Optical coherence tomography is a non-invasive (non-contact) method for studying the structure of the eye tissue. It allows you to get higher resolution images compared to the results of ultrasound procedures. In fact, optical coherence tomography of the eye is a type of biopsy, only for the first one there is no need to take a tissue sample.
A Brief History
The concept behind modern optical coherence tomography was developed by researchers at the Massachusetts Institute of Technology back in the 1980s. In turn, the idea of introducing a new principle into ophthalmology was proposed in 1995 by the American scientist Carmen Pouliafito. A few years later, Carl Zeiss Meditec developed a corresponding device, which was called the Stratus OCT.
At present, with the help of the latest model, it is possible not only to study retinal tissues, but also optical coherence tomography of the coronary arteries, the optic nerve at the microscopic level.
Research principles
Optical coherence tomography consists in the formation of graphic images based on the measurement of the delay period when a light beam is reflected from the tissues under study. The main element of devices of this category is a superluminescent diode, the use of which makes it possible to form light beams of low coherence. In other words, when the device is activated, the beam of charged electrons is divided into several parts. One stream is directed to the area of the studied tissue structure, the other - to a special mirror.
Rays reflected from objects are summed up. Subsequently, the data are recorded by a special photodetector. The information generated on the graph allows the diagnostician to draw conclusions about the reflectivity at individual points of the object under study. When evaluating the next piece of fabric, the support is moved to another position.
Optical coherence tomography of the retina makes it possible to generate graphs on a computer monitor that are in many ways similar to the results of an ultrasound examination.
Indications for the procedure
Today, optical coherence tomography is recommended for diagnosing pathologies such as:
- Glaucoma.
- Macular tissue tears.
- Thrombosis of the circulatory pathways of the retina.
- Diabetic retinopathy.
- Degenerative processes in the structure of the eye tissue.
- Cystoidswelling.
- Anomalies in the functioning of the optic nerve.
In addition, optical coherence tomography of the optic nerve is prescribed to evaluate the effectiveness of the therapeutic procedures used. In particular, the research method is indispensable in determining the quality of the installation of a drainage device that integrates into the tissues of the eye in glaucoma.
Features of diagnostics
Optical coherence tomography involves focusing the subject's vision on special marks. In this case, the operator of the device performs a number of sequential tissue scans.
Significantly complicate the study and prevent effective diagnosis are capable of such pathological processes as corneal edema, profuse hemorrhages, all kinds of opacities.
The results of coherence tomography are formed in the form of protocols that inform the researcher about the state of certain tissue areas both visually and quantitatively. Since the data obtained are recorded in the memory of the device, they can subsequently be used to compare the state of the tissues before the start of treatment and after the application of therapies.
3D rendering
Modern optical coherence tomography makes it possible to obtain not only two-dimensional graphs, but also to produce a three-dimensional visualization of the objects under study. Scanning tissue sections at high speed allows you to form amore than 50,000 images of the diagnosed material. Based on the information received, special software reproduces the three-dimensional structure of the object on the monitor.
The generated 3D image is the basis for studying the internal topography of the eye tissue. Thus, it becomes possible to determine the clear boundaries of pathological neoplasms, as well as fix the dynamics of their change over time.
Advantages of coherence tomography
Coherence tomography devices are most effective in diagnosing glaucoma. In the case of using devices of this category, specialists get the opportunity to determine with high accuracy the factors in the development of pathology in the early stages, to identify the degree of progression of the disease.
The research method is indispensable in diagnosing such a common disease as macular degeneration of the tissue, in which, as a result of age-related characteristics of the body, the patient begins to see a black spot in the central part of the eye.
Coherence tomography is effective in combination with other diagnostic procedures, such as fluorescein angiography of the retina. By combining procedures, the researcher obtains particularly valuable data that contributes to the correct diagnosis, determination of the complexity of the pathology and the choice of effective treatment.
Where can I get an optical coherence tomography?
The procedure is possible only if there is a specializedOCT device. Diagnostics of such a plan can be resorted to in modern research centers. Most often, vision correction rooms and private ophthalmological clinics have such equipment.
Issue price
Carrying out coherence tomography does not require a referral from the attending physician, but even if one is available, diagnostics will always be paid. The cost of the study determines the nature of the pathology, which is aimed at identifying the diagnosis. For example, the determination of macular tissue ruptures is estimated at 600-700 rubles. While tomography of the tissue of the anterior part of the eye can cost the patient of the diagnostic center 800 rubles or more.
As for comprehensive studies aimed at assessing the functioning of the optic nerve, the state of the retinal fibers, the formation of a three-dimensional model of the visual organ, the price for such services today starts from 1800 rubles.
