Master Age-Related Macular Degeneration (AMD) with Picmonic for Physician Assistant

Dry (nonexudative) is the most common type and less severe form of AMD (90% of cases). It begins with the accumulation of yellow pigment in the retinal epithelium that leads to atrophy and degeneration of macular cells due to gradual blockage of the retinal capillaries. Dry AMD, even though it is less severe, still accounts for 10-15% of AMD-related blindness.

Wet (exudative) is the more severe form of AMD, and while it is only responsible for about 10-15% of the overall number of cases, it is responsible for 80-90% of AMD-related blindness. Those with wet AMD had dry AMD first, and wet AMD had a more rapid onset. It occurs as a result of the development of abnormal vessels in or near the macula. These new vessels begin to leak and form scar tissue.

Scotomas are defined as blind spots in the visual field and are a classic sign of AMD.

Patients often complain of blurred and darkened vision.

Loss of central vision is permanent, and once it is lost, treatment does not help. This permanent loss can have significant psychosocial implications for the patient. One can assure the patient that, while therapy will not recover lost vision, there are options to augment the vision that remain.

Distortion of vision, also referred to as metamorphopsia, is another manifestation of AMD.

Several medications injected into the vitreous part of the eye can aid in slowing vision loss. Bevacizumab (Avastin) or ranibizumab (Lucentis) are examples.

Another possible intervention for those with wet AMD is a surgical procedure known as photodynamic therapy (PDT). This procedure uses the drug verteporfin (Visudyne) and a laser. The light from the laser activates the verteporfin dye, thereby destroying the abnormal blood vessels without causing permanent damage to the retinal epithelium and photoreceptor cells.

Several low-vision assistive devices can be used to augment the remaining vision. These include devices such as magnifiers, large print books, and talking watches/clocks.