Cataract

Overview

A cataract is a condition where the natural lens of the eye becomes cloudy, leading to vision problems. People with cataracts often describe their vision as similar to looking through a frosted or fogged-up window. This clouded vision can make it difficult to read, drive, especially at night, and recognize facial expressions.

In the beginning, using brighter lights and wearing glasses can help with cataract-related vision problems. However, if your impaired vision starts to interfere with your daily activities, you might need cataract surgery, which is done by an eye specialist called an Ophthalmologist. It is generally considered a safe and effective procedure to improve vision and quality of life.

Symptoms

Cataracts often present with the following signs and symptoms:

• Vision becoming cloudy, blurred, or dim.
• Difficulty seeing clearly at night.
• Increased sensitivity to bright sunlight, headlights, or lamps.
• Requiring brighter lighting for reading and other activities.
• Noticing “halos” around lights.
• Needing frequent adjustments to eyeglass or contact lens prescription.
• Perceiving changes in the way colors appear, such as faded or less vivid colors.
• Experiencing double vision in one eye.

The initial stages of a cataract may cause minor cloudiness in the lens, potentially going unnoticed with no significant vision loss. However, as the cataract enlarges, it progressively clouds more of the lens and distorts light, resulting in more apparent symptoms. If you observe any changes in your vision, it is essential to schedule an eye exam. Additionally, if you experience sudden vision changes like double vision, flashes of light, sudden eye pain, or headaches, seek immediate medical attention from your doctor.

Causes

Cataracts mainly occur due to the gradual deterioration of proteins in the eye’s lens. Factors like aging or injury can lead to changes in the lens tissue, causing proteins and fibers to break down. This breakdown results in hazy or cloudy vision. Additionally, certain genetic disorders can increase the risk of cataracts, as well as other eye conditions, past eye surgeries, medical conditions like diabetes, and prolonged use of steroid medications.

A cataract is like a cloudy cover that forms over the lens of your eye, which is located behind the colored part called the iris. The lens normally helps focus light on the retina, which acts like the film in a camera and helps you see clear images. However, as you get older, the lens becomes less flexible, less transparent, and thicker. This aging process, along with certain medical conditions, causes proteins and fibers in the lens to clump together and form a cloud, making it difficult for light to pass through. This cloudiness scatters and blocks the light, leading to blurry vision.

Cataracts usually develop in both eyes, but they might not progress at the same speed. One eye may have a more advanced cataract than the other, causing differences in vision between the two eyes. As the cataract becomes denser over time, the blurriness in vision increases, making it harder to see clearly.

Types of cataracts

There are different types of cataracts, which include:

• Nuclear Cataracts: These cataracts affect the center of the lens, causing an initial increase in nearsightedness or a temporary improvement in reading vision. As time progresses, the lens turns progressively denser, taking on a yellow or even brownish hue, which clouds the vision. This advanced discoloration may lead to difficulties in distinguishing between shades of colors.
• Cortical Cataracts: In this type, opacities or streaks form at the outer edge of the lens cortex, appearing whitish and wedge-shaped. Gradually, these streaks spread toward the center of the lens, interfering with the passage of light through it.
• Posterior Subcapsular Cataracts: Beginning as small, opaque areas near the back of the lens, these cataracts obstruct the path of light. They often cause issues with reading vision, reduce vision in bright light, and create glare or halos around lights, particularly at night. Compared to other types, posterior subcapsular cataracts tend to progress more rapidly.
• Congenital Cataracts: Some people are born with cataracts or develop them during childhood. These cataracts can be genetic or associated with intrauterine infections or trauma. They may also be linked to certain conditions such as myotonic dystrophy, galactosemia, neurofibromatosis type 2, or rubella. While congenital cataracts don’t always affect vision, if they do, they are usually removed shortly after detection.

Risk factors

The following factors raise your chance of cataracts:

• Prolonged sun exposure
• Diabetes
• Smoking
• Old age
• Being overweight or obese
• Elevated blood pressure
• Excessive corticosteroid medication
• Overconsumption of alcohol
• A history of inflammation or damage or surgery to the eye