Diagnosis: Optical Coherence Tomography (OCT)

Mark H. Nelson

Oct 18, 2023 — 1 min read

The OCT is one of the most important tests that a retinal ophthalmologist performs in order to diagnose and treat macular degeneration. It is a non-invasive technique that shows a cross-sectional view of the retina. It uses light - it is not an xray. As you can see in this normal OCT, the retina is composed of many layers. In addition to the retina, we also look at the area in front of the retina (vitreous) and behind the retina (choroid).

The picture below shows the left macula of a patient with Age-Related Macular Degeneration (ARMD). The photo on the left is how the macula appears when the doctor examines the eye - the optic nerve is on the left edge - the macula is in the central part of the photo. The green line represents the specific area of the macula that is being examined. The corresponding image on the right is the cross sectional view of the retina. One can see irregular thickness and elevations in the center part of the photo. On part 2 of this blog, I will give more information on how to look at an OCT.

The OCT will be performed when you are first examined and then during each subsequent exam to see if the disease has progressed or improved. Ask the photographer or doctor to show your OCT .

Exudative ARMD - Treatment Principles

Prior to the introduction of anti-VEGF drugs in 2006, the prognosis for patients with Exudative ARMD was not good. A small number of patients who were treated with thermal laser (prior to 2000) or PDT laser (after 2000) were lucky to have vision stabilized - better vision was not obtained.

What are the causes of vision loss?

Let's take an intermission prior to discussing Exudative ARMD. Obviously the most important concept of macular disease is vision loss. We all know that good vision was the norm in youth. We all know it becomes a challenge as we age. Here are the four reasons for vision loss: 1.

Diagnosis: Dry (Nonexudative ) versus Wet (Exudative) ARMD

Before delving into the finer details, let's look at couple of simple things. Dry ARMD is not the same as dry eyes, i.e. the tearing of dry eyes is in the front of the eye and has nothing to do with 'leakage' in the back part of the eye.

Diagnosis: Imaging Dyes (IVFA and ICG)

If your doctor finds leakage, or exudation, under your retina and the diagnosis of Exudative Age-Related Macular Degeneration (ARMD) is made, he/she may inject an imaging dye into your vein and take photos of the macula/retina. This test is critical to determine what type of Exudative ARMD you

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Exudative ARMD - Treatment Principles

What are the causes of vision loss?

Diagnosis: Dry (Nonexudative ) versus Wet (Exudative) ARMD

Diagnosis: Imaging Dyes (IVFA and ICG)