Dynamic Vision

Presbyopia occurs when the eye’s natural crystalline lens hardens with age, gradually losing its flexibility and ability to focus (its accommodation). This is largely dependent on the flexible lens being able to change shape and has a particular impact on the ability to focus on close objects, such as when reading. Most people will have presbyopia by the age of 45, requiring glasses or lenses to see clearly and read.

Dynamic Vision is a new vision correction technology, capable of providing visual rehabilitation to the over 1 billion people worldwide with presbyopia. There is currently no successful therapeutic, surgical treatment or cure for this condition. technology_colm

The Dynamic Vision project is developing a clear gel-lens system that will replace the old presbyopic lens. The lens is removed during a simple procedure and replaced by the polymer gel. Existing technology doesn’t restore the eye’s natural ability to focus. Ex-vivo testing has so far indicated that accommodation restored by the Dynamic Vision technology closely replicates that of the natural eye.

Currently, over 1 billion people have presbyopia and with the world’s population ageing at an extraordinary rate the potential market for such a product is enormous. In 2002, in the US alone, 123 million people (44 % of the population) were presbyopic.

The major competitive advantage of the Dynamic Vision technology is its unmatched ability to exceed accommodation requirements for comfortable reading. The hardening of the eye’s lens that occurs with age means the ability of the eye to focus is significantly restricted. This is particularly important during activities that require the eye to focus on close objects. Without this ability, objects are blurry and unclear, usually meaning the need for reading glasses.

The ‘mechanical’ accommodating intra-ocular lenses (IOL) currently under development have shown limited accommodative power – around 1 to 1.5D. In contrast, tests have shown that Dynamic Vision is capable of accommodative amplitude of up to 8.5D in ex vivo tests with human eye-banks and up to 12D in in vivo tests with primates. This is comparable to the focusing ability of someone in their early twenties.

The Dynamic Vision technology can be suitably launched onto the market as an alternative for lens replacement in cataract surgery procedures, during which the opaque lens is removed and replaced by a synthetic IOL. Cataracts are the leading cause of blindness in the world. Americans spend $6.8 billion per year on treatments for cataracts. There are currently 22 million Americans aged 40 and over with cataracts, estimated to reach 30 million by the year 2020.

With a growing world population that is ageing in many countries, presbyopia and cataract correction presents a huge market for the Dynamic Vision products. An estimated 25 % of this group may potential benefit from having Dynamic Vision gel once the technology is proven.

The Dynamic Vision technology is now being commercialised by the company Adventus Technology.

Technology Innovation

Until recently, conventional lens testing machines used to evaluate lens material have proven to be unsuitable because of the softness of the gels and the unique environmental conditions required to measure the physical properties.

As part of the Dynamic Vision project the Technology group has developed a new tensile and compression testing machine to accurately measure the soft polymer gel properties. The optical transmission characteristics of the same materials were determined in our optical laboratory by using an experimental set-up on the lab bench.

Investigators

Project Leader

Dr Paul Ericson

Key Personnel

Prof Arthur Ho
Dr Klaus Ehrmann

Collaborators

The Dynamic Vision collaboration, coordinated through the Vision CRC, has brought together world experts in ophthalmology, optics, accommodation, polymer chemistry and clinical research.

About Presbyopia

Presbyopia means ‘old sight’. When we read or look at something close, the flexible lens of the eye changes shape to provide the close focus required. However, as we age, the lens becomes less flexible and its ability to change shape is reduced.

This inevitable loss of flexibility is called presbyopia and causes near vision to be blurred.

Presbyopia is a natural part of ageing and a gradual process that usually noticeable by around 40 years of age. As a result, almost everyone over the age of 45 needs vision correction for reading and other close work.
Presbyopia is the most widespread ocular problem in the world. In 2010 approximately 44% of the Australian population were in the presbyopic age bracket, meaning almost 10 million people were affected.
It can be corrected with reading spectacles, bifocal or multifocal spectacles, and sometimes contact lenses.

Research by the Institute in the area of presbyopia includes: