OSA-Vet is an instrument available to veterinary ophthalmologists to evaluate the composition and stability of the Precorneal Tear Film (PTF). It allows to better evaluate PTF qualitative deficiencies and make an accurate diagnosis of evaporative Dry Eye Disease (DED) due to imbalance of the three main PTF components:
The scattered light emitted by the OSA-Vet system allows to evaluate the interference patterns coming from the Lipid Layer (LL) of the tear film.
The different patterns can be classified according to LL thickness and quality.
The white LED allows to show the phenomenon of interference fringes, that depends on the different thicknesses of the lipid layer of the tear film.
By using a dedicated lipid layer grading scale, each interference pattern may be examined in a simple and straightforward way.
The system is provided with a kit of useful grids to perform various screenings. All filters are already present in the OSA-Vet package.
- A thick grid to observe the quality of the tear film
- A fine grid to evaluate the quality and the structure of tear film and measure the N.I.B.U.T.
- A Placido disc to highlight possible distortions or corneal and tear film irregularities.
The thickness of the tear meniscus that is observed on the eyelid margins provides useful information on the tear volume. The tear meniscus can be examined considering its height, regularity and shape.
In dogs and cats, the Pre-corneal Tear Film (PTF) is about 8 µm thick on the central cornea, but it is much thicker at the meniscus.
By examining the meniscus, it is possible to evaluate the lacrimal glands aqueous production.
The OSA-VET allows to study the tear film Non Invasive Break Up Time (N.I.B.U.T.).
The Break Up Time (B.U.T.) test studies the tear film break up time with the use of fluorescein dye on the cornea. This test can cause reflex tearing and change tear film properties.
On the contrary, the N.I.B.U.T. test is carried out without the use of fluorescein and is harmless and well tolerated in animals
To evaluate corneal topography and tear film defects by the projection of Placido rings on ocular surface.
Meibography allows to evaluate the morphology and drop out of the meibomian glands and to make the diagnosis of Meibomian Gland Dysfunction (MGD).
The software allows to analyze the functional and non functional areas, and to evaluate the extension of the affected area.
A convenient hand held device with two infrared filters and a built in camera. The OSA-Vet system captures and displays images of the meibomian glands straight on your computer.
- Seamless and wireless capturing of images for added convenience
- Image capture button freezes live images which are instantly displayed on the computer
- Captured image enhancement tools: contrast, brightness and hue
- settings to improve and highlight captured images
- Define area for analysis and visible area of glands. Calculations of gland loss is then displayed graphically
- Progression analysis provides a split screen for side by side image comparisons over time.
Our device easily and efficiently integrates complex examinations such as meibography and tear film interferometry screening. The I.C.P. allows to:
- Calculate the percentage of functional glands in a selected area
- Point out through a change of colour the areas with and without glands
- Classify in 4 different degrees the loss of meibomian glands
A. Loss between 0 and 25 %: green
B. Loss between 25 and 50%: yellow
C. Loss between 50 and 75 %: orange
D. Loss between 75 and 100%: red
- Change the brightness of the images for a better evaluation.
The I.C.P. (Integrated Clinical Platform) allows to record good quality images and to study the length and width of meibomian glands.
The images are automatically classified.
The position of the meibomiam glands in the eyelids is automatically detected.
Evaluation of corneal diameter from limbus to limbus (white-to-white distance, WTW).
OSA VET Brochure (English)
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