The document discusses electrohydraulic lithotripsy (EHL), a technique that uses electric sparks delivered in pulses between electrodes at the tip of a fiber to create shock waves. These shock waves oscillate and generate sufficient pressure to fragment stones by inducing the immediate expansion of surrounding liquid from the electric sparks. Modifications to the acoustic lens of an electromagnetic lithotripter produced a broader focal zone and improved pressure waveform, demonstrating better stone fragmentation in vitro.

3. The principle of electrohydraulic
lithotripsy (EHL) is the creation of an
electric high-voltage spark between two
isolated electrodes located at the tip of a
fiber. The electric sparks are delivered in
short pulses that create an immediate
expansion of the surrounding liquid,
inducing a spherical shock wave. The
shock wave oscillates, generating
sufficient pressure to fragment the stone.

4. we have modified the acoustic
lens of an EM lithotripter to
produce a broader focal zone and
an idealized pressure waveform
more closely resembling that of
the HM3. Evaluation of this
modified lens in vitro has
demonstrated significantly
improved stone fragmentation.

5. Theoretical formulation of the
electromagnetic field
distribution in the focal region
of an elliptical reflector that has
its surface coated with an
unmagnified collisional plasma
layer

6. Piezoelectric Effect is the ability of
certain materials to generate an
electric charge in response to applied
mechanical stress. The word
Piezoelectric is derived from the
Greek piezein, which means to
squeeze or press, and piezo, which is
Greek for “push”