7.        Meibography: imaging and analysis of the meibomian glands are currently done with three targets in mind – to measure the area of the tarsal plate covered by the meibomian glands and their ducts (meiboscore), the tortuosity of the glands and the length or shortening of the glands. These three are scored on a scale of 0 (no disease) to 3 (maximum disease) and the sum of these scores are called Meibograde (0 no disease to 12 maximum disease). OSDx® uses near-infrared radiation to image the glands. Imaging is possible for both upper and lower tarsal glands after eversion of the lids. The small footprint of the device allows you easy access to the eye for everting the lids.
   1. The Meibography capture and analysis area is described below
   2. If you have a first generation device use the red touch switch at the back of the device to switch on the infrared. For second generation and later devices selecting the Meibography mode from the software will automatically switch to infrared.
   3. To start capture, click on the start camera button.

 

 

3.    The live video window shows low contrast images as are seen by the camera. To help you capture great quality images every time without fail and help you assess the uniformity of focus before saving an image for analysis, OSDx® provides a Focus assist window. You can see the glands well demarcated in the focus assist window. Ensure that the lid is well flattened to ensure a uniform quality of focus – this will help in subsequent image processing.
4.    You can increase or decrease the overall brightness of the image in the Focus assist window by changing the value of the brightness scroll bar (centre – no change, left – darker image, right – brighter image) which is set to -150 by default.
5.    You can save up to four images for analysis per eye per lid. Saving can be done either by clicking the Capture button on the MBG toolbar or by pressing any key on the keyboard of your PC. Capture will stop automatically once you have saved four images. You can click any one of the four saved images to move them to the Focus assist window for further processing. If you are not happy with any of the images and want to start the process of capture again, simply press the start camera button again.
6.    OSDx® allows you to mark the lid area for subsequent calculation of meiboscore (percentage of lid area covered by glands). This is not auto-detected using image processing techniques to give you more control and ensure clinical accuracy. You can leave out poorly illuminated, out of focus or over-exposed areas from the analysis giving you more consistent scores. To mark the lid area under analysis click on the Mark lid button on the MBG toolbar. When selected (i.e. in marking mode) this button will turn red. You can then click on the image in the focus assist window to mark out the lid area. A maximum of 20 points can be marked to delineate the lid area. You can move a point after marking by hovering over the point and dragging it when the cursor changes to a cross. After marking at least 5 points the software starts drawing a spline to define the area of analysis. Note that you do not need to mark all 20 points – only as many as are required to mark your area of interest.
7.    To delete all marks and start afresh click the Clear points button on the MBG toolbar
8.    Once you are happy with the delineation of the area under analysis click the Get score button on the MBG toolbar. A small progress bar will appear above the Focus assist window to show the progress of the analysis and after a short wait a score will appear in the Meiboscore box. The gland loss percentage is calculated automatically and the value appears in the MG loss box. Both values are in percentage of the region of interest marked by you.
9.    For a look under the hood for the meibomian gland segmentation process you can click on the Advanced button in the drop down of the Get score button. You will get a popup window showing eight different segmentations using different settings. Normally the automated process accepts the processing which yields the highest score but you can choose any other segmentation that you think best represents the glands. To do this simply double click on the image you select in this popup window. To close this window and use the default segmentation simply click on the Cancel button in the popup window.

3.    To save the image in the Focus assist window to your PC click the Save image button on the MBG toolbar.