What Is Cataract Surgery?

  • Hima SaxenaMasters in Pharmacy - M.Pharm, Uttarakhand Technical University, India
  • Muna Hassan Bachelor of science in molecular biology and Genetics (2023)


Cataract surgery is a medical procedure aimed at treating the clouding of the eye's natural lens, known as a cataract, which can lead to impaired vision and visual discomfort.1 The lens of the eye is normally clear, but as we age or due to conditions such as diabetes, trauma or steroid medication, the lens can become cloudy, causing vision to become blurry and sensitive to glare. Cataracts are a common age-related condition, and their development is often a natural part of the ageing process.2

Cataract surgery involves the removal of the cloudy lens and its replacement with an artificial intraocular lens (IOL) to restore clear vision. This surgical procedure has evolved significantly, becoming one of the most common and successful surgeries worldwide. Advances in surgical techniques, equipment, and intraocular lens technology have contributed to improved outcomes and reduced recovery times.1

In this article, we will delve into the causes and symptoms of cataracts, the types of cataract surgery, the cataract surgery process and the risks and complications associated with the procedure.

Causes of cataracts

Cataracts are caused by changes in the structure of the lens in the eye. These changes occur when the protein in the lens undergoes a natural deterioration process.

The factors that can contribute in the development of cataracts include:

  • Family history of cataracts
  • Medical conditions such as diabetes
  • Eye injury
  • Eye surgery to treat glaucoma
  • Eye conditions such as retinitis pigmentosa or uveitis
  • Medications such as steroids used to treat arthritis
  • Radiation treatment in the upper body for the treatment of diseases such as cancer
  • Smoking
  • Chronic alcohol consumption
  • Prolonged sun exposure without sunglasses

Who needs cataract surgery?

Cataracts do not require immediate medical attention typically, so if you have recently been diagnosed with them, you can decide if you want to have the surgery or schedule it according to your preference. 

However, your eye specialist may suggest cataract surgery to see the back of the eye to manage medical conditions such as age-related macular degeneration or diabetes-related retinopathy to prevent loss.

Initially, you may observe symptoms of cataracts which include:

  • Your vision is cloudy, blurry, foggy or filmy
  • Alterations in colour perception, with colours appearing faded 
  • Increased sensitivity to bright sunlight or headlights
  • Glare issues, including the presence of halos or streaks around light sources
  • Challenges in nighttime visibility
  • Adjustments in prescription for glasses
  • Occurrence of double vision

These symptoms can be managed by getting a new eyeglass or contact lens prescription. However, cataracts tend to progress over time. When they start hindering your ability to perform essential tasks or daily activities, that's when surgery may become necessary. It's advisable to discuss with your eye surgeon to determine the most suitable timing for surgery based on your specific circumstances.1

Intraocular lens (IOL) implants

Intraocular lens implants are artificial lenses for the eyes made from plastic, acrylic or silicone material. They are used to replace the eye's natural lens, which becomes cloudy due to cataracts or correct refractive errors like nearsightedness or farsightedness. They can help restore clear vision, reduce dependence on glasses, and improve the overall quality of life for people undergoing cataract surgery or refractive lens exchange.3

There can be various types of IOL3

Type of IOLPurposeCommon usage
Monofocal IOLsProvide clear vision at a single focal point (distance or near).Commonly used in cataract surgery. Suitable for individuals with specific visual requirements, but glasses may still be needed for some tasks.
Multifocal IOLsProvide clear vision at multiple distances (near, intermediate, distance).Chosen by those wanting reduced dependence on glasses for various activities. Some may experience halos or glare, especially in low light.
Accommodative IOLsMimic the natural lens's ability to shift focus, providing clear vision at different distances.Intended to reduce dependence on glasses for a range of distances, offering a more natural and continuous visual experience.
Toric IOLsSpecifically designed to correct astigmatism.Recommended for individuals with cataracts and astigmatism. Improve visual outcomes and reduce the need for glasses, especially for distance.

