How to use the Contact Lens Tool.

The Contact Lens feature allows the user to import an image of a patient’s eye with contact lens and assess the fit, movement and ocular health.

A lens perimeter can also be placed on the image to track the perimeter of the contact lens, adjust for image verticality, and rotate for toric alignment.

Once in place the contact lens perimeter tool can be used to measure CL centralisation and toric rotation by degrees.

Identifying Lens Perimeter

Step 1: Select an image to analyse, click 'Contact Lens' and then select 'Identify Lens Perimeter', Figure 1.  

Figure 1

Step 2: The perimeter marker is now displayed on the screen at a default position and size, Figure 2.

Note: The perimeter marker consists of a circle, with markings at the 0°, 90°, 180°, and 270° points to allow resizing, and markings at the 45°, 135°, 225°, and 315° points to allow rotation. 

Figure 2

Step 3: Position, rotate and resize the lens perimeter by clicking the mouse and dragging on the relevant markers.  

Toric lens measurement

Step 1: Select 'Lock' to keep the perimeter in place.

Step 2: Click 'Scribe/Marker'. This is the cursor with a crosshair icon.

Step 3: Using the crosshair, select the position of the 'Scribe/Marker' on the lens.

Step 4: The toric angle is measured and displayed next to the red marker, as well as below the image in the results panel, Figure 3.

Step 5: If required, the red marker can be replaced, and the angle will be automatically re-calculated.

Step 6: To move, resize or rotate the lens perimeter, the user must first de-select the 'Lock' button.

Figure 3