Cataracts

When the lens becomes cloudy, light cannot pass through or focus properly. This may cause blurred, hazy, or misty vision. Cataracts most commonly develop as part of the ageing process, with changes in the lens often beginning from middle age onwards.

What Is the Natural Lens of the Eye?

The natural lens is a clear, curved structure located behind the iris.

It works together with the cornea to bend incoming light and focus it onto the retina, making vision possible. The lens can also adjust its focusing power to help the eye see objects at different distances.

Because of its important function, the lens is located near the centre of the eye, where it is relatively well protected from external injury.

Factors That May Accelerate Cataract Development

Although ageing is the most common cause, cataracts may develop earlier because of other factors, including:

๐ Long-term use of corticosteroid medicines

๐ Diabetes

๐ Eye injuries

๐ Certain eye diseases

๐ Prolonged exposure to ultraviolet radiation without suitable eye protection

๐ Congenital abnormalities

๐ Maternal infections during pregnancy, such as rubella

Symptoms of Cataracts

Cataracts usually develop gradually over months or years and do not normally cause eye pain or redness.

Gradually Blurred Vision

Patients may notice that their vision becomes increasingly cloudy, as though looking through fogged glass.

In the early stages, some people may see better in dim conditions than in bright light. This can occur when cloudiness is concentrated in the centre of the lens.

In low light, the pupil becomes larger, allowing light to pass through the clearer outer part of the lens. In bright light, the pupil becomes smaller, directing more light through the cloudy central area and making vision appear worse.

Glare and Sensitivity to Light

Common symptoms include:

๐ Difficulty looking at bright lights

๐ Glare from sunlight or vehicle headlights

๐ Halos around lights

๐ Difficulty driving at night

๐ Reduced contrast between objects and their surroundings

Double or Multiple Images

Some patients may see two or more images even when looking with only one eye.

This occurs because the cloudy lens bends light unevenly, preventing it from focusing at a single point on the retina.

Changes in Colour Vision

Colours may appear:

๐ Faded

๐ Less vivid

๐ More yellow or brown than usual

Frequent Changes in Glasses

Patients may need to change their glasses prescription more frequently because the cataract alters the focusing power of the lens.

Temporary Improvement in Near Vision

Some older adults may suddenly find that they can read without their usual reading glasses.

This does not necessarily mean that their eyesight has genuinely improved. It may be an early sign of cataract-related changes in the lens, sometimes described as a temporary “second sight”.

Do Cataracts Affect Both Eyes?

Age-related cataracts commonly develop in both eyes, but they may not progress at the same speed.

One eye may become significantly cloudier before the other, resulting in unequal vision between the two eyes.

If the lens becomes completely cloudy, vision may become severely impaired. The speed of progression differs between individuals.

Cataract Treatment

The definitive treatment for cataracts is surgery.

During cataract surgery, the ophthalmologist removes the cloudy natural lens and replaces it with an artificial intraocular lens.

Surgery is generally considered when the cataract interferes with daily activities such as:

๐ Reading

๐ Driving

๐ Working

๐ Watching television

๐ Walking safely

๐ Recognising faces

Cataract Surgery Methods

Phacoemulsification

Phacoemulsification is the most commonly used cataract surgery technique.

The procedure generally involves:

๐ Applying anaesthetic eye drops or giving a local anaesthetic injection

๐ Making a small incision of approximately 2–3 millimetres near the edge of the cornea

๐ Inserting a small ultrasound instrument into the eye

๐ Breaking the cloudy lens into tiny fragments

๐ Suctioning the fragments from the eye

๐ Inserting an artificial intraocular lens into the remaining lens capsule

Because the incision is small, stitches are often unnecessary.

Extracapsular Cataract Extraction

Extracapsular cataract extraction may be used when the cataract is too dense or unsuitable for phacoemulsification.

During this procedure, the cloudy lens is removed while the back portion of the lens capsule is preserved to support the artificial lens.

