Tear meniscus measurement by spectral optical coherence tomography.

PURPOSE: To evaluate the use of lower tear meniscus measurements obtained with anterior segment Spectral Optical Coherence Tomography (OCT) in quantitative tear evaluation and diagnosis of dry eye syndrome. To verify sensitivity and specificity of different tear meniscus parameters in diagnosis of dry eye syndrome.

METHODS: A total of 111 eyes in consecutive patients, mean age 34.35 years (SD, 11.17), were enrolled. Each patient completed a standard Ocular Surface Disease Index questionnaire and general ophthalmic examination. Lower tear meniscus was evaluated using Spectral OCT (RTVue, Optovue) with cornea-anterior segment lens short. Three parameters were measured: tear meniscus cross-section area (TMA, mm), tear meniscus height (TMH, mm), and tear meniscus depth (TMD, mm). Break-up time and Schirmer tests after instillation of topical anesthetic drops were also evaluated.

RESULTS: The highest correlation with Schirmer test results was found with TMA, followed by TMH and TMD. Respective Spearman correlation coefficient values were 0.54, 0.52, and 0.3, respectively. TMA, TMH, and TMD measurements were significantly lower in dry eyes than in controls. Sensitivity and specificity for dry eye diagnosis were 80.56% and 89.33% for TMH, 86.11% and 85.33% for TMA, and 77.78% and 52.7% for TMD, respectively. There was a significant negative correlation between both TMA and TMH and Ocular Surface Disease Index questionnaire scores.

CONCLUSIONS: Lower tear meniscus parameters measured with Spectral OCT correlate well with the Schirmer test, break-up time, and subjective symptoms. TMA and TMH measurements have high sensitivity and specificity for the diagnosis of dry eye syndrome.