Measurement of the Lower Lid Margin Thickness by Anterior Segment Optical Coherence Tomography

Abstract

Purpose: To verify the feasibility of using anterior segment optical coherence tomography (AS-OCT) to measure the lower lid margin thickness (LLMT) from posterior lash line to the mucocutaneous junction. Methods: This was a prospective, single-center, observational study. Fifty-six volunteers between 20 and 79 years old with normal healthy eyes were included in this study. Using AS-OCT to measure the LLMT at the middle position was separately performed by two operators under the same conditions. Results: The mean age of 56 subjects (24 males and 32 females) was 45.4 ± 15.7 years. The LLMT measured by AS-OCT between two operators was 0.86 ± 0.23 mm and 0.85 ± 0.22 mm, respectively. The reliability and repeatability between two operators were evaluated by intraclass correlation coefficient (ICC = 0.97). Based on one operator’s measurements, the LLMT was 0.70 ± 0.10 mm at ages 20–29, 0.68 ± 0.09 mm at ages 30–39, 0.94 ± 0.12 mm at ages 40–49, 0.93 ± 0.20 mm at ages 50–59, 1.03 ± 0.15 mm at ages 60–69, and 1.24 ± 0.19 mm at ages 70–79, which indicated a significant positive correlation with age (r_s = 0.74, p < 0.001). In addition, there was a significant difference in the LLMT between genders (0.94 ± 0.26 vs. 0.80 ± 0.19 mm, p = 0.03). Conclusions: A good agreement between two operators indicated that it seemed to be feasible to use AS-OCT to measure the LLMT. Additionally, we found that the LLMT appeared to be closely related to age and gender.

Measurement of the Lid Margin Thickness in Meibomian Gland Dysfunction with Vernier Micrometer

“…Previous studies [8,28] had shown that the lid margin thickened with age because of enlargement of the orbicularis and meibomian glands in the first 20 years of life, but the LMT in adults did not change with age. Contrary to the above conclusions, our present and previous studies [15,17] suggested that the LMT, especially the lower LMT, also seemed to be related to age. This further supported the literature reports on age-related changes in the lid margin anatomy [3,8,28] and the theory that the incidence of MGD increased with age [2][3][4][5][6][7].…”

“…Although the LMT is difficult to measure, people are still trying to measure it with several different methods [15][16][17][28][29][30]. Hykin et al [8] suggested that the lid margin width in normal adults including wet mucosa was approximately 2.5 mm.…”

“…This was a single-center, prospective, cross-sectional, observational study, which was an extension of our previous works [15][16][17]. In this study, 100 volunteers (40 males and 60 females) aged 20 to 79 years were recruited from the ophthalmic clinic of Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, including 56 participants with healthy eyes and 44 participants with MGD.…”

“…Study Exclusion Criteria [15][16][17]: irregular lid margin structures-cicatrices, dimpling or notching, serration; meibomian gland loss area [ 33% of the total area in each eyelid [4]; history of chalazion or hordeolum within the past 3 months; eyelid tattoos; ocular surface disease index (OSDI) score\12 points in MGD subjects; active ocular allergies; ocular infection/inflammation; entropion and trichiasis; eyelid tumor; no eyelashes or central eyelashes loss; conjunctivochalasis; nystagmus; paralytic strabismus; have worn contact lens within the past 3 months; had a history of intraocular surgery or ocular surgery; used isotretinoin (accutane) within the past 6 months; autoimmune disease requiring systemic treatment; was pregnant or lactating.…”

“…Through the previous studies [15][16][17], we found that the LMT from the posterior lash line to the mucocutaneous junction (MCJ) was a relatively constant feature of the lid margin in normal adults and could be quantitatively measured by anterior segment optical coherence tomography (AS-OCT), oculus keratograph and vernier micrometer (VM). However, we only reported the data of the lower LMT, not the data of the upper LMT.…”