Summer is upon us, which brings with it thoughts of sunshine, high heat and plenty of beach time. This raises some important reminders for us as it relates to contact lens wearers. First, it is critical to discuss swimming and contact lenses with your patients reminding them that generally contact lenses should not be worn during swimming activities (but a daily disposable thrown away after swimming is an option). Second, it is critical to discuss options for protection from ultraviolet radiation (UVR) exposures—whether it be with appropriate sunglasses or with contact lens options that have UVR blocking abilities. Make sure your patients know of all their options so that can fully experience these next few sunny months!
Jason J. Nichols, OD, MPH, PhD
Blanchard Adds New Feature to Onefit Scleral Lens Platform
Blanchard Contact Lenses announced that they have added a new feature, called XLC, to their ever-growing Onefit Scleral Lens Platform. XLC, which stands for Extra Limbal Clearance, is a new option that will make the existing trial set of standard 14.9mm lenses even easier to work with, by providing a simple solution for obtaining the extra limbal clearance needed, without increasing the lens diameter.
Prior to the release of the XLC option, practitioners ordering Onefit scleral lenses, may have had an optimal lens diameter with the 14.9mm standard Onefit lens – but when more limbal clearance was needed, they needed to go to the 15.2mm lens. Blanchard developed the XLC option, to ensure that the lens diameter, central clearance, power, and the landing on the sclera do not change, while offering more limbal clearance due to steeper mid-peripheral curves (or reverse curves). According to the company, the decision will be simple: If the diameter of the lens is ideal (3.0mm larger than HVID), while limbal clearance is not, they will use XLC to create more limbal clearance.
Plan now to attend the 11th Global Specialty Lens Symposium to be held January 19-22, 2017 at Rio in Las Vegas, Nevada. This meeting will include insightful presentations by international experts in the field, hands-on demonstrations of cutting-edge products and valuable continuing education credits.
Applications for Third Annual ABB Cares Program Accepted Starting August 1
ABB Optical Group will begin accepting applications for its third annual ABB Cares program on Monday, August 1. ABB Cares is open to eyecare professionals who want to nominate an outstanding non-profit organization in their community. ABB Optical Group will award an ABB Cares Platinum grant of $5,000, two Gold grants of $2,500 each, and four Silver grants of $1,000.
Organizations do not need to focus on eye health to qualify. To be considered as a grant recipient, all candidates must comply with the following:
The organization must be a 501(c)(3) organization and must be able to provide proof of this status.
The organization's local office must be within 30 miles of the nominating practice's primary location.
Applications must be completed and submitted online.
The deadline to submit an application is 11:59 p.m. EDT on August 31.
Orbis unveiled their new Flying Eye Hospital at Los Angeles International Airport. More than six years in the making, the third-generation Flying Eye Hospital is the world's only mobile ophthalmic teaching hospital on board an MD-10 aircraft. Hundreds of experts have come together to combine the latest in avionics, hospital engineering, technology and clinical expertise to make the new Flying Eye Hospital a reality. It features a modular design, 3D technology and live broadcast capabilities enabling Orbis, with their expert Volunteer Faculty, to train more doctors, more nurses and healthcare professionals—ultimately treating more people and restoring their sight.
The MD-10 aircraft housing the new Flying Eye Hospital has been donated to Orbis by longtime aviation sponsor, FedEx, and has been custom designed to bring the best of medical technology and training to the developing world. It is equipped with everything the Orbis medical team needs to provide hands-on training to local eye care professionals and convey the know-how to save and restore sight for patients in their own countries. The Orbis medical focus ranges from cataract to refractive errors, diabetes-related conditions, glaucoma, strabismus and more.
The plane boasts new 3D filming and broadcast capabilities so that participants in the classroom can experience and learn from live surgeries with a view similar to the surgeon's microscope lens. The Cybersight telemedicine platform then provides partner doctors free continuing medical education and mentorship from anywhere in the world, with availability to connect on difficult cases, share real-time diagnoses, and more.
From 2011-2015, Orbis work has facilitated 10,000 trainings of doctors, 104,000 trainings of nurses, biomedical engineers and other health care workers, and 11.6 million screenings and eye exams either on the Flying Eye Hospital or at Orbis in-country partner hospitals.
OCULAR SURFACE UPDATE Katherine M. Mastrota, MS, OD, FAAO
Filtering Blebs and Dry Eye
As eye care providers, we are sensitive to the effects of topical glaucoma agents on the ocular surface. But how does the presence of a glaucoma filtering bleb affect dry eye patients? A recent study evaluated dry eye disease in patients with mature, functioning filtering blebs and analyzed the associations between the morphology of filtering blebs and ocular surface changes.1 Filtering blebs were characterized by the Wuerzburg bleb classification scoring criteria (Wuerzburg bleb classification scoring criteria includes five items: vascularization, corkscrew vessels, encapsulation, microcysts and bleb height).
The patients with functioning blebs presented higher corneal staining scores and lower TBUT values than the control group. More patients in the study group complained of dryness, a gritty or sandy sensation and redness. The values for microcysts and bleb heights were significantly higher in the DED group. Bleb microcysts were positively correlated with corneal staining. Bleb height was negatively correlated with TBUT and positively correlated with corneal staining.
This study demonstrated that dry eye is relatively common in patients with functioning filtering blebs following trabeculectomy. Microcysts and bleb height are associated with ocular surface instability and dry eye disease.
