A full ocular examination is carried out to ascertain the potential vision of the eyes.  In particular, conditions such as dry eyes, glaucoma and macular disease need to be detected and managed prior to the operation. Scans and measurements of various parts of the eye are made and calculations are carried out to determine the power and type of lens to be used.

The risks and benefits of the operation for each patient will be discussed. We will ask about your general health and usual medications. We will discuss your visual needs and refractive planning, that is the choice or intra-ocular lens and types and power.

Insertion of the new lens gives the surgeon the opportunity to correct refractive errors that were present prior to the surgery. There is currently no artificial lens which can vary its focus from far to near.

The standard type of artificial lens has a fixed focus, in which case glasses are often needed to adjust the focus for different distances, typically for reading.

The need for glasses can be lessened by using different focal powers for the two eyes or by the use of multifocal intraocular lenses.

Each strategy has advantages and disadvantages. We will discuss this with you prior to the surgery.

The following is a more detailed guide, but we will guide you through the decision process at the pre-op consultation.

Part of the examination involves measurement of astigmatism. A small degree of astigmatism is part of the normal state of an eye and can be left uncorrected.

Pros

• Very sharp distance vision without glasses
• Good binocular balance
• Very sharp vision with multifocal glasses
• Very sharp reading vision with reading glasses
• Good driving vision without glasses

Cons

• Poorer depth perception without glasses
• Able to see the exit signs in the supermarket, but not the labels on groceries without glasses
• May have difficulty seeing dashboard display while driving even though distance vision is good

Pros

• Typically, the patient has good general-purpose vision without glasses
• Good distance and reading vision (general-purpose vision) in many patients without glasses. About 30% of patients do not use glasses often.
• Glasses still give excellent, very sharp all-round vision
• No glare and haloes at night

Cons

• Not very good depth perception without glasses
• Really need distance and reading glasses or multifocal glasses for best clarity and binocular depth perception

Pros

• good distance and intermediate vision without glasses
• the imbalance between the eyes is better tolerated
• good ‘supermarket’ vision
• good general-purpose vision without glasses
• good option for nursing home patients

Cons

• Reading glasses may still be needed

Pros

• Best near vision for people who read a lot who want to be spectacle free for reading
• Excellent near depth perception
• Good option for patients with a convergent squint
• Excellent binocular distant vision when using glasses
• No glare or halos at night if glasses are worn to drive

Cons

• Need glasses for distance

Pros

• Excellent distant and intermediate vision without glasses
• Minimal glare and haloes at night
• Excellent depth perception

Cons

• Reading glasses often still needed
• Slightly more expensive than conventional intraocular lenses

Pros

• The best chance of spectacle independence, although spectacles can sometimes be needed to refine the vision
• Best binocular depth perception
• Very good overall vision
• Well tolerated with modern lens designs
• Best results if implanted binocularly
• A good option for nursing home patients

Cons

• More likely to give glare and haloes at night, although these are more often an observation than interfering with vision
• In some patients, glasses may be needed part-time
• Occasionally, there may be a need for a second procedure to achieve independence from glasses
• The lenses are more expensive, although this is offset to an extent by the decreased need for spectacle
• Not currently accepted in Australia by CASA, although many overseas pilots overseas have multifocal intraocular lenses and fly without difficulties