Siberian State Medical University (Tomsk, Russia)
Endoscopic treatment of urolithiasis using different lithotripters is widespread and continues to evolve. From February to May 2006, the hospital urology department of the Siberian State Medical University conducted medical tests of the Urolit contact nanopulse lithotripter produced by MedLine, Tomsk, Russian Federation.
The Urolit device consists of the following parts: a pulse generator of nanosecond duration combined with an electronic control unit in one box; working flexible probes of various diameters; a control pedal. A stone is fragmented by a nanopulse generated inside it due to the direct contact of the flexible probe with the stone.
Purpose: Determine the Urolit lithotripter's effectiveness and safety for endoscopic contact lithotripsy of ureteral calculi and bladder stones.
Materials and Methods: Contact lithotripsy was performed in 24 patients (15 women and 9 men). The mean age was 35.9 ± 18.0 years (age range - 25 to 72 years). Contact lithotripsy was carried out in the upper third part of the ureter in 3 (12.5%) patients, in the middle third in 2 (8.3%) patients, and in the lower third in 15 patients (62.5%). Contact lithotripsy was performed in the urinary bladder in 4 (16.7%) patients.
Results: For ureteral stones, lithotripsy was carried out using the following settings: pulse energy 0.3-0.4 J, pulse repetition frequency 5 Hz, and the number of pulses ranging from 1 to 3. The choice of these parameters was stipulated by the small size of concrements - from 0.5 to 0.8 cm. Depending on the location of the stone and its size, the duration of contact lithotripsy ranged from 2 to 8 minutes.
For the patients with bladder stones, lithotripsy was carried out using the following settings: pulse energy 0.6 J, pulse repetition frequency 5 Hz, and the number of pulses ranging from 2 to 4. This was due to the large size (from 1.5 to 3.5 cm) and hardness of the stones. The procedure lasted from 5 to 15 minutes.
Lithotripsy was successful in all patients, no complications took place, and all patients were discharged in satisfactory condition.
Significant advantages of the device are its compact size, relatively light weight, comfort and ease of use.
Conclusions. Thus, contact nanopulse lithotripsy using the Urolit lithotripter is a highly effective, safe and state-of-the-art method for treating urolithiasis.