Anterior segment OCT

Post Image

Anterior Segment OCT

Overview:

  • View in 3D: High-resolution imaging of the anterior ocular structures.
  • Speed: Approximately 5 minutes.
  • Resolution: Less than 3 microns.

What Is Optical Coherence Tomography (OCT)?

Optical Coherence Tomography (OCT) is an imaging technique that provides automatic, high-resolution scans of ocular structures. While traditionally used for the posterior pole, OCT has been adapted to also image the anterior segment of the eye. This adaptation allows for in vivo viewing with micrometric precision of the cornea, anterior chamber, iris, and crystalline lens.

What Does Anterior OCT Involve?

  • Non-invasive & Painless: The test is minimally invasive and involves no contact with the eye.
  • Infrared Light: The test works by emitting infra-red light, which reflects off ocular structures to create a 3D cross-cut map.
  • Technology: Various OCT technologies are used, including:
    • Time Domain (TD)
    • Spectral Domain (SD): Offers greater definition and faster scanning.
    • Swept Source: Provides clear peripheral cornea images and deep anterior chamber scans.

How Is Anterior OCT Performed?

  • Test Duration: The OCT is a quick test, lasting about 5 minutes.
  • Pupil Dilation: In some cases, dilation is needed (using mydriatic drops), which takes about 15 minutes to take effect.
  • No Contact Lenses Removal: Contact lenses do not need to be removed before the test.

When Is It Used?

Anterior OCT detects subtle changes in ocular structures, offering valuable insights beyond traditional slit lamp exams. It’s crucial for:

  • Corneal thickness assessment (e.g., in keratoconus or refractive surgery candidates).
  • Anterior chamber dimensions for intraocular lens implantation.
  • Iridocorneal angle analysis, particularly for closed-angle glaucoma.

Associated Pathologies:

  • Cataract surgery post-op monitoring
  • Keratitis
  • Keratoconus
  • Dry Eye Syndrome
  • Glaucoma (including congenital glaucoma)
  • Myopia, Hyperopia, Astigmatism
  • Pterygium
  • Corneal opacity
  • Corneal ulcer
  • Conjunctival tumors
  • Limbal stem cell deficiency treatment

Associated Treatments:

  • Cataract surgery
  • Laser refractive surgery
  • Corneal cross-linking
  • Glaucoma treatments (e.g., trabeculectomy, iridoplasty, cyclophotocoagulation)
  • Pterygium surgery with conjunctival autograft
  • Corneal transplantation (e.g., penetrating or lamellar corneal transplantation)

Posterior Optical Coherence Tomography (OCT)

Overview:

Posterior OCT is an imaging technique that provides high-resolution scanning of the fundus structures, enabling in-depth viewing of retina layers and the choroid (layer beneath the retina). OCT is critical in diagnosing and monitoring retinal diseases.