The Meibomian Gland Composite Score (MGCS): A Novel Grading System Integrating Existing Scales for Meibomian Gland Dysfunction

Abstract

Purpose

To introduce and evaluate the clinical performance of the Meibomian Gland Composite Score (MGCS), a novel, standardized, video- and pictorial-based grading system designed to provide a linear, gland-specific assessment of meibomian gland dysfunction (MGD) severity.

Methods

The MGCS evaluates meibum quality on a 0 to 4 scale based on texture and expressibility across the central 8 upper eyelid glands (score 0–32) and central 5 lower eyelid glands (score 0–20). To evaluate clinical performance, two independent providers performed a retrospective chart review of 53 patients (mean age 60.9 ± 16.4 years; 75.5% female). Receiver operating characteristic (ROC) curves were generated using tear breakup time (TBUT ≤5 seconds) as the reference standard for evaporative dry eye disease (DED) to determine optimal diagnostic cut points.

Results

The MGCS demonstrated strong diagnostic accuracy for evaporative DED, with area under the curve (AUC) values of 0.9539 (right upper eyelid), 0.9182 (right lower eyelid), 0.9105 (left upper eyelid), and 0.7779 (left lower eyelid). An MGCS score ≥10 for an individual eyelid provided optimal diagnostic balance (sensitivity up to 93.75%, specificity up to 85.71%) for identifying abnormal gland function.

Conclusion

The MGCS offers a standardized and continuous scale for assessing MGD severity. By incorporating detailed meibum texture descriptions supported by standardized pictorial and video references, the scale facilitates precise disease tracking and robust statistical analysis in both clinical practice and research settings.

Plain Language Summary

Why was the study done?

Evaporative dry eye disease is a common condition that occurs when oil glands in the eyelids, known as meibomian glands, fail to produce healthy oil. This oil forms a protective layer on the eye’s surface, preventing tears from evaporating too quickly. When these glands become obstructed or inflamed, patients may experience chronic discomfort, redness, and visual disturbance. While several evaluation methods exist, eye care providers lack a universal, standardized scoring system to measure gland health, making it difficult to monitor disease progression or evaluate therapy effectiveness across different practices.

What did the researchers do and find?

To address this gap, we developed the meibomian gland composite score (MGCS), a standardized grading system that evaluates oil consistency and expressibility across individual eyelid glands using detailed visual guide photos and reference videos. We tested the system by reviewing clinical data from 53 patients. Statistical analysis confirmed that the MGCS accurately identified eyes with rapid tear evaporation, thus creating a reliable indicator of meibomian gland dysfunction.

What do these results mean?

The MGCS provides clinicians and researchers with a precise, reproducible method for evaluating eyelid gland health. By converting qualitative oil observations into a standardized numeric scale, this tool enhances clinical decision-making, improves patient tracking over time, and supports more robust clinical trials for new dry eye therapies.

Introduction

There are two primary forms of dry eye disease (DED): aqueous deficient and evaporative DED.¹ About 80% of all DED is evaporative in nature, with a key indicator of evaporative DED being a fast tear break up time (TBUT).² Meibomian dysfunction (MGD) is the most common cause of evaporative DED with MGD affecting between 3.5% and 69.3% of the population.³ As defined by the Tear Film and Ocular Surface Society, MGD results from “a chronic, diffuse abnormality of the meibomian glands, commonly characterized by terminal duct obstruction and/or qualitative/quantitative changes in glandular secretion”.⁴ Diagnosis of MGD is dependent on evaluation of meibomian gland health and functioning via clinical assessment of the quality and expressibility of meibum from the meibomian glands.⁵

Upper eyelids have between 30 and 40 meibomian glands, while lower eyelids have between 20 and 40 meibomian glands.⁶ The meibomian gland orifices are located on the eyelid margin, which is about 2.5 mm wide.⁶ In healthy individuals the glands linearly run from this orifice to the top (distal end) of the tarsal plate,⁷ and Pucker et al (n = 112) found with digital analysis of meibography images, that the upper eyelid meibomian glands have a mean width of 0.45 ± 0.08 mm while the lower eyelid meibomian glands have a mean width of 0.61 ± 0.11 mm.⁸ The gland orifices themselves can sometimes be challenging to see in healthy individuals, though obstructed glands are often easily visualized since caps form over the gland openings.⁵ The orifices are typically located just anterior to the mucocutaneous junction.⁶

