Glaucoma and Cataract are eye disorders posing risk to vision loss if not diagnosed and treated on time. However, there are marked differences between glaucoma and cataract. The vision loss due to glaucoma is considered to be irreversible while the vision loss due to cataract is reversible in almost all cases.
Cataract progresses gradually and painlessly, resulting in a loss of transparency in the eye's lens, obstructing proper light entry leading to gradual vision loss. On the other hand, glaucoma can sometimes manifest as a rapid and painful condition but most of the times it is subtle and progresses slowly. Glaucoma is caused by high pressure in the eye which damages the optic nerve. The optic nerve plays a crucial role in processing visual information sent to the brain from the eye. While cataract are less likely to cause blindness, glaucoma can lead to irreversible blindness and requires immediate treatment.
In this article, we will look at all the details about glaucoma and cataract differences, who are more susceptible to these conditions and what treatments patients of either of these conditions must look for to get better.
Difference Between Glaucoma and Cataract
Glaucoma and Cataract are both eye disorders that can result in vision loss and impact overall eye health. While they may share some similar symptoms and risk factors, they are distinct conditions with different causes, treatments, and potential outcomes. Let's look at the differences between glaucoma & cataract in detail.
What is Glaucoma?
Glaucoma refers to an eye disorder that damages the optic nerve. It typically occurs when an accumulation of a fluid called aqueous humor within the eye leads to elevated intraocular pressure (IOP). This increase in eye pressure can result from excessive aqueous humor production or blockages in the drainage pathways, specifically the trabecular meshwork. The heightened IOP can cause damage to the optic nerve, ultimately leading to the development of glaucoma.
Glaucoma can be of two types:
Primary open-angle glaucoma: This is the most prevalent type of glaucoma. It is characterized by increased resistance to drainage of aqueous humor in the trabecular meshwork, even though the drainage angle between the cornea and the iris remains open resulting in an accumulation of intraocular pressure that harms the optic nerve. Despite being painless and not causing immediate changes in vision, primary open-angle glaucoma can progress unnoticed. Hence, routine eye examinations are essential to detect early signs of optic nerve damage. While there are typically no noticeable symptoms in the early stages of primary open-angle glaucoma, in advanced stages, you may begin to observe blind spots or patches in your peripheral (side) or central vision, which can affect one or both eyes and tunnel vision, where your field of vision narrows significantly.
Angle-closure glaucoma: Angle-closure glaucoma occurs when an individual's iris is positioned very closely to the eye's drainage angle, obstructing the fluid drainage mechanism. The drainage angle is responsible for fluid drainage and maintaining normal intraocular pressure. The closure of this space can occur gradually or suddenly. People with a gradual onset of angle-closure glaucoma may not experience noticeable symptoms. However, in cases where eye fluid suddenly becomes unable to pass through the drainage angle, eye pressure rises sharply resulting in significant pain & posing a significant risk of blindness. If this acute condition occurs, immediate consultation with an ophthalmologist is imperative. Individuals of Asian descent and those with farsightedness(Hypermetropia) are at a higher risk of developing this type of glaucoma.
Glaucoma – Who is at risk?
Individuals aged 60 and older typically face an elevated risk of developing glaucoma. Additionally, having a first-degree family member with glaucoma increases the likelihood of developing the condition.
What is a Cataract?
Cataract is more of an age related condition, though there could be other predisposing factors. They can also result from eye injuries or as a complication following surgery for other eye conditions, such as glaucoma, retinal surgeries etc. People develop cataract when the crystalline lens inside the eye becomes clouded due to the denaturation of proteins. This lens plays a crucial role in allowing light to enter the eye and focus images on the retina at the back of the eye.
Initially, vision loss may not be readily noticeable, but as cataract progress, individuals may experience symptoms such as blurred vision, glare, and increased difficulty seeing clearly up close or in low-light conditions. cataract can also interfere with everyday activities like reading. While cataract typically develop as a natural part of ageing.
