“I had cataract surgery 6 months ago but I’m still having blurry vision.” I see patients here at Miami Eye Center who come to see me for a second opinion totally distraught over the issue and in many instances their degree of concern is unwarranted. This could be you, if so there are several things to consider. Firstly, what is the cause of the blurriness and secondly, can it be fixed?”
We can start analyzing the problem from the front of the eye (cornea) and working to the back (retina). Some of the issues are simple yet overlooked while others are complex. If you have had a multifocal lens implant there is no margin of error as these lenses are unforgiving. If your tear film is not good you could be losing vision. I have many patients complain of poor acuity only to find that by putting a drop of artificial tears on their eye they recover substantial vision. A long term program of tear film enhancement leads to continued excellent vision.
There could be residual nearsightedness, farsightedness and or astigmatism. If this is the case and you have had a multifocal lens implant it is incumbent upon the surgeon to correct this. If you have opted for a generic lens implant, eyeglasses is the answer. However, with multifocals you should be offered LASIK correction which has the potential to completely correct the blurry vision.
The intraocular lens is placed into the eye on a clear membrane (like Saran wrap) called the posterior capsule. On occassion this clear membrane becomes cloudy and impacts the vision potential. This is easily treated with a Nd:YAG laser procedure which vaporizes the membrane and thus clears the vision.
Moving to the back of the eye there is the retina. If there is a problem with the retina it is the same as taking a photograph with bad film in the camera. In a small percentage of surgeries there could be swelling of the retina known as cystoid macular edema. This has a profound effect in reducing the vision. Fortunately, it is self limited to several weeks to months and often responds to therapeutic eye drops.
While the point of this discussion is to inform the reader that all is not lost if at first glance the outcome of cataract surgery appears to be less than optimum, however, there are a number of complications which require extensive evaluation and complex repair. One must keep in mind that if you lump all of the possible complications of cataract surgery into one, the risk is about 3%, one of the safest major surgical procedures performed today.
The macular is the very center of the retina and when there is damage to this area there is loss of central vision and a preservation of peripheral vision. The important point here is that the retina surrounding the macular is healthy and functional. If a person with macular degeneration looks at your face while standing in front of you, they will not see your eyes or nose but will see your ears because the image of your ears falls on healthy retina. Needless to say, this is debilitating and frustrating.
Along came VisionCare Ophthalmic Technologies, a research and development company that has developed and tested a lense that is implanted in the eye at the time of cataract surgery which magnifies the light image entering the eye by almost three times and projects an image on to the retina outside the macular region and on to normal retina. This lens has been studied for the last two years and it has been found that 60% of the patients had substantially improved vision with significant increases in quality of life. They had less difficulty watching TV, recognizing family and friends, seeing facial expressions and reading large print books.
The good news is that that this lens technology has obtained FDA approval and is now awaiting approval by Medicare. At present this lens is approved for patients with cataracts and severe vision loss in both eyes from dry macular degeneration. The lens is implanted in only one eye.
Here in Miami, I have been helping patients with both wet and dry forms of macular degeneration for quite some time. To this point, there has been little to offer those with the dry type of the condition other than nutritional supplementation. This lens represents the first significant help to come along.
If you are interested in discussing this technology and how it might be of help to you, call me at Miami Eye Center and I will be happy to bring you the full details of this exciting breakthrough.
When your headlights flash an animal in the road you see the bright orange reflex of light from the retina (pictured to the left). While that was man’s first image of the interior of the eye the view is now down to the microscopic level. The device which makes that possible is Optical Coherence Tomography or OCT. We can visualize early and subtle changes in the retina and optic nerve in many cases before they are noticed by the individual.
How is this done? The patient is seated before the OCT machine and waves of safe invisible ultraviolet light are beamed into the eye. The light is reflected back just as it is with the headlight. The reflected light is captured by a sensing devise (interferometer) and passed along to a computer which interprets the variations in the reflection as various anatomic parts of the retina and optic nerve.
Anatomic Details of the Retina The complex structure of the retina, pictured here, passes the visual information along its nerves to the Optic Nerve which in turn feeds the image to the brain. All this processing takes about 2/10ths of a second. Needless to say, small anatomic problems in the retina can cause big problems with the vision. So it becomes important to view the anatomic changes asssociated with disease early in their evolution. This can also be said about diseases of the Optic Nerve such as glaucoma.OCT Image of the Retina
To the practiced ophthalmologist, the image to the right represents all the layers of the retina in sideways view. One can see early signs of macula degeneration, swelling due to diabetes or other circulatory problems as well as impending holes.
The diagnosis of glaucoma is often made difficult because the eye pressure is normal and the optic nerve appears normal. In this situation the OCT can be invaluable as it identifies early damage to the nerves as they enter the Optic Nerve. Not only does it identify the problem areas but it serves as a baseline for future comparisons and assessment of the progress of the disease. People with a strong family history of glaucoma would do themselves a service with an OCT screening.
In Miami, as elsewhere, the incidents of glaucoma is quite high, and as a diagnostician, I employ all the aids available in the armamentarium. Call for an appointment if you are concerned about any of these issues and I will be pleased to give you a thorough examination and opinion.
Most of my patients think that astigmatism is a disease; it is not and it’s time to clear the air. Astigmatism is a normal condition effecting 80 percent of the population. Astigmatism is caused by an irregular shape of the cornea; the clear window on the front of the eye is the cornea. In a non-astigmatic eye it has a round curve in all directions, like a basketball. In the case of astigmatism, it is shaped like a spoon. In one direction there is a steep curve and in the other there is a gentle curve. This is called “regular astigmatism.” When light passes into the eye it must pass through the cornea. When there is no astigmatism the light comes to a perfect focus on the retina and the vision is excellent. When light passes through an astigmatic cornea light from different directions is focused differently and there is a blurry image projected onto the retina.
Regular astigmatism is easily corrected with eyeglasses or contact lenses. If you hold your glasses out in front of you and look at a picture on the wall while rotating the glasses you might see some changing distortion; this is the lens correcting your astigmatism. Rigid gas permeable (hard) contacts are excellent at correcting astigmatism while soft lenses are less effective.
There are excellent surgical techniques for the correction of astigmatism. The oldest method that I began using in 1982 is astigmatic keratotomy. Here small straight incisions are made on the cornea across the steeper curve (meridian). This tends to flatten that meridian and steepen the flatter meridian, ultimately making the cornea more spherical. Along came LASIK where after several years there emerged an algorithm for the correction of astigmatism along with nearsightedness and eventually along with farsightedness. Very substantial amounts of astigmatism can be corrected with LASIK. More recently, we have added a variation of astigmatic keratotomy (AK), known as limbal relaxing incision (LRI). Here the corneal incision is moved to the outer edge of the cornea and is curved rather than straight. It is more predictable than AK.
When patients come for cataract surgery we always evaluate their astigmatism. This is done so that we can calculate the power of the lens to be implanted at surgery and also to be in the position to offer them an opportunity to have the astigmatism corrected with LRI at the same time. The purpose is to enable patients to achieve excellent vision without glasses when the cataract surgery is done. We usually reserve the LRI for small amounts of astigmatism because there now is available the toric lens. This is an intraocular lens with optics designed to neutralize the astigmatism along with the correction of myopia or hyperopia. This lens is implanted just as any lens might be then it is rotated into a position to match the steep meridian on the cornea, thus neutralizing the astigmatism.
So don’t be concerned when you learn that you have astigmatism; it could be a lot worse.
