[Extracorporeal shockwave lithotripsy in cholecystolithiasis using a new type of minilithotripter]

Extracorporeal shock wave lithotripsy (ESWL) of gallstones has until now required fixed, nearly room-sized and expensive equipment. It has become even less cost-effective with an increase in the number of laparoscopic cholecystectomies. The authors have technically modified a mini-lithotripter, used for dissolving salivary stones, for application against gallstones (by changing the energy spectrum and depth of focus).

125 consecutive patients with solitary gallstone underwent lithotripsy according to a standard protocol (including oral litholysis), 64 of them (average age 42.5 +/- 9.3 years; 44 women, 20 men) by conventional ESWL (with the Modulith), 62 (average age 41.6 +/- 10.1 years; 43 women, 13 men) with a modified mini-lithotripter (Minilith). Clinical and sonographic follow-up took place at 1, 3, 6 and 12 months. Quality of life was documented according to a point score (GIQL), developed specially for patients with gastrointestinal conditions.

The mini-lithotripter applied significantly lower voltage and more shock-wave impulses per treatment than the conventional ESWL (p < 0.01), while patient tolerance, measured with a visual analogue scale, was the same. Application of the mini-lithotripter was easier and quicker than with conventional ESWL, namely 31 +/- 8 min vs 41 +/- 12 min (p < 0.01). Frequency of adequate stone fragmentation per patient was the same for both methods, 2.2 +/- 0.5 applications with the mini-lithotripter vs 1.6 +/- 0.3 with conventional ESWL (p < 0.01). There was no significant difference between the methods with regard to improved quality of life (increase of GIQL scale of 16% with the conventional ESWL, 14% with the mini-lithotripter) or freedom from stone at 1 year after lithotripsy (conventional ESWL: 80%, mini-lithotripter: 82%). Colics recurred in 15 of 64 patients receiving conventional ESWL, and in 13 of 61 in the mini-lithotripter group (difference not significant). There were no other complications.

The cheaper mini-lithotripter, costing only a third of the conventional ESWL, is equally effective in the dissolution of gallstones.