Procedure
During the consultation of a patient showing symptoms of urinary stones the patient’s medical history, physical examination, laboratory evaluation and imaging tests will be tools for diagnosing. Imaging tests, such as x-ray imaging or ultrasound imaging determine the location of the calculi.
The most common treatment for urinary stones, extracorporeal shock wave lithotripsy (ESWL) is not ideal for all stones. The Dornier Medilas H20, a holmium:YAG laser, is a good alternative for very large or difficult to reach stones.
Laser lithotripsy is performed under general anesthesia. The light energy of the laser is transported through a flexible light guide to the stone. For ensuring a safe procedure the laser fiber is observed with an ureterorenoscope. The fiber tip must be in contact with the stone during the firing of the laser. The stone breaking mechanism of laser lithotripsy is a thermal one. The stone fragments when pulses of intense laser light from the Dornier Medilas H20 are applied.
Based upon the principle that Holmium laser energy is strongly absorbed by water, the short laser pulses create a shockwave that causes fragmentation of both ureteral and intrarenal stones. Due to the flexibility and control of the system, different treatment techniques can be applied depending upon the location and shape of the stone. For example, smaller stones can be fragmented directly, whereas with larger concrements, holes are first made in the center, after which the edges can then be fragmented. Finally, the stone residues can be flushed out utilizing the endoscopes rinsing fluid.
