Optical Coherence Tomography, more commonly known as OCT, is a diagnostic test with the ability to evaluate both the anterior segment of the eye (cornea, anterior chamber, lens and iris) and the posterior segment (vitreous-retinal interface, retina and optic nerve).
Regardless of the ocular structure being evaluated, OCT can help diagnose and monitor the evolution of various pathologies.
The OCT is a non-invasive examination that can be performed quickly, in about fifteen minutes. Most of the time no preparation is needed to perform it, however, for a better performance of the OCT, the patient is asked to remove contact lenses, if used, and sometimes it may be necessary to use eye drops to dilate the pupil, in order to allow a better visualisation of the ocular fundus. During the examination there is no contact with the patient's eye.
Anterior segment OCT is important in situations where there may be alterations in the central and peripheral structures of the anterior segment, or in cases where there is a need to measure the angle between the cornea and the iris and the depth of the anterior chamber, the corneal thickness and also alterations in its structure.
It is also important to take into consideration that some pathologies that affect the transparency of the ocular media, such as cataract or corneal opacities, may hinder the capacity to acquire images.
It is an examination that allows the various anatomical structures to be mapped, including the retina, and is the only examination capable of differentiating its various layers in profile. With advances in technology, it is increasingly possible to obtain images with greater speed, higher resolution, with fewer artefacts and in 3D format.
