As noted by the Quick Poll this month, practitioners remain enthusiastic about fitting scleral lenses, particularly in patients who have irregular corneas. As noted in other materials, the number one reason for fitting scleral lenses continues to be for conditions associated with an irregular cornea (e.g., keratoconus). We look forward to bringing you high-level content on these topics throughout the year, but encourage you to read our Annual Report on the latest trends in the field in the January issue of Contact Lens Spectrum.
Jason J. Nichols, OD, MPH, PhD
CooperVision Expands Parameters for Avaira Vitality Toric
CooperVision, Inc. has announced the nationwide availability of expanded parameters for its Avaira Vitality toric two-week contact lenses, which now include plus powers, high minus powers, and a –2.25D cylinder. The company has begun an initial rollout, and the full range will be available to all eyecare professionals in the United States in January 2018.
Made from a new silicone hydrogel material (fanfilcon A), Avaira Vitality toric delivers the best of Avaira toric with a higher water content (55%) and high level of oxygen permeability and transmissibility, according to the company. UV protection has also been improved to Class I, which means the lenses now block more than 90% of UVA and 99% of UVB rays, according to CooperVision.
With the expansion to the full range, Avaira Vitality toric is available in a power range of +8.00D to –10.00D with cylinder options of –0.75D, –1.25D, –1.75D, and –2.25D in axes from 10° to 180° in 10° steps. The lenses have a modulus of 0.6MPa, a Dk of 90, and a Dk/t of 90. The base curve is 8.5mm, and the diameter is 14.5mm.
American Academy of Optometry Call for Papers, Award Nominations, and Abstracts
The Lectures and Workshops Committee of the American Academy of Optometry invites the submission of up to three course proposals for consideration for Academy 2018 in San Antonio, TX, which will take place Nov. 7 to 10. Submission is between Jan. 2 to 31, 2018. Visit the Call for Courses webpage at www.aaopt.org/annual-meeting/san-antonio-2018/academy2017-courses.
In addition, each year the Academy honors individuals who have made significant contributions to vision science, education, and service to the profession and humanity. Nominations must be received from an Academy Fellow, with an explanation of why the nominee is particularly deserving of the award for which the nomination has been made. A letter seconding the nomination must come from another Academy Fellow. These documents, as well as a CV of the nominee, should be emailed to Helen Viksnins at HelenV@aaoptom.org prior to Apr. 1, 2018. For more information and a list of Academy Awards, visit the Awards page at www.aaopt.org/awards-and-grants/for-optometrists-and-vision-scientists.
Finally, the Academy’s Scientific Program offers scientists, educators, and clinicians the opportunity to exchange the latest information in optometry and vision science in two formats: research paper presentations and scientific posters. Visit the Scientific Program webpage at www.aaopt.org/annual-meeting/san-antonio-2018/meetings-academy2018-sciprog for more information or to download resources on how to construct your Scientific Program abstract. Please note that you do not need to be an Academy member to participate.
Eye Drop Pamphlet Available for Practitioners
To assist eyecare professionals and other healthcare professionals in helping consumers better understand when and how to properly use over-the-counter eye drops, The Mentholatum Company, distributors of Rohto Dry-Aid, in conjunction with the Intrepid Eye Society and CEDARS/ASPENS (Cornea, External Disease, and Refractive Surgery/American Society of Progressive Enterprising Surgeons), a not-for-profit society of anterior segment surgeon educators, has developed a new educational resource, Before You Buy Eye Drops: What You Need to Know. The resource offers important information about different types of eye drops and what they are most commonly used for, helpful “Do’s and Don’ts” to follow when using eye drops, step-by-step instructions on how to properly instill eye drops, and links to additional eye health information resources. Copies can be downloaded from the Resources section at the Rohto Dry-Aid Professional website at www.rohtoeyedrops.com/wp-content/uploads/2017/12/Before-You-Buy-Eye-Drops-What-You-Need-to-Know.pdf.
Heart of America Eye Care Congress to be Held in February
The Heart of America Eye Care Congress (formerly the Heart of America Contact Lens Society Contact Lens and Primary Care Congress) will hold its 57th annual meeting from Feb. 9 to 11, 2018, at the Sheraton Kansas City Hotel at Crown Center in Kansas City, MO. More than 60 CE hours will be available. Contact Dr. Ron Fiegel for registration information: 3460 N. Ridge Road, Ste. 140, Wichita, KS 67205; (316) 729-8900; e-mail email@example.com; or visit the organization’s website at www.hoaecc.org.
