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January 1995

Tear Function IndexA New Measure of Dry Eye

Author Affiliations

From the Department of Ophthalmology, Tokyo Dental College, Chiba, Japan.

Arch Ophthalmol. 1995;113(1):84-88. doi:10.1001/archopht.1995.01100010086025

Objective:  To develop an efficient way to evaluate tear dynamics clinically.

Participants:  Three hundred fifty-two patients with dry eye, 64 of whom had Sjögren syndrome, and 55 normal subjects.

Design:  Because various forces that affect tear drainage are reflected in the values of the Schirmer test with anesthesia and the tear clearance rate, we introduced a new measure of tear dynamics, the tear function index, which is the value obtained from dividing the value of the Schirmer test with anesthesia by the tear clearance rate.

Results:  The tear function index was more specific (91.8%) and sensitive (78.9%) in diagnosing dry eye associated with Sjögren syndrome than was the Schirmer or tear clearance rate test alone. Tear function indexes below 96 were consistent with dry eye and those below 34 were seen primarily in patients with Sjögren syndrome.

Conclusions:  The tear function index offers a new method to evaluate tear production with the Schirmer test, introduces an extended way to measure tear flow combining with tear drainage, and gives a practical measure to diagnose dry eye.

Woldoff HS, Haddad HM.  Rose bengal in keratoconjunctivitis sicca . Ann Ophthalmol . 1973;5:859-861.
Mengher LS, Pandher KS, Bron AJ.  Non-invasive tear film break-up time: sensitivity and specificity . Acta Ophthalmol . 1986;64:441-444.Article
van Bijsterveld OP.  Diagnostic tests in sicca syndrome . Arch Ophthalmol . 1969;82:10-14.Article
Goren MB, Goren SB.  Diagnostic tests in patients with symptoms of keratoconjunctivitis sicca . Am J Ophthalmol . 1988;106:570-574.Article
Farris RL, Gilbard JP, Stuchell RN, Mandel ID.  Diagnostic tests in keratoconjunctivitis sicca . Contact Lenses . 1983;9:23-28.
Mishima S, Kubota Z, Farris RL.  The tear flow dynamics in normal and in keratoconjunctivitis sicca cases . In: Sloanes MP, ed. Proceedings of the 21st International Congress, Excerpta Medica International Series No. 222 . Princeton, NJ: Excerpta Medica; 1970:1801-1805.
Clinch TE, Benedetto DA, Felberg NT, Laibson PR.  Schirmer's test: a closer look . Arch Ophthalmol . 1983;101:1383-1386.Article
Hamano H, Hori M, Hamano T, et al.  A new method for measuring tears . CLAO J . 1983;9:281-289.
Tsubota K.  The importance of the Schirmer test with nasal stimulation . Am J Ophthalmol . 1991;111:106-108.
Lemp MA, Weiler HH.  How do tears exit? Invest Ophthalmol Vis Sci . 1983;24:619-622.
Zappia RJ, Milder B.  Lacrimal drainage function, I: the Jones fluorescein test . Am J Ophthalmol . 1972;74:154-159.
Zappia RJ, Milder B.  Lacrimal drainage function, II: the fluorescein dye disappearance test . Am J Ophthalmol . 1972;74:160-162.
Toda I, Fujishima H, Tsubota K.  Ocular fatigue is the major symptom of dry eye . Acta Ophthalmol . 1993;71:347-352.Article
Fox RI, Robinson CA, Curd JG, Kozin F, Howell FV.  Sjögren's syndrome: proposed criteria for classification . Arthritis Rheum . 1986;29:577-585.Article
Tsubota K, Toda I, Yagi Y, et al.  Three different types of dry eye syndrome . Cornea . 1994;13:202-209.Article
Ono M, Yoshino K, Ogawa Y, Tsubota K.  Tear clearance rate in normal and dry eye patients . Invest Ophthalmol Vis Sci (Suppl) . 1991;32:1113. Abstract.
Toda I, Tsubota K.  Practical double vital staining for ocular surface evaluation . Cornea . 1993;12:366-368.Article
Tsubota K, Yamada M.  Tear evaporation from the ocular surface . Invest Ophthalmol Vis Sci . 1992;33:2942-2950.
Duke-Elder S.  The conduction of tears . In: Duke-Elder, ed. System of Ophthalmology . London, England: Henry Kimpton; 1968;4:chap 8.