In Anterior Chamber Analysis - Zeiss CIRRUS HD-OCT 500 User Manual

8-54
2660021169012 Rev. A 2017-12
Anterior Segment
Abbreviation
AOD500 Angle Opening Distance at 500 mm: Distance between C and D.
AOD750 Angle Opening Distance of 750mm: Distance between E and F.
TISA500 Trabecular Iris Space Area 500 (mm
forming a circuit through points A,C,D, and B.
TISA750 Trabecular Iris Space Area 750 (mm
defined by the sides A, C, D, B, and C, E, F, D.
SSA Scleral Spur Angle: This is a measure of the angle formed by CAD, that is, the angle
measured at the conjunction of lines CA and AD. Note that line AD, which is not
shown in Figure
500 iris endpoint (point D).
Click the Add Left IC Angle button
right iridocorneal angle tool on the image.
The iridocorneal angle tool is a trapezoid that can be moved and adjusted to graphically
display angle opening distance (AOD) at 500mm and 750mm, trabecular iris space area at
500mm and 750mm, and sclera spur (SSA) angle. A table based on the dimensions of the
trapezoid is displayed with values for the AOD 500 and 750, TISA 500 and 750, and SSA
parameters.
Move the pointer to any line on the trapezoid, and then drag the tool to an area of interest.
Move the pointer to the end of any line on the trapezoid until it changes to a yellow circle,
and then drag the end.
Example:
1. Identify the scleral spur and place point A of the IC Angle Tool at the scleral spur.
2. Adjust point C (AOD 500 corneal endpoint) to touch the corneal endothelium.
3. Adjust point E (AOD 750 corneal endpoint) to touch the corneal endothelium.
4. Adjust point F (AOD 750 Iris Endpoint) to touch the iris.
5. Adjust point D (AOD 500 Iris Endpoint) to touch the iris.
6. Adjust point B (Scleral Spur Iris Endpoint) to touch the iris.

In Anterior Chamber Analysis

1. Select Add Left Angle Tool or
viewport of the Anterior Chamber Analysis screen.
2. Place point A of the Angle Tool at the scleral spur.
3. Adjust point B to touch the corneal endothelium.
4. Adjust point C to touch the iris. See
Measurement
2
): The area of the polygon defined by the sides
2
): The sum of the areas of the two quadrangles
8-38, is the line connecting the Scleral Spur (point A) to the AOD
or Right IC Angle button
Add Right Angle Tool above the main
Figure 8-39.
CIRRUS HD-OCT User Manual
to place the left or