[Percutaneous renal cyst puncture with CO2 instillation therapy].

Ultrasound-guided percutaneous puncture of renal cysts replaced by CO2 was performed on 9 renal cysts of 6 patients from May 1993 through September 1993. Puncture and aspiration of cysts was performed using a 5.5 Fr one-step fluid drain kit (pig tail stent) under ultrasonography inspection. Aspirated volume of cyst contents was 15-292ml (mean 115 ml), and the instilled CO2 volume was 15-150 ml (mean 73 ml). All patients were checked by CT scan. In one month, the reduction rate of cyst volume was 46-84% (mean 69%) and lumbago, their chief complaint, was improved in all patients. No complications were observed in patients treated by CO2 instillation. Although long-term followup is needed to draw a definite conclusion, this therapy may be useful for benign renal cystic lesions.