A study of 401 cases presents the outcomes with a Dornier Compact Delta lithotripter in treating ureteral stones from a single center in Japan. Treatment with ESWL from a third generation lithotripter is associated with a high stone free rate and small number of treatment sessions. This non-invasive, ESWL procedure can be the first line treatment of all ureteric stones.
Almost all patients (98%) received outpatient treatment. Appropriate analgesia was used and patients were treated in the supine position. The treatment head was positioned under the table for proximal ureteric stones and over the table for mid-distal ureteric stones. Although the intended number of total shocks for each patient was 3000 per session, it was stopped earlier if fluoroscopy showed sufficient fragmentation. The shocks were administered at the rate of 60 shocks per minute. The treatment was started with the lowest intensity and gradually increased to the recommended level (16 mJ/shot). About 200 shots were administered at each level. After treatment, patients were categorized as stone free, success (residual fragments £4 mm) or failure (residual fragments >4 mm).
- A total of 331 patients received treatment for only one session. Only 1 patient did not have satisfactory results.
- Among stone free patients, patients with smaller stones were more likely to be stone free after a single session as compared to larger stones. (90.1% vs. 77.5%; p=0.0008). There was no difference on the basis of stone location.
- Overall, 22 patients did not achieve stone free status even after multiple sessions. Of these, 18 patients were deemed success as the residual fragments were £4mm.
- Only one patient developed subcapsular renal hematoma (major complication) associated with severe flank pain which resolved with conservative treatment.
In patients with ureteric stones, including mid-distal stones, treatment with a third generation lithotripter is associated with a high stone free rate and small number of treatment sessions. This non-invasive procedure can be the first line treatment of all ureteric stones.