Glossary of Laser Eye Surgery Terms: I – M
IMPLANTABLE CONTACT LENSES
Implantable Contact Lenses are miniature contact lenses that are implanted inside the eye to correct vision instead of lying on the surface. They are made from a biocompatible material that will not be rejected by the body and so can be left in the eye permanently.
The lens is inserted through a small, self-sealing incision at the edge of the cornea and sits behind the iris, the coloured part of the eye. If required, the lens can be removed from the eye by a surgeon and it will return to its original state prior to the operation.
Intralase is a bladeless method of creating a corneal flap in preparation for laser treatment with an excimer laser. The Intralase laser is a quick and pain free process which only takes 15 seconds per eye.
The Intralase laser is a femtosecond laser that uses rapid pulses of light that pass through the top layers of the cornea and stop at a predetermined depth and position. These pulses of light form microscopic bubbles in the specified layer of the cornea. The bubbles are uniformly created as the laser moves across the eye, gently separating the tissue and produces the hinge for the corneal flap. This method allows for the creation of a smooth surface for the excimer laser to treat and produces stronger and thinner corneal flaps which reduces recovery time.
Advantages of the IntraLASIK method over conventional LASIK laser eye surgery include:
- Superior vision quality (e.g. minimal glare at night)
- quicker recovery time and faster healing
- Significantly reduced complication risk
- Increased predictability and enhanced safety
- Thinner, more precise, but stronger corneal flaps
This is the measurement of the fluid pressure inside the eye. The fluid in the eye (the aqueous humour) is made within the eye but drained continuously through a structure called the trabecular meshwork. If too much fluid is made, or if there is a blockage in the trabecular meshwork, the pressure within the eye will build up and cause damage to the optic nerve.
Like your fingerprints, no two irises are the same and this can be used to provide a unique identification. The Zyoptix z100 laser eye surgery system can scan your irises during the Zywave measurement and map the entire iris, generating a unique digital Zy-ID for each eye.
Keratoconus is a rare condition, often inherited, in which the cornea becomes progressively thinner and gradually bulges outward, causing blurred or distorted vision. The condition usually affects both eyes. Corneal cross-linking and INTACS eye surgery can stabilise the progression of the disease.
Acronym: Light Amplification by Stimulated Emission of Radiation. It is a high energy light source that uses light emitted by the natural vibrations of atoms (of a gas or solid material) to cut, burn or dissolve tissues for various clinical purposes: in the retina to treat diabetic retinopathy and macular degeneration to destroy leaking and new blood vessels (neovascularization); on the iris or trabecular meshwork to decrease pressure in glaucoma; after extracapsular cataract extraction to open the posterior lens capsule.
LASEK LASER EYE SURGERY PROCEDURE
LASEK is an abbreviation of Laser Epithelial Keratomilieusis and is also sometimes known as ‘Epi-Flap’. The LASEK laser eye surgery procedure is essentially the same as LASIK apart from the preparation of the cornea at the beginning of the procedure. In LASEK, the epithelium or outer layer of the cornea is placed aside with the help of a diluted alcohol solution instead of a corneal flap being created. Once the epithelial layer has been displaced, an excimer laser is then used to reshape the cornea, similar to LASIK laser eye surgery.
LASIK LASER EYE SURGERY PROCEDURE
LASIK laser eye surgery is a highly successful and popular procedure for vision correction that has been available for over 20 years. The process creates a thin-hinged flap on the cornea (front of the eye) using IntraLase (blade-free treatment).
This eye condition is noted by the reduced vision that is not correctable by glasses or contact lenses and is not due to any eye disease. This is usually a contra-indication to laser treatment. Mild forms can sometimes be helped by laser treatment but if the vision is poor in the lazy eye then laser correction cannot help. Also see AMBLYOPIA.
LENS EXCHANGE WITH ASTIGMATIC IMPLANTS
Clear Lens Exchange can correct an unlimited range of prescriptions, including up to 5.00 dioptres of astigmatism. To correct an astigmatic prescription, the eye surgeon uses a specialist astigmatic lens, either fixed focus for distance or multifocal, to give good reading and distance vision.
Disease that causes dysfunction of the macula, the area of the retina responsible for central vision needed for such everyday activities as reading, driving, recognising faces and colours. The condition is commonly known as age-related macular degeneration (ARMD), and is the leading cause of visual impairment among older people. Macular degeneration causes blurred/distorted vision or a blind spot in the centre of the visual field. Peripheral vision is generally not affected. There is drug therapy available to treat certain forms of the disease but unfortunately not for all. Laser reye surgery is not a cure for ARMD.
Vision using one eye for distance and the other eye for clear reading vision. Presbyopic patients may find monovision a distinct advantage in that they do not need glasses at all. We recommend patients try this first in the form of contact lenses or glasses to ensure adaptation.
MYOPIA (SHORT SIGHT)
Close objects are clear but the ability to focus on objects at a distance is impaired. This is either caused by a steep cornea or the length of the eye ball being longer than normal which leads to the image being focused in front of the retina, producing a blurry image.
A specialist lens implanted during the Clear Lens Exchange procedure that provides good distance and reading vision. If the intraocular lens used during the procedure is not multifocal, the patient will still achieve excellent distance vision but will require reading glasses to focus less than an arm’s length away.
MULTIFOCAL CONTACT LENSES
Multifocal or progressive contact lenses allow you to see clearly for both near and far distances and are designed to remove the need for reading glasses for presbyopic patients. In general, one eye is slightly more biased towards seeing clearly for the distance than the other.