In our 2014 Annual Report on contact lenses, published in the January 2015 edition of Contact Lens Spectrum, we found that 24% of over 500 U.S. respondents said that they regularly practice myopia control with contact lenses in their patients. I was astonished by this figure, thinking it would be much lower than that. This is true even though we don’t have an FDA cleared contact lens intended for this purpose, and it is very important that the regulatory agencies make a clear path for industry to follow in seeking such clearances for such products as they may significantly slow the progression of myopia in our patients.
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Optometry experts from across the United States and Canada convened in Dallas, Texas, on December 11–13, 2014, for the inaugural Dry Eye Summit. Over 70
leaders in dry eye disease gathered to discuss the state of dry eye disease diagnosis and management in optometry, and what can be done to improve how
local optometrists address this condition. Seventeen companies in the field of optometry and dry eye disease jointly sponsored the Summit.
Several expert groups in the U.S. and Canada have developed dry eye disease guidelines, but their complexity has made it challenging for community ECPs to
implement strategies for managing dry eye disease in their practices. The goal of the Summit was to address this unmet need and make a substantial impact
in the quality and consistency of care of dry eye patients at the community level by creating easy-to-use dry eye disease recommendations.
Over the two days of the meeting, the expert attendees discussed concise, effective recommendations for identifying and managing patients with dry eye
disease. The Panelists were able to identify key areas of agreement and create straightforward, easy-to-implement recommendations in the areas of
screening, diagnosis, and treatment.
The Summit participants plan to disseminate the insights from the Summit in a set of expert recommendations, as well as numerous publications and other
communications throughout 2015.
Dry Eye Summit Co-Chairs were: Marc Bloomenstein, OD, FAAO, Schwartz Laser Eye Center, Scottsdale, Arizona; Derek Cunningham, OD, FAAO, Dell Laser
Consultants, Austin, Texas; Ian Benjamin Gaddie, OD, FAAO, Gaddie Eye Centers, Louisville, Kentucky; Paul Karpecki, OD, FAAO, Koffler Vision Group,
Lexington, Kentucky; Scot Morris, OD, FAAO, Eye Consultants of Colorado, Conifer, Colorado; and Kelly Nichols, OD, MPH, PhD, FAAO, University of Alabama at
Birmingham, Birmingham, Alabama.
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Join us January 22 - 25, 2015 for Global Specialty Lens Symposium at Bally’s Hotel & Casino in Las Vegas. The GSLS is a comprehensive meeting focusing
on the latest techniques and technologies for the successful management of ocular conditions using today's specialty contact lenses. The meeting includes
information for vision care professionals in all disciplines, with both surgical and non-surgical options covered. Accredited for continuing education
under COPE, NCLE, and JCAHPO, the meeting will offer approximately 30 credit hours.
Attended annually by more than 500 participants from 30+ countries it is the largest conference of its kind in the U.S.
For complete conference details and to register now, visit GSLSymposium.com.
--ADVERTISING
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CooperVision, Inc. announced that through the creative fundraising efforts of its employees around the globe, $115,000 has been donated to Optometry Giving
Sight in support of the 2014 World Sight Day Challenge. The company is an Optometry Giving Sight Global Gold Sponsor.
Employees at more than 25 locations organized and participated in local activities to generate the funds, including a 5K walk/run, t-shirt sale, jeans
days, raffles and World Sight Day Challenge bracelet sales. The Cooper Companies matched employee donations.
In addition to its employee-led donations to the World Sight Day Challenge, CooperVision generates additional funds year-round for the organization through
industry initiatives. These include offering contact lens patients the opportunity to donate eligible rebates to the cause, which itself has produced more
than $200,000 in funding.
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This is a post epi-off crosslinking case in which the patient unusually developed a corneal haze and irregular central cornea. The irregularity is currently
managed with a scleral lens which improved VA from 20/100 (spectacle prescription) to a 20/25+ (scleral lens). The lens provided a safe, therapeutical
space.
We thank Dr. Ibanez for this image and we welcome photo submissions from our other readers! It is easy to submit a photo for consideration for publishing
in Contact Lenses Today. Simply visit http://www.cltoday.com/upload/upload.aspx to upload
your image. Please include an explanation of the photo and your full name, degree or title and city/state/country.
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OCULAR SURFACE UPDATE
Katherine M. Mastrota, MS, OD, FAAO
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The 2014 Word of the Year
I consider myself to possess a fairly expansive vocabulary. I subscribe to Miriam-Webster’s “Word-of- the- Day”. I attempt to commit to memory a new word
every day. I research words I am not familiar with. Therefore you can understand why I was thoroughly disappointed in myself when I was stumped at meaning
of the word that Oxford Dictionaries’ lexicographers selected as the “2014 Word of the Year”.
