Secondary cataract is a condition that can be seen in 20% to 50% of patients within 5 years after cataract surgery. However, there is no need to worry. In fact, this condition does not answer the question of whether cataracts recur. To briefly answer the question of what secondary cataract is, it is not a real cataract but a result of the natural healing process after surgery.
In this article, we will explain the causes, symptoms, and especially the treatment methods of cataracts performed with YAG laser in detail.
What is Secondary Cataract?
After cataract surgery, a true cataract cannot form on the artificial lens placed inside the eye. The artificial lens is made of plastic or other synthetic materials and does not become opaque like the natural lens of the eye. However, during the surgery, the back membrane of the lens capsule is intentionally left in place to keep the artificial lens stable.
This back membrane helps maintain the position of the artificial lens in the eye for about 6 months after surgery. The legs of the lens adhere to the eye tissue during this time, and the membrane’s function is completed. Over time, the lens epithelial cells remaining in this back capsule begin to proliferate. As the cells multiply, the capsule thickens and loses its transparent structure.
This condition is medically referred to as “posterior capsule opacification” and is commonly known as “lens clouding” or “secondary cataract.” It is not a new cataract formation but rather the thickening and clouding of the membrane left during surgery. This process can occur months or years after the surgery.
Do Cataracts Recur?
Most patients who have undergone cataract surgery wonder, “Has the cataract formed again?” The answer is clearly no. The natural lens removed during surgery does not come back. Since the artificial intraocular lens is made of plastic, cataracts cannot develop again.
The deterioration in vision comes not from the lens itself but from the capsule that remains behind it. Therefore, secondary cataract does not mean surgical failure. It is a result of the natural healing process and can be easily treated.
If you have had cataract surgery in one eye, primary cataracts may develop in the other eye over time. This situation is independent of the artificial lens and is related to the aging process of the natural lens in the other eye.
Difference Between Secondary and Primary Cataract
Primary cataract is the clouding of the natural lens in individuals who have not undergone surgery due to aging or other reasons. It generally develops slowly over the years. Secondary cataract, on the other hand, is the clouding that occurs on the remaining back capsule after surgery.
From a source perspective, primary cataract is a deterioration of the lens’s own tissue. In secondary cataract, the lens has already been removed, and the problem is cellular proliferation in the capsule membrane.
The treatment methods are also different. The definitive treatment for primary cataract is surgery. Secondary cataract is mostly treated with YAG laser capsulotomy, which does not require surgery. Therefore, the treatment of secondary cataract is much simpler and faster.
In terms of timing, once primary cataract is treated surgically, the same natural lens cannot become cloudy again. However, secondary cataract can appear months or years after surgery.
Causes and Risk Factors of Secondary Cataract
There are multiple reasons behind the formation of secondary cataract. These reasons are related to both the surgical process and the patient’s own characteristics.
Proliferation of Capsule Cells After Surgery
During cataract surgery, some cells on the lens capsule may remain in the eye when the lens is removed. These cells are called “lens epithelial cells.” The surgeon tries to clean these cells during the surgery, but some cells may remain hidden in the corners of the capsule at a microscopic level.
After the surgery, the natural healing processes in your eye come into play. During this period, lens epithelial cells become active and start to proliferate. The cells form a thin membrane on the back capsule. Growth factors such as transforming growth factor-beta play a role in this process. Your body secretes these substances for tissue healing, but they can lead to unwanted clouding in the eye.
As the cells migrate and proliferate, the capsule thickens. Over time, it loses its transparent structure, and your vision becomes cloudy again. This process can be delayed but cannot be completely prevented.
Age and Cell Activity
Your age directly affects the rate of secondary cataract development. In younger patients, cell renewal and proliferation occur much faster. Therefore, the cells remaining in the eye after surgery multiply more actively.
Secondary cataract is almost inevitably common in childhood cataract surgeries. It has been reported that 41% of pediatric patients undergoing YAG laser capsulotomy develop recurring opacities.
In older patients, however, the natural lens cells are less active. Therefore, secondary cataract may occur less frequently or later in elderly patients. However, even in completely healthy individuals, posterior capsule opacity can occur after cataract surgery.
Diabetes and Other Systemic Diseases
Diabetes is one of the significant factors that increase the risk of secondary cataract. Secondary cataracts are more common in diabetic patients. In uncontrolled diabetes, glucose levels rise, which increases the sugar levels in the eye fluid and lens.
There is an enzyme in your lens that converts glucose into a substance called sorbitol. When sorbitol accumulates, it affects the cells and alters the healing process in the eye. Diabetes can also increase the risk by affecting wound healing and inflammation levels.
Cataracts also frequently develop in individuals undergoing corticosteroid treatment. The risk of secondary cataract is higher in eyes with uveitis, patients with retinitis pigmentosa, and traumatic cataracts.
Type of Lens Used and Surgical Technique
The type of artificial lens used during surgery plays an important role. It has been reported that patients with hydrophobic intraocular lenses develop less posterior capsule opacity compared to those with silicone and polymethyl methacrylate lenses. High-quality lenses made from hydrophobic materials adhere well to the back capsule and do not allow clouding.
Modern surgical techniques and sharp-edged artificial lenses can prevent lens epithelial cells from migrating to the back capsule. The surgeon’s experience and how meticulously the capsule is cleaned during surgery also determine the risk. In high-quality lenses, clouding may not be seen for an average of 2 to 4 years, and sometimes even after 10 years.
What are the Symptoms of Secondary Cataract?
Months or years after surgery, you may notice changes in your vision again. These changes generally develop slowly, so they may initially go unnoticed. However, over time, the symptoms become more pronounced and start to affect your daily life.
Blurred Vision and Haze
The most common symptom of secondary cataract is blurred vision. Patients often describe it as “there is a thin veil in front of my eyes” or “I feel like my glasses are dirty, but even if I clean them, it doesn’t improve.” Your eyes, which got used to seeing clearly after surgery, experience haze again over time.
This blurriness is similar to the windows of your house getting dirty over time. The image that was once crystal clear now obscures the clarity of the outside world. Clarity is lost at both near and far distances. For example, you may feel that you are struggling again to read a newspaper or drive a car.
You may also feel like your glasses prescription is changing frequently. However, even if you get new glasses, the problem will not improve, because the source of the blurriness is not the glasses prescription but the opacification in the back capsule.
Sensitivity to Light and Glare
When you look at a light source, you may see halos, glare, or diffusion. Especially at night, you may experience seeing halos around car headlights and street lamps. These halos make light sources appear brighter and more diffuse than they actually are. Therefore, night driving can become problematic for many people.
In bright sunlight or bright lighting, your eyes may glare. You may feel an increased desire to squint. Traveling by car during the day can also become uncomfortable. Working under fluorescent lights can start to feel tiring.
Difficulty in Reading and Night Vision
You will especially feel a loss of clarity in fine tasks. Tasks that require detail, such as threading a needle or reading small print, become difficult. Your eyes tire quickly when reading books or looking at a phone screen.
Significant difficulty in night vision begins. It becomes harder to distinguish objects in dark environments. Blurred vision or trying to focus can strain your eyes and brain. Occasionally, you may experience tension around your eyes, headaches, and concentration problems.
Changes in Color Perception
Colors are perceived as faded and lacking vibrancy. Colors that you once saw vividly may now appear more dull and muted. You may find it difficult to distinguish the color tones of your clothes. This situation may not always be noticed, but especially those involved in art or with high color sensitivity can easily feel this difference. Additionally, double vision may rarely occur, where you see two slightly shifted copies of the same image with one eye.
Diagnosis and Treatment of Secondary Cataract
After listening to your complaints, your doctor will perform a comprehensive eye examination. This process consists of several basic steps.
Eye Examination and Diagnostic Methods
In the visual acuity test, how clearly you see with or without glasses is measured. Your clarity level after surgery is compared with your current condition. In the biomicroscopy examination, your pupil is dilated with drops. The doctor examines the position of the artificial lens and the amount of cloudiness in the back capsule under high magnification. This examination is a critical stage in the diagnosis of secondary cataract.
In the fundus examination, the retina and optic nerve are checked. If the back capsule is very opaque, this examination may be difficult, but it is necessary to evaluate the retina since there may be other causes of visual impairment. In the retroillumination method, light is sent into the eye to make the opaque areas more distinct. If necessary, advanced imaging methods such as optical coherence tomography are used.
What is YAG Laser Capsulotomy?
YAG laser capsulotomy is the gold standard for treating secondary cataract. This method opens a small window in the opaque area of the back capsule. Thus, light falls clearly on the retina again. The procedure is not surgery; it is completed within a few minutes in an outpatient setting. It does not require stitches, cuts, or dressings.
How is the YAG Laser Procedure Applied?
First, your pupil is dilated with drops. Then, anesthetic drops are applied, so you will not feel any pain. You sit in the examination chair and place your chin and forehead on the device. Your doctor focuses on the back capsule and vaporizes it with laser shots. The procedure takes an average of 2-3 minutes. Usually, 5-15 laser shots are applied.
No instruments touch your eye, which minimizes the risk of infection. You will only feel brief flashes of light. After the procedure, your eye is not covered.
Recovery Process After Treatment
Visual clarity usually significantly improves on the same day or within a few hours. You may see blurry for the first 6 hours, but afterwards your vision level becomes better than before the procedure. Usually, 1 or 2 eye drops are prescribed and are requested to be used for 4-5 days.
You may see some floaters in front of your eye for a few days. These will continue until the fragments of the back capsule dissolve, but they will disappear within a few days. Patients can return to their normal lives the next day. Once the back capsule is vaporized with laser, it does not form again.
