Biocompatibility and Contact Lens Materials

by Joel Harrison 31. October 2011 10:34

Biocompatibility and Contact Lens Materials

Because of the fact that – in spite of the progress that has been made in the area of contact lenses materials – there are still a number of people who stop wearing contact lenses due to discomfort, researchers have started to place a great emphasis on the biocompatibility of polymers (of which modern contact lenses are made) with the eye.

According to Dr Roderick W.J. Bowers, an expert in the area of contact lens materials, biocompatibility is still not fully understood, despite decades of research. Contact lenses are recognised by the eye as a foreign body, and an appropriate response begins when a lens is inserted (certain biomolecules, such as lipids, proteins, immunoglobulins bind at the surface of the lens). In this respect, contact lenses resemble other medical devices, like stents or urinary catheters.

In Dr Bowers’s opinion, biomimetic materials (e.g. phosphorylcholine) will allow researchers to develop contact lens materials offering much better comfort thanks to their increased resistance to deposits.

 

Multifocal Contact Lenses for Patients with Irregular Corneas

by Joel Harrison 29. October 2011 10:24

Multifocal Contact Lenses for Patients with Irregular Corneas

According to Dr Ronald K. Watanabe, an eye care expert writing for Contact Lenses Today, the modern manufacturing technology allows companies to produce a wide variety of excellent GP contact lenses with designs suiting the needs of patients who have irregular corneas. In such patients, increasing visual acuity is the main goal and when the patient can see well, the goal is considered to be achieved.

In consequence, most practitioners do not think about multifocal contact lenses when treating presbyopic patients with irregular corneas, as this would make the problem too complicated. However, Dr Watanabe stresses, most companies specialising in GP lenses can now produce speciality lenses incorporating multifocal optics. For instance, Art Optical manufacturers SO2Clear Progressive multifocal contact lenses whose design is corneo-scleral.

These technologically advanced lenses are a great opportunity for elderly patients with irregular corneas, Dr Watanabe concludes, adding that new designs are being developed and should be available soon.

 

Poor Vision Results in Numerous Accidents

by Joel Harrison 27. October 2011 14:43

Poor Vision Results in Numerous Accidents

A report prepared by the Institute for Advanced Motoring (IAM) warns that poor vision is the cause of half as many accidents as using mobile phones while driving. The report is based on police data (including statistics regarding 700,000 car accidents that occurred from 2005 to 2009), which state that vision problems result in 0.4 per cent of all accidents that were related to distraction.

A project manager for the IAM, Neil Greig, stated that the numbers show that many popular convictions regarding safe driving are simply myths. According to him, most car crashes do not involve vehicles going at great speeds and out of control; they are connected with small mistakes that have serious consequences.


The conclusion that should be drawn from the report is that wearing one’s contact lenses (or glasses) while driving is absolutely necessary for reasons of safety. What is more, various experts argue that contact lenses are superior in this respect, as they offer a much wider field of vision and are much more reliable than glasses (they do not get dirty, shift unexpectedly, etc.).

 

New Procedure Designed to Restore Vision Tested

by Joel Harrison 25. October 2011 13:36

New Procedure Designed to Restore Vision Tested

Scientists have developed a new method of permanent vision correction. In the near future, everyone will be able to undergo a simple surgical procedure and then stop wearing contact lenses or glasses.

The procedure (referred to as ‘Z Kamra’) involves inserting a special plastic implant in the eye after a small incision is made in the cornea. The implant, which is smaller than a contact lens, is placed around the iris and the pupil, and acts like a pinhole camera, reducing the amount of light that reaches the retina to the beams that produce the clearest images. The beams that are on the outer range of vision (useful in dark light, but not producing clear images) are blocked, and the patient can enjoy perfect vision.

However, according to Dr Larry Benjamin, an eye surgeon, Z Kamra (which costs £2,800 per eye (£4,600 for two)) is not suitable for everyone and people of certain professions (e.g. pilots) will not be able to undergo it.

 

Expert: Technology Has Markedly Improved Contact Lenses

by Joel Harrison 23. October 2011 12:11

Expert: Technology Has Markedly Improved Contact Lenses

We have got so accustomed to how good modern contact lenses are that we tend to forget how much has changed in the technology of their manufacture and how it has affected their quality and the range of conditions they can be used to treat.

In a recent interview, Chidambara Pillai, who is the chair of the British Society for Refractive Surgery, pointed out that the quality of contact lenses currently available on the market has increased substantially due to technological progress. This, in the expert’s opinion, also includes contact lenses designed for individuals with rare conditions (especially those suffering from keratoconus and other illnesses associated with an irregular shape of the cornea, previously impossible to treat effectively).

The patients who would like a more permanent solution to their eye problems can use implantable contact lenses, the expert added. Such lenses, Pillai stated, do not affect the shape of the cornea and can treat a wide range of refractive errors.

 

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