After spending hours of time working with the patient to get things just right, the contact lens prescription walks out the door. Or, you see a patient who swears they recently had an eye exam elsewhere and just need a quick prescription from you for –3.00D. Or, you have those patients who consistently complain of discomfort while wearing their contact lenses, but who don’t do any of the interventions you have prescribed to improve comfort.
Sound familiar? Unfortunately, I am sure it happens to you all the time. As Yogi Berra said, “If the world was perfect, it wouldn't be.“ Very true. Try and find a little humor in your day, every day, to help overcome the frustrations that might otherwise drive you or your staff mad.
Jason J. Nichols, OD, MPH, PhD
The American Optometric Association (AOA) announced the passing of Richard L. Wallingford Jr., OD, after battling cancer for more than a decade. Dr. Wallingford was the 84th president of the AOA, serving from 2005-2006. He was active in the Maine Optometric Association, on the New England College of Optometry board, and was former treasurer of the World Council of Optometry. He also had a private practice in Bangor, ME. He is known for his national advocacy efforts regarding patient access to optometric care.
He is survived by his wife Elaine, and their children and grandchildren.
GPLI Announces New Educational Resources
The GP Lens Institute (GPLI), the educational wing of the Contact Lens Manufacturers Association (CLMA), has added two new resources to its website.
The new Staff Training Module includes an 84-page document that provides a comprehensive overview on lens care as it pertains to corneal and scleral GP lenses, hybrids, and custom soft lenses. In addition, “how-to” videos on lensometry and the radiuscope are provided. A five-video staff-training module from GPLI Advisory Board member Roxanna Potter, OD, is also included in the module. The video covers areas such as contact lens care instruction, front desk reception training for contact lenses, pre-testing and checkout, and follow-up training. Links to 23 archived webinars on GP and custom soft lens design and care that would be helpful in educating staff members have also been provided. This module can be found at www.gpli.info/staff-training.
In conjunction with the Scleral Lens Education Society, the GPLI has also launched the Scleral Lens Troubleshooting FAQs module. This module consists of commonly asked practitioner questions about scleral lenses and answers from experts from the Scleral Lens Education Society, as well as GPLI advisory board members. Illustrated with 113 images, the information in this module serves as a resource for all practitioners currently fitting and troubleshooting scleral lenses, as well as those who are interested in learning how to do so. This module can be found at www.gpli.info/scleral-lenses.
AOCLE Reveals Healthy CL Habits Guide
The Association of Optometric Contact Lens Educators (AOCLE) has developed a series of “Healthy Habits” guides for soft, GP, and, the latest in this series, scleral lenses. AOCLE wanted to establish a standardized set of basic instructions, based on published literature, that educators, practitioners, residents, and students can use to educate novice contact lens users on how to properly take care or their contact lenses, as well as with patients who are non-compliant with instructions. The illustrated guides offer an overview of hand washing, care of contact lenses, cleaning and replacement of lens cases, no topping off solutions, and more.
With the growth in scleral lens fitting, a guide specific for that modality was need to address specific issues related to scleral lenses. Etty Bitton, OD, MSc, an associate professor at the Université de Montréal, along with optometry student, Michelle Zakem, spearheaded the “Healthy Scleral Lens Habits” guide. The guides are completely generic and are available in English, French, and Spanish. All of the guides are downloadable at aocle.org.
EyeCare Prime Introduces LensFerry S Gives Sight
In support of its ongoing commitment to helping provide basic eye care to underserved populations around the world, EyeCare Prime, a subsidiary of CooperVision, Inc., has partnered with Optometry Giving Sight to introduce its own philanthropic initiative, LensFerry S Gives Sight.
For each LensFerry S subscription, EyeCare Prime makes a donation to fund projects that provide access to vision care for people in need. To date, 5 million people around the world have benefitted thanks to projects funded by Optometry Giving Sight. And, in what will now become an annual commitment, the LensFerry S team spent five days in Oaxaca, Mexico, helping to provide eye exams and glasses to more than 1,500 students between the ages of five and 14 as part of the Our Children’s Vision campaign.
ABB Optical Group Releases Year in Review Industry Insights
Reviewing 2016 sales and projecting 2017 growth, ABB Optical Group released data on same-store sales that shows that daily disposable contact lens growth was up nearly 23% and represented 76% of all growth in the category in 2016. Reusable contact lenses were soft in 2016 with a slight decline of 0.4%, but have come to life with recent monthly lens introductions of sphericals, torics, and multifocals. The company also reported that growth of torics was up 11%, driven predominantly by daily disposable torics, which were up more than 36%. In addition, multifocals continue to post gains with growth of nearly 17%. The growth was dominated by daily disposable multifocals at more than 69% due to recent introductions from all four major manufacturers in this area. Looking at 2017, ABB Optical Group predicts that toric and multifocal lenses will continue to drive growth in the daily disposable category.