While many grading systems have been proposed to evaluate MGD, there is no universally accepted or standardized system in clinical practice or research. Current scales vary in terms of the number of glands assessed, the pressure applied during expression, how meibum secretions are described, and how meibum quality is scored. This inconsistency complicates the ability to monitor disease progression or compare outcomes across studies.

To address these limitations, we propose a new grading system: the Meibomian Gland Composite Score (MGCS). This novel system integrates existing grading scales and introduces standardized procedures for evaluating expressibility and meibum quality using both upper and lower eyelids. Video examples are provided to further support consistent grading (Supplementary Videos 1, 2, 3, 4, and 5). Establishing a standardized, linear grading scale is critical because it enables eye care providers to detect subtle changes in disease severity over time, standardizes diagnostic thresholds, and improves comparative accuracy across clinical trials.

Scales Background

Meibomian gland expression is the key method for evaluating meibum quality and expressibility. It is performed by having the patient seated at the slit-lamp biomicroscope and viewing the eyelid with medium to high magnification.^5,9 Meibomian gland expression is performed by having the clinician pushes on the eyelid near the eyelid margin.^5,10,11 The applied pressure should be done in a way that slightly evert the eyelid, so the examiner can better view the glands. The number of expressible glands is then counted and the quality of the meibum is graded. This same procedure can be performed on both the upper and lower eyelids.

Korb and Blackie introduced the Meibomian Gland Evaluator in 2008 in an attempt to standardize the pressure applied during meibomian gland expression.¹² Their handheld device (contact surface area = 38.95 mm²) applies a standard amount of pressure to about 8 meibomian glands simultaneously for 10 to 15 seconds to the eyelid margin during meibomian gland expression.¹² The applied force is equivalent to a forced blink (force = 1.25g/mm²).¹² While in theory this device should provide more consistent results, Jones et al failed to find a significant difference in grades between evaluating the meibomian glands with the Meibomian Gland Evaluator compared to just using the finger expression method.¹³

While there are several grading schemes, fewer expressible glands and thicker meibum typically get assigned worse grades. If meibum cannot be expressed, the gland is considered obstructed, and obstruction typically gets assigned the worst grade. Meibomian gland obstruction increases one’s chances of ocular discomfort.^12,14 Norn likewise found that low meibomian gland expressibility was associated with thinner lipid layers, suggesting that meibomian gland obstruction leads to symptoms through tear film instability and evaporative dry eye.⁵ A list of commonly used grading scales for meibum quality and expressibility is in Table 1 and Table 2. The Tear Film and Ocular Surface Society suggests using a composite score for grading expressibility/meibum quality of the central 8 meibomian glands.¹⁵ Thus, if a 0 to 3 meibum quality scale (Shimazaki et al 1998) is applied to the central 8 meibomian glands, a composite score will range from 0 to 24 with 24 being the worst possible grade.^15,16 Unfortunately, TFOS’ method lacks sufficient detail to guide clinical assessment.

Table 1.

Meibum Quality Grading Scales

Scale	Grade Description
Grade	0	1	2	3	4
Bron et al 19916	Clear (Normal)	Cloudy	Granular	Inspissated/Solid	N/A
Mathers et al 199111	N/A	Clear	Relatively Clear	Opaque with Normal Viscosity	Toothpaste Like
Shimazaki et al 199816	Clear Meibum/Easily Expressed	Cloudy Meibum/Mild Pressure	Cloudy Meibum/Moderate Pressure	Meibum Not Expressible/Hard Pressure	N/A
Meadows et al 20129	Clear (Normal)	Granular Meibum	Whitish Semisolid Meibum	Yellow Solid Meibum	No Meibum Expressed

Table 2.

