OCT - a window to retina

ABSTRACT

Optical coherence tomography [OCT] is a non-contact, non invasive imaging modality that helps diagnosing a variety of diseases involving the eye. It provides quantitative measurements of retinal nerve fiber layer [RNFL], optic nerve head and macular thickness parameters 1, 2 and can be used as a valuable tool in many intraocular surgeries. This article discusses the applications of different OCT systems available commercially for diagnosing and managing various ophthalmic conditions. Furthermore, future directions of OCT technology, clinical uses and benefits are also discussed. Different articles published till year 2014 majorly in between 2005 to 2014, obtained from online search engines Pubmed and Google Scholar were used in preparation of this review. Those articles were included that contained information regarding OCT and its uses in various ophthalmologic conditions and its future advancements. We excluded those articles that did not contain relevant information regarding OCT and its uses. Due to advancements in OCT technology, it is now possible to reveal the structural changes associated with retinal diseases that help in improving early analysis and monitoring of disease progression and response to treatment. Three generations of OCT have been introduced till date. Early versions of this technology i.e. OCT 1 and OCT 2 are relatively slow, limiting both the amount of data to be captured and the quality of image. The older versions required dilation of the pupil but the latest version, the Stratus OCT can be used without dilating the pupil.3 Commercially, OCT is employed in diverse applications including diagnostic medicine, interventional cardiology and art conservation. Ophthalmology is still the most important field of OCT application because of transparent ocular structures