Stone Destruction Research Articles

Extracorporeal Shock Wave Lithotripsy for Ureteral Calculi in Patients with Spinal Cord Injuries

Six patients with spinal cord injuries, including three paraplegics and two quadriplegics, underwent extracorporeal shock wave lithotripsy (ESWL) successfully for removal of ureteral calculi. The five proximal-ureteral calculi measured 20 to 35 mm; the single distal ureteral calculus measured 10 to 15 mm. General anesthesia was used in four patients, spinal anesthesia in one, and no anesthesia in one. All had pre-ESWL obstruction necessitating placement of a percutaneous nephrostomy tube, which was used during the procedure to instill constrast medium to monitor stone destruction. All patients had stone-free ureters on antegrade nephrostograms 7 days after ESWL. There were no significant complications, although one patient had fever and leukocytosis that resolved with intravenous antibiotics. ESWL appears to be highly successful in the removal of ureteral calculi in patients with spinal cord injuries.

Laser lithotripsy of gallstone by means of a pulsed neodymium-YAG laser--in vitro and animal experiments.

Using a flashlamp pulsed Nd: YAG laser it is possible to destroy gallstones within a few seconds (median: 4 sec for stones less than 1.5 cc; 9.5 sec greater than 1.5 cc). In in vitro and animal studies it was shown that the median energy needed for stone destruction varies between 32 Joule for stones less than 1.5 cc and 80 Joules for stones greater than 1.5 cc. A 0.2 mm thick, flexible glass fibre makes possible retrograde laser lithotripsy by conventional endoscopes. Using a suitable technique the danger of thermal damage to tissue is small.

Lasers in urology.

Our 9-year clinical experience with the Nd:YAG laser indicates that the conventional methods of tumor treatment in urology should be considered in urothelial tumors. In benign tumors of the genitalia and in penile cancer, the laser application is superior to all other conventional methods of treatment. Stone destruction by laser-induced shock waves could become very interesting, not only in urinary tract stones but also in gall bladder stones.

Experimental investigation of neodymium-YAG laser induced shock waves for lithotripsy.

Experiments on the endoscopic destruction of kidney stones by neodymium-YAG laser, either thermically or mechanically, are being carried out with various results. The thermal destruction is clinically not feasible, and the risk of damaging neighboring tissue is inevitable. The direct generation of shock waves with pulsed Q-switch systems seems to represent the only feasible endoscopic method subject to further development of suitable devices for clinical tests.

Percutaneous microexplosion nephrolithotripsy

We developed the technique of microexplosion for the destruction of bladder stones and have used it since 1981 with good results. The procedure is safe and simple. A renal pelvic stone in a seventy-one-year-old woman was successfully destroyed by microexplosion using a percutaneous approach. We believe this is the first clinical report on the use of microexplosion for upper urinary tract calculi.

Percutaneous nephrolithotomy: Advances in equipment and endoscopic techniques

Over the last two years there has been a 30-per cent increase in our success rate for percutaneous nephrolithotomy. A significant reason for this has been advances in endoscopic equipment. We describe our new lightweight nephroscopes and how they may be used in combination with the Amplatz sheath. Seventeen patients who were successfully treated by electrohydraulic disintegration are reported. We believe this method to be preferable to ultrasonic stone destruction in most cases. The first report of the clinical use of bipolar diathermy for intrarenal endoscopy is described.

First Clinical Experience with Extracorporeally Induced Destruction of Kidney Stones by Shock Waves

We performed extracorporeally induced destruction of kidney stones on 72 patients. No complications have resulted from the tissue exposure to high energy shock waves. Clearance studies before and after the shock wave treatment indicate no changes in renal function. The method was used successfully in all patients with stones in the renal pelvis. In none of these patients was an open operation required. Two patients with ureteral stones also were treated with shock waves but had to be operated upon because of insufficient destruction of the stone.

レーザー光線の泌尿器科領域への応用

1) We have already reported on drilling experiments of extracted urinary calculi by the use of laser beam.2) As the second step, experiments using a CO2 gas laser guided through a manipulator which consists of three arms and mirrors, and also using a Nd:YAG laser guided through an optical fiber, was performed.3) Some stones were not merely perforated but also disintegrated in a wet condition.4) Although a CO2 gas laser was more effective than a Nd:YAG laser in the destruction of stones, an optical fiber combined with Nd:YAG laser was easier to handle than a manipulator combinded with a CO2 gas laser.

Some properties of crushed stone for road surfaces

On wet roads a sufficiently rough surface texture on the macroscale is necessary to ensure rapid removal of water from the contact zone between the tire and road surface, especially at high speeds. For this surface texture on the macroscale, beside the particle size of the aggregate also the resistance to crushing and abrasion is rather important. The macroroughness is likely to decrease rapidly in case of insufficient resistance to crushing which will cause destruction of stones at the surface. It decreases too, if the resistance to abrasion of stones, which protrude from the road surface, is poor. The texture depth, which is a measure of the roughness on the macroscale, can easily be determined. A satisfactory surface texture on the microscale is required as well, because this texture is at least largely determinant of the level of skid resistance. It is not yet possible to express the surface texture on the microscale in a number. The resistance to polishing of aggregates can, however, be expressed as the polished stone value which is determined in the laboratory using an apparatus for accelerated polishing. The correlation between the polished-stone value and the skid resistance, i.e. the similarity with practice, appears to be good in cases in which the surface consists of a continuous mosaic of coarse aggregate such as in surface dressings. Finally also the shape of the stone particles may be important for the skid resistance (unfractured faces in crushed gravel) and for the resistance to crushing (thin pieces).

The destruction of grave stones

The destruction of grave stones Get access J. W. F. J. W. F. Search for other works by this author on: Oxford Academic Google Scholar Notes and Queries, Volume 174, Issue 8, 19 February 1938, Page 137, https://doi.org/10.1093/nq/174.8.137b Published: 19 February 1938