“Vape”…that’s the winning word. Defined by the Oxford Dictionary, the verb form of “vape” means ‘to inhale and exhale the vapor produced by an
electronic cigarette or similar device", while the device itself (noun) can also be known as a vape. Vape is also the modifier for other nouns, creating
new compound nouns. The most common of these are vape pen and vape shop, and there is also recent evidence for vape lounge, vape fluid, vape juice, and
others..1
An electronic cigarette (e-cig or e-cigarette) or electronic nicotine delivery system (ENDS) is a battery-powered vaporizer that simulates tobacco smoking.
E-cigarettes and vape pens are similar devices but are so called because of the specific vaporizing materials they are associated with: e-cigarettes are
marketed specifically for “e-juices” that usually contain nicotine and can function and mimic the look and feel of real cigarette. On the other hand, pen
vaporizers, are usually associated with a wide range of vaping materials. Tantalizingly, nicotine or non-nicotine containing e-juices can be flavored with
an endless array of flavors, for example, Lemon Bars, Cherry Lime-Aid, Waffles with Butter and Syrup, Mojito, even German Chocolate Cake. These products
are currently unregulated by the Food and Drug Administration.
Tobacco smoking, as we all are aware, is detrimental to overall health and is associated with ocular surface disease. What about the use of electronic
cigarettes that have become popular? Electronic cigarettes do not contain tobacco, although they do use nicotine from tobacco plants. They do not generate
cigarette smoke but rather an aerosol (an aerosol is a suspension of fine particles of liquid, solid or both in a gas: both the particulate and gas phases
are mixtures of chemical substances in e-cigarette aerosols2) that is frequently but inaccurately referred to as vapor (a vapor is a substance
in the gas phase).
E-cigarettes represent a $1.7 billion industry (in 2013).3 They are readily available for purchase in convenience stores, smoke shops, mall
kiosks, supermarkets or even online (traditional cigarettes shipments are regulated). Rates of e-cig use in teens rose from 4.7% in 2011 to 10% in 2012.4 A recent Pediatrics study of 1900 young high-schoolers in Hawaii shows 29% have tried e-cigarettes.5 There is cause
for concern for this alarming increase in teenage use of e-cigs. Said CDC Director Tom Frieden, MD, MPH, "Nicotine is a highly addictive drug. Many teens
who start with e-cigarettes may be condemned to struggling with a lifelong addiction to nicotine and conventional cigarettes." “About 90 percent of all
smokers begin smoking as teenagers,” said Tim McAfee, MD, MPH, director of the CDC Office on Smoking and Health, emphasizing the gravity of this public
health issue.
Environmental concerns and issues regarding non-user exposure exist. The health impact of e-cigarettes, for users and the public, cannot be determined with
currently available data.6
Scientific evidence regarding the human health effects of e-cigarettes is limited. While e-cigarette aerosol may contain fewer toxicants than cigarette
smoke, studies evaluating whether e-cigarettes are less harmful than cigarettes are inconclusive.
A PubMed “e-cigarette dry eye/ocular surface” search on 12/08/2014 yielded no results. I eagerly studies on this topic and until then suspect that the use
of ENDS negatively impact the ocular surface environment. I am certain I will revisit this critical issue in the
months to come.
1. Accessed 12/29/2014.
http://blog.oxforddictionaries.com/2014/11/oxford-dictionaries-word-year-vape/
2. Tianrong Cheng. Chemical evaluation of electronic cigarettes. Tob Control. May 2014; 23(Suppl 2): ii11–ii17.
3. Accessed 12/29/2014. http://www.cnbc.com/id/100991511#.
4.Accessed 12/29/2014. http://www.cdc.gov/media/releases/2013/p0905-ecigarette-use.html
5. Wills TA, Knight R, Williams RJ, Pagano I, Sargent JD. Risk Factors for Exclusive E-Cigarette Use and Dual E-Cigarette Use and Tobacco Use in
Adolescents. Pediatrics. 2014 Dec 15. pii: peds.2014-0760. [Epub ahead of print]
6. Callahan-Lyon P. Electronic cigarettes: human health effects. Tob Control. 2014 May;23 Suppl 2:ii36-40.
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Hold on now…Don’t forget about oxygen transmission with Hybrid and Scleral contact lenses.
