The eye specialist may request a series of painless useful tests for the diagnosis of AMD. These tests will reveal if there is any damage in your eyes and/or impaired vision.
Visual acuity test. Measures your ability to see objects at different distances.
Amsler grid. A sheet of squared paper with a point in the centre, used to test if you notice any wavy lines or if any disappear.
Dilated eye exam. The doctor will need to apply a few drops which dilate the pupil in order to examine the inside of your eye. The effect of the drops can last from 4 to 24 hours, depending on the patient’s susceptibility.
Fundoscopy or ophthalmoscopy. A light source is used to examine the fundus (back) of the eye, i.e., the retina, the choroid, the blood vessels and the optic disc.
Optical coherence tomography (OCT). Imaging technique that uses light waves to take photographs of your retina and therefore measure and map its thickness.
Autofluorescence. Autofluorescence is a technique used to determine the area affected by retinal pigment epithelium (RPE) atrophy in patients with advanced dry AMD.
Eye fundus photography. The ophthalmologist uses a specially adapted camera to photograph the back of your eye.
Fluorescein angiography. This test examines the blood flow in the retina and the choroid, the rearmost layers of the eye.
Why do they have to dilate my pupils?
Dilating the pupils is a very common procedure during eye examinations. It is a totally painless process that allows the ophthalmologist to examine the fundus of your eye and determine the condition of your retina and optic nerve. It helps in the diagnosis of various eye diseases that may otherwise go unnoticed during early stages: macular degeneration, retinal detachment, glaucoma, diabetic retinopathy, etc.
The pupils are dilated by placing a few drops in the eye which act on muscles around the pupil, thus producing the dilation. These eye drops come in different types: some stimulate and others relax the iris muscles that dilate the pupil. Sometimes the ophthalmologist will use just one type of eye drop, and on other occasions they may combine different types, depending on the patient and the reason for dilating the pupil.
The drops may cause a slight itchiness just after they have been applied, but it is only temporary and will disappear shortly. You have to wait for 20 to 45 minutes after the drops have been instiled before your eyes dilate fully and the ophthalmologist can start the eye exam.
It is important for patients to take into account that the effects of dilation eye drops can last for several hours after the eye exam. Specifically, between 4 and 24 hours, or sometimes even more. This will depend on the type of drops used and each patient’s sensitivity. People are normally more sensitive to light and have blurred vision during this period in which the eye drops continue to have an effect. Although the effects will gradually disappear as the hours pass, patients are advised to wear sunglasses after receiving dilation eye drops and should be accompanied when they go to the eye exam. You must never drive after having your pupils dilated.
The effects of dilation eye drops last for longer in children than they do in adults. Similarly, blurred vision and sensitivity to light typically last longer in children than in adults.