Student Develops Polarized Contact Lenses
University of Canterbury (UC) student Logan Williams has invented 3D-printed polarized contact lenses, providing sufferers of photosensitive epilepsy—in which flashing light can cause epileptic seizure—with a tool to overcome the threat of the condition.
Mr. Williams says he was inspired by the lack of non-medical prevention available to address the condition with the special lenses that he calls Polar Optics. Environmental threats include strobe lighting, but also such situations as walking past a line of trees that cast shadows with a flashing effect. The polarized contact lenses help through a process of refraction, according to Mr. Williams.
In his fourth year of a Master of Science degree in Applied Psychology at UC, Mr. Williams is in the process of commercializing Polar Optics with the aim of making the lenses accessible and affordable for those affected by photosensitive epilepsy.
BCLA to Hold Multiple Events Around the Globe in 2018
The British Contact Lens Association (BCLA) is going global in 2018 with a series of events aimed at providing eyecare professionals with the latest insight into best practice and state-of-the-art technology. BCLA UK returns in 2018 and, for the first time, will take place over two days across two cities—at The IET in Savoy Place, London, and at Conference Aston at Aston University, Birmingham. Provisional dates are June 4 and 10, featuring lectures, workshops and an exhibition, plus the return of the popular “Optical Assistant Courses” hosted by Sarah Morgan. The inaugural BCLA Asia conference held in 2016 will also return in 2018, this time in Singapore on Sept. 2-3. Visit www.bcla.org.uk.
When working with a patient who has an irregular cornea, which GP lens design are you more likely to use?
Sotiris Plainis, MSc, PhD, Heraklion, Crete
This image shows a keratoconic eye of 3.80mm radius of curvature, probably one of the steepest (but still healthy) corneas I have ever encountered. The 67-year-old patient had been wearing a 25mm PMMA scleral (haptic) lens for more than four decades. However, after all of these years of wear, he has been experiencing extensive lens “deposits,” limiting his wearing time to three to four hours per day and decreasing his visual acuity due to veiling glare and blur. We fitted this eye with a corneo-scleral contact lens (Rose K2 XL, Menicon SAS) that had a 14.60mm diameter, a 6.00mm base curve, a power of –15.75D, and a closed edge lift (–0.50D). His decimal visual acuity in this eye with the lens is now 0.8, and he can wear his lens for more than 14 hours per day.
We thank Dr. Plainis for this image and 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 a detailed explanation of the photo and your full name, degree or title, and city/state/country.
S. Barry Eiden, OD
Contact Lenses Are Not All the Same!
Today, there are so many soft contact lens options available—variables are quite numerous in terms of design and material properties. However, there is an opinion floating out there that “all soft contact lenses are the same.” Although manufacturers have taken the science of contact lenses to the point at which a single contact lens design with perhaps only one base curve and diameter is able to successfully “fit” a vast majority of corneal shapes, there are undoubtedly significant differences between these lenses. Variables that influence oxygen transmission, surface lubricity and coefficient of friction, dehydration rates, and lens stiffness, among others, can have a significant impact on clinical performance.
A recently published article evaluated the mechanical properties of commonly available soft contact lens materials and compared results using a custom-built MicroTensometer.1 In the study, the Young modulus, parameters for stress relaxation, and toughness of 18 types of single-vision soft contact lenses were measured. Results indicated that the 1-Day Acuvue Moist (Johnson & Johnson Vision [J&J]) and SofLens Daily Disposable (Bausch + Lomb) lenses measured the lowest moduli, whereas Air Optix Night & Day Aqua (Alcon) and Premio (Menicon) measured the highest. The measured moduli for silicone hydrogel materials were generally higher compared with the hydrogels except for Dailies AquaComfort Plus (Alcon). The toughness results showed that Dailies AquaComfort Plus is strong but not necessarily tough.
The researchers concluded from their study that the mechanical properties of commonly prescribed soft contact lens materials were able to be measured using a dedicated instrument. Its reliability was demonstrated, and modulus results were compared against published data from manufacturers and other research groups. Agreement was generally good, with only a few exceptions exceeding 15% difference. The more recently released silicone hydrogel lens types have reduced modulus, approaching that of medium- or high-water-content hydrogel materials.
Although this study concentrated on the mechanical properties of a variety of commercially available soft contact lenses, surely others have evaluated and compared other lens properties. Successful contact lens practitioners know how to utilize the various lens properties to maximize clinical success. Additionally, these property and performance differences highlight the fact that one lens type cannot and should not be substituted for another arbitrarily. There are forces in the contact lens industry that are trying to promote this activity based on false claims of equivalence. This behavior has the potential for significant negative outcomes and should be prohibited.
