Science & Research

There are certain tests that your ophthalmologist can perform to help distinguish between the two causes of blurred vision that you mentioned in your question. One such test is called the PAM (potential acuity meter) test. If your vision improves with PAM, then cataract may be contributing to your decreased vision, and surgery to correct this condition might help improve your vision.

Quality of vision is not always accurately reflected by the level of visual acuity. A person can test fairly well on the eye chart, but still have poor quality of vision due to factors such as decreased contrast sensitivity, cataract, decreased visual field, etc. It is also possible that someone with relatively preserved central vision may not see well due to a decrease in peripheral vision. With advanced dry macular degeneration, a condition known as geographic atrophy may occur. Geographic atrophy consists of areas of the macula which have become thin and atrophied and no longer function well, resulting in "patchy" vision. Your mother's ophthalmologist may be able to explain if any of the above factors are contributing to her decreased quality of vision.

There are many potential causes of blurry vision after retinal detachment repair. Silicone oil in the eye changes the refractive error of the eye, and you may need glasses to correct your vision. Your description of "distorted" central vision may also be consistent with an epiretinal membrane, which you can think of as cellophane wrap on the surface of the retina that causes wrinkling of the retina and consequently, distortion of central vision. Epiretinal membranes are common after retinal tears/detachments. Retinal detachment repair with vitrectomy/gas can also result in significant acceleration of cataract development. If you have not had prior cataract surgery, it is possible that a cataract is contributing to your symptoms. Your own ophthalmologist can examine you and diagnose which, if any, of the above reasons may be causing your blurry vision.

Plavix should not accelerate the pathogenesis or progression of wet macular degeneration. However, it does decrease the clotting ability of blood, and as such, could potentially result in a larger hemorrhage if the abnormal blood vessels in wet macular degeneration start to bleed. Regardless, your ophthalmologist would probably not recommend taking you off Plavix or any blood thinners prescribed by your medical doctor, given that your use of this medication may be reducing your risk of a potentially life-threatening stroke.

Lucentis, although injected directly into the eye, can theoretically escape into the bloodstream and increase the risk for adverse events such as stroke, heart attack, etc. The risk of this is low, but may be higher in people who are already prone to blood clots. Another medication, Macugen, has also been used to treat wet macular degeneration. It is thought to have fewer systemic side effects than Lucentis or Avastin, but is also less efficacious than the latter two medications. In addition, both photocoagulation and photodynamic therapy have been used to treat wet macular degeneration. New medical therapies are also in the pipeline. You should ask your ophthalmologist about the other treatment modalities that would be best for you.

Macular corneal dystrophy refers to a disease that affects the cornea, the clear part of the eye on which contact lenses rest. It is inherited in an autosomal recessive* fashion, and results in corneal clouding. In contrast, vitelliform macular dystrophy and macular degeneration are conditions that affect the macula (the center of the retina, in the back of the eye). Macular dystrophies are usually inherited and present in younger individuals than age-related macular degeneration. The pathophysiology of vitelliform macular dystrophy and age-related macular degeneration (AMD) is also different, but both diseases result in decreased central vision because they affect the portion of the retina that is responsible for clear central vision.

*Autosomal recessive: Two copies of an abnormal gene must be present in order for the disease or trait to develop.

In wet age-related macular degeneration, abnormal blood vessels form underneath the macula (the portion of the retina responsible for clear central vision) and leak/bleed, resulting in decreased vision. Macular translocation is the last resort for patients who have not responded to intravitreal injections. The procedure is technically very challenging, and consists of multiple surgeries. In the first surgery, cataract extraction with intraocular lens implantation is performed, followed by a 360 degree cut of the peripheral retina. The retina is then purposely detached and rotated so that the macula can be placed over an area that is free of abnormal blood vessels. Laser is applied to the periphery of the rotated retina and silicone oil is injected into the patient’s eye. Later surgeries consist of eye muscle surgery to rotate the eye*, and to remove the silicone oil. Some studies, including a recent publication from the United Kingdom, have shown a success rate of approximately 25% in improving and preserving visual acuity over a period of a few years, which is why the procedure is generally a last resort in patients with wet age-related macular degeneration. You should ask your father's retinal surgeon about his or her success rate and experience with this complex surgery.

* If the retina is rotated without eye muscle surgery, the patient will have double vision.

Anti-VEGF injections for wet macular degeneration may be beneficial if bleeding from the abnormal choroidal vessels has not yet resulted in macular scarring. If your physician believes that injections are no longer of any use, it is possible that you have irreversible scarring in the macula (the region of the eye responsible for central clear vision). However, you should still visit your doctor regularly for dilated exams on your right eye. If your right eye develops wet age-related macular degeneration, injections may be beneficial both in preserving and improving vision. You should also visit your ophthalmologist for a vision check to see if you still qualify for a driver's license at your current level of vision.