Types of cataract surgery

The choice of cataract surgery technique depends on various factors, including the patient's eye health, the severity of the cataract, and the surgeon's expertise. The types of cataract surgery techniques include:


Phacoemulsification is the most common and widely used cataract surgery technique. In this procedure, a small incision (usually less than 3 mm) is made in the cornea. A probe is inserted through the incision, which emits ultrasound waves to break up the cloudy lens into small fragments. The fragmented lens is then suctioned out of the eye. An intraocular lens (IOL) is usually inserted to replace the natural lens.4

Extracapsular cataract extraction (ECCE)

ECCE technique involves a larger incision (around 10-12 mm) in the upper section of the eye.1 The entire cloudy lens is removed in one piece, leaving the back part of the lens capsule intact. The remaining cataract material is removed via suction through the incision. 

There are variations and advancements within these main types of cataract surgery, such as–

Laser-assisted cataract surgery (LACS)

This involves using a laser to perform some of the steps in cataract surgery, such as creating incisions or softening the cataract for easier removal. It may be used in combination with phacoemulsification.5

Femtosecond laser-assisted cataract surgery (FLACS)

Femtosecond laser-assisted cataract surgery (FLACS) is an advanced surgical technique that employs a femtosecond laser to enhance the precision and efficiency of cataract removal. During FLACS, the laser is used for creating corneal incisions, capsulotomy (opening in the lens capsule), and fragmenting the cataract. This technology allows for customizable incisions and precise capsular openings, potentially reducing surgical complications.6 

Cataract surgery procedure

Cataract surgery involves removing the cloudy lens and replacing it with an artificial intraocular lens (IOL). If you have cataracts in both eyes, a surgery known as immediate sequential bilateral cataract surgery (ISBCS), may be recommended for treating both eyes on the same day. This is suitable for people who have a low risk of complications, and your eye specialist will discuss this option with you based on your situation.

Here is an overview of the cataract surgery process:

Before the surgery

Before surgery, your eye specialist will take the following steps to get you ready for the surgery:

  • A week before the surgery, the eye specialist will perform some tests to measure the size and shape of your eyes to choose the right type of intraocular lens suitable for you.
  • Your eye specialist may prescribe eye drops to prevent eye infections.
  • If you are taking a medication that may lead to bleeding during your surgery, your eye specialist might request you to temporarily discontinue its use.
  • You may be asked to not eat or drink several hours before the surgery.

During the surgery

The following steps are carried out during the cataract surgery procedure:

  • Before the surgery, eye drops or an injection around the eye will be used to numb the eye.
  • The surgeon makes tiny incisions near the cornea's edge to reach the lens, using small instruments to break up and remove the cataract. The new lens is then inserted into place.
  • In some cases, a small stitch may be used to close the incision. However, many modern cataract surgeries use self-sealing incisions that do not require stitches. 
  • The recovery period is usually short. You may be monitored for a brief period after the surgery and can go home on the same day.

After the surgery

After the surgery, the sensation in your eye will gradually reappear, yet complete restoration of your vision may require a few days.

  • The eye specialist will give you eye drops to prevent infection and reduce swelling. You may need to wear a special eye shield or glasses. 
  • You may experience side effects such as watering, and blurred or double vision which may improve within a few days but may require 4 to 6 weeks in a few cases.

Do’s and don’ts after surgery

During the initial weeks after the surgery follow these steps:

  • Follow the prescribed instructions for using eye drops
  • Use your eye shield at night for a minimum of one week
  • Bathe or shower as usual
  • Utilize your shield, previous glasses, or sunglasses when outdoors
  • Avoid swimming for a period of 4 to 6 weeks
  • Refrain from rubbing your eyes
  • Prevent soap or shampoo from entering your eyes
  • Do not drive until you have consulted with your doctor
  • Avoid strenuous exercise or housework
  • Seek advice from your doctor before flying

Benefits of cataract surgery

The benefits of cataract surgery include:

  • Improved vision
  • Reduced glare
  • Reduced dependency on glasses
  • Experience more vibrant colours

Risks of cataract surgery

The risks associated with cataract surgery include:

  • Infection
  • Bleeding
  • Swelling
  • Eye pain
  • Vision loss
  • IOL displacement (artificial lens moves out of place)
  • Posterior capsular opacification or secondary cataract (lens capsule becomes cloudy)
  • Seeing halos, glare, and dark shadows
  • Blurred vision
  • Retinal detachment the thin layer at the back of the eye becomes loose)


How painful is cataract surgery?

