Experience of Extracorporeal Shock Wave Lithotripsy with Northgate SD-3 in 2500 Patients of Urinary Calculi

Lee, Jong Tae; Park, Do Young; Chang, Dae Soo

Abstract

Extracorporeal shock wave lithotripsy (ESWL) has been established as the first line procedure of urinary stone treatment. To evaluate clinical efficacy and to identify the criteria of proper patient selection tempered by understanding of the limitations of the ESWL therapy available. We reviewed 2500 patients with urinary stone treated by ESWL using the Northgate SD-3 lithotriptor between June, 1989 and May, 1995. The results were obtained as follows: 1. The total average success rate of treatment was 92.6%. 2. The success rate according to stone locations were 88% in kidney (1074/1214 cases), 93.5% in ureter(1275/1323 cases) and 92.7% in bladder (38/41 cases). 3. The success rate according to stone size measured on the KUB film were 98.0% below 10mm, 91.0% in 11 - 20mm, 80.0% in 21 - 30mm and 68.7% over 31mm. 4. The average numbers of treatment were 2.3 sessions and the mean number of shock per treatment were 1940 +- 230. 5. Of the 2578 cases, 2178(84.5%) were treated by ESWL monotherapy. For auxiliary procedure, Double-J stents were placed in 64 cases and nephrostomy in 49 cases. Stone manipulation including push back, Dormia basket, Ureteroscopy were performed in 161 cases. We conclude that as a highly effective and minimally invasive treatment modality, ESWL has become to be the therapy of choice in 85.5% of urinary stones. When ESWL therapy is less effective for stone size larger than 3 cm(68.7%), staghorn calculi (65.5%) and presence of anatomical barriers, the additional endourologic procedures need to be indicated.