Surgery Overview
A
		  cataract is a painless, cloudy area in the lens of the
		  eye. The lens is enclosed in a lining called the lens capsule. Cataract surgery
		  separates the cataract from the lens capsule. In most cases, the lens will be
		  replaced with an intraocular lens implant (IOL). If an IOL cannot be used,
		  contact lenses or eyeglasses must be worn to compensate for the lack of a
		  natural lens.
Phacoemulsification and standard extracapsular cataract extraction (ECCE) are
		  surgical methods that remove the cataract as well as the front portion of the
		  lens capsule (anterior capsule). The back of the lens capsule (posterior
		  capsule) is left inside the eye to keep the
		  vitreous gel in the back of the eye from oozing
		  forward through the pupil and causing problems. The posterior capsule also
		  supports the IOL and helps keep it in the proper position. These types of
		  surgery are usually done in an outpatient setting and not in a hospital.
 Phacoemulsification  (small-incision surgery) is the most common type of cataract
		  surgery. It is used more often than standard ECCE, even though
		  they are similar procedures. 
During phacoemulsification surgery:
- Two small incisions are made in the eye where the clear
			 front covering (cornea) meets the white of the eye (sclera).
- A
			 circular opening is created on the lens surface (capsule).
- A small
			 surgical instrument (phaco probe) is inserted into the eye.
- Sound
			 waves (ultrasound) are used to break the cataract into small pieces. Sometimes a laser is used too. The
			 cataract and lens pieces are removed from the eye using suction.
- An
			 intraocular lens implant (IOL) may then be placed inside the lens
			 capsule.
- Usually, the incisions seal themselves without stitches.
During standard ECCE:
- An 8 mm to
			 10 mm incision is made in the eye where the
			 clear front covering of the eye (cornea) meets the white of the eye (sclera).
			 
- Another small incision is made into the front portion of the lens
			 capsule. The lens is removed, along with any remaining lens
			 material.
- An IOL may then be placed
			 inside the lens capsule. And the incision is closed.
Children and infants
In some children, surgery to remove a cataract that causes
		  a lot of vision loss may be very important in preventing blindness. The most
		  critical period for the development of sight is from birth to 3 months. The
		  earlier cataracts in children are diagnosed and treated, the more likely it is
		  that their eyesight will be protected.
Anesthesia
Most cataract surgery is done using a topical anesthetic
			 (eyedrops) or a local anesthetic. Local anesthetic may involve a sedative for
			 relaxation followed by an injection beside, under, or inside the eye to deaden
			 nerves and prevent blinking or eye movement during surgery.
General anesthetic may be needed for:
- People with extreme anxiety that cannot be
				controlled with simple sedation or counseling.
- People who are
				unable to follow instructions during surgery.
- People who are
				allergic to certain local anesthetics.
- People with other medical
				conditions that require the use of a general
				anesthetic.
- Children.
What To Expect After Surgery
Before you leave the outpatient center, you will get the
		  immediate eye care that you need after surgery. The surgeon will review the
		  symptoms of possible complications, eye protection, activities, medicines, and
		  required visits (see below). He or she will also tell you what to do for emergency care if you need it.
		  Portions of the follow-up may be done by another health professional, such as
		  an optometrist or a community health nurse.
The eye that was operated on may be bandaged for 1 night after
		  surgery. You will wear a protective shield over the eye at night for about a
		  week. There is normally no significant pain after surgery.
You most likely will need to see the doctor for checkups 1 or 2
		  days after surgery, and again within a few weeks after surgery. If any complications occur, visits should be sooner
		  and more frequent.
Checkups following cataract surgery include:
- Ophthalmoscopy, to evaluate the inside of the
			 eye.
- Measurement of
			 visual acuity and eye pressure
			 (tonometry).
- A slit lamp exam, to check for lens clarity.
Most people get a new eyeglass prescription about 6 weeks after surgery.
Contact your doctor promptly if you notice any signs of
		  complications following cataract surgery, such as:
- Decreasing vision.
- Increasing
			 pain.
- Increasing redness.
- Swelling around the
			 eye.
- Discharge from the eye.
- New
			 floaters,
			 flashes of light, or changes in your field of
			 vision.
Why It Is Done
The decision to have this procedure is based on whether:
- Your work or lifestyle is affected by vision
			 problems caused by the cataract.
- Glare caused by bright lights is a
			 problem.
- You cannot pass a vision test required for a driver's
			 license.
- You have double vision.
- You notice a big difference in
			 vision when you compare one eye to the other.
- You have another
			 vision-threatening eye disease, such as
			 diabetic retinopathy or
			 macular degeneration.
The surgeon may need to do standard extracapsular cataract extraction (ECCE) instead of phacoemulsification if the cataract is too hard to be broken up by sound waves (ultrasound).
How Well It Works
Cataract surgery is successful for 85 to 92 out of 100 adults. Surgery may also improve vision in infants who have
		  cataracts. 
