References:
- Brunner & Suddarth’s Textbook of Medical-Surgical Nursing, 15th Edition, ISBN 978-197-51-6103-3, by Janice L. Hinkle, Kerry H. Cheever, and Kristen J. Overbaugh (Ch. 58, [ebook] pp. 5103–5106)
The leading cause of irreversible blindness and visual impairment in the world. AMD is characterized by drusen (clusters of debris or waste material) beneath the retina. A wide range of visual loss is experienced. Only a small portion experience total blindness. Most patients retain peripheral vision. There are two types of AMD:
- Dry Type AMD makes up 85% to 90% of people with AMD. The outer layers of the retina slowly break down, with the breakdown forming drusen. If this drusen forms outside of the macular area, no symptoms generally occur. If it does, however, there is a gradual blurring of vision that patients may notice when they try to read.
- Wet Type AMD: the neovascular or exudative type. These have abrupt onsets and are more damaging to vision. Patients report that straight lines appear crooked and distorted, or letters in words appear broken. This is a result of proliferation of abnormal blood vessels growing under the retina, within the choroid layer (choroidal neovascularization). The affected vessels can leak fluid and blood, elevating the retina.
- Some patients may be treated with laser therapy to stop leakage from these vessels.
Medical Management
There is no known effective treatment or cure for dry advanced macular degeneration. An important component of treatment of wet AMD targets development and progression of angiogenesis. Vasoproliferation is believed to be caused by an underlying angiogenic stimulus (vascular endothelial growth factor; VEGF). Inhibitors for VEGF available by intravitreal injection include Ranibizumab and Brolucizumab.
Nursing Management
Amsler grids are given to patients to use in their homes to monitor for sudden onset or distortion of vision, potentially providing the earliest sign of progressing macular degeneration.
- These should be used several times each week for each eye with glasses on if necessary. Any changes should prompt the client to inform the ophthalmologist. Digital forms of these grids are also available.