Especially after cataract surgery patients expect to see clearer with new transparent lenses inside their eyes compared to the cloudy one before surgery. But this unfortunately is not always thus surgery turns out. In seldom cases, patients see more blurred after cataract surgery than they did before. When the visual acuity is worse than before surgery even after 4-5 weeks the causes could be plenty.
- Malpositioned lens implant (decentration or tilted)
- Insertion of the wrong intraocular lens implant
- Inaccurate measurements
- Unstable position of the intra ocular lens implant in the capsular bag
- Corneal complications after cataract surgery
- Retinal complications after cataract surgery
- Drooping eyelid
- Wrong design of implanted lens
Unclouded vision is the goal of lens treatment to correct cataracts. Patients who suffered severely from the cloudy lens before treatment, in particular, are understandably very much looking forward to the experience of being able to see clearly and sharply again with their own eyes. All the greater the disappointment when the blurred vision persists after cataract surgery.
Malpositioned Lens Implant – When Vision Is still Blurry After Cataract Suergery
The little lens that gets inserted into your eye only has the perfect lens power when positioned optimally. A slight malposition like a tilt can easily induce unwanted astigmatism. A lens that is not centered correctly could also produce blurry vision, especially with multifocal lens implants.
In such a case the ophthalmologist uses technologies like Scheimpflug cameras to measure the position of the lens implant in the eye. When a malposition is present the lens needs to be repositioned. This takes another surgery.
The Wrong Design of the Implanted Lens
Before cataract surgery, the ophthalmologist speaks to you about the various options you have when it comes to the lenses. Some of them have blue light filters others produce a clear image in only one distance (monofocal) while other lenses enable you to see far and near (multifocal) but in most cases with slight drawbacks when it comes to image clarity.
Multifocal lens implants usually produce a slightly less clear visual experience in regards to the contrast and lead to more glare at night. Halo effects are also common. Usually, doctors test the lens design before cataract surgery with contact lenses. This way they see if glare for example is a problem for you.
But in some cases, this does not turn out as planned. This means the patient reacts sensitive to glare and is not satisfied with the visual acuity. In such a case another surgery needs to be done in which the lenses or one lens gets changed into a monofocal lens design. This way the drawbacks like halos or glare disappear.
Corneal Complications After Cataract Surefery That Could Lead To Blurry Vision
The surgeon needs to cut the cornea during cataract surgery. Otherwise, he or she would not be able to insert the lens implant. This of course stresses the tissue. In most cases, this is not a problem at all and after surgery, the cut just heals and the cornea stays stable. But in seldom causes the cornea’s rigidity could be impaired by the surgery and complications like an ectasia could show its shape.
When the cornea loses its rigidity fluctuations show up in the prescription on a daily basis. When the fluctuations are intense only specialty contact lenses are an option. Usually, those changes in the prescription show up in astigmatism and the axis. When refraction is done the patient perceives the numbers or characters presented two times instead of one time. Or they might have shadow effects.
Has your vision deteriorated again after successful cataract surgery? Or were you implanted with a multifocal lens and after some time you no longer see as sharply as you did directly after the operation? An easily repaired opacity behind the artificial lens may be the cause.
What Is a Posterior Cataract?
During cataract surgery, the clouded lens is removed from the lens capsule surrounding it. However, the natural lens capsule remains in its position in the eye and polished smooth.
The artificial lens is then inserted into this lens capsule, which can be imagined as a bag stretched open in the eye. After a few months or years, however, the capsule may become cloudy because lens epithelial cells grow on the capsule or the capsule undergoes connective tissue remodeling.
This is called post-cataract. If the clouding penetrates into the optical center, the visual acuity decreases, the vision becomes blurred and poorer in contrast.
In a short outpatient laser procedure, the surgeon creates a small central hole in the clouded lens capsule so that light can once again reach the retina unimpeded (YAG capsulotomy). The laser treatment is quick and painless.
Blurred Vision After Surgery
Blurred vision in the first 48 hours after cataract surgery is quite normal. This is because the eye and the brain must first get used to the new vision. Most patients notice an initial significant improvement in the quality of their vision within the first few days after treatment. However, the healing process and the increase in visual acuity take about four weeks. The treating ophthalmologist checks the restoration of visual acuity at regular follow-up examinations.
Blurred Vision After Monofocal Lens Surgery
During monofocal lens implantation, the clouded natural lens is replaced with a high-quality, new lens. The relief from the blurred vision alone is already perceived by patients as a significant increase in quality of life. The major disadvantage of the monofocal lens, however, is that it can only optimize vision at one distance, usually distance vision. At all other distances, however, patients need a visual aid so it stays blurry in some distances.
Multifocal Lenses Enable Sharp Vision
Because many people with cataracts want not only unclouded vision but also good vision at all distances, many opt for multifocal lens treatment. These have significant advantages over monofocal lenses: multifocal lenses have multiple focal points (multi = many), allowing patients to see well at near, far, and intermediate distances.
When the patient did not fully grasp the concept of multifocal lenses he or she might understand vision would be great at all distances and at all times. But with less bright light the diameter of the pupil changes and with this change the visual experience during day and night. Of course, when expectations are set incorrectly another surgery needs to take place to switch lens implants to another option.
In a lot of cases, glasses or contact lenses can also improve visual acuity. But of course, the surgeons give their best so you can see clearly without glasses.