In one
		  large study, 95 out of 100 adults were satisfied with the results of their surgery.
		  The people who were not satisfied were older adults who had other eye problems
		  along with cataracts.footnote 1
 People who have surgery for cataracts usually have:
- Improved vision.
- Increased mobility
			 and independence.
- Relief from the fear of going blind.
Studies done with adults 1 year after surgery show that phacoemulsification works better than standard extracapsular cataract extraction (ECCE) to improve vision.footnote 2 Also, recovery of sight occurs sooner
		  after surgery with phacoemulsification. And it is less likely that you will
		  need glasses for distance vision after phacoemulsification surgery.
Risks
Fewer than 10 out of 100 people have complications from cataract surgery
		  that could threaten their sight or require further surgery.footnote 3 The rate of
		  complications increases in people who have other eye diseases in addition to
		  the cataract.
Although the risk is low, surgery for cataracts does involve the
		  risk of partial to total vision loss if the surgery is not successful or if
		  there are complications. Some complications can be treated and vision loss
		  reversed, but others cannot. Complications that may occur with
		  cataract surgery include:
- Infection in the eye
			 (endophthalmitis).
- Swelling and fluid in the center of the nerve
			 layer (cystoid macular edema).
- Swelling of the clear covering of
			 the eye (corneal edema).
- Bleeding in the front of the eye
			 (hyphema).
- Detachment of the nerve layer at the
			 back of the eye (retinal detachment).
Complications that may occur some time after surgery
		  include:
- Problems with glare.
- Dislocated
			 intraocular lens.
- Clouding of the portion of the lens covering
			 (capsule) that remains after surgery, often called aftercataract (posterior capsular opacification). This is usually not a
			 big problem and can be treated with laser surgery, if  
			 needed. The type of IOL may affect how likely it is to have clouding after surgery.
- Retinal detachment.
- Glaucoma.
- Astigmatism or
			 strabismus.
- Sagging of the upper eyelid
			 (ptosis).
What To Think About
Before you have surgery
		  for cataracts, tell your doctor  all of the medicines you are taking.
		  That way, your doctor can be prepared to handle any problems that arise. For example, alpha-blockers (such as tamsulosin or terazosin) and blood thinners can cause problems during the surgery.
Removing cataracts using phacoemulsification is preferred over
		  standard extracapsular surgery because:
- The surgery can be done more
			 quickly.
- There is less astigmatism after
			 surgery.
- Recovery of sight after surgery is faster.
- The
			 risk of complications after surgery is less.
 The improvement
		  of vision is the same for both procedures. But the healing process is quicker
		  for phacoemulsification.
The more experience your surgeon has, the less likely you are to have problems. Ask your  family doctor or optometrist to suggest a surgeon.
People usually need glasses after
		  cataract surgery, no matter which type of surgery is done. But the need for glasses and the type of glasses you need will depend on the type of  intraocular lens implant, or IOL, that you choose. Talk to your doctor about the pros and cons of each type of IOL.
 If you have an astigmatism, your surgery may cost more. Talk to your doctor about your treatment options and costs.
Complete the surgery information form (PDF)(What is a PDF document?) to help you prepare for this surgery.
References
Citations
- American Academy of Ophthalmology (2011). Cataract in the Adult Eye (Preferred Practice Pattern). San Francisco: American Academy of Ophthalmology. Available online: http://one.aao.org/CE/PracticeGuidelines/PPP_Content.aspx?cid=a80a87ce-9042-4677-85d7-4b876deed276.
- Allen D (2011). Cataract, search date May 2010. Online version of BMJ Clinical Evidence. Also available online: http://www.clinicalevidence.com.
- Harper RA, Shock JP (2011). Lens. In P Riordan-Eva, JP Whitcher, eds., Vaughan and Asbury's General Ophthalmology, 18th ed., pp. 174-182. New York: McGraw-Hill.
Other Works Consulted
- Riaz Y, et al. (2006). Surgical interventions for age-related cataract. Cochrane Database of Systematic Reviews (4).
Credits
ByHealthwise Staff
Primary Medical ReviewerKathleen Romito, MD - Family Medicine
E. Gregory Thompson, MD - Internal Medicine
Adam Husney, MD - Family Medicine
Specialist Medical ReviewerCarol L. Karp, MD - Ophthalmology
Current as ofMarch 3, 2017
American Academy of Ophthalmology (2011). Cataract in the Adult Eye (Preferred Practice Pattern). San Francisco: American Academy of Ophthalmology. Available online: http://one.aao.org/CE/PracticeGuidelines/PPP_Content.aspx?cid=a80a87ce-9042-4677-85d7-4b876deed276.
Allen D (2011). Cataract, search date May 2010. Online version of BMJ Clinical Evidence. Also available online: http://www.clinicalevidence.com.
Harper RA, Shock JP (2011). Lens. In P Riordan-Eva, JP Whitcher, eds., Vaughan and Asbury's General Ophthalmology, 18th ed., pp. 174-182. New York: McGraw-Hill.