Examinations of the anterior segment of the eye

OCT of the cornea, sclera, and iridocorneal angle

Optical coherence tomography (OCT) can be used to view the cornea, sclera, or corneal angle as a cross-section. A sensitive, safe laser scans the corresponding structure without touching it and displays it as a cross-section.

The OCT of the cornea does not require the administration of drugs, is painless, and takes only a few minutes for each eye.

OCT of a normal cornea
OCT of a normal cornea
OCT image of the sclera with iridocorneal angle
OCT image of the sclera with iridocorneal angle
OCT of both iridocorneal angles
OCT of both iridocorneal angles

Measurement of the anterior segment of the eye

An OCT adapted to a slit lamp can measure the corneal radius and the central corneal thickness. Likewise, the depth (= distance from the posterior corneal surface to the eye lens) and the volume of the entire anterior chamber can be determined.

A slit lamp is a microscope used by the examiner to view the eye at many times the magnification. The microscope has a light source that can be swiveled to both sides. This light produces a slit-shaped, focused light beam that shines through the transparent parts of the eye. The eyecare professional moves this light beam slowly across the eye at the appropriate magnification. Any changes, such as on the cornea or the lens, become visible.

 

Pachymetry (thickness measurement) of the cornea

With corneal pachymetry, the examiner obtains a quick overview of the cornea’s thickness at any point. This allows the measurement of structural changes in the cornea. The thickness of the cornea is an important parameter for carrying out refractive surgery (e.g., LASIK), the surgery that can correct your vision.

Corneal pachymetry
Corneal pachymetry

Digital gonioscopy

Digital gonioscopy is the examination of the corneal angle in the eye using an OCT instrument. Angles occur on both sides of the eye where the cornea and the iris come together. Extra fluid drains from the anterior chamber of the eye via these angles. If these drainage paths are blocked, this may result in increased eye pressure and thus in serious visual disorders. For this reason, it is important to observe, evaluate, and measure the angles.

Digital gonioscopy
Digital gonioscopy

In-vivo histology of the cornea and sclera

In-vivo histology of the cornea and sclera is a layer-by-layer analysis. A microscope creates images of each layer’s cell structure. The eyecare professional obtains insight into the cell structure and any pathological changes.

Epithelium at 30µm
Epithelium at 30µm
Stroma at 62µm
Stroma at 62µm
Stroma at 300µm
Stroma at 300µm
Endothelium at 572µm
Endothelium at 572µm