User's Manual

Lumenis
®
Pulse
TM
50H / 100H Laser Systems Laser Power Parameters
UM-20006520DE, Rev. A Page 13
Holmium laser systems can deliver the same average power at different
settings to achieve different laser tissue effect. Changing the energy of
each pulse can be described as the “bite size” of the laser effect, whereas
the frequency as the “bite rate”. For example, setting the system at 50W
can be performed using the following sets of parameters: 2.5J at 20Hz or
2.0J at 25Hz.
When working with calculi, for example, these different settings may
affect the stone by breaking the stone into particles versus disintegrating
the stone into fine dust. The selection of the appropriate energy and
frequency settings is dependent on the procedure and specific target
tissue.
Each pulse is delivered at a specific time frame, leading to fast heating
rise in temperature of the target tissue. By increasing the pulse duration,
the time frame of energy delivery to the tissue changes and thereby
changing the temperature profile of the tissue. A different temperature
profile may lead to a heating rather than a vaporizing effect and is useful
for example when blood vessel coagulation is desired.
The selection of appropriate power parameters and optical fiber is
dependent on the procedure and the specific patient condition. It is
recommended that you become familiar with laser characteristics and
techniques by attending courses and consulting with colleagues in order to
utilize the lasers capabilities in a safe manner.