Cataract surgery is typically not painful due to local anaesthesia. Patients may feel slight pressure or discomfort, but pain is minimal. Advances like phacoemulsification ensure smaller incisions, reducing postoperative discomfort. Most people experience improved vision and minimal discomfort during recovery, making cataract surgery generally well-tolerated.

Which surgery is best for cataracts?

Phacoemulsification is the most common and preferred surgery for cataracts. This minimally invasive procedure involves using ultrasound to break up and remove the cloudy lens. It requires a small incision, promotes faster healing, and often allows for a quicker return to normal activities compared to other surgical techniques.

What are the most common problems after cataract surgery?

Common post-cataract surgery issues include temporary blurred vision, dry eyes, and sensitivity to light. In rare cases, complications like infection, inflammation, or posterior capsule opacification may occur. Promptly reporting any persistent or severe symptoms to the eye surgeon ensures timely intervention for the successful resolution of these issues.


Cataract surgery is a medical procedure designed to address cataracts, which cause vision impairment due to clouding of the eye's lens. This surgery involves the removal of the cloudy natural lens and its replacement with an artificial intraocular lens (IOL) to restore clear vision. Preceding the surgery, patients undergo a comprehensive eye examination to determine the severity of the cataract and establish an appropriate treatment plan. Local anaesthesia ensures patient comfort during the procedure, and laser technology may be employed in certain cases. Recovery is typically swift, with improved vision manifesting within days to weeks. Postoperative care includes prescription eye drops and a brief period of activity restriction. Cataract surgery is considered one of the most effective and routine surgical interventions in modern medicine. It has significantly improved the quality of life for millions of people worldwide by restoring clear vision and reducing the impact of cataracts on daily activities.


  1. Moshirfar M, Milner D, Patel BC. Cataract Surgery. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 [cited 2023 Dec 3]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK559253/.
  2. Nizami AA, Gulani AC. Cataract. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 [cited 2023 Dec 3]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK539699/.
  3. Lapp T, Wacker K, Heinz C, Maier P, Eberwein P, Reinhard T. Cataract Surgery—Indications, Techniques, and Intraocular Lens Selection. Dtsch Arztebl Int [Internet]. 2023 [cited 2023 Dec 4]; 120(21–22):377–86. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10413970/.
  4. Benítez Martínez M, Baeza Moyano D, González-Lezcano RA. Phacoemulsification: Proposals for Improvement in Its Application. Healthcare (Basel) [Internet]. 2021 [cited 2023 Dec 4]; 9(11):1603. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8621996/.
  5. Day AC, Gore DM, Bunce C, Evans JR. Laser‐assisted cataract surgery versus standard ultrasound phacoemulsification cataract surgery. Cochrane Database Syst Rev [Internet]. 2016 [cited 2023 Dec 4]; 2016(7):CD010735. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6458014/.
  6. Sun H, Fritz A, Dröge G, Neuhann T, Bille JF. Femtosecond-Laser-Assisted Cataract Surgery (FLACS). In: Bille JF, editor. High Resolution Imaging in Microscopy and Ophthalmology: New Frontiers in Biomedical Optics [Internet]. Cham: Springer International Publishing; 2019 [cited 2023 Dec 4]; p. 301–17. Available from: https://doi.org/10.1007/978-3-030-16638-0_14.
This content is purely informational and isn’t medical guidance. It shouldn’t replace professional medical counsel. Always consult your physician regarding treatment risks and benefits. See our editorial standards for more details.

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Hima Saxena

Masters in Pharmacy - M.Pharm, Uttarakhand Technical University, India

Hima Saxena is a dedicated professional with a Master's degree in Pharmacy, who possesses a profound passion for medical science and its effective communication. Her articles adeptly blend pharmaceutical knowledge with writing skills, ensuring readers gain a comprehensive understanding of crucial medical topics. Her experience in writing and editing further strengthens her commitment to providing informative, precise, and easily accessible information. Hima is eager to leverage her knowledge and communication skills to enhance health awareness and knowledge through her writing.

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