Great interest has been demonstrated towards the application of both hybrid and scleral GP contact lenses for the management of patients with both regular
and irregular corneas. Advantages of these lens modalities include both lens wearing comfort and optimization of vision quality. However, attention must
always be given to the potential physiological responses to these types of contact lenses. Two studies recently were published that explored tear film
oxygen tensions at the corneal surface beneath new design hybrid contact lenses as well as scleral contact lenses.
In the first study theoretical oxygen tensions at the corneal surface, if tear mixing and exchange are excluded, were calculated for hybrid CL designs
(modern, high oxygen-permeable rigid center) with a single chamber corneal model using a computer software spreadsheet. Hybrid CL tear vaults were measured
by both slitlamp biomicroscopy and optical coherence tomography (OCT). Results indicated that by using all measurements, excluding any potential
contributions from tear exchange or mixing, the authors predicted corneal surface tear pO2 values under several hybrid CLs to range from zero under a lens
with an excessive vault to corneal surface tear pO2 values of 112 mm Hg under a lens with a minimal vault. The authors stated that tear vaults beneath the
gas permeable portion of the hybrid CLs of 100 μm or less resulted in acceptable corneal surface oxygen values. Conversely, in situations where tear vaults
are greater than about 100 μm, they predicted that anterior corneal surface pO2 values are less likely to be adequate for optimal corneal physiology. Any
significant tear exchange, however, should increase these values. The authors cautioned that their measurements of tear thickness provided inconsistent
results, thus limiting the reliability of their primary results.1
The second study looked at tear layer oxygen tension levels beneath scleral contact lenses using the same method as the prior study. The authors found that
only in the best case scenario for current scleral gas permeable lenses considering lens thickness, material Dk and tear layer thickness values beneath the
lenses would allow for sufficient tear layer oxygen tension (approximately 100mmHg) to preclude corneal hypoxia. They suggested that clinicians would be
prudent to prescribe scleral GP lenses manufactured in the highest Dk materials available and to fit without excessive corneal clearance to minimize
anterior segment hypoxia.2
There is no doubt that with the introduction of new high Dk hybrid lenses and modern scleral GP lenses we are able to provide our patients with improved
contact lens wearing comfort along with the ability to optimize their visual outcomes. However, as is always the case in contact lens management we have to
provide 3 pillars of success: vision, comfort and appropriate physiological response. Due to the vaulting method of fitting both newer design hybrid and
scleral contact lenses we are creating a potential barrier to oxygen transmission. Careful attention needs to be given to issues such as the degree of
corneal vaulting, lens material Dk and, in the case of hybrid lenses, lens movement that all can assist in providing adequate oxygen to the cornea.
1.Lee KL, Nguyen DP, Edrington TB, Weissman BA. Calculated In Situ Tear Oxygen Tension Under Hybrid Contact Lenses. Eye Contact Lens. 2014 Dec 11.
[Epub ahead of print]
2. Jaynes JM, Edrington TB, Weissman BA. Predicting scleral GP lens entrapped tear layer oxygen tensions. Cont Lens Anterior Eye. 2014 Oct 13.
[Epub ahead of print]
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Antimicrobial Role of Human Meibomian Lipids at the Ocular Surface
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Human meibomian lipids form the outermost lipid layer of the tear film and serve many important functions to maintain its integrity. Although not
investigated earlier, these lipids may have antimicrobial properties that help in strengthening the innate host defense of tears at the ocular surface. The
aim of this study was to investigate the antimicrobial role of human meibomian lipids.
Ocular pathogenic bacteria, Staphylococcus aureus 31, Pseudomonas aeruginosa 19, Pseudomonas aeruginosa 20, and Serratia marcescens 35, were grown in the presence and absence of human meibomian lipids in an artificial tear solution at the physiological
temperature. Viable counts were obtained to note the number of bacteria surviving the treatment with meibomian lipids. Bacterial cells were imaged using
scanning electron microscopy to observe the damages caused by meibomian lipids.
Viable count results showed that in the presence of meibomian lipids, growth of all bacteria was considerably lower. Scanning electron microscopy showed
that meibomian lipids caused extensive cellular damage to bacteria as manifested in smaller size, loss of aggregation, abnormal phenotype, cellular
distortion, damaged cell wall, and cell lysis.
This is the first-ever report of the antimicrobial role of human meibomian lipids. The author concluded that these lipids possess antimicrobial properties
against both Gram-positive and Gram-negative bacteria and are involved in the innate host defense of tears in protecting the ocular surface against
microbial pathogens.
Mudgil P. Antimicrobial role of human meibomian lipids at the ocular surface. Invest Ophthalmol Vis Sci. 2014 Oct 14;55(11):7272-7.
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