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MAIN USE
Lipid layer examination
Through the device it is possible to do an interferometric analysis of the lipid layer in the tear film.
The tear film plane must be focused, while the image of the bright circle must remain blurred.
Depending on its thickness and regularity, the lipid layer may appear like any of the following: amorphous
structure, marble appearance, wavy appearance, yellow, brown, blue or reddish interference fringes.
Height of the inferior tear meniscus
Most tears are collected in the inferior and superior tear meniscus. The size of the tear meniscus formed on
the eyelid borders provides useful information on the volume of tears produced. The tear meniscus can be
examined considering its height, regularity and shape. Gradation is not accurate when there are reflected
tears. IDRA’s brightness is calibrated so as not to cause any glare in the patient examined; besides, the light
being cold it does not induce excessive reflected lachrymation.
IDRA allows you to highlight shape and height of the tear meniscus without using any staining, hence
without altering tear composition.
A standard tear meniscus is convex near the eyelid margin and concave at the center. The standard tear
meniscus, observed with IDRA, presents with a typical black line near the convex part of the meniscus
profile.
Tear film stability and regularity
IDRA allows to evaluate stability and regularity of the tear film, using non-invasive break up time
measurement (NIBUT). In fact, the appropriate cone can be inserted inside IDRA’s to project structured
images on the tear film surface. By examining the regularity of the image reflected by the tear film the tear
film NIBUT can be measured. The non-invasive break up time is the measurement, in seconds, of the time
between the last complete blinking and the appearance of the first discontinuity on the tear film. The device
can also be used to observe the pre-rupture phase indicating tear film thinning time.
For accurate measurement, the patient must be properly instructed. During the exam, the patient must look
in front of him/her and is encouraged to slightly blink. Then ask to the patient to keep his/her eyes open,
without blinking for as long as possible. The seconds between the last full blinking and the first rupture of
the image reflected on the tear film are counted with a chronometer.
Meibography
Through IDRA you can evaluate the Meibomian Glands thanks to infrared image analysis. It allows you to
evaluate the quantity of glands overall palpebral area.
Once evaluated the exam, the software will give you the 3D shape of glands to understand in which areas
there is a loss.