The authors suggest that the ocular surface and the morphology of filtering blebs should be routinely evaluated in postoperative patients.
Ji H, Zhu Y, Zhang Y, Li Z, Ge J, Zhuo Y. Dry Eye Disease in Patients with Functioning Filtering Blebs after Trabeculectomy. PLoS One. 2016 Mar 31;11(3):e0152696. doi: 10.1371/journal.pone.0152696. eCollection 2016.
Just Hold on a Minute … Vaulting the Cornea Does Not Necessarily Mean It’s Not Influenced by Scleral Lenses.
A significant shift in prescribing patterns for gas permeable contact lenses has occurred over the past number of years with significant growth in the number of patients being fit into scleral contact lenses. The advantages proposed in the fitting of scleral lenses include improved comfort over corneal GP lenses, similar optical performance and the ability to fit highly irregular corneas since these lenses are intended to vault the entire cornea and land on the bulbar conjunctiva overlying the sclera. With vaulting most practitioners assume that influence of the lens mechanically on the cornea is dramatically minimized. However, a recently published study suggests that corneal shape and optical performance can in fact be significantly influenced following mini-scleral contact lens wear.
Researchers examined the influence of modern mini-scleral contact lenses, which land entirely on the sclera and overlying tissues, upon anterior corneal curvature and optics. Anterior corneal topography and elevation data were acquired using Scheimpflug imaging (www.pentacam.com) immediately prior to and following 8 hours of mini-scleral contact lens wear in 15 young healthy adults (mean age 22 ± 3 years, eight East Asian, seven Caucasian) with normal corneas. Corneal diurnal variations were accounted for using data collected on a dedicated measurement day without contact lens wear. Corneal clearance was quantified using an optical coherence tomographer (RS-3000, www.nidek.com) following lens insertion and after 8 hours of lens wear.
Results reported by the researchers indicated that although corneal clearance was maintained throughout the 8-hour lens wear period, significant corneal flattening was observed, primarily in the superior mid-peripheral cornea, which resulted in a slight increase in against-the-rule corneal astigmatism (mean +0.02/-0.15 × 94 for an 8 mm diameter). Higher order aberration terms of horizontal coma, vertical coma and spherical aberration all underwent significant changes for an 8 mm corneal diameter (p ≤ 0.01), which typically resulted in a decrease in RMS error values (mean change in total higher order RMS -0.035 ± 0.046 μm for an 8 mm diameter). There was no association between the magnitude of change in central or mid-peripheral corneal clearance during lens wear and the observed changes in corneal curvature (p > 0.05). However, East Asian participants displayed a significantly greater reduction in corneal clearance (p = 0.04) and greater superior-nasal corneal flattening compared to Caucasians (p = 0.048).
The authors concluded that mini-scleral contact lenses that vault the cornea induce significant changes in anterior corneal surface topography and higher order aberrations following 8 hours of lens wear. The region of greatest corneal flattening was observed in the superior-nasal mid-periphery, more so in East Asian participants. They suggested that practitioners should be aware that corneal measurements obtained following mini-scleral lens removal may mask underlying corneal steepening.
These results should be kept in mind as we are fitting more and more patients in scleral contact lenses for both irregular cornea cases as well as some patients with normal corneas. Also of note is the fact that specific scleral lens designs are also now being developed that address the racial differences in our patients. Specifically a new design of scleral lens has come to market with specific intent to be utilized more effectively on Asian eyes.
Vincent SJ, Alonso-Caneiro D, Collins MJ. Miniscleral lens wear influences corneal curvature and optics. Ophthalmic Physiol Opt. 2016 Mar;36(2):100-11.
Effect of Overnight Orthokeratology on Conjunctival Goblet Cells
The researchers’ objective was to evaluate the differences between goblet cell density (GCD) and symptomatology after one month of orthokeratology lens wear.
A pilot, short-term study was conducted. Twenty-two subjects (29.7±7.0 years old) participated voluntarily in the study. Subjects were divided into two groups: habitual silicone hydrogel contact lens wearers (SiHCLW) and new contact lens wearers (NCLW). Schirmer test, tear break up time (TBUT), Ocular Surface Disease Index (OSDI) questionnaire and conjunctival impression cytology, GCD, mucin cloud height (MCH) and cell layer thickness (CLT) were measured. All measurements were performed before orthokeratology fitting and one month after fitting to assess the evolution of the changes throughout this time.
No differences in tear volume and TBUT between groups were found (p>0.05). However, the OSDI score was statistically better after one month of orthokeratology lens wear than the baseline for the SiHCLW group (p=0.03). Regarding the goblet cell analysis, no differences were found in CLT and MCH from the baseline visit to the one month visit for the SiHCLW compared with NCLW groups (p>0.05). At baseline, the GCD in the SiHCLW group were statistically lower than NCLW group (p<0.001). There was a significant increase in GCD after orthokeratology fitting from 121±140cell/mm2 to 254±130cell/mm2 (p<0.001) in the SiHCLW group.
Orthokeratology improves the dry eye subject symptoms and GCD after one month of wearing in SiHCLW. These results suggest that orthokeratology could be considered a good alternative for silicone hydrogel contact lens discomfort and dryness.
Carracedo G, Martin-Gil A, Fonseca B, Pintor J. Effect of overnight orthokeratology on conjunctival goblet cells. Cont Lens Anterior Eye. 2016 Apr 13. pii: S1367-0484(16)30018-2. doi: 10.1016/j.clae.2016.04.001. [Epub ahead of print]