Definition & Overview
Phacoemulsification is a cataract removal surgery that involves taking out the front portion of the eye lens while retaining the posterior capsule. It is a safe, painless procedure followed by the implantation of an artificial lens (IOL) in the affected eye to improve vision.
Eye cataract is the clouding of the eye’s natural lens, leading to considerable vision loss especially among people beyond the age of 40. There are several types of cataract, classified according to the location where it occurs. Clouding at the back portion of the lens is termed subscapular cataract, while the one that forms in the nucleus of the lens is called a nuclear cataract. A cortical cataract, on the other hand, starts at the periphery of the lens and spreads inwards toward the center. To some degree, the formation of cataract is related to aging, though more and more people are afflicted with it due to diseases and other medical conditions.
Who Should Undergo and Expected Results
Patients with cataract are advised to undergo phacoemulsification, especially those who need to maintain good visual acuity for driving, flying, or operating machineries and equipment. The procedure is safe and can be performed on patients of all ages, including infants with congenital cataract and older individuals.
Patients who are at a higher risk of developing cataract can also consider the procedure. These include diabetic, hypertensive, and obese patients as well as those who experienced injury and trauma to the eye that resulted in cloudy or hazy vision.
Phacoemulsification has a high success rate, with patients reporting improved vision and the ability to perceive color and depth more accurately following the procedure. In a large study, 95 out of 100 adult patients were satisfied with the results reporting increased mobility and independence and relief from the fear of going blind. Those who were not happy with the results had other existing eye problems such as macular degeneration and glaucoma.
How is the Procedure Performed?
Prior to the procedure, the patient is subjected to a complete eye exam where the ophthalmologist uses ultrasound or laser scanning device to check the affected eye thoroughly. The tests are meant to determine the best IOL for the patient.
Phacoemulsification is an outpatient procedure that can be performed either under local (adult patients) or general anesthesia (paediatric patients). Using a microscope, the surgeon makes a small incision in the eye, at the side of the cornea. A viscoelastic fluid is then injected to cushion the intraocular tissue and reduce shock. Another incision is made in the membrane surrounding the cataract so it can easily be separated from the cortex using water stream. A titanium needle called a phaco probe is then inserted into the cornea and directed into the central nucleus of the cataract where it is most dense. This device oscillates at great speed to break up the cataract into minute pieces, which are then suctioned by a small hole at the tip of the probe. As the central core of the cataract is emulsified and removed, the probe moves into the peripheral part of the lens and the front part of the lens capsule is removed, as well as some part of the natural lens. A folded intraocular lens is then implanted into the capsule bag using an injector and unfolded in place. This permanent implant replaces the front portion of the natural lens while the remaining back portion of the lens holds the inserted lens in place. The viscoelastic fluid introduced at the start of the procedure is then removed.
Phacoemulsification can also be performed using laser technology. This method involves the use of a specialised machine that makes the incision and softens the cataract so it can be easily removed. The procedure follows the same method as traditional phacoemulsification but since laser technology is used instead of a knife, it offers quicker recovery time and is more accurate.
Depending on the technique used, the incisions may be closed with very small stitches or self-sealing method is performed. Patients with stitches are scheduled for a follow-up for the removal of the said sutures.
The surgery lasts about an hour and can only be performed one eye at the time. Patients with cataracts in both eyes are typically scheduled for cataract removal sessions that are spaced two weeks apart.
Possible Risks and Complications
Based on studies, one in 10 patients develop complications from phacoemulsification and the risk is higher in those who have other eye diseases aside from cataract.
Among the risks and complications that come with the procedure are:
- Adverse reactions to anesthesia and bleeding
- Endophthalmitis, or the inflammation of the inner parts of the eyeball
- Retinal detachment - Following surgery, patients may see dark spots that should disappear after several weeks. If this condition is not resolved, it could be an indication of retinal detachment, a serious complication that could have a lasting effect on the patient’s vision.
- Itching sensation in the eye
- Eye discharge
- Cataract recurrence, with the condition developing from the remaining back portion of the lens capsule
- Glaucoma - In some rare cases, glaucoma can develop following phacoemulsification, which could lead to total blindness
Corneal edema, or the swelling of the clear covering of the eye
American Academy of Ophthalmology Cataract and Anterior Segment Panel. Preferred Practice Pattern Guidelines. Cataract in the Adult Eye. Available at: www.aao.org/preferred-practice-pattern/cataract-in-adult-eye-ppp--october-2011. Accessed September 10, 2015.
Moorman C. Cataract surgery. In: Spaeth GL. Danensh-Meyer HV, Goldberg I, Kampik A, eds. Ophthalmic Surgery: Principles and Practice. 4th ed. Philadelphia, PA: Elsevier; 2012:chap 4.
Tipperman R. Cataracts. In: Gault JA, Vender JF. Ophthalmology Secrets in Color. 4th ed. Philadelphia, PA: Elsevier; 2015:chap 21.