Glaucoma is one of the leading causes of blindness in the United States. It is a condition in which the nerve of the eye is damaged due to uncontrolled pressures from within the eye. The damage could result in a painful eye (seen in narrow angle glaucoma or acute angle close glaucoma), but more often, results in slowly progressive, painless loss of vision (seen in the more common open angle glaucoma). Glaucoma damages the peripheral vision, so patients may develop significant damage to the nerve without noticing a change in their central vision. This damage from glaucoma is irreversible. However, if diagnosed early, the vision can be maintained and glaucoma progression, halted.
Diagnosis of Glaucoma
The diagnosis of glaucoma has changed over the years. Historically, any intraocular pressure above 21 mmHg was considered to be the definition of glaucoma. Today, it is clear that an elevated intraocular pressure is just a risk factor for glaucoma. An elevated intraocular pressure may be seen in normal patients and a low intraocular pressure may be seen in glaucoma patients.
The Visual Field Test is currently the gold standard for evaluating the status and progression of glaucoma. It evaluates the peripheral vision by having patients respond each time they see a projected light in the peripheral visual field. Both the diagnosis and the evaluation of progression of glaucoma can be made with this test.
The OCT-HD Nerve Fiber Analysis is the latest technology for evaluating the status of the optic nerve. It directly measures the thickness of the nerve fiber layer emerging from the optic nerve. It is thought that this instrument may help to catch glaucoma years earlier, before vision loss actually occurs. Every patient evaluated by either Dr. Decker or Dr. Yang will receive an OCT-HD nerve fiber analysis to help refine their ocular assessment.
In a landmark study published in Archives of Ophthalmology (June 2002), the thickness of the cornea was found to play a vital role in glaucoma. Having a thin cornea puts a patient at much higher risk for developing glaucoma. As a result of this study, patients with glaucoma as well as patients suspected of having glaucoma should have corneal pachymetry performed in order to determine their corneal thickness.
Lastly, both Dr. Decker and Dr. Yang use state-of-the-art digital 3-dimensional photography to document the optic nerves. This captures not only the appearance, but also the contour and shape of the optic nerve. These elements are critical in following the stability of the nerve.
Treatment of Glaucoma
There are many treatment options available for glaucoma patients. For most patients, eye drops are the first treatment of choice. There are numerous, excellent medications available and both Dr. Decker and Dr. Yang are well versed in the nuances of each medication as well as their potential side-effects.
More and more patients are opting for laser treatments to lower the intraocular pressures. There are different types of laser treatment for the different types of glaucoma. This includes laser peripheral iridotomy, argon laser trabeculoplasty, and selective laser trabeculoplasty.
For patients requiring cataract surgery, there are surgical interventions under the category Minimally Invasive Glaucoma Surgery (MIGS) that can be performed during cataract surgery, to help with improving glaucoma control. In the more advanced cases, where the glaucoma is not well-controlled with either medications or laser treatment, there are more invasive surgical options available. At this stage, Dr. Decker or Dr. Yang can discuss with each patient the options best-suited for each individual’s needs.