1. Kim E, Saha M, Ehrmann K. Mechanical Properties of Contact Lens Materials. Eye Contact Lens. 2017 Nov 7. [Epub ahead of print]
OCULAR SURFACE UPDATE
Katherine M. Mastrota, MS, OD
Another Piece to the Dry Eye Puzzle
We know that diabetes is a risk factor for dry eye,1 but did you know that there are many skin pathologies related to diabetes, including dry skin? I did not.
The American Academy of Dermatology lists the following diabetes-related skin disorders:2
Necrobiosis lipodica – Yellow, reddish, or brown patches on the skin that often begins as small raised solid bumps that look like pimples.
Acanthosis nigricans – A dark patch (or band) of velvety skin on the back of the neck, armpit, groin, or elsewhere.
Digital sclerosis – Hard, thickening skin on the hands, fingers, or toes (can develop elsewhere).
Bullosis diabetricorum – skin blisters.
Diabetic skin ulcers
Diabetic dermopathy – Brown spots (and sometimes lines) that create a barely noticeable depression in the skin that form on the shins or other areas of the body.
Eruptive xanthomatosis – Small, reddish-yellow bumps on the buttocks, thighs, crooks of the elbows, or backs of the knees.
Granuloma annulare – bumps and patches of small lesions that may be skin-colored, red, pink, or bluish purple.
Xanthelasma Papilloma (skin tags) – These growths are most common on the eyelids, neck, armpit, and groin.
Extremely dry, itchy skin.
I usually ask my patients about any skin conditions that they may have, generally looking for an allergy/atopy connection. I now have another reason to ask this question. Consider adding this probing query to your clinical history not only as clue to your dry eye diagnosis, but also as a clue to undiagnosed diabetic disease.
1. Zhang X, Zhao L, Deng S, Sun X, Wang N. Dry Eye Syndrome in Patients with Diabetes Mellitus: Prevalence, Etiology, and Clinical Characteristics. J Ophthalmol. 2016;2016:8201053.
2. American Academy of Dermatology. Diabetes: 12 warning signs that appear on your skin. Available at https://www.aad.org/public/diseases/other-conditions/diabetes-warning-signs. Accessed on Dec. 9, 2017.
Effect of Orthokeratology on Myopia Progression: Twelve-Year Results of a Retrospective Cohort Study
Several studies have reported the efficacy of orthokeratology for myopia control, yet most have follow-up periods shorter than three years. This study aimed to examine whether overnight orthokeratology influences the progression of manifest refractive error and safety of myopic children in a longer follow-up period (up to 12 years). If changes in progression rate were found, the study also aimed investigate the relation between refractive changes and different baseline factors, including refraction error, wearing age, and lens replacement frequency.
This is a retrospective study of 66 school-aged children who received overnight orthokeratology correction between January 1998 and December 2013. Thirty-six subjects, whose baseline age and refractive error matched with those in the orthokeratology group, were selected to form the control group. Subjects were followed up for at least 12 months. Manifest refractions, cycloplegic refractions, uncorrected and best-corrected visual acuities, power vector of astigmatism, corneal curvature, and lens replacement frequency were obtained for analysis.
Data of 203 eyes were derived from 66 orthokeratology subjects (31 males and 35 females) and 36 control subjects (22 males and 14 females) in this study. The duration of time they have worn the lenses ranged from seven years to 16 years (mean ± SE, 11.72 ± 0.18 years). The follow-up time ranged from one year to 13 years (mean ± SE, 6.32 ± 0.15 years). At baseline, their myopia ranged from –0.50D to –8.00D (mean ± SE, –3.70D ± 0.12D), and astigmatism ranged from 0.00D to –3.00D (mean ± SE, –0.55D ± 0.05D). Compared to the control group, the orthokeratology group had a significantly lower trend of refractive error change during the follow-up periods (p < 0.001). According to the analysis results of the GEE model, greater power of astigmatism was found to be associated with increased change of refractive error during follow-up years.
The authors found that overnight orthokeratology was effective in slowing myopia progression over a 12-year follow-up period and demonstrated a clinically acceptable safety profile. Further, an initial higher astigmatism power was found to be associated with increased change of refractive error during follow-up years.
Lee YC, Wang JH, Chiu CJ. Effect of Orthokeratology on myopia progression: twelve-year results of a retrospective cohort study. BMC Ophthalmol. 2017 Dec 8;17(1):243.