Testosterone (T) levels in the plasma of male laboratory rats and mice were measured by radioimmunoassay. There was a striking individual variation with values ranging from less than 1 ng/ml to over 30 ng/ml in mice of the same age and strain housed under identical conditions. Using chronic indwelling catheters inserted into a jugular vein, blood was collected from adult conscious male rats every 24 hr for 4 or 8 days and every 30 min for 2 l / 2 or 8 hr. Considerable differences in plasma T levels were observed between different animals, and 2-to S-fold fluctuations of T concentrations in the plasma were detected between samples collected from the same animal at different times. These large and irregular changes in plasma levels of T are unlike the fairly stable levels observed in the human but bear certain resemblance to the pulsatile release of T described in bulls and rams and perhaps also to the social dominance related differences in plasma T levels in Rhesus monkeys. {Endocrinology 92: 1223, 1973

A total of 982 patients underwent 1,416 treatments with extracorporeal shock wave lithotripsy for upper urinary tract calculi between February 23 and December 17, 1984. A single treatment was performed in 90 per cent of the patients. Morbidity was extremely low and hospital stay was short (3.0 days). Adjunctive procedures were required in 13 per cent of the patients. Of the kidneys 72 per cent were free of stones at the 3-month followup, while 23 per cent contained small (less than 5 mm.), asymptomatic fragments believed to be passable spontaneously. Only 1 per cent of the patients required surgical removal of the calculi. Morbidity was related directly to stone burden, while results were inversely related to stone burden. Extracorporeal shock wave lithotripsy is the preferred form of management for symptomatic upper ureteral and renal calculi less than 2 cm. in diameter.

Two new therapies, percutaneous nephrostolithotomy and extracorporeal shock wave lithotripsy, are revolutionizing the treatment of upper urinary tract calculi. We report the success and morbidity rates in 110 patients undergoing percutaneous nephrostolithotomy and 982 patients treated with extracorporeal shock wave lithotripsy. Staghorn calculi were excluded from this series. The over-all success rate (free of stones plus small asymptomatic residual fragments) was comparable with both modalities (percutaneous nephrostolithotomy 98 per cent and extracorporeal shock wave lithotripsy 95 per cent), although the presence of residual fragments was more common in kidneys treated with extracorporeal shock wave lithotripsy (24 versus 7 per cent). Patient morbidity as measured by temperature elevation, length of postoperative stay, pain and blood loss was significantly less (p less than 0.05) with extracorporeal shock wave lithotripsy than with percutaneous nephrostolithotomy. Re-treatment rates were similar with both procedures, and tended to increase in relation to increasing stone size and stone number. Post-treatment ancillary procedures (cystoscopy and stone manipulation, and percutaneous nephrostomy) were used more frequently with extracorporeal shock wave lithotripsy. Because of its efficacy and low morbidity, we conclude that extracorporeal shock wave lithotripsy is the treatment of choice for upper urinary tract calculi less than 2 cm. in diameter. However, percutaneous nephrostolithotomy will continue to have a primary role in the management of larger stones and cystine stones, and it will be used as a secondary procedure after unsuccessful extracorporeal shock wave lithotripsy treatments. In addition, because of the complimentary nature of these 2 new technologies certain complex stones, such as staghorn calculi, may be handled best by a combination of the 2 techniques.