Abstract
Purpose: :
To discuss the utilization of the fourth generation Fourier domain anterior segment OCT in the imaging and measurement of tear meniscus and evaluate its effect on diagnosis of dry eye.
Methods: :
We enrolled 120 cases (120 eyes) and 103 controls (103 eyes) in this study. The tear meniscus height (TMH), tear meniscus depth (TMD) and tear meniscus area (TMA) of each participant were measured by Fourier domain OCT RTVue-100. We also performed BUT, fluorescein staining and Schirmer test, and recorded score of the dry eye questionnaire. The relativity of clinical examinations was tested, the tear meniscus of the two groups were measured and ROC curves were drawn.
Results: :
The Spearman correlation analysis showed the TMH, TMD and TMA were parallel with the severity of patients’ signs and symptoms. The average values of TMH, THD and TMA in the patient group were 232.319 ± 17.549 µm, 151.494 ± 12.811 µm, 0.024428 ± 0.003712 mm2, comparing with 328.113 ± 19.036 µm, 220.906 ± 12.935 µm, 0.045618 ± 0.005623 mm2 in the control group, the difference of which reached significant (P=0.0000). Age was negatively correlated with the tear meniscus (TMH r=-0.0649, TMD r=-0.0299, TMA r=-0.0320). The individual variability of the TMH, TMD and TMA in the patient group was less than the control group. The repeatability analysis showed a small variation in measurement. The specificities in diagnosis of dry eye by different OCT values were TMH 72.20%, TMD 71.75%, TMA 73.09%. The area under the ROC curve was 0.7740 (TMH), 0.7841 (TMD) and 0.7855 (TMA). The cut-off point of diagnosis was 263.6667 µm (TMH), 165.6667 µm (TMD) and 0.0286667 mm2 (TMA). The OCT images of the bound and cross section area of the tear meniscus and the clarity of the tear fluid in the patient group were obviously different from those in the control group.
Conclusions: :
The Fourier domain anterior segment OCT can clearly image and measure the cross section of tear meniscus, the result of which showed a good coherence with the traditional diagnostic test (BUT, Schirmer test) and directly reflect features of the tear meniscus. As a non-traumatic and non-contact technique, the Fourier domain anterior segment OCT has a favorable prospect in the diagnosis of dry eye.
Keywords: cornea: tears/tear film/dry eye • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical