Iridex OcuLight Symphony, Operator'S Manual

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57
Clinical & Safety
Clinical Applications
CAUTION
Take particular care when
examining infants or
aphakic patients.
NOTE
Avoid dilating the patient’s
pupils unless necessary for
treatment.
WARNING
The relationship between
spot size and resultant
power density is not linear.
Halving the spot size
quadruples the power
density. The physician must
understand the
relationship between spot
size, laser power, power
density, and laser/tissue
interaction before using
the OcuLight Symphony
Adapter.
Indications for clinical use
The OcuLight Symphony Adapter, when connected to the
OcuLight SLx/GLx/TX console, provides diagnostic and therapeutic
capability of retinal photocoagulation and for laser trabeculoplasty in the
treatment of glaucoma.
Contraindication
Do not treat albino patients.
Recommended procedure for clinical use
This section contains general guidelines and is not intended to suggest
treatment techniques. Qualified physicians should review the available
literature presented in clinical papers before using the OcuLight
Symphony Adapter.
Power density and spot size
Tissue response to laser light is primarily determined by power density.
Power density (Watts/cm
2 ) is laser power (Watts) divided by the area (cm 2 )
of the illuminated spot; therefore, you can increase power density either
by increasing the laser power or by decreasing the spot size.
Power and duration
If you are uncertain of tissue response, always start with the lower power
settings and increase the power until you observe satisfactory clinical
lesions.
Shorter pulse durations require higher power densities to create a burn;
however, very short pulse durations can be potentially dangerous.
Red aiming and treatment beams
Since the red aiming beam and the treatment beam come to focus at the
same optical point, ensure that the aiming beam is always in sharp focus
during laser delivery. An out-of-focus spot may not produce a clinically
satisfactory lesion.