In The News
- In a paper presented at ARVO 2013, the Mayo Clinic’s Sanjay Patel, MD, and colleagues compared changes in the corneal endothelium after three different keratoplasty techniques. Studying outcomes after penetrating keratoplasty,
deep lamellar endothelial keratoplasty and Descemet-stripping
endothelial keratoplasty, they found that, after three years, cell loss
was less with the Descemet-stripping procedure.
GP Specialists rebranded its entire custom made-to-order soft contact lens product line with the name iSight. This includes the designs acquired through its purchase of American BioCurve in 2011. The company says it now offers “one of the largest portfolios of made-to-order products in the industry.”
- The World Council of Optometry (WCO) presented to Brien Holden, PhD its highest honor, the Distinguished Service Award,
which recognizes optometrists who have made an outstanding contribution
to the achievement of WCO’s mission to create a world where high
quality eye health and vision care is accessible to all.
Dr. Holden is the founder of the Brien Holden Vision Institute, a worldwide multidisciplinary research center and public health organization focused on developing breakthroughs in eye care that can improve the quality of vision for people who suffer from ocular disease. Through Dr. Holden’s efforts, the Institute has invested more than $450 million in the delivery of eye care to people in need over the last 20 years.
Cassini corneal diagnostic device
- TrueVision 3D Surgical and i-Optics announced a collaboration that will integrate the latter’s Cassini corneal diagnostic device with the former’s Refractive Cataract Toolset surgical guidance system. Removing a step in the presurgical cataract work-up can enhance speed and efficiency, they say, and blending the technologies will help to optimize patient workflow.
Doing the Keratoconus Two-Step
Keratoconus patients might have better refractive outcomes if they undergo a new two-step surgical approach, Medscape reports.
According to a small study presented last month at the American Society of Cataract & Refractive Surgery annual meeting, a protocol that pairs small-incision lenticule extraction (SMILE) with collagen crosslinking stabilized irregular corneas for an average of nine months.
A
protocol that pairs small-incision lenticule extraction (SMILE) with
collagen crosslinking could help keratoconus patients, like the one
pictured above.
And, significantly, mean uncorrected visual acuity in the seven study eyes improved from a baseline of 20/400 to 20/25 at nine months postoperatively. The work was done at the Instituto de Oftalmología Conde de Valenciana in Mexico City.
“The crosslinking is very good for halting progression, but refractively, it doesn’t bring much to the patient,” coauthor Gabriela Pagano, MD, told Medscape Medical News. With the combination procedure, “we’re bringing patients the possibility of spectacle independence.” The work was selected as Best Paper of the 2013 Refractive Surgery Session.
The SMILE procedure for keratoconus uses a femtosecond laser to cut a lenticule of tissue from the stroma, which is removed through a self-sealing incision. The pocket created is then infused with riboflavin and the crosslinking procedure proceeds.
Because the combined procedure preserves the integrity of Bowman’s layer—one of the major contributors to corneal strength—“this should be better than other corneal refractive procedures,” Dr. Pagano told Medscape. Pain is minimal and the risk for infection is lower by keeping the corneal epithelium intact, she added.
Lens Wear So Comfortable Patients Don’t Even Notice
In a 74-subject study of patients newly fit with 1-Day Acuvue TruEye (narafilcon A) lenses, contact lens wear was found to have no clinically significant effect on the ocular surface as compared to non-lens wearers across five of six contact lens-related measures associated with eye health, Vistakon research shows. The lens was also shown to provide high levels of comfort from morning to night, comparable to wearing no lenses at all, according to the company. The findings were published recently in Contact Lens & Anterior Eye.
Comfort scores assessed at the six study visits were equivalent for contact lens wearers and patients who had not previously worn contact lenses and remained with spectacle wear for 12 months.
After a full year of wear, there were no clinically significant differences between contact lens and spectacle wearers for bulbar conjunctival hyperemia, limbal hyperemia, corneal staining, neovascularization and papillary conjunctivitis. There was more low-grade “trace” conjunctival staining for contact lens wearers than spectacle wearers.
An Early Look at the Performance of a New Lens
While the US launch of Alcon’s new Dailies Total 1 daily disposable is anticipated later this year, research on the delefilcon A material’s performance is starting to appear.
A meta-analysis of clinical data presented at ARVO 2013 documented an association between lubricity profile, measured by coefficient of friction, and subjective reports of comfort in three assessments: upon initial insertion, overall comfort and end-of-day comfort.
Each of the three outcomes showed a highly significant association between the respective comfort measure and coefficient of friction, according to the ARVO abstract (494/B0131).
Encouraging Data on Myopia Control
A new contact lens design shows noteworthy potential for decreasing myopic progression, based on animal study results published in Investigative Ophthalmology & Visual Science.
The purpose of the randomized, masked study was to determine the effect of wearing a new lens with a unique optical design on the development and progression of defocus-induced myopia in newly hatched chickens. According to the study, the lens caused a significant reduction in the development of defocus-induced myopia over a 14-day wearing period, compared to a control lens identical in every aspect except optical design.
There was also a significant axial length difference, with the control group showing increased ocular axial growth as compared to the test design groups.
The lens is being developed by Visioneering Technologies of Alpharetta, Ga. Research was conducted by the Centre for Contact Lens Research at the University of Waterloo’s School of Optometry & Vision Science in Canada.
This study is the first to report “nearly complete inhibition of defocus-induced myopia in chickens compared to control lenses,” said lead author Jill Woods, MCOptom. The lack of significant axial length increase seen “indicates that these lens designs reduced defocused-induced myopia progression through the inhibition of axial elongation.” Although further work is needed to determine the exact mechanisms by which the lens decreases myopia development, the potential was significant, she added.
Visioneering Technologies says its contact lens technology has multiple applications, including control of myopic progression as well as multifocal vision correction for presbyopia. The company expects to introduce a contact lens for presbyopia incorporating its unique technology in early 2014.
An intraocular lens using the company’s technology for presbyopia is also under development.
Woods J, Guthrie SE, Keir N, et al. “Inhibition of defocus-induced myopia in chickens.” Invest Ophthalmol Vis Sci. 2013 Apr 12; 54(4):2662-8.
