OCT View Tools

Several tools are available for the OCT views. To access these tools, select View Tools in the side panel.

Thickness Map

The Thickness Map provides tools to visualize the thickness between encoded boundary layers.

Type

Available for the Retina and 3D views. Where multiple layers are encoded, use Type to select the desired view. The Type determines which retinal layers are shown as the top and bottom layers.

Volume

Available for the 3D view. Select this option to view the volume in the 3D viewport. If the Volume option is not selected, the top and bottom layers are shown in a pack mesh.

Top Layer, Bottom Layer

Available for the 3D view. Both the top and bottom layers are shown by default. To hide the top or bottom layer, deselect the Top Layer or Bottom Layer option. If both the top and bottom layers are hidden, the tissue above the top layer and below the bottom layer is shown.

Greyscale Tissue

Available for the 3D view. Select this option to view tissue on the top layer.

Depth Map, Legend

Available for the Retina and ONH views.

For the Retina view, the depth map applies a color thickness map to the SLO. A legend is available with the colors used for the various depths (in microns). Smaller depths are shown in blue and deeper depths are shown in red.

For the ONH view, the depth map applies a color map to the cup and disc area on the SLO. A legend is available with the colors used for the various depths (in microns). Smaller depths are shown in blue and deeper depths are shown in red.

Gauge

Displays a gauge (in mm) for the SLO. The gauge is shown on the right side of the SLO.

NFL

Available for the ONH view. When Depth Map and NFL are selected, the depth map on the SLO image shows the depth between the boundary layers identified by the names ILM and NFL.

Confidence

Available for the Retina and ONH views. For each slice, a color-coded label showing the confidence level regarding the slice location is shown on the right side of the SLO.

Range

Available for the Retina and ONH views. You can change the range used for the depth map. Use a smaller range to maximize the color range when viewing thinner layers.

Contours

Available for the Retina view. You can view a step function of the depth (25, 50, or 100 μ).

Samples

Available for the Retina and ONH views. Select a sample (such as ILM or RPE) to view the slices that contain this type of segmentation layer. The slices are shown as horizontal lines on the SLO image in the top-left viewport.

Enface MPR

Available for the Retina and ONH views.

  • When the Enface MPR option is selected, an MPR image with a coronal view of the OCT slice stack is shown in the main (top-left) viewport. If the reference lines in either of the cross-sectional viewports are modified, the MPR image in the main viewport will be updated accordingly.
  • When the Enface MPR option is not selected, a 2D SLO image is shown in the main (top-left) viewport. If the reference lines in either of the cross-sectional viewports are modified, the corresponding reference point will be updated on the SLO image.

The Enface MPR option is selected by default. To remove it, deselect the Enface MPR checkbox.

Grid

Available for the Retina view. View a movable grid on the SLO that displays average thickness (in microns) for the selected region. You can choose from several standard ophthalmology grids and move the grid to the desired position on the SLO. Note that the ETDRS, CSME and 6-Field grids are centered on the encoded fovea location. Moving the grid updates the fovea location in the scan to the new grid center.

Statistics per segment (average thickness and volume) are shown in a table in the bottom-right viewport.

Tools

Several tools are provided to view and edit the segmentation results. Editing of the segmentation results is stored in the Draft presentation. To view the original segmentation results without removing your edits, deselect the Draft presentation. To view your edits, select the Draft presentation again.

View thickness for a point

Available for the Retina view. Hover over the SLO to view the thickness (in μ) for any given point.

Clipper

Available for the 3D view. To use the plane clipper, click (or tap) the 3D image, then drag to push the plane in and out.

Edit layer boundaries and cup/disc outlines

You can adjust the position of the encoded layer boundaries in the cross-sectional viewports in the OCT views. The depth map and grid are automatically recalculated based on the encoded data to reflect the revised layer boundaries. Any adjustments to the layer boundaries will be saved as part of the study. To restore the original layer boundaries, select Reset in the View Tools panel.

There is a region of influence that is affected by a boundary layer adjustment in a slice. The adjustment is propagated to the regions close to the adjustment; the propagation is greatest closest to the slice where the adjustment was made and lessens as you proceed farther away from the slice.

To adjust a layer boundary, place the cursor on the desired boundary and redraw. Click (or tap) close to the existing boundary, then drag to draw a new boundary line. You can edit the boundaries in any of the cross-sectional viewports in the OCT views.

In the ONH view, you can adjust the cup and disc outlines in the SLO. To adjust an outline, place the cursor on the desired boundary and redraw. To restore the original outlines, select Reset in the View Tools panel.

Restore original layer boundaries and cup/disc outlines

Use Reset to restore the original layer boundaries or cup/disc outlines. Note that selecting Reset from the top toolbar will also reset all presentation state changes you have applied, such as zoom and pan.

Reference Data

Use the Reference Data section to compare measurements for the current image to a reference distribution taken from a statistical database.

Color-coded ranges from the statistical database are shown in the Reference Distribution legend. These ranges represent the percentage of images in the database that fall within the same range as the current measurement.

To compare the image measurements to these ranges:

  1. Select Annotate in the Reference Data section.
  2. For the Retina, Retina GCC and ONH views, the legend colors are applied to the measurement table in the bottom-right viewport.
  3. For the RNFL view, the legend colors are applied to the graph in the bottom-left viewport and the graphics in the bottom-right viewport.

Note
The Reference Data section will not appear in the View Tools panel if a statistical database is not currently available for your OptosAdvance implementation.