Optical Coherence Tomography (OCT) is not longer a tool just for the posterior segment. I have heard about OCT imaging applications of the anterior segment and wondered what research has been done with regards to contact lenses. Two very recent papers describe the use of OCT to measure tear meniscus volumes in contact lens wearers and to characterize the edge fitting of soft contact lenses.

Chen et all (Chen 2010) investigated the relationship between tear meniscus volumes and ocular discomfort during daily soft contact lens wear in symptomatic and asymptomatic wearers. Lenses were imaged multiple times points by OCT before and after a rewetting drop was instilled. Tear meniscus volumes were calculated based on meniscus areas and eyelid lengths. They were able to identify that the meniscus volumes decreased gradually during a 10-hour period and comfort ratings were linearly correlated with these tear meniscus volumes.

Shen et al (Shen 2011) used ultra-high resolution and ultra-long scan depth OCT to assess edge fitting and tear film gaps on patients while wearing various soft contact lenses with different edge designs. They were able to identify that "angle-edged lenses" had significantly less conjunctival buildup compared to "round-edged lenses." They were also able to image post-lens tear film gaps at the limbus and corneal mid-periphery which were present more frequently when "round-edged lenses" were worn.

Both of these studies demonstrate the application of these new technologies as promising methods to design new lenses, evaluate their fit, and view the tear layer to predict on-eye lens performance and comfort.

References:
Chen Q, Wang J, Shen M, Cui L, Cai C, Li M, Li K, Lu F. Tear menisci and ocular discomfort during daily contact lens wear in symptomatic wearers. Invest Ophthalmol Vis Sci. 2010 Nov 4. [Epub ahead of print]

Shen M, Cui L, Riley C, Wang MR, Wang J. Characterization of soft contact lens edge fitting using ultra-high resolution and ultra-long scan depth optical coherence tomography. Invest Ophthalmol Vis Sci. 2011 Mar 2. [Epub ahead of print]

Two columns ago, I began a discussion of comfort and how it relates to contact lens materials and designs. In that column, surface wettability was presented as a clinically useful parameter that contributes to comfort. Related to this but not discussed as much is friction of the contact lens surface. Friction is the resistance of a surface to motion, in this case the contact lens against the ocular and palpebral conjunctival surfaces. The lower the coefficient of friction, the more easily the lens will move across the ocular surface, and maybe more importantly, the more easily the upper eyelid will move across the lens surface on a blink. The coefficient of friction of a lens surface depends on surface smoothness, electrostatic surface charges, and the presence or absence of lubricants (Nichols, 2007).

Manufacturers strive to produce lenses with smooth, wettable, deposit resistant, slippery surfaces. Lens surface lubricity is further enhanced by lubricating agents found in lens care products as well as the natural components of the preocular tear film. Though data on friction of lens surfaces is hard to find and depends on numerous variables, newer technology, such as atomic force microscopy, that can better characterize the surface topography of lenses, will hopefully help the continued development of comfortable lenses.

Reference:
Nichols JJ. Considering the Facts of Friction. Contact Lens Spectrum. July 2007.

Allergan's Pyott Resumes Role as President

Allergan, Inc. announced that its Board of Directors has reappointed David E.I. Pyott as President. Mr. Pyott will also continue to serve Allergan in his current roles as Chairman of the Board and Chief Executive Officer. Mr. Pyott's role as President will be effective March 27, 2011, with the departure of F. Michael Ball, who has accepted the position of Chief Executive Officer of Hospira, Inc.

With Mr. Pyott expanding his role as President, the new organizational structure will allow for a seamless management transition and continuity in execution of Allergan's established strategies and will eliminate an organizational layer, reflecting Allergan's belief in a lean and efficient business model. Pyott previously served Allergan in the role of President from 1998 until 2006.

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ABB Concise Presents 2011 Practice Partnership Webinar Series, COPE Accreditation Pending

ABB Concise has announced the 2011 schedule of the free webinar series it cosponsors with Paragon Vision Sciences and Primary Eyecare Network (PEN), with pending COPE accreditation. The webinar series focuses on topics that support successful treatment options and outcomes with gas permeable lens fitting. Patrick Caroline, FAAO, of Pacific University, leads the webinars.

New in 2011, ABB Concise's practice management division, PEN, will be administering the webinars in order to provide the interested attendees the opportunity to receive CE credits. The February webinar has received COPE approval and the remaining classes have COPE accreditation pending. The webinars are free for all that are interested in attending. Those looking for the CE credits will need to pay a nominal fee of $35 and pass a 10-question online exam.

The webinars are scheduled monthly on Wednesdays at 6:00pm Pacific time (9:00pm Eastern). The next one on Corneal Topography and Contact Lenses is March 16. To find information on all of the webinars and register, visit www.primaryeye.net/education, send an email to education@primaryeye.net or call 800-444-9230.

New Vice President of Operations for Blanchard

Blanchard Contact Lens, Inc. announced the promotion of Robert Martin of the Manchester, New Hampshire lab, to Vice President of Operations.