Risks and Complications of Treatment
YAG laser capsulotomy is a very reliable procedure. However, complications may rarely occur. An increase in intraocular pressure occurs in 1.8% of cases. Uveitis occurs in 0.74%, macular edema in 0.74%, macular hole in 0.33%, corneal edema in 0.25%, retinal detachment in 0.16%, and retinal tear in 0.08% of cases.
The risk of retinal detachment is about 1%, but after YAG laser capsulotomy, this risk increases to about 2%. Care should be taken, especially in highly myopic eyes. If you experience sudden vision loss or severe pain, you should contact your doctor immediately.
Methods and Recommendations for Preventing Secondary Cataract
It is not possible to completely prevent secondary cataract. However, some precautions can reduce the risk of formation or prepare the ground for early diagnosis.
Regular Check-ups After Surgery
After cataract surgery, you need to go for regular check-ups every year. These examinations are important not only for secondary cataract but also for other eye problems such as glaucoma and macular degeneration. The first follow-ups after surgery are usually done on the 1st day, 3rd day, and 3rd week. Afterwards, your doctor will recommend an annual follow-up program.
To catch the chance of early diagnosis, you should not skip these check-ups. If intervention is made while symptoms are mild, both your comfort will increase and vision loss will be minimized. Especially individuals over 40 years old should have an eye examination at least once a year. Regular examinations ensure the early detection of possible opacification.
Management of Systemic Diseases
If you have chronic diseases such as diabetes or hypertension, controlling these values is critically important for your eye health. Uncontrolled blood sugar negatively affects the healing process in the eye and can accelerate the formation of secondary cataract.
Your average blood sugar level, or HbA1c, should be at an ideal level before surgery. After surgery, you should pay more attention to blood sugar regulation for the first month than usual. Regular retinal examinations should also be performed after surgery in diabetic patients.
Keeping your blood sugar levels under constant control will keep the lens of the eye clear and healthy. Therefore, it is important to follow your doctor’s recommendations regarding nutrition and blood sugar control.
Lifestyle Supporting Eye Health
Healthy lifestyle habits positively contribute to your eye health. Quitting smoking and limiting alcohol consumption support overall eye health. Smoking can lead to many eye diseases, including cataracts and macular degeneration.
A balanced diet supports the overall health of eye tissue. Be sure to consume foods rich in omega-3 fatty acids, vitamins C and E. Foods rich in fruits, vegetables, and antioxidants can delay age-related eye problems.
Wearing UV-protected sunglasses is essential. UV rays increase the risk of cataracts in the long term. Regular exercise and getting enough sleep also benefit your eye health.
Frequently Asked Questions About Secondary Cataract
Patients often ask some questions after surgery. These questions generally focus on similar topics. Below you will find answers to the most frequently asked questions.
How long does it take for secondary cataract to develop?
Secondary cataract largely appears within 2 to 4 years after surgery. However, in some individuals, this period may be longer than 5 years. The quality of the lens used and the surgical technique directly affect this duration. In high-quality lenses, clouding may not be seen for an average of 2 to 4 years, and sometimes even after 10 years.
It does not develop at the same speed in every patient. In some individuals, it may not occur within the first year, but vision blurriness may begin three or four years later. This period can be shorter, especially in young patients and diabetic individuals.
Is the YAG laser procedure painful?
No, the YAG laser procedure is not painful. Anesthetic drops are applied to your eye before the procedure, so you will not feel any pain or discomfort. You may see only brief flashes of light. No instruments touch your eye during the procedure, which provides comfort.
Will there be clouding again after the procedure?
Secondary cataract does not recur once treated. The reason is that the tissue causing secondary cataract has been completely removed. Once the back capsule is vaporized with YAG laser capsulotomy, it does not form again, and no new clouding will be seen. The opened capsule does not become cloudy again. An eye that has undergone cataract surgery will not require another intervention for life.
Does secondary cataract require surgery?
No surgery is required for the treatment of secondary cataract. The treatment is performed with YAG laser in outpatient conditions. The procedure is usually completed within a few minutes. It does not require stitches, cuts, or dressings. Patients can return home the same day after the procedure.
In which patients is the risk of secondary cataract higher?
Secondary cataract is almost inevitably common in childhood cataract surgeries. The risk is also higher in diabetic patients. Family history, hypertension, or certain metabolic syndromes can increase the risk. Individuals with additional eye conditions such as uveitis, trauma, retinitis pigmentosa, or high myopia may be predisposed to the development of secondary cataract. The incidence is higher in patients under 60 years old due to the rapid healing potential of young tissues.
In Summary: Secondary Cataract
Secondary cataract is not a surgical failure but a result of the natural healing process. There is no need to worry when you notice blurriness in your vision. YAG laser treatment resolves the issue within minutes and does not recur for life.
It is especially important to attend regular check-ups after surgery. This way, your chances of early diagnosis increase, and timely intervention can be made when necessary. If you have diabetes, keep your blood sugar under control.
If your cataract surgery was successful, the treatment for secondary cataract will also be successful. The only step you need to take to see clearly is to consult your doctor.
