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I have heard many of my colleagues discuss difficult conversations with contact lens wearing patients regarding refractive surgery. Often these patients have already decided to pursue refractive surgery and may be presenting for an examination prior to the refractive procedure. The difficult conversation, with perhaps ethical considerations, occurs when the clinician conducting the examination realizes that there is a very fixable problem with the patient’s contact lenses—and this “problem” with the contact lenses is contributing to the decision to pursue refractive surgery. It is a difficult conversation, but one that needs to proceed to serve the best interests of the patient so that they can be fully informed regarding their decisions.
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Alcon introduced the Dailies AquaComfort Plus family of one-day contact lenses with the additions of toric and multifocal contact lenses to the portfolio.
Dailies AquaComfort Plus Toric lenses combine the same dual thin zone Precision Curve Lens Design of Focus Dailies Toric contact lenses with the Blink Activated Moisture of the Dailies AquaComfort Plus sphere contact lens. Dailies AquaComfort Plus Toric contact lenses are available in a greatly expanded parameter range with over 800 more parameters than Focus Dailies Toric contact lenses including three industry standard cylinder powers of -0.75, -1.25 and -1.75 diopters. There are ten total axes available at +/- 20 degrees of 90 and 180, in 10 degree steps. Scribe marks are found at 3 and 9 o’clock to ensure a precise fit and to measure rotation.
Dailies AquaComfort Plus Multifocal contact lenses combine the Precision Profile Design of Air Optix Aqua Multifocal contact lenses with the Blink-Activated Moisture of Dailies AquaComfort Plus sphere contact lens. Dailies AquaComfort Plus Multifocal contact lenses offer the parameters of the Air Optix Aqua Multifocal contact lens including three levels of ADD to allow fitting of advanced as well as emerging patients with presbyopia in a binocular fashion. The distance powers range from +6.00 to -10.00 in 0.25D steps. They are available in trial 5-lens packs as well as 30 and 90 packs.
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Hydrogel Vision Corporation, makers of H2O disposable soft contact lenses, has expanded their Icuity H2O product line with a 14.8 diameter lens – Icuity H2O LD.
Icuity H2O LD is the only large diameter disposable lens on the market.
The larger diameter acts as a problem solver for patients who would benefit from a larger lens. It also provides increased comfort for patients who experience lens awareness in the product they are currently wearing. The 14.8 diameter provides full coverage sitting under the lid so any interaction that could cause discomfort from the lens edge is gone.
Icutiy H2O LD is made with hioxifilcon A, a non-ionic ultra-hydrating material that retains 99% of its water content on the eye, even under extreme conditions. According to the company, all lens dimensions and oxygen permeability are present throughout the entire wearing time. Lens comfort, movement and fit are stable throughout the day. Icuity H2O LD lenses are available in an 8.6 base curve from -0.25 to -8.00.
Diagnostic fit sets of Icuity H2O LD are available directly through Hydrogel Vision and through any of their authorized distributors.
For more information about Hydrogel Vision and their full product line, call 1-877-336-2482 or visit www.hydrogelvision.com.
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The Dutch bi-annual contact lens meeting, NCC 2014, marked its 5th anniversary with a record attendance of 1577 participants from 16 countries, though 95% of registered participants were from Belgium and the Netherlands. Speakers from all over the world delivered the majority of lectures in English. The meeting consisted of three tracks of continuous lectures. Topics ranged from scleral lenses to corneal cross linking to myopia control with contact lenses, in addition to everyday contemporary issues in contact lens practice and how to improve soft lens fitting. This was also the first non-North American presentation of the Tear Film and Ocular Surface Society International Contact Lens Discomfort Workshop.
This year’s meeting featured a ‘speed-date’ session wherein participants could talk to the international renowned speakers, including Lyndon Jones, Philip Morgan, Jason Nichols, Nancy Keir, Brian Tompkins and José Manuel González-Méijome, in eye-to-eye, two-minute interactions.
NCC 2016 will be held March 13-14, 2016.
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The Contact Lens Society of America (CLSA) has selected the Center for Organizational Management (CFOM) as its new management services provider. CFOM is a subsidiary of the Joint Commission on Allied Health Personnel in Ophthalmology (JCAHPO). After an extensive search by its leadership, CLSA elected to strengthen its alliance and relationship with JCAHPO and other nonprofits in the eye care profession by moving its headquarters to St. Paul, Minnesota in February 2014.
According to their announcement, this new alliance is an important strategy for CLSA’s potential membership and program growth, as well as maximizing resources and efficiencies. A significant advantage to CLSA is that CFOM has well-established management experience and an understanding of the entire eye care team to ensure maximum member benefits and a seamless transition for our membership.
CLSA is committed to the education and scientific research of eye care professionals in the use of and improvement of contact lens fitting for the eye industry. With this alliance through CFOM, CLSA and JCAHPO will work to create the synergy needed to provide the best opportunities for success in the education of contact lens technology.
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Midday Fogging in Scleral Lens Patients
In last week’s editorial, http://www.cltoday.com/new/issue_031614.asp, we asked readers for
thoughts on midday fogging in scleral lens patients. Below we share some of the comments we received.
