhibited a peculiar structure. There was a close relationship between stone morphology and crystallite organization at the mesoscopic level and the effectiveness of extracorporeal shockwave lithotripsy. [source] Ureteric stents compromise stone clearance after shockwave lithotripsy for ureteric stones: results of a matched-pair analysisBJU INTERNATIONAL, Issue 1 2009Athanasios N. Argyropoulos OBJECTIVE To identify the effect of the presence of a ureteric stent on the outcome of extracorporeal shockwave lithotripsy (ESWL), by comparing patients with ureteric stones with matched-pair analysis. PATIENTS AND METHODS Patients undergoing ESWL with the Sonolith Vision lithotripter (Technomed Medical Systems, Vaulx-en-Velin, France) were identified from our prospectively maintained database. Only adult patients with a solitary, radio-opaque, previously untreated ureteric stone were considered for further analysis. A follow-up of ,3 months with a plain abdominal film was used to identify residual fragments. Patients were exactly matched for gender, side, location in the ureter and size (in two dimensions, within ±2 mm). If both diameters could not be matched exactly, the size was extended to ±1 mm and then to ±2 mm of both diameters. An effort was finally made to match patients by age. The treatment outcome in terms of stone-free rates was assessed and compared using McNemar's test. RESULTS In all, 45 patients with a ureteric stent in place during ESWL were identified. The only patient who could not be adequately matched was a 40-year-old man with an 8 × 3 mm stone in the upper ureter. The best/closest match for age was selected. Most stones were in the upper ureter (77%); the mean stone size was 8.5 and 8.6 mm, respectively, with no statistical differences between the groups for age and size of stones (P = 0.41 and 0.86, Student's t -test). In 12 pairs, only patients with no stent were stone-free, compared to two pairs where the patient with a stent was stone-free. Using McNemar's test, the odds ratio was 6.0 (95% confidence interval 1.3,55.2) and the difference between the groups was statistically significant (P = 0.016). CONCLUSION These results show that the presence of a stent is associated with a worse outcome after ESWL for ureteric stones. Ureteric stents should still be used in cases of obstruction, when there is a risk of sepsis, and in patients with intolerable pain or deteriorating renal function. However, their use in patients offered ESWL for ureteric stones should be considered with caution. [source] Percutaneous nephrolithotomy with ultrasonography-guided renal access: experience from over 300 casesBJU INTERNATIONAL, Issue 6 2005Mahmoud Osman OBJECTIVE To report our experience with over 300 patients treated with percutaneous nephrolithotomy (PNL), for although PNL was established as a treatment in the 1970s, its use diminished with the introduction of extracorporeal shockwave lithotripsy (ESWL); clinical experience with ESWL showed its limitations, and the role of PNL for treating urolithiasis was redefined, which with improvements in instruments and lithotripsy technology has expanded the capability of percutaneous stone disintegration. PATIENTS AND METHODS The study included 315 patients (156 males, 159 females, aged 13,85 years) treated with PNL in our department between 1987 and 2002. The mean (range) stone diameter was 27 (7,52) mm. The kidney was punctured under ultrasonography guidance via a lower-pole calyx whenever possible. The working channel was dilated using an Alken dilator under X-ray control. If necessary, a flexible renoscope was used. Ultrasonic, pneumatic and laser probes were used for lithotripsy. RESULTS Four weeks after treatment the total stone-free rate was 96.5%; 45.7% of all patients were primarily stone-free, 21.3% had clinically insignificant residual stones that passed spontaneously within 4 weeks after PNL, and 33% of the patients needed auxiliary measures (a second PNL, ESWL, ureterorenoscopy). Overall, the early complication rate was 50.8%, the most common complications being transient fever (27.6%), clinically insignificant bleeding (7.6%) or both (3.2%); 3.5% of the patients developed urinary tract infections (with no signs of urosepsis), 3.2% had renal colic and 2.9% upper urinary tract obstruction. One patient (0.3%) developed acute pancreatitis after PNL; one died from urosepsis and one needed selective angiographic embolization of the punctured kidney due to bleeding. No patient required transfusions and there were no injuries to neighbouring organs. CONCLUSIONS These results show that PNL causes no significant blood loss or major complications in almost all patients. Two aspects may especially reduce the potential complications: ultrasonography-guided renal puncture and using PNL in an experienced centre. PNL is a highly efficient procedure that provides fast and safe stone removal. [source] The efficacy of a range of contact media as coupling agents in extracorporeal shockwave lithotripsyBJU INTERNATIONAL, Issue 4 2001J.J. Cartledge Objective To determine if the nature of the coupling agent normally used between the lithotripter and the patient affects the stone fragmentation rate during extracorporeal shock wave lithotripsy. Materials and methods A jig designed to hold ,phantom' 10-mm stones at the focal point was fixed against the shock wave delivery point of an electromagnetic lithotripter (Dornier Compact, Germany). A layer of either petroleum jelly (VaselineÔ, Cheeseborough-Ponds Ltd, London, UK) ultrasonography jelly, a eutectic mixture of local anaesthetic (EMLA) cream, Instillagel (Farco-Pharma, Cologne, Germany) or a commercial water-soluble lubricating jelly was placed between the jig and shockwave head, and the number of shock waves required to fragment the stones was recorded. Results Significantly more shock waves were required to fragment stones when petroleum jelly was used as the coupling agent than with all the other agents under test, whereas significantly fewer shock waves were required when using Instillagel or lubricating jelly than for all other agents. Conclusion The coupling agent used in water-free lithotripsy can affect the stone fragmentation rate and should not be considered inert. Ultrasonography jelly is probably the optimum agent available for use as a lithotripsy coupling agent. [source] | ||||||||||