Abstract | Optička koherentna tomografija je nekontaktna, neinvazivna slikovna metoda. Otkako je ušla u kliničku praksu dijagnoza, liječenje i praćenje bolesnika s bolestima mrežnice i vidnog živca poprimili su sasvim drugačiju dimenziju. Napredovanjem OCT uređaja napreduju i mogućnosti rane dijagnostike, praćenja bolesti te u određenim slučajevima na taj način i sprječavanja težih posljedica bolesti. Temelj rada OCT-a zasnovan je na Michelsonovu interferometru. Pomoću mjerenja brzine svjetlosti, odnosno njezina povratna vremena i intenziteta odaslanog medija, stvara se gotovo histološka slika koja omogućuje vizualizaciju slojeva mrežnice. Prvi klinički prototip OCT uređaja dizajnirao je i napravio Eric Swanson 1993. godine. Nedugo nakon toga napretkom tehnologije počinju se razvijati napredniji i inovativniji uređaji koji stvaraju sve kvalitetniju sliku. Danas postoji nekoliko tipova OCT uređaja koji se razlikuju po principu rada. Primjerice time domain OCT (OCT vremenske domene, TD-OCT) koji ima rezoluciju 10 μm, SD-OCT (Fourier-domain) koji ima rezoluciju od 5 μm, te EDI-OCT (pojačana dubinska optička koherentna tomografija) kojom se koristi za bolji prikaz žilnice. Trenutačno najnaprednija tehnika snimanja kojom se postiže izrazito brzo stvaranje slike je Swept-source OCT. Neki od uređaja koji također unapređuju dijagnostiku su Doppler optička koherentna tomografija, optička koherentna tomografija prednjeg segmenta oka (engl. Anterior segment OCT, AS-OCT), OCT adaptivne optike (engl. adaptive optics OCT, AO-OCT) te OCT osjetljiv na polarizaciju (PS-OCT). Nedavno je komercijalno postala dostupna i OCT angiografija (OCTA) koja precizno otkriva neovaskularne lezije žilnice. Također jedan od iskoraka razvoja tehnologije je korištenje OCT-om za vrijeme operacija. Slikovne metode postale su neizostavan korak u oftalmološkoj dijagnostici. U današnje se vrijeme OCT-om u oftalmologiji koristi za dobivanje slika visoke rezolucije te proučavanje prednjeg i stražnjeg segmenta oka te time postaje dio svakodnevne kliničke prakse. Pomoću njega mogu se dijagnosticirati bolesti mrežnice poput makularne degeneracije i dijabetičnog edema makule, pratiti bolesti vidnog živca kao što je glaukom te prepoznati neuritis u sklopu multiple skleroze i druge očne bolesti u sklopu sistemskih patologija koje imaju očne znakove. |
Abstract (english) | Optical coherence tomography is a non-contact, non-invasive imaging method. Since it entered the clinical practice of diagnosis, the treatment and follow-up of patients with retinal and optic nerve diseases have taken on a completely different dimension. With the advancement of OCT devices, the possibilities of early diagnosis, monitoring of the disease and in some cases preventing more serious consequences of the disease are also advancing. The basis of OCT operation is based on the Michelson interferometer. By measuring the speed of light, i.e. its return time and the intensity of the transmitted medium, an almost histological image is created, which enables the visualization of the retinal layers. The first clinical prototype of the OCT device was designed by Eric Swanson in 1993. Shortly afterwards, with the advancement of technology, more advanced and innovative devices began to develop that created an increasingly high-quality image. Today, there are several types of OCT devices that differ in the principle of their operation. For example, the Time domain OCT (TD-OCT) with a resolution of 10 μm, SD-OCT (Fourier-domain) with a resolution of 5 μm, and EDI-OCT (enhanced depth optical coherence tomography) which is used for better vascular view. Currently, the most advanced imaging technique that achieves the expression of fast image creation is Swept-source OCT. Some of the devices that also enhance diagnostics are Doppler optical coherence tomography, anterior segment optical coherence tomography (AS-OCT), adaptive optics OCT (AO-OCT), and polarization-sensitive OCT (PS-OCT). Recently, OCT angiography (OCTA), which accurately detects neovascular vascular lesions, has also become commercially available. Also, one of the developments in this technology is usage of OCT during operation. Imaging methods have become an unavoidable step in ophthalmic diagnostics. Nowadays, OCT is used in ophthalmology to obtain a high-resolution image and to study the anterior and posterior segment of the eye, and in this way is becoming a part of everyday clinical practice. It can be used to diagnose retinal diseases such as macular degeneration and diabetic macular edema, to monitor optic nerve diseases such as glaucoma, to recognize neuritis in multiple sclerosis and other eye diseases which are a part of systemic pathologies. |