{"id":18122,"date":"2026-08-11T11:07:59","date_gmt":"2026-08-11T11:07:59","guid":{"rendered":"https:\/\/www.eyecliniclondon.com\/blog\/?p=18122"},"modified":"2026-08-11T11:07:59","modified_gmt":"2026-08-11T11:07:59","slug":"history-of-oct","status":"publish","type":"post","link":"https:\/\/www.eyecliniclondon.com\/blog\/history-of-oct\/","title":{"rendered":"The History of Optical Coherence Tomography (OCT)"},"content":{"rendered":"

Optical coherence tomography has transformed the way your retina and optic nerve can be examined. It allows eye specialists to see microscopic structures inside your eye without surgery or taking a tissue sample.<\/p>\n

Since its introduction in 1991, OCT has progressed from relatively slow two-dimensional scans to fast, detailed three-dimensional imaging and OCT angiography. It is now an important tool for diagnosing and monitoring many retinal and optic nerve conditions.<\/p>\n

What Inspired the Development of OCT?<\/h2>\n

Researchers explored whether low-coherence interferometry could measure the position and structure of biological tissues using reflected light. This provided the scientific basis for obtaining depth information without physically entering or removing tissue from your eye.<\/p>\n

OCT compares light returning from your tissue with light travelling along a reference path. The resulting interference signal can be converted into highly detailed measurements of structures within your retina and other parts of your eye.<\/p>\n

Who Invented OCT?<\/h2>\n

James Fujimoto, David Huang, Eric Swanson and their collaborators at MIT and associated clinical centres were central to the invention and early development of optical coherence tomography.<\/p>\n

Fujimoto, Huang and Swanson received the 2023 Lasker\u2013DeBakey Clinical Medical Research Award for their contribution to OCT. Their work helped transform how your retina and optic nerve head can be examined and monitored without invasive tissue sampling.<\/p>\n

The Landmark 1991 OCT Paper<\/h2>\n

In 1991, David Huang, James Fujimoto, Eric Swanson and colleagues published the landmark paper introducing optical coherence tomography. Their early images included a human cadaver retina and other biological tissue rather than the retina of a living patient.<\/p>\n

The study demonstrated that low-coherence interferometry could produce cross-sectional images of internal tissue microstructure with micrometre-scale resolution. This established the scientific foundation for your modern OCT examination.<\/p>\n

Why Was the 1991 Discovery Important?<\/h2>\n

The early OCT images demonstrated structural detail on approximately the scale of individual tissue layers, with reported image resolutions of around 12 to 17 micrometres.<\/p>\n

Importantly, your retinal nerve fibre layer could be distinguished in these early images. This suggested that OCT might eventually allow clinicians to quantify structural changes associated with conditions such as glaucoma.<\/p>\n

The First OCT Images of the Living Retina<\/h2>\n

In 1993, Swanson and colleagues reported what they described as the first in-vivo OCT measurements of human retinal structure.<\/p>\n

This was a crucial step because your retina could now be imaged while your eye remained intact. The development moved OCT from laboratory tissue experiments towards practical clinical ophthalmic imaging.<\/p>\n

Early Research into Glaucoma<\/h2>\n

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By 1995, researchers had demonstrated that OCT could quantify your retinal nerve fibre layer and distinguish structural differences between normal and glaucomatous eyes.<\/p>\n

This was an important development in glaucoma imaging. Your OCT measurements can provide objective structural information, but they should be interpreted alongside your optic nerve examination, visual-field results, eye pressure and other clinical findings.<\/p>\n

