Impact of Renal Anatomy on Shock Wave Lithotripsy Outcomes for Lower Pole Kidney Stones

NCT ID: NCT01589484

Last Updated: 2015-01-07

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 104 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-04-30
• Study Completion Date: 2014-12-31

Brief Summary

Kidney stone disease affects almost 10% of overall population, often requiring a surgical intervention. Currently, shock wave lithotripsy is considered a first-line treatment option for patients suffering from symptomatic kidney stones smaller than 2.0 cm, providing reasonable stone-free rate. Actually, the outcomes from SWL vary largely due to several factors including stone burden, stone density, stone-skin distance (SSD), and patient's body habitus. Furthermore, the imaging exam modality (i.e. ultrasound versus computed tomography scan) performed to assess the presence of residual fragments also impacts on SWL outcome analysis.

We aim to perform a well-controlled prospective evaluation of all variables that may impact on fragmentation and clearance of lower pole calculi after SWL. These variables are assessed exclusively by a noncontrast computed tomography scan (NCCT), eliminating the necessity of an intravenous urography to study renal collecting system anatomy; an imaging exam that is not routinely performed anymore for kidney stone patients.

Detailed Description

Variables in study:

• Age, gender, body mass index (BMI), and waist abdominal circumference
• Noncontrast computed tomography scan (NCCT): stone density (average of 3 measurements), stone size, stone area, skin to stone distance (average of 3 measurements: zero, 45o and 90o), and collecting system anatomy: infundibular length, width, and height, and infundibulopelvic angle

Study design:

All patients will be submitted to a noncontrast computed tomography scan before to SWL. A radiologist with expertise in urolithiasis will evaluate all exams.

Patients will be submitted to SWL under the following conditions: outpatient, general anesthesia, 3000 impulses, rate of 90/min, discharged from hospital in the same day with alpha-blocker (doxazosin) during 30 days.

Patients will be followed up as follow:

• One week after SWL: medical visit To evaluate complications such as pain, dysuria, hematuria, steinstrasse, visit to the emergency department.
• 12 weeks after SWL: new NCCT scan To evaluate kidney stones fragmentation and clearance.

Univariate (Student's T test) and multivariate analysis (multiple logistic regression) will be done to assess the impact of patient's corporal habitus (BMI and abdominal waist circumference), stone characteristics (size, area, density and SSD), and renal collecting system anatomy (infundibular length, width and height, and infundibulopelvic angle) on SWL outcomes (fragmentation and stone-free rates).

Conditions

Urolithiasis; Urinary Lithiasis; Kidney Calculi

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Shockwave lithotripsy (SWL)

All patients will be submitted to a noncontrast computed tomography before to shockwave lithotripsy (SWL). Patients will be submitted to SWL under the following conditions: outpatient, general anesthesia, 3000 impulses, rate of 90/min, discharged from hospital in the same day with alpha-blocker (doxazosin) during 30 days.

Group Type: EXPERIMENTAL

SWL - Compact Delta Dornier Med Tech

Intervention Type: DEVICE

All patients will be submitted to a noncontrast computed tomography before to SWL. Patients will be submitted to SWL under the following conditions: outpatient, general anesthesia, 3000 impulses, rate of 90/min, discharged from hospital in the same day with alpha-blocker (doxazosin) during 30 days.

Interventions

SWL - Compact Delta Dornier Med Tech

All patients will be submitted to a noncontrast computed tomography before to SWL. Patients will be submitted to SWL under the following conditions: outpatient, general anesthesia, 3000 impulses, rate of 90/min, discharged from hospital in the same day with alpha-blocker (doxazosin) during 30 days.

Intervention Type: DEVICE

Other Intervention Names

Extracorporeal shockwave lithotripsy; Compact Delta Dornier Med Tech; Nephrolithotripsy

Eligibility Criteria

Inclusion Criteria

> 17 year-old. Symptomatic single stone of 5 to 20mm located in the lower pole of the kidney. Informed consent signed.

Exclusion Criteria

Patients with congenital kidney abnormalities (i.e. horseshoes kidney, pelvic kidney, ectopic kidney), patients with ureteral stent (i.e. Double J stent) in the ipsilateral kidney of the stone in study, patients with chronic kidney disease (glomerular filtration rate <60 mL/minute/1.73m2 measured by the equation "Modification of Diet in Renal Disease"), and patients with absolute contraindication to SWL (i.e. coagulopathy, pregnancy, urinary tract infection, or abdominal aneurysm >4.0cm).

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Sao Paulo

OTHER

Sponsor Role: lead

Responsible Party

Fabio Cesar Miranda Torricelli

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Fabio CM Torricelli, MD

Role: PRINCIPAL_INVESTIGATOR

University of Sao Paulo

Locations

University of Sao Paulo

São Paulo, São Paulo, Brazil

Countries

Brazil

Other Identifiers

00795812.8.0000.0068

Identifier Type: -

Identifier Source: org_study_id