[Ultrasound-guided renal cyst puncture and 95% ethanol injection. Part 1: Estimation of ethanol levels in the blood and urine following 95% ethanol injection].

Seventeen solitary renal cysts were punctured with the ultrasound-guided procedure and 26-91% of the cyst volume was replaced with 95% ethanol used as a sclerosing agent of the cyst wall. Ethanol was injected through a 7 F pigtail ureteral catheter, allowed to remain in place for 20 minutes and removed through the catheter. Recovery rate of ethanol was 82.4%. The maximum blood level of ethanol was obtained 30 to 60 minutes after injection, while the maximum urinary excretion rate was observed after 60 to 120 minutes. The maximum blood levels of ethanol ranged from 0.015 to 0.339 mg/ml. There was a positive correlation between injected volume of ethanol and the maximum blood level (r = 0.66) or the total amount of urinary excretion during 12 hours (r = 0.72). Residual ethanol concentrations in the body were calculated from injected volume and recovery rate of ethanol. Only 2.3% of the residual ethanol in the body was excreted in the urine during the first 12 hours after injection. However, urine/blood ratio of ethanol 1 hour after injection was tremendously high with a wide variation between 1.6 and 230.5. Therefore, a large part of the ethanol absorbed from the cyst wall seems to be excreted directly from the kidney, not entering general circulation. From the estimation of the blood and urine levels of ethanol, it is concluded that 95% ethanol can be applied to the renal cyst wall as a sclerosing agent through the percutaneous ultrasound-guided procedure in the case of good recovery of ethanol.