Original ResearchExamination of Gland Dropout Detected on Infrared Meibography by Using Optical Coherence Tomography Meibography
Introduction
Meibomian glands are a type of sebaceous glands located in the eyelids and consist of excretory acini connected with long central ducts via short ductules.1, 2 Each acinus is composed of several meibocytes whose contents (meibum) are secreted in a holocrine manner.1, 3 These excretions play a vital role in forming the lipid component of tear films, and are essential for ensuring stability and maintenance of the ocular surface.4
Meibomian gland dysfunction (MGD) is caused by the hyperkeratinization of the excretory duct and orifice, or by degenerative atrophic processes as a result of aging, contact lens use, or inflammatory events.1, 4, 5, 6, 7 MGD is considered as one of the main causes of dry eye. MGD-related dry eye leads to the disturbance of tear film composition, wherein the change in the lipid phase of the tear film is greater than that in the aqueous phase.8
This condition can be diagnosed via indirect methods, such as tear osmolarity, tear break-up time (TBUT), and lipid layer thickness (LLT),9 or via direct methods such as meibography, which yields images of the meibomian glands using transillumination or infra-red (IR) light.10, 11, 12 Although indirect methods are objective in nature, they may be associated with a certain degree of interobserver or intraobserver error. In contrast, the direct method enables the observation of the detailed anatomic structure of the meibomian glands.
IR meibography is commonly used in the clinical setting as a direct method for diagnosis, and enables the two-dimensional imaging of the meibomian glands.4 Using this technique, the abnormal structure of the meibomian glands, such as in cases of gland dropout, can be confirmed; however, the detailed anatomic structure of the acini or ducts in the meibomian glands cannot be clearly elucidated. Furthermore, two-dimensional IR imaging does not yield depth information, and the results may vary depending on the amount of light from the external source. Ngo et al.13 reported that dropout scores based on the IR images for meibomian glands did not correlate with clinical signs, and suggested the need for an another method to evaluate the structural changes, including dropout.
Three-dimensional meibography imaging via swept-source/Fourier-domain optical coherence tomography (OCT) was developed to resolve the problems associated with two-dimensional images from IR meibography.14 The OCT system uses a long coherence swept laser source with a wavelength (1300 nm) close to that of IR light to enhance the OCT imaging depth range.
To our knowledge, no study has clarified the detection of dropout of the meibomian glands on IR imaging by using OCT images. In the present study, we aimed to elucidate the anatomic details of gland dropout on IR images based on the data obtained via OCT imaging.
Section snippets
Methods
Subjects: In this cross-sectional study, we examined cases of meibomian gland dropout, as observed on IR meibography, among patients who visited Seoul Saint Mary's Hospital with symptoms of dry eye between November 2014 and July 2015. The gland dropout on IR meibography in the lower eyelids was excluded because OCT meibography did not yield sufficient data to elucidate the anatomic details of this region. Moreover, the other exclusion criteria were as follows: history of any ocular surgery
Results
Based on IR meibography findings, a total of 275 cases of meibomian gland dropout were enrolled in this study. 115 eyes of 64 subjects with gland dropout exhibited the evaporated type of dry eye associated with meibomian gland dysfunction. Moreover, the Schirmer test result (8.74 ± 6.76 s), TBUT (4.34 ± 2.54 s), and corneal staining score indicated the state of instability of the tear film, whereas the lid margin abnormality score showed a condition similar to that noted in cases of MGD (Table 1
Discussion
In the present study, we aimed to elucidate the anatomic details of gland dropout by using OCT meibography in cases with a loss of meibomian glands on IR imaging. Cases with gland dropout, detected via IR imaging, were classified into 3 groups based on the detailed information of the acini or ducts of the meibomian glands obtained on OCT imaging.
The determination of the changes in the acini in the meibomian glands is important for the diagnosis and management of MGD in the clinical setting.
Conclusion
OCT images yield detailed information regarding the acini and ducts in cases with dropout of the meibomian glands, which cannot be obtained via IR imaging. The loss of the meibomian glands on IR imaging should be carefully interpreted, and OCT imaging can be considered to determine the actual loss or changes in the meibomian glands. The correlation between the structural changes in the meibomian glands and clinical parameters of the tear film, as well as the changes over time may represent a
Acknowledgments
We thank the individuals who carefully managed the data regarding dry eye examinations. The statistical analyses performed in this study were reviewed by the Department of Biostatics at The Catholic University of Korea.