Visiometrics Launches New Website
Visiometrics has launched a newly designed website at www.Visiometrics.com, showcasing its ophthalmic diagnostic technology. The new site improves the customer experience with access to video and academic resources, user manuals, and patient education materials.
The new site makes it easier for providers and patients to find general product and technical information for Visiometrics’ HD Analyzer. The system’s visual quality measurements provide critical objective data for better patient outcomes in cataract surgery, dry eye treatment, and refractive surgery, according to the company.
On the new site, in-depth product information is supplemented with academic articles and video interviews with providers who use the system. An interactive quiz helps providers assess if they are good candidates to add an HD Analyzer to their practices. Finally, a dedicated patient page provides education materials to help providers explain the value of an HD Analyzer exam.
Alex Nixon, Columbus, OH
The image shows corneal epithelial bullae, resulting from mechanical interaction between the peripheral cornea and a 14.9mm scleral lens. Bullae–dark, pebble-like elevations–are pockets of epithelial edema developing after stretching of the corneal epithelial tight junctions. Hypothetical stretching occurs when force exerted on the scleral lens by the blink does not cause lens translation, instead applying pressure to the peripheral cornea in improperly fit scleral lenses. Bullae don’t occur in all cases of peripheral corneal bearing, but they were reported in six of 14 subjects wearing a small diameter scleral lens, according to a 2016 case series by myself and several colleagues (http://www.contactlensjournal.com/article/S1367-0484(16)30180-1/abstract).
We thank Alex Nixon 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
Boldly Go Where No One Has Gone Before!
Unconventional applications of contact lenses are being explored that will allow us to think about contact lenses in ways that have never before been considered. Two articles were recently published that describe some intriguing applications of contact lens technologies.
The first article describes developments in contact lenses for sustained drug delivery.1 The researchers developed a simple method to load drugs into commercially available contact lenses utilizing fluorous chemistry. They demonstrated this method using model compounds including fluorous-tagged fluorescein and the antibiotic ciprofloxacin.
They demonstrated that fluorous interactions facilitated the loading of model molecules into fluorocarbon-containing contact lenses, and that the release profiles exhibited sustained release. Contact lenses loaded with fluorous-tagged ciprofloxacin exhibited antimicrobial activity against Pseudomonas aeruginosa in vitro, while no cytotoxicity toward human corneal epithelial cells was observed. Significantly, the modified lenses also exhibited antimicrobial efficacy against Pseudomonas aeruginosa in an in vivo infection model. Overall, utilizing fluorous chemistry, they were able to construct a drug delivery system that exhibited high drug loading capacity, sustained drug release, and robust biological activity.
The second article described the development of technologies that enhanced the performance of “smart” contact lenses.2 Smart contact lenses with electronic circuits have been proposed for various sensor and display applications, where the use of flexible and biologically stable electrode materials is essential. Graphene is an atomically thin carbon material showing outstanding electrical and mechanical properties, as well as excellent biocompatibility. In addition, graphene is capable of protecting eyes from electromagnectic (EM) waves that may cause eye diseases such as cataracts.
The researchers report the graphene-based highly conducting contact lens platform reduces the exposure to EM waves and dehydration. The results showed that the EM energy is absorbed by graphene and dissipated in the form of thermal radiation so that the damage can be minimized. They demonstrated the enhanced dehydration protection effect of the graphene-coated lens by monitoring the change in water evaporation. The researchers concluded that the graphene-coated contact lens would provide a new healthcare and bionic platform for wearable technologies in the future.
Traditional use of contact lenses has been for the correction of ametropia. Further development of contact lens applications has allowed for their use in management of ocular surface disease, therapeutic treatment of corneal disease, and trauma, etc. Now, we are further expanding contact lens applications into drug delivery systems, monitoring of physiological functions (such as intraocular pressures and glucose levels), and information processing. Going forward, so-called smart contact lenses will be utilized for virtually limitless applications.
Stay tuned as we continue to go where no one has gone before. These are the voyages of the Starship Contact Lens!
1. Qin G, Zhu Z, Li S, McDermott AM, Cai C. Development of ciprofloxacin-loaded contact lenses using fluorous chemistry. Biomaterials. 2017 Jan 31;124:55-64.
