Ocular: Retinal Anatomy By OCT Flashcards
What is optical coherence tomography (OCT)?
-non-invasive, non-contact diagnostic technique that images an in-vivo cross section of the retina
What does OCT use to image the retina?
Interferometry within 10-15 microns
What light is typically used in OCT?
Light in the near-infrared spectral range
When was first generation OCT patented?
2006
Time-domain:
Two-dimensional imaging method based on low-coherence interferometry
Spectral domain:
Provides improved axial resolution, and increases scanning speed of more than a factor of 50
Swept source:
Overcomes light scattering by the RPE, which disabled visualization of the deeper lying structures, longer wavelength adopted, photodectors instead of camera led to. A further increase in resolution
How is the OCT image produced?
The superposition of both waves creates an interference pattern that is used to measure echos vs depth profile of this tissue
How is time domain OCT image acquired?
Superluminescent diode, single photon detector, moving mirror
Spectral domain OCT image acquisition:
Broadband superluminescent diode source, an array of detectors, fixed mirror
Swept source OCT imaging acquisition:
Swept-source turntable laser, single detector
Range of time OCT imaging:
Vitreoretinal interface to RPE
Range of imaging for spectral-domain OCT:
Posterior cortical vitreous to sclera using enhanced depth imaging
Range of swept source OCT imaging:
Posterior cortical vitreous to sclera
Important uses for OCT:
-diagnosing post and ant seg diseases
-lesions in macular region easier to
