LIGHTMED TruScan Pro
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Operator’s Manual Rev. No. 01
Page
26
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109
Section 4
Principles of Operation
4.1
General Description
The acronym LASER stands for Light Amplification by Stimulated Emission of Radiation. The light
beam from a laser is a valuable tool for medical applications, which possesses the characteristics
mentioned below:
•
The beam from a laser is collimated. It does not diverge and can maintain a constant diameter
over a long distance. The laser beam can be focused to a very small spot with high energy
and power densities.
•
The beam is monochromatic. It is a single wavelength beam that produces predictable and
reproducible tissue effects.
•
The light waves are coherent. They are in phase with each other and do not interfere and/or
generate losses in energy.
The TruScan Pro laser system is an ophthalmic laser suitable for performing the following clinical
procedures:
•
Retinal photocoagulation
•
Pan retinal photocoagulation
•
Endo photocoagulation
•
Macular treatments
•
Laser trabeculoplasty
This system can have up to four wavelength configurations. Depending on the laser wavelength
selection, the appropriate laser beam is generated from the console laser aperture. A red aiming
beam is used to position the treatment laser beam prior to delivering to the patient’s cornea.
The operator must first confirm that the patient meets the treatment requirements (indications and
contraindications) before proceeding with any treatment. Typically, the operators or their
assistants would verify that the laser and LDU are operating correctly before positioning the
patient on the chinrest to avoid any inconvenience to the patient. This verification process includes
checking the laser output and alignment.
The operator must set the laser power and pulse interval whenever the system is turned ON. It is
the operator’s responsibility to set the acceptable power levels and pulse intervals. It is
recommended to always start with a lower power and shorter pulse intervals to reduce the risk of
unintended patient injury. By default, the laser system is set to 200 mW power, 20 ms pulse
duration, and OFF pulse interval. These settings can be altered and saved by the operator to
satisfy their preferences. Conversely, the operator can select a repeat pulse mode where the
laser is pulsed repetitively according
to the operator’s requirements. However, in this mode, the
laser is in the operator’s control via the footswitch; once the footswitch is released, there will be
no laser output.
Laser light is primarily used as a source of energy to heat up the tissue, producing
photocoagulation effects. The laser beam is applied directly to the tissue, which is then absorbed
by the melanin pigment within the retinal pigment epithelium and the choroid. This absorption
converts the light energy into heat energy, which raises the temperature of the tissue being
treated, producing thermal coagulation of the protein. This laser beam is readily transmitted