2. Lee S, Jo I, Kang S, Jang B, Moon J, Park JB, Lee S, Rho S, Kim Y, Hong BH. Smart Contact Lenses with Graphene Coating for Electromagnetic Interference Shielding and Dehydration Protection. ACS Nano. 2017 Feb 21. [Epub ahead of print]
OCULAR SURFACE UPDATE
Katherine M. Mastrota, MS, OD
Noxious Stimuli Hit a Corneal Nerve
As we learn more about ocular discomfort/pain in ocular surface disease (OSD), we are discovering that non-obvious pathologic changes in the corneal nerves may be responsible for a chronic pain signal from the cornea. Emerging technologies that allow imaging of corneal nerves in vivo are spawning questions regarding the relationship between corneal nerve density, morphology, and function.
The cornea contains the highest density of nociceptive nerves (pain receptors that recognize and react to a stimulus) of any tissue in the body. These nerves are responsive to a variety of modalities of noxious stimuli and can signal pain even when activated by low threshold stimulation. Injury of corneal nerves can lead to altered nerve morphology, including neuropathic changes that can be associated with chronic pain (neuropathic pain).
In a 2017 study, researchers tested if noxious stimulation of the corneal surface altered nerve morphology and neurochemistry.1 In this study, menthol, capsaicin, and hypertonic saline were applied to the ocular surface of an awake rat. Animals were sacrificed and corneal nerves were examined using immunocytochemistry and three-dimensional volumetric analyses.
In their results, the authors showed that menthol and capsaicin both caused a significant reduction in corneal nerve density. Hypertonic saline did not reduce nerve density, but did cause qualitative changes in nerves including enlarged varicosities (swollen or tortuous) that were also seen following capsaicin and menthol stimulation. All three types of noxious stimuli caused a depletion of calcitonin gene-related peptide (CGRP) from corneal nerves; CGRP is an amino acid produced by neurons that binds to receptors that activate vasodilation, inflammation, and pain, and it has been implicated in migraine pathogenesis, indicating that all modalities of noxious stimuli evoked peptide release.1
The authors suggest that studies aimed at understanding the relationship between corneal nerve morphology and chronic disease may also need to consider the effects of acute stimulation on corneal nerve morphology. As clinicians, let us consider how menthol-containing eye drops and tear hyperosmolarity may impact corneal nerves and their contribution to the discomfort of patients with OSD.
1. Hegarty DM, Hermes SM, Yang K, Aicher SA. Select noxious stimuli induce changes on corneal nerve morphology. J Comp Neurol. 2017 Feb 18. [Epub ahead of print]
Post-Lens Tear Turbidity and Visual Quality After Scleral Lens Wear
The aim of this study was to evaluate the turbidity and thickness of the post-lens tear layer and its effect on visual quality in patients with keratoconus after the beginning of contact lens wear and before lens removal at the end of eight hours.
Twenty-six patients with keratoconus (aged 36.95 ± 8.95 years) participated voluntarily in the study. The sample was divided into two groups: patients with intrastromal corneal ring segments (ICRS group) and patients without ICRS (KC group). Distance visual acuity (VA), contrast sensitivity, pachymetry, post-lens tear layer height, and post-lens tear layer turbidity (percentage area occupied and number of particles per mm2 ) were evaluated with optical coherence tomography before and after wearing a scleral lens.
The researchers reported that a significant increase of turbidity was found in all groups assessed (p < 0.05). The number of particles per square millimeter was eight times higher after scleral lens wear than at the beginning of lens wear for all groups. In addition, VA decreased in all groups after scleral lens wear (p < 0.001). All patients showed a statistical diminishing of contrast sensitivity after scleral lens wear (p < 0.05). And, a significant correlation was found for both turbidity parameters with distance VA but no correlation between turbidity and post-lens tear layer thickness was found at the beginning (p > 0.05). The authors also found a strong correlation in all groups between the post-lens tear layer at the beginning and differences of tear layer thickness between two measures (p < 0.05).
The authors concluded that the decrease in VA while the subjects were wearing the scleral lenses, which were filled with preserved saline solution, was due to the increasing post-lens tear layer turbidity.
Carracedo G, Serramito-Blanco M, Martin-Gil A, Wang Z, Rodriguez-Pomar C, Pintor J. Post-lens tear turbidity and visual quality after scleral lens wear. Clin Exp Optom. 2017 Jan 26. [Epub ahead of print]