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XI. IMPORTANT NOTES
XI.A. Prescription Device
The
Pachette 2
is a prescription device and is to be used only by or under the
supervision of a licensed physician.
XI.B. Tissue Exposure To Ultrasound Energy
The ultrasound energy emitted by the
Pachette 2
is low intensity and will have no
adverse effects on the patient and/or operator. However, the operator is still cautioned
to perform examinations using the principle of
ALARA
(As Low As Reasonably
Achievable). All examinations should be done so that the patient receives as little
ultrasound radiation as possible. Do not hold the probe against the eye or other tissue
with the system activated except when making a measurement. Do not make
unnecessary measurements.
XI.C. Ultrasonic Intensities
The
Pachette 2
has only one mode, and ultrasonic intensity settings are not under the
control of the operator. Thus, the values below are the values to be expected for a
typical transducer.
In Water
In the Eye*
I
SPTA,mw/cm
²
8.17
7.47
I
SPPA,W/cm
²
13.10
12.00
I
M,W/cm
²
22.90
20.90
* At transducer focus (1 mm from probe tip)
Since the
Pachette 2
is a contact scanner, the energy will always be attenuated by the
tissue when used as recommended. However, since the focal length (point of maximum
intensity) is very short (1 mm), and thus penetration into the eye is limited, the water
values are effectively the same as the tissue values, for all practical purposes.