This technique requires a larger incision and usually involves stitches.

Anaesthesia for Cataract Surgery

Different forms of anaesthesia may be used depending on the surgical method and the patient’s condition.

Anaesthetic Eye Drops

Eye-drop anaesthesia is commonly used for phacoemulsification.

The patient remains awake but should not feel significant pain during the operation.

Local Anaesthetic Injection

An anaesthetic injection around the eye may be used for:

๐ Extracapsular cataract extraction

๐ Selected phacoemulsification cases

๐ Patients who need better control of eye movement during surgery

General Anaesthesia

General anaesthesia may be considered when the patient cannot safely or comfortably undergo surgery using local anaesthesia.

The ophthalmologist and anaesthetist will select the most appropriate method.

Artificial Intraocular Lenses

After the cloudy natural lens has been removed, the ophthalmologist inserts an artificial intraocular lens to restore the eye’s focusing ability.

Different types of intraocular lenses are available.

The choice depends on:

๐ The patient’s daily visual needs

๐ Eye health

๐ Corneal condition

๐ Retinal condition

๐ The presence of astigmatism

๐ The patient’s expectations

๐ The advantages and limitations of each lens type

The ophthalmologist and patient should discuss the available options before surgery.

Care After Cataract Surgery

Immediately After Surgery

The operated eye is usually covered with a protective shield or dressing.

The following day, the patient may return for:

๐ Removal of the eye covering

๐ Vision assessment

๐ Examination by the ophthalmologist

๐ Instructions on cleaning the eye

๐ Guidance on using prescribed eye drops

Medication

๐ Use all eye drops and medicines exactly as prescribed.

๐ Do not use preoperative eye drops after surgery unless instructed by the ophthalmologist.

๐ Resume medicines that were stopped before surgery only when advised by the doctor.

Follow-Up Appointments

Follow-up examinations may be scheduled approximately:

๐ One week after surgery

๐ One month after surgery

๐ Three months after surgery

The schedule may vary depending on the patient’s recovery and eye condition.

Protecting the Eye During the First Month

During the first month after surgery:

๐ Prevent water from entering the operated eye.

๐ Wipe the face gently instead of splashing water onto it.

๐ Ask another person to help wash the hair, or have it washed while wearing an eye shield.

๐ Avoid dust, strong wind, smoke, and other eye irritants.

๐ Do not rub or press the eye.

๐ Protect the eye from accidental impact.

๐ Wear an eye shield while sleeping if instructed.

๐ Avoid lifting heavy objects.

๐ Avoid strenuous exercise and activities requiring significant physical effort.

Cleaning Around the Eye

Clean the area around the operated eye at least once daily for approximately two to four weeks, or according to the ophthalmologist’s instructions.

Use clean materials and avoid touching the eye directly.

Using the Eyes After Surgery

Patients may generally use their eyes for normal activities, including reading or watching television.

However, they should rest if they experience:

๐ Eye fatigue

๐ Burning

๐ Dryness

๐ Discomfort

Warning Signs After Cataract Surgery

Patients should contact their ophthalmologist immediately if they experience:

๐ Increasing eye pain

๐ Sudden or worsening blurred vision

๐ Red or swollen eyelids

๐ Significant eye redness

๐ Unusual eye discharge

๐ Flashes of light or a sudden increase in floaters

๐ A dark curtain or shadow in the visual field

Early assessment is important because these symptoms may indicate an infection, inflammation, retinal problem, or another postoperative complication.

Summary

A cataract occurs when the natural lens of the eye becomes cloudy, preventing light from focusing clearly on the retina. Symptoms may include gradual blurred vision, glare, colour changes, double vision, and frequent changes in glasses.

Cataracts cannot be permanently cleared with medicine or eye drops. When vision begins to interfere with daily life, surgery to remove the cloudy lens and insert an artificial intraocular lens is the standard treatment.

 

Reference:

Bangphai Hospital Cataracts

ArokaGO Providers Bangphai Hospital