i-Onion™ is an instrument that stimulates safely maximal tear secretion in an easy, brief and reliable manner.
How does i-Onion™ do that?
Basal tear flow is measured with a Schirmer test strip (ST) placed on the lower lid (3 min.) on the eye.
The i-Onion™ instrument is applied on the socket of the contralateral eye, immediately after a ST strip is in place. A CO2 gas puff is directed onto the eye.
A CO2 gas puff is directed onto the eye surface for 4 seconds.
The i-Onion™ is removed.
The ST strip is removed 3 min. later.
The numerical value obtained shows the maximal lacrimal secretion capacity.
Scientific Principles and foundations
Disorders leading to reduced eye surface wetness affects 10-20% of the
world population. However, the traditional procedures hitherto used for a
rapid and simple assessment of the lacrimal production in normal or
pathological conditions are rough and limited in the daily clinical practice
to the measurement of basal tear secretion by the lacrimal gland at rest
using the Schirmer test. This approach does not provide any clue on how
far the measured basal tear flow value is from the maximal secretory
capacity of the lacrimal glands, neither detects whether the gland still
possesses a tearing reserve volume large enough to supply the tear flow
required. This is critical information to decide the use drugs
(secretagogues) that activate lacrimal gland’s secretion.
The i-Onion™ instrument is a brand-new ophthalmological device
conceived and de built up by Tearful SL, that allows to obtain a
quantitative evaluation of the maximal tear secretion capacity of the
lacrimal glands in human and other mammal’s eyes in healthy or
pathological conditions. To obtain this result, the i-Onion™ instrument
releases a 3-second, 200ml/min, 99.9% medical grade CO2 gas jet onto
the surface of the explored eye, producing a total excitation of the
corneo-scleral nerve terminals mediating reflex secretion, thereby
causing a controlled, transient maximal reflex production of tears by the
lacrimal glands. The volume of tears produced by the stimulus impinging
on the cornea of the explored subject, can be measured by qualified
health personnel, using Schirmer test strips or any other ophthalmic
technique used for tear flow measurement.
USE CASES
Dry Eye Disease (DED) prevention
Assessment of lacrimal gland reserve values with the i-Onion™ procedure can support prediction in advance of several pathologies such as: DED/Sjögren & Video Display Terminal (VDT)- associated DED patients.
Predict patient’s tolerance to contact lens
Exploration with i-Onion™ stimulation prior to contact lens fitting, provides quantitative information about the magnitude of the functional tearing capacity of the patient.
Systematic measurement of this parameter previously to lens use helps optometrists and ophthalmologists to predict patient’s tolerance to contact lens and define appropriate strategies to reduce the risk of complications derived of contact lens use.
Systematic measurement of this parameter previously to lens use helps optometrists and ophthalmologists to predict patient’s tolerance to contact lens and define appropriate strategies to reduce the risk of complications derived of contact lens use.
Pre-surgery information
Exploration with i-Onion™ of the maximal tear reserve provides useful pre-surgery information of the Photorefractive procedure, information about risks associated to nerve injury-induced decreased tear flow.
Evaluate animal’s lacrimal gland capacity to secrete tear
Use of i-Onion™ to objectively evaluate in pets the lacrimal gland capacity to secrete tear can be useful in veterinary medicine. Yearly health examination for DED in predisposed breeds of dogs has been recommended by specialists in veterinary ophthalmology.