15 Sep Diabetic Retinopathy Vs. Macular Degeneration (Part 2 of 2)
Good Morning! This is part 2 of 2. Part 1 was posted yesterday. Read Part 1.
6. Treatment with Avastin® or other anti-VEGF inhibitors
Technically, both diseases may be treated with anti-VEGF inhibitors.
Presently, I sometimes treat the neovascular component of diabetic retinopathy with Avastin® if pan-retinal laser photocoagulation (standard treatment) fails. More often, using Avastin® as an off-label drug, I will treat diabetic macular edema that is not responding to laser treatment.
Macular degeneration is usually not treated (most cases are the dry form), whereas the “wet” form of macular degeneration is usually treated with anti-VEGF therapy.
7. Cataracts are like Grey Hair, Some at an Early Age and Some Later, but Everyone Gets Them
Patients with diabetes usually develop cataracts earlier than the general population. Remember, cataract surgery is usually best performed when the retinopathy is stable.
There is no proven association between cataract surgery and macular degeneration. While both do usually occur with advancing age, there is no known cause-effect relationship.
Everyone gets cataracts…………eventually.
8. Macular Edema – “swelling” of the macula
Diabetic macular edema develops from abnormalities of the normal retinal blood vessels. Normal blood vessels do not leak fluid or blood. Blood vessels of a diabetic tend to lead over time (say 5-10 years). When the swelling involves the macula, vision may decrease. Treatment usually involves laser treatment, but may, these days, also include Avastin®, Lucentis®, Macugen® or steroids.
Swelling of the macula may occur in the “wet,” or exudative, form of macular degeneration. Abnormal blood vessels (aka neovascularization) can develop underneath the retina and leak or bleed.
9. Lack of Symptoms and Home Monitoring
A patient with diabetes may develop diabetic retinopathy and not know it. Vision may be perfect and there are no symptoms. Home monitoring is not too valuable. It is best to have regular eye exams with your doctor.
A patient with macular degeneration, by definition, has loss of vision (a symptom). Thus, patients with known macular degeneration should have at least one symptom (the decreased vision) and should be aware of the disease. Other symptoms included persistent distortion in the vision. Home monitoring with the Amsler grid is commonly recommended.
In either case, to make the diagnosis of either macular degeneration or diabetic retinopathy, your doctor should consider evaluation with a flourescein angiogram and OCT.
10 In closing, there are very few souls that have both macular degeneration and diabetic retinopathy. While this is not a hard fact, it is rare, in my experience, to see a patient with both diseases. It is as though one protects from the other. Others have noted this, and I welcome any one’s comments either way.
Read Part 1.
Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist