What is a cataract?
The human eye is analogous to a camera and the lens in an eye is analogous to the lens in a camera. It transmits light and can focus on distance or near objects by changing its shape. “Cataract” is an opacification of the natural crystalline lens in the eye. This opacification can happen due to many factors including age, injury, UV light exposure, and certain medication use. If left unchecked, the cataracts can cause loss of vision and subsequently decrease in activities of daily living for many people. In fact, cataracts are the leading cause of blindness in the developing nations.
How is a cataract visualized?
Cataracts are visualized through a careful ophthalmic exam with an experienced eye care provider. While shining oblique rays of light through the lens using a Slit lamp biomicroscope, the doctor can grade the amount and quality of the cataract. There are many different types of cataract including Nuclear Sclerotic, Posterior Subcapsular, and Cortical. Some people have one type predominantly while others have a mixture of these types of opacities.
What are symptoms of a cataract?
Although cataracts can present with a myriad of symptoms, the most common ones include:
- Decreased vision while doing distance tasks such as driving
- Decreased vision while reading
- Decreased contrast sensitivity
- Presence of Glare/halos especially around lights (example: oncoming headlights while driving)
When is cataract ready to be removed (extracted)?
That is a great question. Cataract is usually removed when it becomes visually significant and affects the activities of daily living for the patient. For example, if a patient was able to drive to the church group gathering in the evenings a year ago, but now does not feel confident because of glare around on-coming headlights, that could be considered visually significant based on the visual acuity.
How are cataracts removed?
Cataract extraction is an outpatient procedure. In the phacoemulsification technique, the cataract is accessed by the surgeon using a small incision (typically size is 2.4mm) in the cornea. Through this, the surgeon peels back the top layer (capsule) covering the cataract. Thereafter, the surgeon is able to break up the cataract into small pieces and remove them carefully out of the eye. After further cleanup of the capsule, a foldable lens in placed in the area. This lens is safe to stay in the eye for the rest of the patient’s life. There are many lens choices that are available to patients (see below) and typically the lenses are individualized to each patient. After the lens is placed, the area is cleaned further and the eye is pressurized. Typically, there is no suture or patching required. This latest form of small incision cataract surgery is often referred to “No stitch, No patch” surgery.
Why do I need an intraocular lens (IOL) during cataract surgery and what are my options?
Both the cornea and lens are used to focus the light onto the retina. When the natural cataract lens is removed, the power that the lens contributes to the visual system is also removed. If a lens was not implanted in the place of the cataractus lens, only the cornea would be responsible for focusing the light. This would result in very blurry vision because considerable amount of power would be missing. After the IOL is placed, the light is able to focus better on the retina.
There are a few options for intraocular lenses (IOL’s) available for patients.
- Standard monofocal lens
- Toric/astigmatism correcting lens
- Multifocal lenses
Standard monofocal lenses do not correct astigmatism. They can be targeted to correct for distance (more common) or near. Patients who chose this option may need spectacle correction to account for any residual astigmatism or refractive error.
The toric lens is a good option for patients who have significant corneal astigmatism. Astigmatism is a corneal condition where the shape of the cornea is slightly altered so that the light rays do not focus all in the same place without glasses correction. With correction by either intraocular lens or extraocular lens, this astigmatism can be corrected. The ophthalmologist will determine during the pre-operative assessment how much corneal astigmatism a patient has. This will help guide whether the toric lens is appropriate.
The multifocal lenses help the patients see both at distance and at near at the same time without the need of glasses. For most patients, this can be accomplished for greater than 90 percent of tasks. The patients may still require some correction in low lighting conditions or with finer print. Some patients experience glare or halos around lights after implantation of these multifocal lenses. These are usually transient and do resolve in a majority of patients. The ophthalmologist will determine during the pre-operative assessment whether a patient is a good candidate for these lenses.
What is Femtosecond Laser Assisted Cataract (FLAC) Surgery and is it necessary?
Laser assisted cataract surgery is similar to conventional cataract extraction except the first portion of the surgery is done with assistance from a Laser. This automation can be advantageous in certain types of cataracts and situations. Dr. Singh has been performing Laser Assisted Cataract surgery since 2012 in patients that would benefit from this technology.
What can I expect at the surgical center/hospital? Will I have general anesthesia for cataract surgery?
Typically, after checking in at the front desk, the patient will be assessed by the nurse. Thereafter, dilating drops are given and an IV is placed. During cataract surgery the patient is given mild sedation to make them comfortable and their eye is numbed. In this scenario, the patient is relaxed and pain free. This method of anesthesia allows for a safe and effective outpatient cataract surgery. At the conclusion of the case, patient is given post-operative drops and then given something small to eat. Discharge instructions are given to patients and family. Because anesthetics are given during the surgery, patients are not allowed to drive themselves home.
What is the recovery time?
Recovery time varies from patient to patient. Factors such as the density of cataract, age of patient, and the health of the eye all play a role in the time of reaching optimal visual recovery. Typically, the eyes take a few weeks to fully heal from cataract surgery. This is one of the main reasons why spectacle correction (refraction) is usually delayed till healing has occurred after a few weeks.
Will I need to use eye drops after cataract surgery?
Yes, eye drops are needed for optimal visual recovery after cataract surgeries. Typically, eye drops are given to reduce chance of infection and reduce post-operative inflammation. The eye drops are instilled with more frequency right after cataract surgery and then tapered with time.