multifocal contact lenses

1. UNDERSTANDING MULTIFOCAL CONTACT LENS
 Multifocal lenses are options for people who want to transition from bifocal
or multifocal glasses to contact lenses.
 These types of contact lenses are great for people with active lifestyles who
do not want to be chained to their reading glasses.
 There are different types of multifocal lenses available on the market that
correct different types of vision disorders.

2. DIFFERENT TYPES OF MULTIFOCAL CONTACT LENSES
• Soft Lenses:
Best for use on a part-time basis, soft lenses are a good choice because they
are the easiest for the eye to adjust to.
• Gas Permeable Lenses:
Gas permeable lenses have been known to give better results, but they do
require some adaptation for the wearer. Gas permeable (GP lenses) should be worn
every day in order for your eyes to condition to them.
• Hybrid Multifocal Lens:
For those who want the best of both worlds, there is now a hybrid multifocal
lens available that is soft around the peripheral with a gas permeable center –
making this lens easier to wear with great vision results.
These are two of the different types of bifocal pattern lenses for bifocal and
multifocal lenses.
 Simultaneous Design
 Alternating image design

3. • Simultaneous Design:
Puts the near and far portions of the lens in front of the pupil at the same
time, which makes the brain have to determine which parts of the lens to use to get
the best image resolution.
• Alternating image design:
This is the most similar to the bifocal and multifocal glasses currently
available and uses the bottom portion of the lens for the near vision and the top
portion of the lens for the distance vision. The two parts of the alternating lens is
separated by an almost invisible line that your eye care provider uses to determine
if the lens is fitting properly.
TRANSLATING
In this translating design the near power is on the bottom. The bottom edge is
flattened to keep the lens from rotating on your eye when you blink.
Advantages
 Sharp near / far vision
 When it works well , it is very successful
 Works better in RGP and less successful in SCL
Disadvantages
 Takes longer in adaptation
 Comfort is less due to thick design
 Dependence on eye-lens relation ship

4. BLENDED / SIMULTANIUS VISION
This design is a little more uncommon, but provides the wearer with a more
precise viewing experience.
It typically places the distance and near prescriptions closer to the center of the
eye, but corrects specific points of abnormally in the eyes, mimicking a natural
viewing experience.
Simultaneous contact lens design
 Diffractive
 Aspheric
 Translating
Concentric Bifocal Pattern Lens:
This is the most commonly used lens for bifocal and multifocal lenses. With
a concentric bifocal pattern contact lens, the near correction is located in a small
circle at the center of the lens and is surrounded by a larger circle that contains the
distance correction. This can be flip-flopped where the distance correction is in the
center and the near correction is in the outer ring.
DIFFRACTIVE
This design is the most common design for multifocal contacts. It generally
consists of a set of concentric circles that harbor different lens powers, often
prescribed for different viewing distances

5. ASPHERIC DESIGNS
It formed with alteration of anterior and posterior curvature of the lens
Advantages
 No ghosting as in concentric design
 Clarity of vision at all distances
 Simplified fitting
 Used mostly for office workers
Disadvantages
 Pupil dependency
TWO TYPES OF ASPHERIC DESIGN
 ASPHERIC BACK SURFACE LENS DESIGN
 ASPHERIC FRONT SURFACE LENS DESIGN
ASPHERIC BACK SURFACE LENS DESIGN
 Fit well over aspheric cornea
 Has aspheric posterior curve
 Increasing plus power peripherally
 Provide central distance correction

6. ASPHERIC FRONT SURFACE LENS DESIGN
 Aspheric anterior curve
 Back surface is spherical
 Increasing plus power centrally
 Provide central near correction
Advantages of multifocal
 Better visual acuity for the range of distances from near to far
 A less abrupt switch between prescriptions
 The ability to see in most conditions without extra eyewear

7. Drawbacks of multifocal
Multifocal contact lenses offer a lot of performance ability, but may also
be:
• More difficult to adjust to due to a different viewing experience
• Accompanied by nighttime glare and hazy or shadowy vision during the
adjustment period
• More expensive because of the increased complexity in design
MULTIFOCAL CONTACT LENS ALTERNATIVES
If multifocals don’t sound like they’re a good fit, there are a number of other
options, including:
• Pairing reading glasses with normal contact lenses
• Monovision contact lenses
• Bifocal contact lenses
• Surgical correction or lens implantation recommended by your doctor
MODIFIED MONOVISION
 This is a technique where one eye is fitted with distance correction and the
other eye is a bifocal lens

8. UNSUCCESSFUL CL FITTING
 High myopes
 Patients with busy schedules
 Dry eyes
 Flat corneas
 Laxity of lower lid
 High astigmatism