Diagnostic Tests

Optic Coherence Tomography

Optic coherence tomography (OCT) is an imaging method, allowing the macula and optic nerve head in particular to be seen. It is ot an invasive method. OCT provides high-resolution information about the internal structure of the retina using the reflecting properties of tissues helped by close laser light beyond red. As the eye is composed of clear material from the front to the back as far as the macula, it is possible by this method to obtain information in the same way as taking a live biopsy slice. According to the degree of reflection of the retaina structure, slices are coloured differently and each cell layer of the retina can be seen separately.


Figure 1. Optical coherence tomography appearance of cystoid macular oedema(upper) and full thickness macular hole (lower).

Figure 2. Optical coherence tomography appearance of epiretinal membrane (upper) and choroidal neovascularization secondary to wet age-related macular degeneration (lower).

Thus, we can obtain structural information about the normal and pathological tissues as well as volumetric dimensions and by looking at different reflections, information about the internal structures. In addition to the use of optic coherence tomography in macula oedema, macula hole, epiretinal membrane, age-related macular degeneration and optic disc pathologies, it is also used in the evaluation of the retinal nerve fibre layer particularly in glaucoma, and in the visualisation of anterior segment structures. There are no known side-effects.


Figure 3. Optical coherence tomography appearance of optic atrophy.


Figure 4. Optical coherence tomography angiography appearance of a healthy individual (left) and a patient diagnosed with choroidal neovascularization secondary to wet age-related macular degeneration (right).