Why Was This Glaucoma Research Important?<\/h2>\n\n\n\n\n\n\n\n\n\n
Aspect<\/strong><\/td>\nWhat It Means for You<\/strong><\/td>\nWhy It Matters for You<\/strong><\/td>\n<\/tr>\n
Your OCT measurement<\/td>\nYour scan can measure your retinal nerve fibre layer and other structures affected by glaucoma<\/td>\nYour clinician receives objective structural information about your eye<\/td>\n<\/tr>\n
Your structural assessment<\/td>\nYour scan can show thinning or other changes around your optic nerve<\/td>\nYour findings can support your wider glaucoma assessment<\/td>\n<\/tr>\n
Your comparison over time<\/td>\nYour repeated scans can be compared with earlier results<\/td>\nYour clinician may identify structural change or possible progression<\/td>\n<\/tr>\n
Your early structural changes<\/td>\nYour OCT may show changes before you notice a difference in your sight<\/td>\nYour clinician can investigate these findings alongside your other glaucoma tests<\/td>\n<\/tr>\n
Your glaucoma monitoring<\/td>\nYour scan provides repeatable numerical measurements<\/td>\nYour clinician can use these measurements as one part of your long-term follow-up<\/td>\n<\/tr>\n
Your complete assessment<\/td>\nYour OCT is interpreted with your visual fields, eye pressure and optic nerve examination<\/td>\nYour scan should not diagnose or monitor your glaucoma by itself<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

The First Commercial OCT<\/h2>\n

The first commercially available ophthalmic OCT system entered the market in 1996 after the technology was transferred from its academic developers and further developed for clinical use by Humphrey\/Zeiss.<\/p>\n

This was a major step in moving OCT from specialist research laboratories into routine ophthalmic practice.<\/p>\n

What Was Time-Domain OCT?<\/h2>\n

Early commercial OCT systems used time-domain technology. Your scan was created by mechanically changing the reference-arm position to sample reflections arising from different depths within your eye.<\/p>\n

This approach was relatively slow and limited how densely your retina could be sampled. Later generations increased acquisition speed dramatically, allowing much larger volumes of retinal data to be collected.<\/p>\n

The Shift to Fourier-Domain and Spectral-Domain OCT<\/h2>\n

A major technological advance came with Fourier-domain OCT, which could collect information from multiple tissue depths without mechanically scanning the reference arm in the same way as time-domain systems.<\/p>\n

In 2002, researchers reported the first in-vivo human retinal images obtained using Fourier-domain OCT. This approach subsequently developed into spectral-domain systems capable of much faster scanning and dense three-dimensional imaging.<\/p>\n

For your modern eye examination, this transition was one of the most important advances after the original invention of OCT because it allowed clinicians to obtain detailed retinal volumes rather than relying mainly on individual cross-sectional scans.<\/p>\n

How Did OCT Change Retinal Diagnosis?<\/h2>\n

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OCT allowed your clinician to examine cross-sectional changes within your retina, including retinal thickening, fluid accumulation and disruption of individual retinal layers.<\/p>\n

This became particularly useful in conditions such as age-related macular degeneration and diabetic macular oedema. Your OCT findings are interpreted alongside your symptoms, visual acuity, clinical examination and any additional imaging that may be required.<\/p>\n

The Rise of Anti-VEGF Treatment<\/h2>\n

The development of anti-VEGF treatment for neovascular age-related macular degeneration greatly increased the clinical importance of OCT. Repeated scans allowed your clinician to identify retinal or subretinal fluid and assess how your macula changed during treatment.<\/p>\n

Your OCT findings can therefore contribute to decisions about disease activity and retreatment. They should still be interpreted as part of your overall clinical assessment rather than as the sole determinant of treatment.<\/p>\n

Three-Dimensional Retinal Imaging<\/h2>\n

High-speed OCT systems can collect many closely spaced scans to create a three-dimensional dataset of your retina rather than relying only on isolated cross-sectional images.<\/p>\n

Your clinician can use these datasets to examine retinal thickness maps, assess specific layers and compare corresponding areas between visits. This helps identify structural change over time.<\/p>\n

Measuring the Optic Nerve in Glaucoma<\/h2>\n

Optical coherence tomography (OCT) has become an important tool for measuring your retinal nerve fibre layer and ganglion cell layers in glaucoma. This allows your clinician to assess the structure of your optic nerve with greater precision.<\/p>\n