Robert "Bob" Martin has 27 years of industry experience. His tenure with Blanchard began at its inception in 1986 and spans a total of 19 years in the roles of Director of Laboratory Affairs and Director of Operations. One of Bob's most recent achievements is as the designer of the company's Bi-Aspheric Multifocal GP lens, Reclaim HD.

AmeriSciences Launches OS2

AmeriSciences recently introduced Ocular Support Solution (OS 2) dietary supplement, their newest vision care formulation. OS2 was developed to incorporate the latest research on supplementation as it relates to AMD, Dry Eye Syndrome and Diabetic Retinopathy.

At the heart of AmeriSciences' OS2 are the carotenoids (lutein, zeaxanthin, and astaxanthin), Omega-3 fatty acids, alpha lipoic acid, Vitamin D, and zinc. According to the company, studies show that carotenoids are best absorbed when taken in combination with oil rather than water. Thus, utilizing a molecularly-distilled fish oil base as the carrier to disperse and deliver these beneficial antioxidants will prove a leap forward in delivery technology for ocular nutrition supplements.

The company offers a convenient Easy Ship home delivery program to help increase compliance. For more information on OS2, visit www.amerisciencesrx.com.

March Contact Lens Spectrum

Check out the cover story in this month's issue of Contact Lens Spectrum, Managing Allergy in Contact Lens Wearers. Jeffrey C. Krohn, OD, FAAO and Alesha Jensen, OD discuss how a thorough evaluation, proper diagnosis, and timely treatment will help you bring relief to allergy sufferers.

Other feature articles include: Managing Corneal Dystrophies with Lenses by Long D. Tran, OD, FAAO; Case Closed: A Review of Contact Lens Case Care by Nicole Olboeter, BSc and Sibylle Scholtz, PhD; and Improving the Quality of Our Patients' Vision: Aspheric Lens Designs by Kathryn Richdale, OD, MS, FAAO.

Look for your issue in the mail to read these and other informative articles or review issue on line at: www.clspectrum.com/thismonth.aspx.
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TearScience Appoints O'Hara as Vice President of Sales

TearScience, Inc. announced the appointment of Jeff O'Hara as Vice President of Sales for North America. In this role, O'Hara will direct the company's U.S. and Canadian sales and customer service organizations.

O'Hara has more than 20 years of experience in the medical device industry. Prior to joining TearScience, O'Hara was the Vice President of sales for Lumenis and Managing Director of U.S. sales for Solta Medical. O'Hara earned a master's degree in business administration from James Madison University.

The company's LipiFlow treatment device is designed for use by eye care professionals to address a root cause of evaporative dry eye disease, meibomian gland dysfunction which results in a lipid deficiency of the eye's natural tear film. TearScience will begin commercializing its devices in Europe and Canada in 2011 and is currently seeking U.S. FDA clearance for its LipiFlow treatment device. For additional information, visit www.tearscience.com.

As I noted in my Editorial in the February issue of Contact Lens Spectrum, I've been hearing from practitioners about their observations of infiltrative keratitis in their contact lens wearing patients, in addition to their continued thoughts on corneal staining. Like corneal staining, infiltrative keratitis can present both symptomatically or asymptomatically, has been associated with a variety of contact lens wearing factors, and also occurs in non-lens wearers as well. Attempts have been made to quantify its rate of occurrence, although in my opinion, we need more data on this important outcome. Please take a moment to provide us your thoughts on your experience with the rate of infiltrative keratitis in the Quick Poll this week.

Survey of Contact Lens Prescribing to Infants, Children, and Teenagers

Researchers wanted to determine the types of contact lenses prescribed for infants (aged 0 to 5 years), children (6 to 12 years), and teenagers (13 to 17 years) around the world.

Up to 1,000 survey forms were sent to contact lens fitters in each of 38 countries between January and March every year for five consecutive years (2005 to 2009). Practitioners were asked to record data relating to the first 10 contact lens fits or refits performed after receiving the survey form.

Data were received relating to 105,734 fits [137 infants, 1,672 children, 12,117 teenagers, and 91,808 adults (age >/= 18 years)]. The proportion of minors (<18 year old) fitted varied considerably between nations, ranging from 25% in Iceland to 1% in China. Compared with other age groups, infants tend to be prescribed a higher proportion of rigid, soft toric, and extended wear lenses, predominantly as refits for full-time wear, and fewer daily disposable lenses. Children are fitted with the highest proportion of daily disposable lenses and have the highest rate of fits for part-time wear. Teenagers have a similar lens fitting profile to adults, with the main distinguishing characteristic being a higher proportion of new fits. Orthokeratology fits represented 28% of all contact lenses prescribed to minors.

The researchers concluded that patterns of contact lens prescribing to infants and children are distinctly different to those of teenagers and adults in a number of respects. Clinicians can use the data presented here to compare their own patterns of contact lens prescribing to minors.

Efron N, Morgan PB, Woods CA. Survey of Contact Lens Prescribing to Infants, Children, and Teenagers. Optom Vis Sci. 2011 Feb 17.