Ultrasound monitoring of kidney stone extracorporeal shockwave lithotripsy with an external transducer: does fatty tissue cause image distortions that affect stone comminution?

Introduction: Ultrasound imaging, using either an inline or an external transducer, is a standard method for extracorporeal shockwave lithotripsy (SWL) monitoring. This study investigates whether image distortions caused by the low sound speed of fatty tissue could lead to incorrect stone positioning such that disintegration is affected.

Materials And Methods: To define the accuracy needed for SWL monitoring, the dependency of fragmentation efficiency on the distance between stone center and SWL focus was examined by in vitro model stone tests.

Minimal invasive therapy of ureteral calculi using modern techniques.

In a one year period from July 1985 to July 1986, 224 upper and 62 distal ureteric calculi were treated. In situ ESWL represents the therapy of first choice for upper and distal ureteric calculi with a success rate of 81% and 76%, respectively. Retrograde mobilization of the calculus was used only in cases where in situ ESWL was impossible because of localization difficulties (obesity, stone close to the spine, skeleton deformation).

Minimally invasive treatment of ureteric calculi using modern techniques.

Between July 1985 and July 1986, 226 upper and 62 distal ureteric calculi were treated. In situ extracorporeal shockwave lithotripsy (ESWL) is the treatment of choice for upper and distal ureteric calculi, with success rates of 81 and 76% respectively. Retrograde manipulation of the calculus was undertaken only when in situ ESWL was impossible because of difficulty in localisation.

ESWL for ureteral calculi. Using the Dornier HM 3, HM 3+ and Wolf Piezolith 2,200.

In a one year period from July 1985 to July 1986 226 upper and 62 distal ureteric calculi were treated. In situ ESWL represents the therapy of first choice for upper and distal ureteric calculi with a success rate of 81% and 76% respectively. Retrograde mobilization of the calculus was used only in cases where in situ ESWL was impossible because of localization difficulties (obesity, stone close to the spine, skeleton deformation).

Wolf Piezolith 2200 versus the modified Dornier HM3. Efficacy and range of indications.

From February to September 1987, a prospective study was performed at two clinics to compare the Piezolith and the Dornier HM3+ lithotripters. Based on the same clinical indications for extracorporeal shock wave lithotripsy, 334 patients were treated with the Dornier HM3+ and 378 patients with the Piezolith. Whereas stone size was similar in both groups, more ureteral calculi were treated with the Dornier HM3+ (31.

Multimodal treatment (extracorporeal shock wave lithotripsy and endourology) of complicated renal stone disease.

From October 1983, (installation of the extracorporeal shock wave lithotripsy unit) to August 1985, 207 patients presented at the Katharinenhospital Stuttgart with complicated renal stone disease (70 borderline stones, 77 partial and 60 complete staghorn calculi). 197 patients were treated with the new technology for urinary stone therapy, i.e.

Efficacy of in situ extracorporeal shock wave lithotripsy for upper ureteral calculi.

In contrast to the majority of renal calculi, in situ extracorporeal shock wave lithotripsy (ESWL) for upper ureteral stones is still controversial. Some centers recommend retrograde mobilization of the calculus into the renal pelvis prior to ESWL as a routine procedure (UC + ESWL). To evaluate the efficiency of in situ ESWL for upper ureteric stones, we initiated a prospective clinical trial.

[Stereoroentgenology in endourology].

Three-dimensional stereofluoroscopic pictures of the kidney and renal calyces were first used for percutaneous renal surgery with a laboratory prototype equipment. The grid-controlled X-ray tube provides sequential images, which are separated into pairs by digital image processing and storage and can be seen on a 3-D display unit. This method allows exact and rapid puncture of a suitable calyx for percutaneous nephrolithotomy, shortens the learning process for the endourologist, reduces the radiation exposure, and thus makes the method safer.

Antegrade ureteroscopy for stone removal.

Antegrade ureteroscopy, using the 11-French ureteroscope via a percutaneous transrenal access, provides safe and easy endoscopic exploration of the ureter above the level of the iliac vessels. The technique has proven to be reliable and effective for the removal of obstructing proximal ureteral calculi: all of the 22 patients who underwent antegrade ureteroscopy were stone-free after treatment. Since the introduction of this new technique in our department, no more open surgery has been required to manage ureteral calculi.