Glaucoma Evaluation in OKC and Edmond
Some forms of glaucoma produce little to no symptoms in their early stages, meaning you may be unaware there is a problem until it is too late. Once damage to the optic nerve and glaucoma-induced vision loss has begun, those parts of your vision cannot be recovered. However, if caught early, glaucoma can be treated and controlled to prevent further permanent vision loss.
For this reason, it’s important to schedule yearly comprehensive eye exams with your doctor so that glaucoma can be detected early and treated appropriately. The Dean McGee Eye Institute (DMEI) treats more than 5,000 patients with moderate to advanced glaucoma each year. Many of these patients could have benefited from much earlier diagnosis or more careful and precise monitoring of their risk factors for developing glaucoma.
Methods Used During a Glaucoma Evaluation
At DMEI, our team of ophthalmologists performs comprehensive glaucoma screenings to achieve a full and accurate assessment of your unique situation. We use several different methods to accurately assess whether you have glaucoma as well as your risk of developing the disease later on. All tests conducted during a glaucoma evaluation are painless, non-invasive, and safe.
Measurement of Intraocular Eye Pressure
Elevated intraocular pressure (IOP) is a major risk factor for the development of glaucoma, as optic nerve damage becomes more likely as IOP increases. During your glaucoma evaluation, your doctor will measure your IOP using a procedure called tonometry. After administering eye drops to numb your eyes, your doctor will use a device that applies a small amount of pressure to your eye to measure its internal pressure.
Your doctor will also measure your corneal thickness using a test called pachymetry. This is necessary to stratify one’s risk of developing glaucoma, as thinner central corneas are associated with increased risk of developing glaucoma.
Measuring intraocular pressure at different times of day may be necessary in some cases to achieve an accurate diagnosis.
Assessment of the Optic Nerve
To assess the health of your optic nerve, your doctor will use a non-invasive slit lamp biomicroscope to detect changes in the nerve consistent with the diagnosis of glaucoma. Your doctor may also use stereographic photography or more advanced imaging techniques of the optic nerve, such as optical coherence tomography (OCT).
OCT allows us to view the nerve fiber layer which sends information from cells in the retina that capture light called photoreceptors to the brain where this information is interpreted as an image. These instruments may show damage from glaucoma at a much earlier stage than can be detected by other methods. Earlier detection and intervention can allow your doctor to slow the progression of glaucoma more quickly.
Evaluation of the Peripheral Visual Field
As your optic nerve is damaged by glaucoma, defects in your vision can result, most often involving your peripheral vision. Your peripheral vision is measured using standard visual field testing. It should be noted that glaucoma-related visual field loss may not become evident until significant optic nerve damage is present.
At DMEI, we use several advanced techniques, including short-wavelength automated perimetry, which can detect damage to the visual field from glaucoma earlier than some standard tests. During a short-wavelength automated perimetry test, your doctor will use an instrument that projects blue stimuli onto a bright yellow background. Your ability to see the blue stimuli allows your doctor to detect defects in your visual field.
Additionally, software incorporated into our visual field machines can help detect worsening of peripheral vision by comparing all stimulus points either over time or relative to your most recent visual fields. This allows our glaucoma specialists to determine if your glaucoma is functionally stable or worsening.