Glaucoma is a chronic eye condition that can eventually lead to vision loss and blindness. While there are treatment options available, there is no definitive cure for glaucoma. The treatment for glaucoma is monitored closely to evaluate for potential worsening of the condition. The tests which can be used to monitor for these changes include checking the eye pressure, a laser scan of the optic nerve and retina, and a visual field test. Each of these tests is used routinely for assessing the risks of progression in cases of glaucoma.
Progression of Glaucoma
When glaucoma is untreated or under-treated, there is a risk of progression. This progression includes damage to the fibers in the optic nerve.
This type of damage occurs slowly over time and leads to reduced peripheral vision and eventually reduced central vision.
It is scarce to have any sudden changes which would prompt noticeable symptoms from glaucoma.
Eye Pressure and Glaucoma
Traditionally, the biggest risk factor for glaucoma or glaucoma damage is the pressure inside of the eye.
This pressure is the cause of nerve damage and vision loss in glaucoma.
At a routine eye exam, the eye pressure is checked using an air puff, handheld device, or other instruments.
If the eye pressure is too high, there can be damage to the nerve. So eye pressure is checked regularly when monitoring glaucoma.
There are different methods of checking eye pressure but the most accurate and most commonly used is a technique called applanation tonometry.
This uses a numbing drop and yellow dye to allow the doctor to determine the pressure inside the eyes.
OCT Scans Can Help Diagnose and Monitor Glaucoma
A new device called an OCT (optical coherence tomography) can be used to image the back of the eye including the optic nerve and the retina.
These scans can measure the thickness of these structures to a microscopic level and have been shown as an important tool in monitoring small changes in glaucoma.
Glaucoma causes the optic nerve fibers to thin due to atrophy of the tissue and this is shown on an OCT scan when compared to previous scans.
Additionally, an OCT can be a way to distinguish damage to the optic nerve due to glaucoma from other eye conditions like optic neuritis or optic neuropathy.
Visual Field for Glaucoma
While an OCT can monitor for physiological changes to the optic nerve and retina, a visual field monitors for functional changes.
This test uses a machine to assess the extent and sensitivity of the field of vision. If there is an area that has had nerve damage there is likely a corresponding visual field defect.
A visual field defect is an objective loss of function and shows that there has been enough progression to lead to permanent changes in the eyes.
Importance of Monitoring Glaucoma
With the numerous ways of testing the eyes for changes from glaucoma, the most important aspect becomes following the directed appointment times for follow-up testing.
These tests are best when used as a continuous comparison over time. This means that there is a need for multiple tests – often every three or six months – to assess the condition effectively.
0 Comments