International contact lens prescribing in 2010

For the past nine years, we have described the current state of contact lens fitting worldwide in Contact Lens Spectrum. This year, we report on 24,642 lens fits in 27 markets. As in all previous years, coordinators in each market distributed up to 1,000 paper or electronic survey forms to contact lens practitioners who, in turn, collected information about their next 10 fits. Data were processed and checked in the survey administrative offices in Manchester, United Kingdom and in Waterloo, Canada.

The changing face of contact lens wearers over 25 years

A combination of factors has dictated patterns of prescribing to contact lens wearers in different age groups over time, such as the evolution of manufacturing technology in bringing better lens designs and replacement frequency options; the aging population demographic; and the knowledge and attitudes of practitioners. Here we explore evolving lens fitting practices at the opposite poles of the age spectrum—children and presbyopes.

Trends in Australian contact lens prescribing 2011

The 12th annual survey of Australian contact lens prescribing was conducted between January and April 2011, employing the same format as in previous years. About 3,000 optometrist members of Optometrists Association Australia were sent an e-mail message with a link to a downloadable questionnaire, and a request that this be accessed, printed and completed to provide details of the first 10 patients fitted with contact lenses after receipt of the questionnaire.

International contact lens prescribing in 2011

This is the 11th annual report of contact lens prescribing trends that we have prepared for Contact Lens Spectrum. Each year, we capture current modes of contact lens practice by asking practitioners in each market (optometrists, opticians or ophthalmologists, as appropriate) to provide information about the first 10 lens fits undertaken after receiving our paper or electronic survey form. In 2011, we captured information about 22,362 fits in 29 countries.

Contact lens prescribing : USA vs the world

Along with other facets of commericialization, the contact lens market has become globalized during the past 30 years. The major international companies have worldwide distribution networks and supply lenses of the same product names and replacement frequencies to all nations, with a few minor adjustments for marketing and regulatory reasons. Small and medium-sized companies, often producing more specialized lenses, are also active in markets across the world.

Contact lens prescribing in Canada 2011

For the past 12 years, the International Contact Lens Prescribing Survey Consortium has sent surveys to a selection of Canadian optometrists in order to collect information on the contact lenses they fit and basic demographic data of the patients. Canada is one of about 40 countries that contributes to the global study and while annual reviews of the study data are presented, information published for any one market is limited due to the size of the dataset.1 This manuscript presents a more detailed analysis on the Canadian market for 2011.

Trends in contact lens prescribing 2012

The 13th annual survey of Australian contact lens prescribing was conducted between January and April 2012. The same format as in previous years was employed. About 3,000 members of Optometrists Association Australia were sent an e-mail message with a link to a downloadable questionnaire, and a request that this be accessed, printed and completed to provide details of the first 10 patients fitted with contact lenses after receipt of the questionnaire.

Contact Lens Complications [Third Edition]

"Contact Lens Complications has become established as the definitive guide to the ocular response to contact lens wear. In this highly anticipated third edition, award-winning contact lens author, clinician and researcher, Professor Nathan Efron, presents a thoroughly revised and expanded, clinician-friendly account of how to identify, understand and manage contact lens complications in modern-day practice. Professor Efron is renowned for his ability to distil often complex principles of ocular physiology and pathology into an easy-to-read, highly structured format. The subject matter is systematically laid out, with various complications arranged logically by tissue structure - which is the way practitioners naturally approach clinical problems. Beautifully presented and lavishly illustrated with full-colour schematic diagrams and clinical pictures, this book can serve as both a practical chair-side manual and authoritative reference."--publisher website

New technologies for assessing the contact lens wearing eye

New technologies for examination of the anterior eye in contact lens practice don’t appear to have taken a huge leap in the past decade however there a several novel adaptations of existing technology worthy of note. In other areas of health we have self-diagnosis via smartphone or other gadgets adapted as medical devices. In practice and research in vitro and in vivo new adaptive technologies have expanded our capabilities in assessing the anterior eye, in particular corneal and conjunctival confocal microscopy.

Detection and quantification of tear phospholipids and cholesterol in contact lens deposits : the effect of contact lens material and lens care solution

PURPOSE. To examine the deposition of tear phospholipids and cholesterol onto worn contact lenses and the effect of lens material and lens care solution. METHODS. Lipids were extracted from tears and worn contact lenses using 2:1 chloroform: Methanol and the extract washed with aqueous ammonium acetate, before analysis by electrospray ionization tandem mass spectrometry (ESI-MS/MS). RESULTS. Twenty-three molecular lipids from the sphingomyelin (SM) and phosphatidylcholine (PC) classes were detected in tears, with total concentrations of each class determined to be 5 ± 1 pmol/μL (~3.8 μg/mL) and 6 ± 1 pmol/μL (~ 4.6μg/mL), respectively. The profile of individual phospholipids in both of these classes was shown to be similar in contact lens deposits. Deposition of representative polar and nonpolar lipids were shown to be significantly higher on senofilcon A contact lenses, with ~59 ng/lens SM, 195 ng/lens PC, and 9.9 μg/lens cholesterol detected, whereas balafilcon A lens extracts contained ~19 ng/lens SM, 19 ng/lens PC, and 3.9 μg/lens cholesterol. Extracts from lenses disinfected and cleaned with two lens care solutions showed no significant differences in total PC and SM concentrations; however, a greater proportion of PC than SM was observed, compared with that in tears. CONCLUSIONS. Phospholipid deposits extracted from worn contact lenses show a molecular profile similar to that in tears. The concentration of representative polar and nonpolar lipids deposited onto contact lenses is significantly affected by lens composition. There is a differential efficacy in the removal of PC and SM with lens care solutions.