JOHN D. ZDRAL MD (Medical Director) | JOHN E. ESSER, OD
High-definition imaging devices have provided a new and detailed look into the structures of the human eye, and are now utilized on a regular basis to study the cornea, retina, optic nerve, and the optics of your eye.
Advanced imaging at the Fullerton Eye Institute falls into three main categories:
Optical Coherence Tomography or OCT
OCT is a non-invasive imaging test that uses light waves of specific wave lengths to take detailed cross-sectional images of the retina and optic nerve. This allows your eye doctor to map and measure the layers of the retina and nerve fiber layers with incredible microscopic detail. This is particularly useful in screening and evaluating changes in the macula of the eye for macular degeneration. It also allows incredible precision in monitoring the optic nerve for any progressive damage in cases of glaucoma. The OCT machine will scan your eye in 1-2 minutes without touching it, and micron level resolution in two and three dimensions. OCT provides a straightforward method for assessing retinal cell layers, diabetic macular edema, and photoreceptor integrity.
Measuring the topography of the eye is essentially mapping the surface of the cornea, and measuring the curvature. Since the cornea is responsible for about 70% of the optical power of the eye, topography is of critical importance in determining the quality of vision and the corneal health. Corneal topography can be employed for diagnostics in measuring amounts of astigmatism or irregular contours of the surface. Conditions that can be studied include keratoconus, irregular astigmatism, scar formation, and other corneal irregularities. Topography is also critical in the pre-operative evaluation prior to cataract surgery.
Visual Field Testing
Mapping the visual field pattern requires a specialized device known as the visual field machine, also known as perimetry testing. To do this test, you will look into a bowl-shaped instrument, and you will see lights projected onto the screen. You press a button when you have identified a light, and this yields a mapping of you overall field of view. A visual field test can determine if you have blind spots in your vision, and demonstrate the pattern. Field defects can be present in stroke patients, and also found with pituitary gland disorders, central nervous system problems (such as a tumor), or optic nerve damage from various causes. The most common use for the visual field test is to monitor field loss in cases of glaucoma. The test is typically done at least once per year to monitor for any progression or worsening of the overall pattern. The test is very precise, and will retest each individual point to verify the accuracy of the measurements. A test will usually take approximately 15-20 minutes to complete, and does not require dilation of your eyes.
Eidon Retinal Imaging System
Takes ultra high resolution photos of your optic nerve, macula and retina. This device sets a new standard in retinal imaging and allows for the early detection of many retinal pathologies.
Eidon Retinal Imaging is so detailed and precise, it has become a routine part of all diabetic screening and evaluations.