Meibomian Gland Expressibility Grading Scales

Scale	Grade Description
Grade	0	1	2	3
Bron et al 19916	All Expressed	1-2 Plugged	3-4 Plugged	5+ Plugged
Pflugfelder 1998 (5 Lower Glands)17	All Expressed	3-4 Expressed	1-2 Expressed	None
Foulks and Bron 200318	Minimal Pressure	Light Pressure	Moderate Pressure	Heavy Pressure
Meadows et al 2012 (Central 8 Glands)9	≥4 Expressed (Normal)	3 Expressed (Mild)	2 Expressed (Moderate)	≤1 Expressed (Severe)

Early work from Norn (n = 274) found that he was able to obtain meibum from an average of 10 glands per lower eyelid (range 0 to 23) in normal participants; the number of expressible glands decreased with age.⁵ Korb and Blackie (n = 133) similarly found that minimally symptomatic patients had a mean of 6.25 ± 0.35 expressible meibomian glands on the lower eyelid while patients with severe symptoms had a mean of 4.14 ± 0.56 expressible meibomian glands for the lower eyelid (central 8 glands).¹² Meadows et al (n = 43) later evaluated meibum expressibility (central 8 glands) with the Meibomian Gland Evaluator, and they found that the mean number of expressible glands at visit one in the normal group was 3.62 ± 1.80 while it was 3.54 ± 1.61 at visit two; there was a weighted κ of 0.3, which Meadows et al indicated was fair repeatability (intra-examiner).⁹ The mean number of expressible glands for the dry eye group was 1.53 ± 1.28.⁹ Meadows et al found that when a cut-point of ≥3 expressible glands was used there was a sensitivity of 83.3% and specificity 83.3% for differentiating between normal and dry eye participants (area under the curve = 0.84).⁹ Meadows et al then used these data to propose the 4-3-2-1 meibum expressibility grading scale, which indicated that ≥4 expressible glands was normal, 3 expressible glands was mildly reduced, 2 expressible glands was moderately reduced, and ≤1 expressible gland was severely reduced.⁹ While Meadows et al’s work was an advancement in the field, their expressibility grading method is a Likert‑like scale, which makes it challenging to linearly evaluate meibomian gland health grades, which makes it more challenging to track disease progression.

Methods

Although the literature provides detailed scales for evaluating meibomian gland expressibility and meibum quality, there is currently no sufficiently detailed scale for consistently assessing meibomian gland health in clinical practice or clinical trials. Therefore, the authors are proposing the following scale based upon the Tear Film and Ocular Surface Society’s guidance and past work.^9,15

Expression is performed by applying manual finger pressure near the eyelid margin, slightly everting the lid to optimize visualization of the central meibomian glands.^5,10,11 The central 8 upper eyelid meibomian glands should be evaluated, and the central 5 lower eyelid meibomian glands should evaluated, which is about the same amount of eyelid area given that the meibomian glands on the lower eyelids are wider than those in the upper eyelids.⁸ Evaluation of only the central glands on the upper and lower eyelids was incorporated into the grading system based upon precedence in the literature, the recommendation of The Tear Film and Ocular Surface Society, and because it is not feasible in clinic to evaluate every gland (eg, clinician time, patient comfort).^9,15 While the number of expressible glands does vary across the eyelid (nasal = most likely to express; central = intermediate likelihood of expressing; temporal = least likely to express),¹² the proposed method provides a balance between feasibility and an approach that can be consistently applied by the clinician while also capturing a representative number of meibomian glands. While evaluating, each graded gland should be assigned a meibum quality score based upon Figure 1. The grades for each meibomian gland for the upper eyelid should be summed (8 glands x maximum score of 4 for each gland = score range of 0 to 32 units), and the grades for each meibomian gland for the lower eyelid should be summed (5 glands x maximum score of 4 for each gland = score range of 0 to 20 units). Figure 1 and Supplementary Videos 1, 2, 3, 4, and 5 illustrate meibum quality across grades 0 to 4; reviewing these dynamic video reference examples ensures consistent scoring. For our scale, meibum texture—specifically its consistency and expressibility—is emphasized over color, as texture has been correlated with tear film stability and ocular surface staining, whereas color, though linked to lipid composition, has not shown a direct association with clinical signs.^19–21

Figure 1.