References (41)
- et al.
Noncontact infrared meibography to document age-related changes of the meibomian glands in a normal population
Ophthalmology
(2008) - et al.
Contact lens wear is associated with decrease of meibomian glands
Ophthalmology
(2009) - et al.
Meibomian gland function and giant papillary conjunctivitis
Am J Ophthalmol
(1992) - et al.
Age-related changes in the meibomian gland
Exp Eye Res
(2009) - et al.
Comparison of subjective grading and objective assessment in meibography
Cont Lens Anterior Eye
(2013) - et al.
Increased tear fluid production as a compensatory response to meibomian gland loss: A multicenter cross-sectional study
Ophthalmology
(2015) - et al.
Low-concentration homogenized castor oil eye drops for noninflamed obstructive meibomian gland dysfunction
Ophthalmology
(2002) - et al.
Effects of eyelid warming devices on tear film parameters in normal subjects and patients with meibomian gland dysfunction
Ocul Surf
(2015) - et al.
The international workshop on meibomian gland dysfunction: report of the subcommittee on anatomy, physiology, and pathophysiology of the meibomian gland
Invest Ophthalmol Vis Sci
(2011) - et al.
Wolff's Anatomy of the Eye and Orbit
(1997)
Meibomian gland studies: comparison of steer and human lipids
Invest Ophthalmol Vis Sci
Anatomy and histopathology of human meibomian gland
Cornea
The international workshop on meibomian gland dysfunction: executive summary
Invest Ophthalmol Vis Sci
Evaluation of lipid layer thickness measurement of the tear film as a diagnostic tool for Meibomian gland dysfunction
Cornea
Objective image analysis of the meibomian gland area
Br J Ophthalmol
Validity of noninvasive meibography systems: noncontact meibography equipped with a slit-lamp and a mobile pen-shaped meibograph
Cornea
A review of meibography
Optom Vis Sci
Repeatability of grading meibomian gland dropout using two infrared systems
Optom Vis Sci
In vivo 3D meibography of the human eyelid using real time imaging fourier-domain OCT
PLoS One
Grading of corneal and conjunctival staining in the context of other dry eye tests
Cornea
Cited by (30)
Latest developments in meibography: A review
2022, Ocular SurfaceCLEAR - Contact lens complications
2021, Contact Lens and Anterior EyeCitation Excerpt :Imaging using OCT allows three-dimensional evaluation of the meibomian glands compared with two-dimensional evaluation using meibography or IVCM. One study found a 50% discrepancy in the assessment of meibomian gland dropout with infrared meibography compared with a images acquired using a customised OCT [366]. However, to date, no peer reviewed publications have evaluted meibomian gland characteristics amongst contact lens wearers using OCT.
The role of meibography in ocular surface diagnostics: A review
2021, Ocular SurfaceLatest evidences on meibomian gland dysfunction diagnosis and management
2020, Ocular SurfaceCitation Excerpt :They also found a higher percentage of disagreement in the middle portion of the upper eyelid, probably because of the more uniform palpebral thickness in the middle area compared to the nasal or lateral ones. With OCT imaging Yoo et al. [30] obtained more detailed information about the anatomical structure of meibomian glands previously evaluated solely with meibography whose results have to be carefully interpreted. It was also stated that in the future a more appropriate treatment may be adopted based on OCT anatomic features like the status of the acini: their absence would require lipid-containing eye drops or ointment, while their progressive loss on obstructive MGD would require meibum secretion improving therapies.
In vivo Meibomian gland imaging techniques: A review of the literature (French translation of the article)
2020, Journal Francais d'OphtalmologieIn vivo Meibomian gland imaging techniques: A review of the literature
2020, Journal Francais d'OphtalmologieCitation Excerpt :This change in MG volume might correspond to atrophic degeneration of the acinar tissue of the MG's described in ex vivo histologic studies or a MG loss observable on meibography. A satisfactory correlation has been shown between MG evaluation based on infrared-coupled OCT and contact meibography with lid transillumination [51,52]. The analytic performance of meibography compared to OCT with three-dimensional reconstruction has been evaluated in a population of dry eye patients.
The authors have no commercial or proprietary interest in any concept or product described in this article.
Single-copy reprint requests to Choun-Ki Joo, MD, PhD (address below).
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
This article contains additional online-only material. The following should appear online-only: Supplemental Table, Video 1, and Video 2.
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Choun-Ki Joo and Tae Joong Eom contributed equally to this work.