Optical correction

Abstract

The present disclosure describes compositions which improve visual acuity and to methods for their use.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]The present application claims the benefit of and priority to British Patent Application No. 0724558.2, filed in the United Kingdom on Dec. 15, 2007, the entire disclosure of which is incorporated herein by reference.BACKGROUND[0002]1. Technical Field[0003]The present invention relates to topical compositions to improve visual acuity and to methods for their use. More particularly, but not exclusively, it relates to eye-drops and the like to ameliorate the effects of presbyopia, myopia, hypermetropia. astigmatism and combinations thereof.[0004]2. Background of Related Art[0005]One prevalent form of visual defect is presbyopia, in which the lens of the eye becomes relatively rigid, particularly with age, so that it becomes increasingly difficult to focus. This leads to eyestrain, and ultimately to recession of the near point, such that a sufferer of presbyopia may be unable to read or work on objects at arm's length.[0006]The conventional r...

AI Technical Summary

Benefits of technology

[0018]In embodiments, a method for improving visual acuity is disclosed which includes administering a first active agent containing a parasympathetic agonist to an eye, and then administering a second active agent selected from the group consisting of a sympathetic antagonist, a sympathetic agonist, and combinations thereof.

Problems solved by technology

One prevalent form of visual defect is presbyopia, in which the lens of the eye becomes relatively rigid, particularly with age, so that it becomes increasingly difficult to focus.

This leads to eyestrain, and ultimately to recession of the near point, such that a sufferer of presbyopia may be unable to read or work on objects at arm's length.

However, since this will probably also move the wearer's far point closer, sacrificing their distance vision, reading glasses must usually be removed for driving, for example.

However, the field covered by the lenses may not be sufficient for all purposes.

Again, the restricted field covered by the “reading” portion of the lens may not be satisfactory, and many people cannot get used to bifocal lenses.

Bifocal lenses are usually more expensive than standard lenses.

Furthermore, many people dislike wearing any form of spectacles for reasons of comfort or for reasons of personal style.

Contact lenses have been proposed that are akin to bifocal spectacle lenses, but many people are uncomfortable with wearing contact lenses.

Many sufferers from presbyopia would not be prepared to risk (or pay for) corrective surgery.

There are thus drawbacks with each of the known approaches for improving a presbyope's ability to see nearby objects.

Myopia is a visual defect in which the cornea is too steeply curved, or the eyeball is too long, for light from significant distances to be focused on the retina, irrespective of the performance of the lens.

This leads to a near point a significant distance from the eye, and similar problems to those resulting from presbyopia.

However, the same drawbacks are also experienced.

Similar drawbacks are found in existing approaches to correcting various other minor refractive errors of the eye.

A further complication is that it is not uncommon to suffer from more than one vision defect; for example, a degree of astigmatism is often present for myopes and hypermetropes.