Spectral-Domain OCT

Eye tracking makes the difference

In the new world of spectral-domain OCT imaging, being fast isn’t good enough. Spectralis^® scans 100 times faster than time-domain OCT and 40% faster than most other spectral-domain instruments. And we don’t really think that is important.

Why? Because eliminating motion artifact is the key to quality imaging. Even the fastest spectral-domain volume scan needs a couple of seconds to complete. That is more than enough time for micro and macro saccades, not to mention blinks, to blur a scan.

OCT without Eye Tracking Spectralis^® with TruTrack™ Eye Tracking

To solve this, we took our experience with HRT and HRA TruTrack™ image alignment software and used it to create a new way of imaging: tracking laser tomography. Rather than just madly scanning the retina as fast as possible, we used our well-developed image alignment software to track the eye. By tracking eye movement, we could eliminate motion artifact that caused blurring in OCT images.

We always capture a high resolution fundus image with every SD-OCT cross sectional scan. Not only does this provide clear documentation of the surface of the retina, but it gives a real time reference for locating the SD-OCT scan.

The benefits and the images are clear! Tracking eye movement eliminates artifact, enables noise reduction and allows the instrument to scan in the same location at a follow-up exam – without relying on the operator to pick the spot.

As we look to the development of new therapeutics in all areas of eye care, tracking change over time will be the key to good clinical outcomes. And we should know. We discovered the advantages of outrunning saccades in 1991 with the Heidelberg Retina Tomograph. The Ocular Hypertension Treatment Study showed how valuable this was as the HRT predicted outcomes up to 8 years in advance of visual fields and expert assessment. The success was due to image alignment and eye tracking.