Cataract – Who is at risk?
Cataract can develop for various reasons, with some individuals being born with them due to prenatal infections and rare cases of cataract occurring during childhood. Additionally, cataract may result from eye injuries or surgical procedures. However, the most prevalent cause of cataract is the natural ageing process, leading to eye changes. Approximately 2.5% of individuals have cataract around the age of 40, but this prevalence increases significantly to about 49% by the age of 75.
Several other factors can also heighten the risk of cataract development, including conditions such as diabetes, obesity, and high blood pressure. Lifestyle choices like smoking, excessive alcohol consumption, prolonged use of steroids, and sun exposure can cause cataract.
Symptoms: Glaucoma vs Cataract
The symptoms of glaucoma and cataract might have some similarities. However, there are marked differences as well, just like there are differences between glaucoma and cataract.
Glaucoma symptoms may include:
Ocular discomfort or eye pain
Vision becomes blurred
The eye may appear red
Perceiving halos around lights
Experiencing bouts of vomiting or nausea
Suffering from severe headaches sometimes
Vision seeming to be blocked at the sides
Blind spots can occur in central or peripheral vision and are frequently observed in both eyes
Tunnel vision
The symptoms of cataract may include:
Difficulty seeing in low light or night blindness
Perceiving colors as faded or less vibrant
Experiencing double vision
Frequent adjustments required for your eyeglasses prescription
Vision appears cloudy or blurry
Sensitivity to light sources like headlights, lamps, and sunlight, causing discomfort
Diagnosis and Treatment – Glaucoma
Glaucoma can be detected through a standard eye examination. During the diagnostic process, your doctor will assess the pressure within your eye, a painless procedure. Thereafter your pupil will be dilated by administering eye drops to examine the optic nerve and retina thoroughly. If needed, your eye may also be subjected to various investigations and scans like perimetry(Visual field test), OCT(Optical Coherence Tomography), Pachymetry(Corneal thickness test), Gonioscopy etc may be advised to detect signs of glaucoma.
The primary treatment for glaucoma typically involves medicated eye drops, which aim to reduce intraocular pressure. If eye drops are not suitable or prove ineffective, your ophthalmologist may recommend laser surgery or Trabeculectomy to facilitate proper eye fluid drainage. In some instances, surgical or microsurgical techniques may be required to create small openings that enable fluid drainage, or tiny tubes or stents may be inserted into your eye to facilitate fluid outflow. During these procedures, you will remain awake but receive numbing and sedation to ensure your comfort.
Diagnosis and Treatment – Cataract
Cataract can be identified through a standard eye examination. Your physician will administer eye drops to temporarily enlarge (dilate) your pupil, enhancing their ability to detect any cataract present on your lens.
Various options are available depending on the stage and density of your cataract. If the cataract is mild a spectacle prescription adjustment may suffice to address changes in your vision. However, surgical intervention may be necessary if your cataract have advanced significantly. Cataract surgery is a frequently performed procedure known for its generally positive outcomes.
Conclusion
Glaucoma and Cataract pose risks of vision loss if not promptly diagnosed and treated. These conditions can lead to symptoms like blurry vision and other visual disturbances. Glaucoma arises due to an accumulation of eye fluid, resulting in increased pressure on the optic nerve, potentially leading to permanent vision loss. Treatment primarily targets reducing intraocular fluid pressure.
Cataract, on the other hand, stem from the denaturation of protein in the eye's lens, resulting in symptoms such as cloudy vision, double vision, and difficulty seeing in low-light conditions. Age increases the likelihood of cataract development, but fortunately, cataract surgery can effectively restore vision in most cases. Regular eye examinations are essential, particularly as you age, to ensure early detection of glaucoma or cataract and to maintain healthy eyes and clear vision.
Read more about the author
Medical Director & Senior Eye Surgeon
One of the best Cataract, Cornea and Lasik eye surgeons in Gurgaon.
Exp: 20 Yrs
Visit the LinkedIn profile