TearLab OSMOLARITY, Инструкция по эксплуатации

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4 930088 Rev M
TEST CARDS ENGLISH
For professional in vitro diagnostic use. CLIA Complexity: Waived
CLIA CONSIDERATIONS
The TearLab® Osmolarity System is a CLIA-waived test system for human
tears. Each laboratory or testing site using the TearLab Osmolarity System
must have a CLIA Certificate of Waiver before starting testing. To obtain a
Certificate of Waiver, call your state department of health or TearLab
Customer Support at 1-858-455-6006 for an application (Form CMS-116).
TearLab can provide the phone number of your state department of
health and assist you in filling out the application. The TearLab Osmolarity
System is a waived test so long as it is used according to the instructions
in the Package Insert. Any modification by the laboratory to the test
system or the test system instructions will result in this test no longer
meeting the requirements for waived categorization. A modified test is
considered to be high complexity and is subject to all applicable CLIA
requirements.
INTENDED USE
The TearLab Osmolarity System is intended to measure the osmolarity of
human tears to aid in the diagnosis of Dry Eye Disease in patients
suspected of having Dry Eye Disease, in conjunction with other methods
of clinical evaluation.
SUMMARY AND EXPLANATION OF THE TEST
Tears fulfill an essential role in maintaining ocular surface integrity,
protecting against microbial challenge, and preserving visual acuity.
1
Hyperosmolarity has been described in the literature as a primary marker
of tear film integrity.
2
When either the quantity or the quality of secreted
tears is compromised, the total osmolarity of the tear film is increased due
to increased evaporation. As a result, basal tear equilibrium is shifted to a
saltier solution, which places stress on the corneal epithelia and
conjunctiva. The TearLab® Osmolarity Test Card, in conjunction with the
TearLab Osmolarity System, provides a quick and simple method for
determining tear osmolarity using nanoliter (nL) volumes of tear fluid
collected directly from the ocular surface.
PRINCIPLES OF THE PROCEDURE
The TearLab Osmolarity test utilizes a temperature-corrected impedance
measurement of tear fluid to provide an indirect assessment of
osmolarity.
3 A voltage is applied to the tear fluid, and the electrical
impedance of the dissolved tear fluid particles is monitored over time.
After application of a calibration curve to the steady-state electrical
impedance of the tear fluid, osmolarity is calculated and displayed as a
quantitative numerical value.
MATERIALS
TearLab Osmolarity Test Card: A single-use, individually packaged,
nonsterile, polycarbonate microchip containing (a) a microfluidic channel
to collect 50 nanoliters (nL) of tear fluid by passive capillary action, and (b)
gold electrodes embedded in the polycarbonate card to enable
measurement of the impedance of the tear fluid sample in the
microfluidic channel. Each Test Card is clinically hygienic and contains a
protective cover. Test Cards are designed to work in conjunction with the
TearLab Osmolarity System.
REAGENTS
Test Cards contain no reagents or chemicals.
Materials provided: Osmolarity Test Cards
Materials Not Provided: TearLab Osmolarity System, consisting of:
Reader, Pens, and Electronic Check Cards
Accessories: Normal and High Osmolarity Control Solutions
PRECAUTIONS
1. For in vitro diagnostic use only.
2. Leave the Test Card in its sealed pouch until just before use.
3. Do not remove the protective cover until the Test Card is attached onto
a Pen and immediately prior to tear collection.
4. Avoid touching the tip of the Test Card.
5. Do not use a Test Card past its expiration date.
6. Test Cards are single-use only.
7. Use only at ambient temperature of 15° - 30°C/59° - 86°F.
8. The American Academy of Ophthalmology (AAO) states that “human
tears are not considered to contain significant amounts of bloodborne
pathogens, and thus do not require OSHA’s [Occupational Safety and
Health Administration’s] bloodborne pathogens precautions; but
exposure to human tears does require good office hygiene practices
such as hand washing. However, contact with tears contaminated with
blood, such as in minor surgery, requires the use of bloodborne
pathogen precautions.”
9. TearLab is designed to collect samples of tear fluid from the eye, a
nonsterile environment. The AAO has issued guidance to minimize the
transmission of ocular surface infectious agents.
4 Prevention of
transmission of these pathogens requires good hygienic techniques,
such as hand washing and the cleanliness of instruments that would
contact the eye. TearLab Osmolarity Test Cards are single-use, are
clinically hygienic and contain a protective cover, and are individually
packaged. No cleaning is required.
Although the device is manufactured to a level of disinfection deemed
appropriate by the CDC (Division of Healthcare Quality Promotion;
“Disinfection and Sterilization of Patient-Care Equipment, 1985”; last
modified June 22, 2005), it is not sterile and there is a minimal risk of
infection, ocular abrasion, or vision loss, as there is with any foreign object
that is brought in contact with the eye. Appropriate hygiene and care
should be adhered to.
STORAGE AND STABILITY
Store Osmolarity Test Cards at controlled room temperature (20° -
25°C/68° - 77°F); excursions are permitted to (15° - 30°C/59° - 86°F).
IMPORTANT:
Test Cards not stored at room temperature should be at
ambient temperature before use. Cold Test Cards may require several
minutes to reach ambient temperature. Osmolarity Test Cards are stable
until the expiration date marked on the label.
CALIBRATION DATA
To determine clinical performance for tear film hyperosmolarity in the
diagnosis of Dry Eye Disease, a meta-analysis was performed on historical
published data for tear osmolarity in samples of Normal and Dry Eye
subjects.
5
An osmolarity referent 316 mOsms/L was found to yield
sensitivity of 69%, specificity of 92%, and an overall predictive accuracy of
82% for the diagnosis of Dry Eye Disease. Studies in the meta-analysis
used earlier osmolarity devices, not TearLab.
PERFORMANCE OF OSMOLARITY IN META-ANALYSIS
Normal Dry Eye Total
≤316 750 192 942 80% NPV
>316 65 429 494 87% PPV
Total 815 621 1,436
Specificity
92%
Sensitivity
69%
PERFORMANCE ON PATIENTS WITH OBJECTIVE SIGNS OF
DRY EYE
140 subjects were enrolled in a multicenter study (n = 45 Normal, n = 95
Dry Eye). To qualify as a Dry Eye patient, subjects were required to have a
positive score on the Ocular Surface Disease Index (OSDI) and 2 or more
positive indications of Tear Film Breakup Time (TBUT), Schirmer Test,
Corneal Staining, Conjunctival Staining, or Meibomian Gland Dysfunction.
Performance of the TearLab® Osmolarity System using these selection
criteria is shown in the table below.