The anterior segment is the front third of the eye that includes the structures in front of the vitreous humour like the cornea, iris, ciliary body, and lens. The anterior segment suffers from several disorders, the most common being a cataract.
Structure of the Anterior Segment
- The anterior segment consists of two fluid-filled spaces known as the anterior chamber and the posterior chamber.
- The anterior chamber lies between the corneal endothelium and the iris.
- The posterior chamber lies between the iris and the front face of the vitreous.
- It also consists of the aqueous humour which fills these spaces within the anterior segment and provides nutrients to the surrounding structures.
Examination of the anterior segment of the eye
An OCT adapted to a slit lamp is used to measure the corneal radius and the central corneal thickness. Likewise, the depth and the volume of the entire anterior chamber can be determined by the surgeon.
A slit lamp with the help of a microscope is used by the examiner to view the eye at many times the magnification.
Since the microscope has a light source it can be swiveled to both sides. This light produces a slit-shaped, focused light beam that passes through the transparent parts of the eye. The surgeon moves this light beam slowly across the eye at the appropriate magnification. This helps the surgeon notice any changes in the cornea or the lens clearly.
Ophthalmologists and optometrists specialize in the treatment and management of anterior segment disorders and diseases such as
- Dry eye and blepharitis
- Contact-lens related problems
- Corneal ulcers
- Herpes simplex and herpes zoster infections
- Keratoconus and other ecstatic disorders
- Allergic conjunctivitis
- Bacterial and viral conjunctivitis
- Ocular cicatricial pemphigoid
- Trauma to the cornea, conjunctiva and anterior segment including iris trauma
- Refractive errors (myopia, hyperopia, and astigmatism) etc.