29
PERFORMING A
-
SCANS (CONTACT)
WARNING:
Exercise caution when coming into contact with a patient
’
s eye. To avoid
potential injury, use minimal pressure when applying the probe or adjusting its position.
Only make minor position adjustments while in contact with the eye. If significant position
adjustment is necessary, remove the probe from the eye and then reapply.
WARNING:
Before each procedure, the ultrasound probe must be cleaned and disinfected.
Refer to the
Cleaning and Disinfection
section.
NOTE:
Refer to the
Alignment Ranking System
and
Video Buffer Full
sections for more
information on these topics.
1.
Create a new patient or select an existing patient on the Patient Screen.
2.
Select the A
-
Scan Screen tab. If necessary, click the
[CHANGE EYE]
†
button to change the
eye being measured (OD or OS).
3.
Select the
“
Contact
”
radio button on the right
-
hand side of the screen. Select the name of
the Operator performing the measurement from the drop
-
down box.
NOTE:
If the operator is not listed in the
“
Operator
”
drop
-
down box, add the new operator
by selecting
Preferences > Operator
and clicking the [
NEW]
button.
4.
Select the correct Lens and Vitreous type for the eye to be measured.
5.
Adjust the compression lockout sensitivity track bar (Comp) to the desired setting. Higher
Compression Sensitivity will decrease the amount of error due to corneal compression, but
will make it more difficult to obtain measurements.
NOTE:
Refer to Page 27 for more information on Corneal Compression Sensitivity.
6.
Seat or recline the patient in a position comfortable for both Patient and Operator. Head
movement must be minimized during the exam. Anesthetize the eye and have the patient
fixate with both eyes on a spot on the ceiling or wall.
7.
To Start scanning
†:
-
Click the
[START SCAN]
button; or
-
Press the
Space Bar
(on the keyboard); or
-
Press the
Foot Pedal
(Single Pedal accessory); or
-
Press the
Left Foot Pedal
(Double Pedal accessory)
A waveform will be displayed on the screen, but the unit will not begin recording.
8.
Stabilize the hand holding the probe to minimize indentation of the cornea or
excessive movement. Typically, this can be done by resting a palm on the cheek or
forehead of the patient.
9.
The transducer should be held perpendicular to the surface of the eye as it approaches the
cornea. Observe the approach from a vantage point that allows a view across the
topography of the eye. This method aids in seeing the exact moment when the probe
contacts the cornea, allowing the user to minimize indentation of the cornea.
10.
Gently apply the probe tip to the center of the cornea. The unit will start beeping at the
moment of contact, which indicates coupling has been achieved. Minimize indentation of
the cornea.
NOTE:
Stopped or intermittent beeping indicates that the probe tip has been removed from
contact with the eye or is not properly coupled. Re
-
attempt application of the probe.
†
This command may be executed through voice control. Refer to the
A
-
Scan Voice Controls
section.
