John H.O. Mertz

Comparison of Results and Morbidity of Percutaneous Nephrostolithotomy and Extracorporeal Shock Wave Lithotripsy

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.

Extracorporeal Shock Wave Lithotripsy Experience in Children

Extracorporeal shock wave lithotripsy treatment for calculi of the upper urinary tract was performed in 15 children between 3 and 17 years old. Success was achieved in 93 per cent of the cases (72 per cent were free of stone and 21 per cent had insignificant fragments). No major complications were encountered in the series.

Extracorporeal Shock Wave Lithotripsy

Extracorporeal shock-wave lithotripsy has been proposed a s a modality to facilitate the removal of bone cement during revision arthroplasty; however, concomitant cortical microfractures have been reported. The current study examines the effect on whole bone strength of extracorporeal shock-wave lithotripsy directed a t the cementbone complex. Canine femora were subjected to manual cement extraction or lithotripsy followed by manual cement extraction. Contralateral femora served as controls. Torsional fractures were created, and maximum torque, maximum angular displacement, and energy capacity to failure were determined. Although cement extraction alone reduced mean torque by 6.6% and failed to reduce mean torque angle or mean energy capacity, the combination of lithotripsy and cement extraction reduced mean torque by 7.3470, mean torque angle by 14.3%, and mean energy capacity by 18.3%. No statistical significance was demonstrated between the two groups in torque, angle, or energy capacity. At magnitudes and numbers of shock waves previously shown to significant11 reduce cement-bone interface mechanical strength, lithotripsy exposure had a minimal and insignificant effect on whole bone strength.

Extracorporeal Shock-Wave Lithotripsy

Analysis of our data clearly demonstrates that morbidity, secondary treatment, post-treatment manipulations, and failure of treatment increase as the stone size increases because of the increased stone fragment burden. Patients whose stone burden was less than 2 cm clearly had less morbidity. Composition of the stone may also alter the success of treatment (with cystine, calcium oxalate monohydrate, and brushite stones being resistant to treatment). However, post-treatment morbidity and complications were observed in all categories. Perirenal hematomas are unpredictable by current preoperative testing. Obstruction with pain can occur any time after treatment but usually occurs within the first 48 hours in the majority of patients. Only 1 per cent of our patients required hospitalization in another institution after discharge. Ambulatory ESWL requires that staff at the facility or a urologist be able to observe and appropriately follow the patient for 24 to 48 hours after treatment.

DIVERTICULUM OF THE FEMALE URETHRA, WITH SPECIAL REFERENCE TO DIVERTICULAR CARCINOMA

Diverticulum is being recognized more frequently as the urologist searches for the lesion. Carcinoma as a complication is quite rare.