Intracorporeal lithotripsy of salivary stones: in-vitro comparison of different methods

Objective The Ho:YAG laser (laser lithotripsy LL) and a pneumatic device (PL) are currently approved for the intracorporeal lithotripsy of salivary stones. The latter one is no longer available and a demand for alternative options exists. Electrokinetic (EKL) and electrohydraulic lithotripsy (EHL) with the Lithotron device are already being used in the treatment of kidney- and gallstones.

Methods  In 7 in-vitro setups (fragmentation: sieve, propulsion, gelatin, ducts of cattle tissue, combinations) more than 800 stone models (casting and drum stones, human salivary stones) were used to test efficacy (number of impulses, time until fragmentation) and therapeutical safety (damage indexed integrating tear length and number, duct widening, number of impulses until perforation, propulsion) of LL, PL, EKL and EHL.

Results The efficacy of the EKL and EHL was higher than the efficacy of the LL and lower than the PL in 4/6 respectively 2/4 measuring sequences (MS). Fragmentation of casting stones (minutes) took 01:50 ± 00:28 with the PL, with the EKL 02:49 ± 00:37 and 05:12 ± 00:58 with the LL (Mann-Whitney-U-Test, p<0,01, Cohen’s d>0,80). In 2/3 MS, EKL was more efficient than EHL. LL and EHL caused the lowest propulsion; the highest was observed for PL (in 2/2 measuring sequences). In the gelatin experimental set-up, the laser induced the most extensive damage. 1 impulse of the LL and EHL were sufficient to cause a perforation (2/2 MS).

Conclusion  The EKL can be considered as a potential new method for the intracorporeal treatment of salivary stones. EKL’s results for efficacy as well as therapeutical safety lie in the same range as those of well-established methods. Clinical testing appears justifiable.

Conflict of Interest

The authors declare that they have no conflict of interest.

Publication History

Article published online:
12 May 2023