Astigmatism

Astigmatism is blurry vision produced by a football-shaped cornea that is too steep in one place and too flat in another. Astigmatic corneas focus light in two different places in the eye, making both near and distance vision a problem.

Best Corrected Visual Acuity (BCVA)

The best possible vision a person can achieve with corrective lenses measured in terms of Snellen lines on an eye chart.

Bilateral LASIK

Surgery performed on both eyes on the same day

Cornea

The cornea is sometimes referred to as the "window of the eye".

It provides most of the focusing power when light enters the eye. The cornea is composed of five layers of tissue. This is the part of the eye reshaped by laser vision correction.

Custom LASIK

A custom treatment is a wavefront-guided procedure.

However, every procedure we perform at the Excimer Laser Vision Centre is a "customised" procedure as your examination is a highly detailed, personalised evaluation. We carefully assess your eyes with our wavefront technology, which is the NIDEK OPD Scan, and then adjust and customise your treatment depending on your pupil size, refraction, corneal topography and all other test results.

The ability to adjust the NIDEK EC-5000 CXII Excimer Laser's optical zone size and transition zone allows for a truly customised treatment. The adjustability of the laser is one of the most important factors in providing a customised treatment for each individual patient.

Dioptre

A measurement of the degree to which light converges or diverges; also a measurement of lens refractive power.

EpiLASIK

EpiLASIK is an innovative new procedure designed to restore natural vision with the help of an epikeratome.

The surgeon uses an epikeratome, a separator that creates an epithelial sheet, to make a thin flap in the epithelium. The Wavefront based excimer laser beam is then applied under the epithelial flap to successfully correct refractive errors and restore clear vision.

Epithelium

The outer layer of the cornea that acts as the eye's protective layer.

Higher-Order Aberrations

The ideal eye would have no aberrations, with light entering the eye focusing to a perfect point on the retina. Higher-order aberrations are very subtle aberrations.

Our objective in your treatment is to minimise your resulting aberrations. With the NIDEK EC-5000 CXII Excimer Laser technology, we can reduce or minimise halos and glare and higher order aberrations. Higher-order aberrations do not always affect vision.

ICL

Implantable Contact Lens (ICL) are indicated for patients unsuitable for LASIK with extremes of myopia (near-sightedness), hyperopia (far-sightedness) and/or astigmatism.

Implantable Contact Lens (ICL) are often used to correct vision in patients unsuitable for LASIK (thin corneas, high nearsightedness, etc).

They are designed to correct visual problems much the same way as an external contact lens. Unlike external contact lens, Implantable Contact Lenses are placed inside the eye behind the iris (colored part of the eye) and in front of the eye's natural lens.

Unlike LASIK, the ICL is a reversible procedure.

LASIK

LASIK (Laser-In-Situ Keratomileusis) is currently one of the most frequently performed elective procedures.

It is a highly effective outpatient procedure that is suitable for treating patients with shortsightedness, long sightedness and astigmatism.

In LASIK, a protective hinged flap is created and then gently lifted by the surgeon. Then, a computer controlled cool beam of light from the Excimer laser is used to gently reshape the front surface (cornea) of your eye.

Lens

The lens is the clear structure located behind the pupil. Its primary function is to provide fine-tuning for focusing and reading, which it accomplishes by altering its shape.

Lensectomy

Surgical removal of the lens, usually done by puncture incision through the ciliary disk during vitrectomy.

Normally, the natural lens is removed only when it has become cloudy enough to obstruct vision, for example, when a cataract has formed in our latter years of life. The lensectomy procedure, however, can also be used to correct very high amounts of short-sightedness or long-sightedness.

Lid Speculum

An instrument, placed in the eye before surgery, to gently hold the lids apart, eliminating possibility of blinking.

Long-sightedness (Hyperopia)

A refractive effort in which you see better from a distance than close. An eyeball that is too short to focus light on the retina causes hyperopia.

Lower-Order Aberrations

Also called refractive error; includes myopia (short-sightedness), hyperopia (farsightedness) and astigmatism.

Monovision

The laser can be used to focus one eye at a reading distance, so that close tasks can be performed without glasses. This procedure is known as monovision.

Presbyopia

Presbyopia. People often require reading glasses over 40yrs of age because the focusing mechanism of the eye becomes inflexible.

The laser can be used to focus one eye at a reading distance, so that close tasks can be performed without glasses. This procedure is known as monovision.

PRK

PRK involves sculpting the surface of the cornea by removing minute amounts of corneal tissue to alter the radius of curvature and the focus point of the eye.

The surface layer of the eye (the epithelium) is first removed and laser pulses then ablate the deeper stromal tissue. The amount of corneal tissue to be removed is directly dependant on the size and type of refractive error.

PRK has been used successfully on thousands of patients worldwide.

Pupil

The pupil is the “black circle” in your eye.

The primary function of the pupil is to control the amount of light entering your eye. When you are in a bright environment, the pupil becomes smaller to allow less light to pass through. When it is dark, the pupil expands to allow more light to reach the back of your eye.

Retina

The retina consists of fine nerve tissue that lines the inside wall of the eye and acts like the film in a camera.

Its primary function is to capture and transmit images.

Short sightedness (Myopia)

Shortsightedness is also known as myopia and is the result of the eye's lens system being too powerful relative to the length of the eye.

Myopic people can see well up close but distant objects like street signs or the television appear out of focus.

As the images we see are brought into focus by the cornea as well as the lens, vision correction can be achieved by the reshaping of the corneal surface. The cornea can be made flatter and less powerful thereby making these distant objects clearer.

Our laser and computer technology can correct low, moderate and high levels of shortsightedness.

Uncorrected visual acuity (UCVA)

The best possible vision a person can achieve without corrective lenses measured in terms of Snellen lines on an eye chart.

Wavefront Diagnostic Equipment

Wavefront is helpful in determining if you have significant pre-operative higher order aberrations and this information can be used to determine the best way for treating your eyes.

At the Excimer Laser Vision Centre we use the OPD-Scan as it very accurately measures higher order aberrations as it uses 1440 points of infra red light in comparison to other brands of equipment only using 200 points of visible light.

This OPD Scan also more comprehensively maps the eye's optical system as it uses over 8000 points to measure the characteristics of your eye.

Hence the OPD Scan results can then be used in conjunction with the NIDEK EC-5000 CXII Excimer Laser to minimise the creation of new aberrations.