Touch Tear MicroAssays

Interpretation and Application of Results

Lactoferrin Data
(mean values from clinical studies)

Normal 1.4 mg/ml
Low <0.9 mg/ml

IgE Data
(mean values from clinical studies)

Vernal conjunctivitis 341 ng/ml
Allergic conjunctivitis 204 ng/ml
Bact/Viral conjunctivitis 57 ng/ml
Normal 39 ng/ml

Tear Clearance Rate
(Research Use Only)

Normal >10% per minute
Low <10% per minute

Applications

Note: Before elective procedures such as new fit for Contact Lenses or LASIK, the doctor may desire to profile the patient's tear chemistry. This may be important since certain procedures or medications can induce dry eye or cause the patient to fail to comply with protocols (e.g. non-cleaning of lenses) that may lead to inflammation. Under this circumstance, each patient can serve as their own control (to establish the existing baseline). Later testing will reveal changes in the patient's response to the procedure.

Contact lens applications:

Tear Chemistry Indication Possible Risk for CL Wear
Normal Lactoferrin Normal lacrimal function Good CL candidate
Low Lactoferrin 1. Suppressed lacrimal function
2. CL desensitization		 a. Hypoxia
b. Bacterial conjunctivitis
c. CL dehydration
High Lactoferrin Elevated tear proteins Excess CL deposits
Elevated IgE Sub-acute allergic response GPC
High IgE Acute allergic response Inflammation

 

LASIK or PRK applications:

Tear Chemistry Indication Possible Risk for LASIK
Normal Lactoferrin Normal lacrimal function Good LASIK candidate
Low Lactoferrin Suppressed lacrimal function Myopic outcome
High Lactoferrin Elevated tear proteins Hyperopic outcome
High IgE Allergic response Regression, PRK haze

 

Dry Eye applications
(with patients complaining of dry eye)

Tear Chemistry Indication Possible cause for dry eye symptoms
Normal Lactoferrin Normal lacrimal function Evaporative dry eye
Low Lactoferrin Suppressed lacrimal function Aqueous deficient tear film
(good candidate for punctal occlusion)
High Lactoferrin Elevated tear proteins Evaporative dry eye
Normal IgE No allergic involvement Non-allergic etiologies
High IgE Allergic response a. Allergic involvement
b. Secondary evaporative dry eye
Normal TCR Normal tear turnover Non-aqueous etiologies
Low TCR Dysfunctional lacrimal gland Diminished tear turnover

 

Ocular inflammation (Red Eye) applications:

Tear Chemistry Indication Possible cause of inflammation
Normal Lactoferrin Normal lacrimal function Chronic etiology
Low Lactoferrin Suppressed lacrimal function Acute etiology
Low IgE No allergic involvement Non-allergic etiology
Elevated IgE Allergic involvement a. Sub-acute response to bacterial exotoxin
b. Sub-acute response to viral antigens
High IgE Allergic response Allergic involvement