I have had some success reducing scleral lens midday fogging by decreasing the amount of lens vault (chamber depth) over the cornea. I also feel tear
quality may be compromised in some of these patients, so I often prescribe lid scrubs as an attempt to clean things up. I think it helps.
Thomas G. Quinn, OD, MS, FAAO
Athens, OH
In my opinion, blinking is a great part of the problem. People are just plain lazy and don't blink. Possibly, as I hinted in my article, Mini-Scleral Lens
Fitting and Problem Solving, in the March Contact Lens Spectrum, the world of scleral fitters is somewhat to blame by fixing the lenses firmly
onto the conjunctiva rather than just onto the conjunctiva to allow for a bit of wobbling when blinking. The two forces together should help to maintain
the slow flow of debris from under the lens and reduce the tendency to midday fog.
By blinking the outer surface also remains clean and freshly refractive.
Bezalel Schendowich, OD, FIACLE
Jerusalem, Israel
In my practice the problem of midday fogging with scleral lenses is very rare. My explanation for this is in the limbus. If the lens fits close (without
touch) in the limbal zone, we have no fogging and much less edema.
Imre Kovats
Baden, Switzerland
I have been fitting scleral lenses for the last 12 years. We started with the 23 mm designs and then gradually switched to 18-19 mm devices. As far as I
can remember the problem of midday fogging appeared to a much greater extent in the last few years, when we started with mini-scleral, and was almost
nonexistent with full scleral designs. I believe that the limbal contact (permanent or blink induced), which is frequently inevitable in such designs, may
provoke an inflammatory reaction with consecutive debris accumulation or simply cause increased mucin formation.
Boris Severinsky, MOptom, FBCLA
Jerusalem, Israel
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OCULAR SURFACE UPDATE
Katherine M. Mastrota,
MS, OD, FAAO
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Incomplete Blinking
Riolan's muscle, clinically observed as the gray line of the lid margin, in synchrony with the obicularis muscle (and the blink) is involved in the
delivery of meibum from the meibomian glands. The following case study lends support to the importance of effective blinking behavior for a functional
lipid layer in the tear film.
A 38-year-old woman reporting foreign body sensations in her eyes was examined. The cornea was clear and tear secretion was normal. Lid margin
abnormalities were not observed and the meibum was clear. However, the lipid layer was very thin, and the patient was given a diagnosis of incomplete
blinking. The patient was made aware of her truncated blink and was advised to blink consciously and completely. An immediate increase in lipid flow was
observed following the patient's improved blinking pattern.
The authors conclude that tear lipid layer deficiency can occur with incomplete blinking even though meibomian gland structures are intact. This case
highlights the importance of complete blinking.
Kawashima M1, Tsubota K. Tear lipid layer deficiency associated with incomplete blinking: a case report. BMC Ophthalmol. 2013 Jul 16;13:34. doi:
10.1186/1471-2415-13-34.
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Try It Before You Buy It
Most of us would think twice about purchasing a car without first taking a test drive. Similarly, our professional recommendations carry more weight if they are grounded in our own personal experience. As a contact lens wearer, I always look forward to trying out new lenses and solutions.
I enjoy reading the package labeling and placing myself in my patients’ shoes, using the product as they would. This offers me tremendous insight into the benefits and limitations of the new technology, as well as into what my patients are experiencing. I also listen to my industry sales representative’s presentation, as that is another good method of gleaning new information. But nothing takes the place of hands-on experience. I consider it an extremely helpful aspect of practice, and I would recommend it to anyone.
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Modelling the Evaporation of a Tear Film Over a Contact Lens
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A contact lens (CL) separates the tear film into a pre-lens tear film (PrLTF), the fluid layer between the CL and the outside environment, and a post-lens tear film (PoLTF), the fluid layer between the CL and the cornea.
The authors examined a model for evaporation of a PrLTF on a modern permeable CL allowing fluid transfer between the PrLTF and the PoLTF. Evaporation depletes the PrLTF, and continued evaporation causes depletion of the PoLTF via fluid loss through the CL. Governing equations include Navier-Stokes, heat and Darcy's equations for the fluid flow and heat transfer in the PrLTF and porous layer. The PoLTF is modelled by a fixed pressure condition on the posterior surface of the CL.
The original model was simplified using lubrication theory for the PrLTF and CL applied to a sagittal plane through the eye. The researchers obtained a partial differential equation (PDE) for the PrLTF thickness that is first-order in time and fourth-order in space. This model incorporated evaporation, conjoining pressure effects in the PrLTF, capillarity and heat transfer. For a planar film, the authors found that this PDE can be reduced to an ordinary differential equation (ODE) that can be solved analytically or numerically. This reduced model allows for interpretation of the various system parameters and captures most of the basic physics contained in the model. Comparisons of ODE and PDE models, including estimates for the loss of fluid through the lens due to evaporation, are given.
Talbott K, Xu A, Anderson DM, Seshaiyer P. Modelling the evaporation of a tear film over a contact lens. Math Med Biol. 2014 Feb 11. [Epub ahead of print]
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A Proud Supporter of
Important Links:
To report adverse contact lens reactions visit:
http://www.accessdata.fda.gov/scripts/medwatch/ or call (800) FDA-1088.
To report possible grievances related to the Fairness to Contact Lens Consumers
Act or associated Contact Lens Rule visit:
https://www.ftccomplaintassistant.gov/.
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