Let's first talk a bit about how we see. Our eyes are like windows to the outside world. There are two transparent structures that allow light to enter through these windows: the cornea and the lens. Light rays coming from different angles and distances pass through the cornea at the front of the eye and the lens inside the eye, refracting and focusing on the macula within the eye. The macula is the central region of the eye layer that enables vision. This way, we achieve clear vision. The lens adjusts its refractive power to allow clear vision at different distances. Generally, after the age of 40, the elasticity of the lens decreases, leading to problems with near vision. As age progresses, its transparency also decreases, and cataracts develop. Smart lenses are artificial, multifocal lenses equipped with technology that allows light rays coming from different distances to focus on the macula. These lenses are placed in place of the lens that has lost its transparency and elasticity, aiming to eliminate the need for glasses. Standard single-focal intraocular lenses used after cataract surgery have only one focal point, requiring glasses for near vision.
Are They Really Smart? How Many Types of Smart Lenses Are There?
Actually, whether they are single-focal or multifocal, the patient's treatment is successfully completed after cataract surgery. The difference with these lenses is that they have multiple focal points. This way, they eliminate the need for glasses. That's why they are known as smart lenses. In fact, there is no such terminology in medical language. Basically, we can categorize the most commonly used lenses today into two groups: trifocal (three-focal) lenses and extended depth of focus (EDOF) lenses. Trifocal lenses provide vision at far, intermediate (arm's length), and near distances, while EDOF lenses offer vision at far and intermediate distances.
Which Lens is Better?
Rather than which lens is better, it is important to determine which lens is more suitable for which patient. After using the right lens for the right patient, a good surgical procedure will yield good results. Therefore, the patient's needs and the condition of their eyes are evaluated. The patient's living conditions, expectations, and work life play an important role in the choice of lens. Patients are evaluated with various measurements before surgery, and the most suitable lens is chosen. As long as there are no problems in the layers of the eye that enable vision (macula, retina) and the visual pathways in the brain, different alternative solutions that will eliminate or minimize the use of glasses are possible for each patient.
Can Smart Lenses Be Used for Every Patient?
They are mostly used in the treatment of cataract patients over the age of 40. They can also be used in the treatment of patients with high eye numbers who do not want to use glasses but are not suitable for laser treatment. Patients who have undergone laser treatment also develop near vision problems after the age of 40. Smart lenses can also be used in the treatment of these patients. It is not suitable to use trifocal lenses, especially for patients with macular degeneration (functional impairment in the macula), patients who have developed bleeding at the back of the eye due to diabetes (diabetic retinopathy), patients with advanced glaucoma (in short, patients with developed retinal problems), and patients with irregularities in the cornea. Single-focal or EDOF lenses may be more suitable for these patients. With these lenses, the need for glasses can also be reduced or eliminated.
What is the Difference from Cataract Surgery?
There is no difference. The basic principles are the same, but the lens placed inside the eye is different. While single-focal lenses can correct distance vision, near vision requires glasses. With multifocal smart lenses, this need is eliminated.
What are the Risks? Is the Result Permanent?
As a result, every surgical procedure carries some risk. The risk of surgery performed with the correct diagnosis, correct technique, and equipment is very low. Cataract surgery is one of the safest and most effective surgeries. The result is permanent and usually does not require additional intervention. The patient's eye numbers are adjusted to be zero at far, intermediate, and near distances. In some patients, decreased vision may develop due to cloudiness developing in the capsule where the lens is placed, and cleaning with a laser in the clinic may be necessary in the future.
What is the Surgery Process? What is the Follow-Up Treatment Process?
First, the patient is thoroughly examined, and the most suitable lens is selected based on their living conditions, expectations, and the condition of their eyes. The operation is outpatient. Before the procedure, the patient's eye is numbed with drops, and after that, there is no pain or discomfort. The operation is performed using the phacoemulsification (phaco) technique, known as sutureless cataract surgery or laser cataract surgery. The procedure takes about 10 minutes. Afterward, the patient's eye is covered, and they are discharged and sent home, without the need for hospitalization. The next day, the patient's eye is opened, checked, and the patient begins to see on the same day. The surgery on the other eye is performed a week later. Controls are carried out in the first week and the first month, and the control interval is extended over time. Drop treatment is used for about a month.
Op. Dr. Eren GÖKTAŞ
Ophthalmology
