Skip Navigation LinksHome > December 2006 - Volume 25 - Issue 10 > Tear Film Normalization Test: A New Diagnostic Test for Dry...
doi: 10.1097/01.ico.0000240085.21105.51
Clinical Science

Tear Film Normalization Test: A New Diagnostic Test for Dry Eyes

Latkany, Robert MD; Lock, Barbara G MD; MD, Mark Speaker PhD

Collapse Box


Purpose: To evaluate the normalization of the tear film (tear film normalization test [TNT]) as a diagnostic test for dry eye syndrome.

Methods: The uncorrected distance vision of 20 patients with dry eyes (40 eyes) and 20 normals (40 eyes) before and after instillation of carboxymethyl cellulose 0.5% (CMC; Refresh Plus; Allergan, Irvine, CA) was recorded. We used study early treatment diabetic retinopathy (ETDRS) vision charts to test vision in each eye. Tear film breakup time (TBUT), presence or absence of superficial punctate erosions (SPE), tear film meniscus height, meibomian gland function, and ocular surface disease index (OSDI) questionnaire scores were evaluated.

Results: CMC improved visual acuity in the dry eye group (P < 0.0001). Response operator's curve (ROC) analysis showed that vision improvement of 2 lines or more after tear normalization was associated with an 82.5% (95% CI: 66.6%-92.1%) sensitivity and 100% (95% CI: 89.1%-100%) specificity for dry eye. There was a significant correlation between vision improvement and OSDI score in the dry eye group (P = 0.003).

Conclusion: The TNT is a highly sensitive and specific test for dry eyes and is available in every eye care professional's office. The more symptomatic the dry eye, the greater the improvement.

© 2006 Lippincott Williams & Wilkins, Inc.


Article Tools


Article Level Metrics

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.