The Most Advanced Eye Care Technology
Our vision specialists utilize cutting-edge technology to provide superior eye care and treatments.
Humphrey Visual Fields
Visual field tests assess the potential presence of blind spots (scotomas), which could indicate eye diseases. A blind spot in the field of vision can be linked to a variety of specific eye diseases, depending on the size and shape of the scotoma. Many eye and brain disorders can cause peripheral vision problems and visual field abnormalities. For example, optic nerve damage caused by glaucoma creates a very specific visual field defect. Other eye problems associated with blind spots and other visual field defects include optic nerve damage (optic neuropathy) from disease or damage to the light-sensitive inner lining of the eye (retina). Brain abnormalities such as those caused by strokes or tumors can affect the visual field. In fact, the location of the stroke or tumor in the brain can frequently be determined by the size, shape and site of the visual field defect. Learn More About Humphrey VF
The Heidelberg Retina Tomograph (HRT)
The Heidelberg Retina Tomograph (HRT) is a confocal scanning laser ophthalmoscope. A laser light scans the retina in 24 millisecond sequential scans, starting above the retinal surface, then capturing parallel images at increasing depths. The stacks of images can be combined to create a three-dimensional (3D) topographic image of the retina. Images are aligned and compared using TruTrack™ software for both individual examinations and for detecting progression between examinations. The same technology is used in the HRT Retina Module.
3D Optic Disc Topography vs. Tomography
When applying the technology to glaucoma, the HRT takes data from a 3D stack of tomographic images of the optic nerve and retinal nerve fiber layer (RNFL), aligns the images and computes a 3D topographic map of the surface of the retina. This 3D topographic map is analyzed for signs of glaucomatous damage and the results are displayed on either a single eye examination report or on an OU examination report.
24-Millisecond Scan Helps Avoid Eye Movement Artifacts
The HRT scans the retina in 24-milliseconds, faster than most involuntary eye movements (micro saccades occur in 30-50 milliseconds) and faster than voluntary eye movements (macro saccades occur in 150 or more milliseconds). Each scan is composed of 384 x 384 pixels for a total of 147,456 data points covering a 15-degree area of the retina. Other technologies, such as time-domain OCT, scan slower than 24-milliseconds, contributing to motion artifact (blurring of the data).
TRUTRACK™ Image Alignment Provides Accuracy In Single Exams
TruTrack™ is a proprietary software which aligns images within examinations and between examinations. The software uses anatomical features (such as blood vessel patterns) and other image characteristics to align the images. Good image analysis requires both high-quality images (fast scanning) and image alignment. To construct a single examination, the software aligns a stack of individual scans. Each scan is examined for image quality and if any are found to be outside of acceptable quality indices, the scan is discarded from the image set. Three sets of scans are automatically captured at each acquisition, providing data redundancy. The three sets are used to create a final composite image for analysis. Only Heidelberg Engineering offers retinal imaging technology which automatically discards low-quality scans.
TRUTRACK™ Image Alignment Detects Image Variability And Disease Progression
The Topographic Change Analysis (TCA) software uses TruTrack™ software to look for signs of disease progression. By examining the variability of the three scan sets in an individual examination, sequential examinations can be compared for significant differences by eliminating differences due to image variability such as eye movements and fixation losses. More than simple serial analysis which only subtracts the difference between two examinations, the software identifies statistical differences between examinations, accounting for the within-examination variability. This approach has been validated against a patient series with more than ten years of follow-up.