Overview

Cataracts is a condition affecting the lens of the eye and affects vision. The eye lens is made up of structural proteins called crystallins which helps with the transparency and focus. The light passes through the pupil and reaches the lens which converts light into nerve signals in the brain and allows the image to be visualised. As a person ages, the proteins in the lens break down which can impair vision.¹

Glaucoma is an eye condition which is caused by a group of eye disorders that damage the optic nerve,leading to loss of vision. The optic nerve is situated at the back of the eye where the nerve fibres send visual messages to the brain.^2,4

Cataract and glaucoma are more commonly seen in the elderly and are treated according to the symptoms and severity of each condition.³

Cataracts

Cataracts is an eye condition where cloudy patches form on the lens and makes vision difficult. As a person ages the proteins in the lens break down and affect the vision. Cataracts make the vision foggy, difficulty in reading and the person develops sensitivity to light.¹

Types

There are several types of cataracts and they are : 

• Congenital cataracts: This cataract is present when the child is born and mostly does not develop until they become older. Congenital cataract is mostly caused by genetic abnormality (passed down from a parent having cataract). This can also be caused when a mother is affected by infections during pregnancy⁵
• Nuclear cataracts: This is the cataract affecting the centre of the lens which causes distant vision difficult (myopia) and makes them blurry and easy to see the things near. As disease progresses the colour of the lens changes into yellow or brown, which makes the vision even worse
• Posterior subcapsular cataracts: This type of cataract affects the back of the lens as a small spot in the path of the light. This causes difficulty in reading, blurred vision around the lights and difficulty to see in bright light. This type of cataract tends to spread faster than the others⁶
• Cortical cataracts: This type of cataract affects the edges of the lens. A white wedge shaped spot or streaks slowly grows from the edges of the lens and spreads to the centre of the lens. This affects the person's vision⁷

Causes

Most common cause of cataract is ageing, but some other factors like certain medical conditions and lifestyle can increase the risk of getting cataract. 

• Age: Most common cause of cataract is the breakdown of the proteins in the lens and this happens as the person grows older. The vision becomes foggy or cloudy making it difficult for the person to read or see the image
• Trauma: This type of cataract is formed when there is an injury to the eye. Injury can also happen during any surgical procedure to the eye
• Genetic: In some cases childrens are born with cataract or develop cataract during their childhood. This condition occurs when there is genetic abnormality as it is passed down from one or both the parents affected by cataract. It can also be caused when a mother is affected by certain infections during pregnancy

Symptoms

Symptoms occurs according to the severity and the type of cataract and some of them are :

• Blurred or cloudy vision
• Difficulty in reading
• Light sensitivity
• Difficulty in seeing in bright light
• Difficulty in recognising colours
• Difficulty in seeing at night

Glaucoma

Glaucoma is a condition that damages the optic nerve causing vision problems. Mostly high eye pressure causes optic nerve damage, however, people without high eye pressure can also be affected by glaucoma. The back of the eyes is filled with fluid called vitreous humour which is a gel-like material and the front of the eyes is filled with aqueous humour, in between the cornea and the iris, which is more waterier. Eye pressure is measured by measuring the aqueous humour.^2,8

Types

1. Open angle glaucoma: The drainage canal is formed by iris and cornea which may function normally. But over months there may be fluid buildup due to the drainage canal having a block and this may cause increased pressure on the optic nerve⁹
2. Closed angle glaucoma: This occurs when the iris is bulged completely or partially. Formation of block in drainage canal prevents aqueous fluid leaving the eye and causes increases in eye pressure¹⁰
3. Normal tension glaucoma: In this type the optic nerve is damaged when the eye pressure is normal. This type is called normal pressure or low tension glaucoma¹¹
4. Congenital glaucoma: Childrens born with glaucoma or develop symptoms of glaucoma in the first few years of life¹²

Causes

Glaucoma occurs when a person has optic nerve damage. The most common cause of the nerve damage is due to the increased eye pressure, but in some cases glaucoma can also occur without increase in eye pressure. 

Symptoms

Symptoms vary according to the severity and the type and include: 

• Severe headache
• Eye pain
• Blurred vision
• Nausea and vomiting
• Coloured rings or halos around the lights
• Redness of the eye

Diagnosis

• Visual acuity test: This test helps to check whether the person is having vision problems. During this test the healthcare provider places a chart with alphabets or numbers or with both to test the vision. If the person is having difficulty in reading the doctor may prescribe glasses or contact lenses¹³
• Gonioscopy: An ophthalmologist examines the eye by using special lenses to check the drainage angle situated between the iris and cornea so see whether they are narrow or blocked. This helps in diagnosing glaucoma
• Slit lamp examination: In this test a bright light is used to see the structures and layers of the eyes which help the doctor to diagnose if any disease is present¹⁴
• Retinal examination : During this examination the doctor or the healthcare provider puts drops of medicine in the eyes of the person, which widens the pupil and makes it easy to examine the lens
• Eye fluid pressure test: A device called tonometry that helps in measuring the intraocular pressure (IOP) of the eyes. Eyes are filled with fluid, the back of the eyes is filled with fluid called vitreous humour which is a gel like material and the front of the eyes is filled with aqueous humour in between the cornea and the iris which is more waterier. Eye pressure is measured by measuring the aqueous humour
• Visual field test: A simple non-invasive test, where they examine the person’s peripheral vision

Management and treatment

• Managing cataract symptoms while living with glaucoma is taking care of both the conditions simultaneously. As both the disease condition mostly affects the old age people and causes vision loss or impairment they may co-exist³
• When a person is affected with cataract they will be having vision problems mostly in the early stage but in case of glaucoma the symptoms appear in its advanced stage
• Medications for glaucoma can worsen the symptoms of cataract by increasing the vision problems. Eye drops like propine and epinephrine dilate the pupil which increases the glared vision
• If a person is having cataract then it is important to examine any optic nerve damage so that glaucoma can be found sooner
• Surgery is the best option for cataract treatment.  In cases of poorly treated glaucoma, cataract surgery can increase the intraocular pressure. In cases where glaucoma is well treated with medicine the patient can go with cataract surgery
• Combined cataract and glaucoma surgery is considered in patients with more severe conditions. Combined surgery helps in reducing the intraocular pressure and decreased medications after surgery³

FAQs

Is it safe to have cataract surgery if you have glaucoma?

Generally cataract surgery is considered safe while diagnosed with glaucoma as it reduces the intraocular pressure.

How to treat cataract and glaucoma?

Cataracts can be treated with the help of surgery. Glaucoma is treated with the help of laser treatment or surgery where it reduces the eye pressure and reduces the vision loss. But no treatment can restore the lost vision incase of glaucoma.

How long is the recovery time taken for the combined cataract and glaucoma surgery?

Recovery time taken after the surgery is about 1 week, after which the patient can go into their daily routine.

Summary

Managing cataract symptoms while living with glaucoma is taking care of both conditions simultaneously. Both conditions mostly affect the elderly and cause vision loss or impairment, and therefore may co-exist. Medications for glaucoma can worsen the symptoms of cataract by increasing the vision problems. 

If a person has cataracts, it is important to examine for optic nerve damage so that glaucoma can be found sooner. Surgery is the best option for cataract treatment. In case of poorly treated glaucoma, cataract surgery can increase the intraocular pressure. In cases where glaucoma is well treated with medicine the patient can go with cataract surgery. Combined cataract and glaucoma surgery is considered in patients with more severe conditions. Combined surgery helps in reducing the intraocular pressure and decreased medications after surgery.