Retinal and vascular examination
Aftab Limited Surgery Center's Retina Diagnostic Services Department, equipped with the most advanced technology and staffed by highly trained specialists, offers a wide range of diagnostic services to its patients. Below, you will find an introduction to these services.
Angiography
For this test, Fluorescein or Indocyanine Green (ICG) is injected into a vein in the arm, and a fundus camera is used to capture images of the back of the eye. This test is used to examine the blood flow in the retina and choroid.
Typically, Fluorescein is used to assess retinal vessels, while ICG is used to evaluate choroidal vessels and deeper layers.
Fluorescein angiography is most commonly used for diagnosing diabetic retinopathy, vascular occlusive diseases such as retinal artery or vein occlusion, and for evaluating wet age-related macular degeneration (AMD).
ICG angiography, on the other hand, is particularly useful for detecting choroidal blood abnormalities, especially in cases of wet AMD.
Both dyes are considered very safe and are rarely associated with side effects. However, in rare cases, allergic reactions may occur.
ICG should not be used in individuals with iodine sensitivity.
Fluorescein may cause temporary yellowing of the skin or eyes and orange-colored urine for up to 24 hours after injection in some individuals.
OCT
This is a modern technique that provides ophthalmologists with valuable information about the retina by capturing high-resolution tomographic cross-sections of its layers.
It is widely used for the diagnosis and follow-up of various retinal diseases such as macular holes, macular edema, macular degeneration, diabetic retinopathy, and glaucoma.
Since this technique uses a light source rather than physical contact with the eye, it is non-invasive and can be performed within a few seconds.
Electroretinogram (ERG):
Assessment of retinal potentials using Flash and Pattern methods is one of the diagnostic capabilities of the ERG system available at Noor Super Specialty Hospital. These features enable the evaluation of a wide range of retinal diseases.
This test measures the retina’s overall response to a light stimulus by detecting the difference in electrical potential between two electrodes. One electrode is gently placed on the cornea, under the lower eyelid, while the neutral electrode is positioned on the skin around the eye.
To ensure patient comfort, anesthetic eye drops are used. In certain cases—such as when the patient is a child—general anesthesia may be administered.
This test is particularly useful for diagnosing retinal disorders such as cone dystrophy and retinitis pigmentosa.
Electrooculogram (EOG)
One of the key tests in electrophysiology is the Electrooculogram (EOG). It is used to evaluate the effects of medications as well as pathological changes in the eye. This test is primarily used to assess the function of the retinal pigment epithelium (RPE) and photoreceptors (rod and cone cells).
Under normal conditions, there is a 6-millivolt potential difference between the cornea and the retina. This voltage can be measured by placing electrodes on the skin on either side of the eyes.
During the test, the patient is asked to fixate on a light target that flashes intermittently. The light stimulus is arranged in such a way that it causes the eye to deviate approximately 30 degrees from its horizontal axis. The resulting electrical potential between the electrodes is amplified and recorded by the device.
This test is especially valuable for evaluating patients suspected of having disorders affecting the retinal pigment epithelium, such as retinitis pigmentosa.