Anterior segment imaging with the Cirrus HD-OCT is a tremendous benefit to practitioners, as it supplements our skills with gonioscopy to help detect angle anomalies. It is surprising how much pathology can be detected using the Cirrus. With it, we can clearly identify angle structures, including the scleral spur, the canal of Schlemm and Schwalbe's line (Figure 12).
Figure 12. With the Cirrus, we can clearly identify the scleral spur, the canal of Schlemm and Schwalbe's line.
In Figure 13, you can see where the image was projected at the limbus. Broad areas of peripheral anterior synechiae are visible with what looks like an epithelial ingrowth across the angle. This unique ability to image the anterior segment is something we have not had before, and I find it is a useful tool for teaching patients.
Figure 13. Note the broad areas of peripheral anterior synechiae with what looks like an epithelial ingrowth across the angle.
This patient (Figure 14) has a very narrow angle that is occluded in certain areas. An image such as this is a great way to demonstrate why a patient might need a laser iridotomy. You can use the Cirrus HD-OCT with room lights on or off to provide a provocative test for angle closure, and this device also can provide pachymetry readings, using a caliper tool to measure corneal thickness.
Figure 14. Note the very narrow angle. An image such as this can help demonstrate to a patient why he might need a laser iridotomy.
In summary, optical coherence tomography has greatly enhanced our ability to diagnose and manage glaucoma. In addition to improved accuracy, reproducibility and speed, the latest generation of spectral domain Cirrus HD-OCT provides high-resolution images and robust analytical capabilities, enabling us to make more accurate diagnoses earlier and to provide relevant long term follow-up.
