Cataracts vs. glaucoma
Cataracts and glaucoma are two very different diseases that affect the eye. Glaucoma is a disease of the optic nerve while cataracts are an aging change of the lens inside the eye. Because of this, the vision changes people experience with cataracts tend to be more central vision changes, while the vision changes in glaucoma are typically peripheral vision changes. Many people often think that they are related, but in the majority of cases, these two conditions are separate and distinct from one another. In certain special cases, they can be related, but this is not common.
Unlike glaucoma, cataracts will occur in every single person if the person lives long enough. The most common type of cataracts are those that are associated with getting older. Because it is a normal part of aging, every person will get a cataract in their lifetime. It is difficult to predict when a person will get a cataract. Some persons will start to develop cataracts in their forties or fifties while others will not have significant changes until they are in their seventies or eighties.
Early changes from a cataract are typically monitored by an eye doctor until they start to cause a decrease in vision. While every person will develop a cataract at some point in their life, when a cataract needs to be treated is very individual. The only treatment available for cataracts is surgery. Surgical removal of cataracts is done when the cataract becomes visually significant. This means that the cataract has begun to affect the patient’s vision and the patient’s ability to do certain essential tasks such as driving or reading. For most people, cataracts are treated when the best corrected central vision in the eye is 20/30 to 20/40 or worse.
Glaucoma, unlike cataracts, does not happen to everyone. It is more common in patients who have a family history of glaucoma, as well as persons who are Black, Hispanic, or Asian. In glaucoma, the optic nerve of a patient is very sensitive to pressure in the eye, and vision loss can occur when the pressure in the eye is too high for the optic nerve to tolerate. In some patients, the pressure can even be normal, but the optic nerve in these patients is particularly sensitive and so the patient still needs medication to lower the pressure even further.
The one similarity between glaucoma and cataracts is that they are both more likely to occur as an individual gets older. Both glaucoma and cataracts are much more common above the age of 60. There is also one condition in which having a dense cataract can lead to glaucoma and this condition is called phacomorphic glaucoma. This is an uncommon condition that is usually not seen unless the cataract is extremely dense and has caused significant vision loss. While changes from a dense cataract can lead to glaucoma in this one situation, glaucoma does not cause cataracts. They may both occur together, but that is because they are both more common conditions in patients that are older.
The most important part of both these conditions is that they require regular monitoring from an ophthalmologist. An ophthalmologist can both diagnose and treat glaucoma and cataracts. When glaucoma is diagnosed at early stages, the treatment is either eye drops or laser therapy. Surgery for glaucoma is done after first trying drops and laser therapy. As mentioned earlier, in order to treat a cataract, a person must have cataract surgery. Currently, there are no drops or lasers that can cure a cataract.
The best way to evaluate if you have cataracts or glaucoma is to see an ophthalmologist. While cataracts may cause visual symptoms, glaucoma usually does not cause any symptoms at all until it is at an advanced stage. Seeing an in-person ophthalmologist at regular intervals is the best way to check for any eye diseases and address any sight-threatening issues in a timely fashion.