Saturday 31 October 2015

People's Gait May Reveal Whether They Have Glaucoma

October 2014 — For people with glaucoma, walking isn't as easy as it once was. Even in the early stages of the disease, when vision hasn't yet deteriorated noticeably, glaucoma sufferers may walk more slowly, bump into things, stumble and sway.
Researchers at Washington State University School of Electrical Engineering and Computer Science have been using sensors in clinical trials to analyze people's gait. The trials are comparing the gaits of glaucoma patients with those of people in control groups.
The sensors are worn on special shoes and can detect the length and evenness of a step, as well as the equity between the feet. By detecting changes and abnormalities in the way a person walks, the analysis could provide an early indication of glaucoma's presence and could also prevent serious injury from falls.
The University of California, Los Angeles, is recruiting more participants in various stages of glaucoma for the next phase of the research.

Caution: Some Special-Effect Halloween Contact Lenses Reduce Vision Quality

October 2015 — Special-effect contact lenses (also called theatrical lenses, Halloween contact lenses, and decorative contacts) are a popular choice among costume enthusiasts who want to dramatically alter their appearance, especially at Halloween.
Halloween contact lenses can reduce vision quality.
But beware: According to a new study, some special-effect contacts can interfere with your vision, especially in low-light conditions such as when driving at night or walking after dark.
Researchers investigated changes in visual function of 30 healthy volunteers who wore either clear contact lenses or special-effect contacts with different pigment-free optical zone diameters (in other words, with different sizes of pupil openings in the design). Special-effect lens designs evaluated in the study had clear pupil zone diameters of 4.0, 5.0 and 6.0 millimeters, which are smaller than the natural pupil diameter of relatively young people in low-light conditions.
The study included visual acuity tests with a standard eye chart and measurements of contrast sensitivity and higher-order aberrations.
Results showed that participants who wore special-effect contact lenses with small pupil designs (4 mm clear pupil zone) had significantly reduced visual acuity. Also, higher-order aberrations increased with special-effect designs with small pupil zones, and contrast sensitivity decreased when wearing the decorative lenses (even in normal lighting).
The study authors concluded that people considering purchasing theatrical contact lenses for Halloween and other occasions should be made aware of possible disturbances in visual function these lenses may cause.
Remember, just like conventional (clear or nearly clear) contact lenses that are prescribed for nearsightedness or farsightedness, special-effect contacts must be fitted by an eye care provider, and a contact lens prescription is required to purchase them. Special-effect lenses are available with or without corrective power and therefore can be worn by nearly everyone — including people with naturally perfect vision — for fun and special occasions.

Friday 30 October 2015

GOC warns of health risk of Halloween Contact Lenses

The General Optical Council (GOC) has issued a warning to the public that they may be putting their sight at risk by using cosmetic contact lenses this Halloween.
Speaking to the magazine of the Chartered Trading Standards Institute, TS Today, which will be published in the November issue, the GOC warns that wearers are putting their eye health at risk by buying lenses from non-optical outlets, such as novelty shops or market stalls.
While zero powered, or plano, contact lenses are dealt with separately from powered contact lenses, the law states that they must be dispensed in the supervision of a registered optometrist, dispensing optician or medical practitioner.
The GOC’s director of strategy, Alistair Bridge, said: “Cosmetic contact lenses should not be supplied by anyone other than an optician or doctor. Opticians make sure that contact lenses fit properly and that wearers receive expert advice on how to wear and store them safely.”
He added: “They will also offer important advice such as not to sleep in contact lenses and to never share or swap lenses, which can spread eye disease.”
Chief executive of the Chartered Trading Standards Institute, Leon Livermore, said: “Cosmetic contact lenses are often made and distributed on a 'one size fits all' basis and not tailored to the wearer's needs which can increase the risk of eye health issues.”
Mr Livermore added: “To minimise these risks it is essential that cosmetic lenses are fitted by a qualified professional who is able to provide advice on their safe use and ongoing care. We would advise against buying products like these online, or from retailers, as without professional supervision, there are more likely to be health concerns for the individual.”
Anyone with information relating to outlets selling cosmetic contact lenses illegally can contact the GOC’s legal compliance department at or call 020 7307 3931.
Earlier this month the regulator concluded its consultation into strategies for tackling illegal practice, which includes the online sale of contact lenses.
The GOC aims to introduce a voluntary code of practice for online contact lens retailers, with retailers who sign up awarded a logo to help the public recognise them as a regulated supplier.
Under the proposals, those found in breach of the code would have their use of the logo revoked. However, details on what form any further action might take are yet to emerge.

Tuesday 20 October 2015

Zeiss Drivesafe Germany trip video

Matheson Optometrists discover Drivesafe lenses by Zeiss

Several members of the Matheson Optometrists team have recently returned from a trip to Germany to discover all about Zeiss Drivesafe lenses.

These staff members experienced a whole weekend driving cars and learning why Zeiss Drivesafe lenses provide motorists with more confidence and a greater all round motoring experience.

Many people feel insecure, uncomfortable and stressed when driving, especially in difficult light and weather conditions such as rain and mist, or at dusk or night. On average 83% of spectacle lens wearers also drive. Driving can be a real challenge for everybody – no matter how long the distance, and good vision is vital for safety.   

Luminance Design® Technology by ZEISS.The pupil reacts to light intensity from its surroundings, specifically the light that directly strikes the eye. In daylight conditions, the pupil diameter is small, whereas it is large at night. In low light, so-called mesopic conditions, i.e. twilight, rainfall, dark days or night driving, the pupil diameter is in-between small and large. Space perception, as well as distance assessment, becomes more difficult for the driver.

After intensive research in the field of mesopic vision*, the rationale for the development of ZEISS Luminance Design™ Technology was identified and verified during wearer trials. In a nutshell: there is bright light (photopic vision), no light (scotopic vision) and in-between low light (mesopic vision). In mesopic conditions, the light intensity, and thus the pupil size changes: a challenge for visual performance.


DuraVision® DriveSafe Coating by ZEISS.Glare describes the difficulty of seeing in bright light, such as direct sunlight or artificial light. Especially when driving at night, the high luminance from car headlights with Xenon or LED technology is distracting. Glare can be a risk, as it reduces the visibility of objects and sensitivity of the eye to contrast.

Advised by the automotive lighting experts at L-LAB* who provided state-of-the-art lighting equipment, ZEISS vision science researchers carried out glare experiments. These formed the basis of internal studies** using different coating simulations. The blue light spectrum of car headlights (in particular in the 400–450 nm range) using Xenon H.I.D. (High Intensity Discharge) or LED technology produces a glare effect perceived by drivers.

Accurate vision of road, dashboard and mirrors

Driving demands a high level of concentration from drivers. Most of the time they need a broad view of the road in order to evaluate traffic conditions. The situation becomes challenging, especially for progressive lens wearers, when they need to switch their focus between the road, dashboard and mirrors. That is when dynamic vision becomes essential.