The New Face of Dry Eye Management
These new devices can help you in your efforts to diagnose and treat dry eye.
Tara Rosenzweig, contributing editor
Dry eye affects an estimated 5% to 30% of those age 50 and older, says the 2007 report from the International Dry Eye Workshop published in The Ocular Surface. Fortunately, this population has not been neglected, as new technologies allow for enhanced detection and treatment of dry eye disease. An introduction to new devices, such as those included in this article, can help you, the optometrist, manage dry eye patients.
(Editor's note: As product specifications, FDA status, coding and reimbursement issues and prices change through time, we recommend you contact device manufacturers for updated information and specific product requests.)
TearLab Osmolarity System
■ The TearLab Osmolarity System (TearLab Corporation) measures osmolarity, or the amount of salt in tears. The system employs a “test card” to collect tear fluid from the eyelid margin. The System's Reader then calculates the tear osmolarity and displays it on an LCD display.
“Now we have a clinically applicable test that is easy and quick to perform and also is quite patient friendly,” says Barry Eiden, O.D., president and medical director of North Suburban Vision Consultants in Deerfield, Ill.
In a study of 300 patients, TearLab identified 88% of normal subjects, 75% of subjects who had mild-or-moderate dry eye disease and 95% of subjects who had severe dry eye disease using a diagnostic cutoff of 308mOsms/L.1 In addition, a study presented at ARVO 2010 revealed the TearLab device outperformed corneal staining and Schirmer's testing in correctly identifying patients who had mild-to-moderate dry eye.2
• Dimensions: TearLab Osmolarity System Reader: 10.25” (L) x 6” (W) x 5” (H).
• Cost: $9,500 to purchase or $308 per month to lease for 36 months. Both options include 80 free test cards, which are normally $10-$15 per card (depending on the number purchased).
• FDA Status: FDA clearance granted in 2009. (CLIA) Waiver categorization by the FDA in January 2012.
• Info: www.tearlab.com
■ TearScience's LipiFlow Thermal Pulsation System treats meibomian gland dysfunction (MGD) by unblocking eyelid glands through a combination of localized heat and intermittent pressure.
“LipiFlow has allowed us to provide eye care for a patient population that unfortunately typically gets ignored or brushed off.” says Ritesh Patel, O.D., with the Herzig Eye Institute in Toronto, CAN.
(See “Instrument Focus” on page 70 for further discussion on this device.)
■ The Oculus Keratograph (Oculus Optikgeräte GmbH) assesses tear film both qualitatively and quantitatively using non-invasive scanning software. The device has a tear film scan module that provides an objective assessment of tear break-up time, placido ring-based corneal topography, and it can also assess tear meniscus height.
“Changes in the projected placido rings (distortions of the margins of rings) give an indication of the break-up time of the tear film at any location on the tear film over the cornea,” says Sruthi Srinivasan, Ph.D., B.S. Optom, research assistant professor at the University of Waterloo School of Optometry in Ontario, Can.
The measurement of tear meniscus height “helps to determine the tear film quantity (amount of tears at the lower tear meniscus),” Dr. Srinivasan says. In addition, the Keratograph can capture images of the meibomian glands (MG) within both the upper and lower lids, she says.
“Devices such as this could also be used to monitor the status of the MG in patients with MGD and non-MGD.”
• Dimensions: Approximately 16.5” H x 6.5” D x 10” W; 5 lbs.
• Cost: About $13,000
• FDA status: Class 1 product, 501k not required
• Info: www.oculususa.com
RPS InflammaDry Detector
■ The InflammaDry Detector (Rapid Pathogen Screening [RPS]), detects elevated levels of matrix metalloproteinase-9 (MMP-9) in tear fluid. A 2009 study of 46 patients newly diagnosed with dysfunctional tear syndrome (DTS) and 18 control subjects showed that tear MMP-9 activity was significantly higher in the patients diagnosed with DTS. The study authors concluded that MMP-9 appears as a “potentially useful biomarker for diagnosing, classifying, and monitoring DTS.”3
To use the system, a small applicator (sample holder) is briefly touched to the conjunctiva. The sample holder then snaps into a test cassette, and results are obtained in 10 minutes.
“This test will give us insights into the complexity of the tear film and allow us to better understand the presence or absence of inflammatory markers, which will likely guide our treatment algorithms,” says Mile Brujic, O.D., of Premier Vision Group in Bowling Green, Ohio.
The test is similar to the company's Adeno Detector “only it is measuring the level of MMP-9 as opposed to [a] viral antigen,” says Dr. Brujic. He adds the test is low-cost, disposable and doesn't require any significant investment in special equipment.
“The results of the InflammaDry will now have the ability to help guide our treatment of patients' signs and symptoms of dry eye,” Dr. Brujic says.
• Dimensions: The applicator and testing cassette are each several inches long.
• Cost: About $13 (projected)
• FDA Status: Under FDA review (available in Europe and Canada)
• Info: www.rpsdetectors.com
■ Though not a dry eye device, the Opt-Align (Stereo Optical) identifies eye misalignment, which may be misdiagnosed as dry eye. Paul Karpecki, O.D., of Koffler Vision Group in Lexington, Ky., says both conditions share symptoms, including aching or pain in the eye, dryness (often described as grittiness), redness, burning and tearing, visual fatigue with near work and pulling on eyes with near work.
An Illinois College of Optometry study published in 2009 showed that eye misalignment can present as dry eye symptoms, most commonly burning and grittiness.4 According to Jeffrey Krall, O.D., one of the study's coauthors, convergence disparities can be subtle and still cause substantial eye strain that results in dry eye-like symptoms.5
Opt-Align works by utilizing several different tests: distance proprioceptive disparity, near proprioceptive disparity and vertical imbalance.
• Dimensions: 15” H x 15” D x 14.75” W; 18 lbs.
• Cost: $12,500
• FDA Status: FDA registered
• Info: www.opt-align.com. OM
References to this article are available upon request.
|Ms. Rosenzweig is a freelance writer and a former editor with Eyecare Business, a sister publication of OM. She lives in the Philadelphia area. To comment on this article, e-mail optometric firstname.lastname@example.org.|