Glaucoma is a major cause of blindness affecting more than 3 million Americans 40 years and older.
This disease is three to four times more commonly seen in African Americans and Hispanics compared to Caucasions. All races are at higher risk above age 60 years old.
Also, patients with a family history of glaucoma or those with long term steroid use all face increased risk of developing glaucoma.
Most cases of glaucoma involve the drainage system of the eye clogging intraocular pressure, in front of the lens, grows to push back and damaging the optic nerve in the back of the eye.
The optic nerve, made of about a million nerve fibers, process info from the retina. The optic nerve is located in the back of the eye and is responsible for sending visual information, via the 2nd cranial nerve, to the visual cortex of the occipital lobe of the brain. The brain then perceives vision.
How Is Glaucoma Diagnosed?
Diagnosis of glaucoma is made in large part based on looking at the optic nerve head. Normally a physical depression called a cup is seen.
This cup diameter is then compared to the diameter of the whole nerve head/disc. In healthy optic nerves, the cup to disc ratio is ⅓ or 0.3.
Glaucoma causes nerve fibers along the rim of the nerve head to stop functioning, making the cup/disc ratio grow. Fundus photography is the test that can measure the cup to disc ratio by looking in the back of the eye.
Other tests to verify glaucoma include ocular tonometry which checks the intraocular pressure which normally is 12-22 mmHg.
Peripheral vision is often compromised with glaucoma and peripheral field tests are performed. Because peripheral vision is compromised, rod photoreceptors are impacted to a greater extent than cones.
This leads to difficulty with driving at night and trouble with contrast vision. Contrast sensitivity testing is helpful in detecting these changes.
The Four Types Of Glaucoma
There are four types of glaucoma but open-angle glaucoma accounts for 90% of all cases. This type involves drainage structures, called the trabecular meshwork, being clogged.
Normally fluid is made by ciliary bodies behind the iris. Fluid then flows through the pupil into the front of the eye forming aqueous humor.
The fluid flows out through channels called trabecular meshwork and into veins of the sclera. This increases intraocular pressure and damages the optic nerve. Other forms of glaucoma are much less common.
They include a) closed-angle glaucoma involves a defect in the trabecular meshwork so fluid cannot drain properly.
Closed-angle glaucoma can lead to a sudden increase in eye pressure along with severe eye pain, blurred vision, nausea, and vomiting.
b) normal-tension glaucoma is also less common and includes damage to the optic nerve even though intraocular pressure in the eye is between 12-22 mm Hg.
c) Juvenile glaucoma can be present at birth and is a congenital form of closed-angle glaucoma usually requiring surgical intervention.
Treatments For Glaucoma
Western treatments include eye drops that are prostaglandin analogs that work by increasing the outflow of fluid from the eye and reducing pressure.
Surgical and laser trabeculectomy also work to improve drainage from the front of the eye. So why do patients that have generally well-controlled eye pressures still often see a decline in vision?
The answer is there is more than pressure to control symptoms. Specifically improving blood flow is essential to restore function back to optic nerve cells.
Western approaches to address glaucoma do not address this fundamental problem. From the publication Evid Based Complement Alternative Med. 2011 Mar 7th by Shin Takayama et al, research was done on the effects of acupuncture on retrobulbar circulation and intraocular pressure (IOP) with glaucoma subjects.
The conclusion was that significant improvement in blood flow to the choroid in the back of the eye along with drops in IOP was demonstrated due to the effects of acupuncture.
The study was the first of its kind to show the effects of acupuncture on blood flow in the eye. By restoring circulation, optic nerve cells that were dormant or damaged can often be revitalized to act like normal optic nerve cells.
Thus restoring peripheral vision, night vision and contrast vision in up to 85% of our patients who get a series of at least ten treatments.
If you or a loved one suffers from diminished vision, please call our office to discuss addressing your degenerative eye care needs.