Meibomian Gland Composite Scale (MGCS), a 5-point scale (grades 0–4) used to evaluate meibum quality based on texture and expressibility. Representative images illustrate each grade. Red arrows indicate expressible meibum secretions at the meibomian gland orifices or attempted expression sites.

Clinical Validation

Ethics approval and consent to participate: This study was approved by the Colorado Multiple Institutional Review Board (COMIRB #19-0595). The study was conducted in accordance with the ethical principles of the Declaration of Helsinki. Given the retrospective nature of the study and its exempt status, the requirement for informed consent was waived. A retrospective chart review was conducted to evaluate the clinical performance and applicability of the MGCS in human patients. We reviewed 53 cases in which the MGCS had been used by two trained, independent providers between September 1, 2025, and December 15, 2025. Patients of any MGD severity were eligible, and they were identified based upon a search of the electronic medical records system for the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code H02.88 for meibomian gland dysfunction. The only exclusion criterion was incomplete data, and no exclusions were made based on ocular comorbidities or prior treatments. Patient data confidentiality was strictly maintained in accordance with HIPAA guidelines, and all data were de-identified prior to analysis.

The following data elements were required for inclusion:

• MGCS OD: right upper eyelid (UL) and right lower eyelid (LL) score

• MGCS OS: left UL and left LL score

• Tear breakup time (TBUT) for OD and OS

• Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire score

All patients underwent a consistent testing protocol that was pre-determined by the clinic director. This protocol included the SPEED, which was offered to every patient at the start of the exam. TBUT was measured by instilling 1 drop of saline onto a fluorescein strip and lightly touching the strip to the palpebral conjunctiva of the lower eyelid. The cobalt blue filter was then turned on, and the patient was instructed to blink three times. TBUT was recorded as the number of seconds from the final blink until the first disruption of the tear film, identified by the appearance of one or more dark spots within the fluorescein-stained tear film. MGCS was based upon the method described above. Data analysis was completed with non-parametric receiver operator characteristic (ROC) curves. TBUT values were used as an indicator of evaporative DED. TBUT scores ≤5 seconds were considered diseased, while TBUT values >5 seconds were considered normal.^22–24 TBUT scores were then used in the receiver operating characteristic (ROC) curve analysis to determine the MGCS score with the highest predictive value for each eyelid.

Included patients had a mean ± standard deviation age of 60.9 ± 16.4 years, and 75.5% of patients identified as female. All but two patients had abnormal SPEED scores (mean score = 14.40 ± 6.17) as signified by a score ≥3.²⁵ Right upper eyelids yielded a MGCS score of 22.78 ± 7.38 in the abnormal TBUT group and a score of 4.67 ± 5.78 in the normal TBUT group. Right lower eyelids yielded a MGCS score of 13.50 ± 4.27 in the abnormal TBUT group and a score of 3.71 ± 5.33 in the normal TBUT group. Left upper eyelids yielded a MGCS score of 20.51 ± 8.58 in the abnormal TBUT group and a score of 5.25 ± 6.88 in the normal TBUT group. Left lower eyelids yielded a MGCS score of 11.97 ± 5.83 in the abnormal TBUT group and a score of 5.56 ± 6.43 in the normal TBUT group.

Analysis of right upper eyelids (0.9539), right lower eyelids (0.9182), and left upper eyelids (0.9105) yielded a highly predictive area under the curves (AUC) in the ROC curve analysis, while left lower eyelid (0.7779) yielded a moderately predictive AUC in ROC curve analysis (Figure 2).²⁶ The likely reason for the weaker predictive values for the left lower eyelid was because there was a smaller range of MGCS scores for the left lower eyelid. The ROC curve analysis suggests that a score of 10 units on the MGCS scale would be a reasonable cut point for any eyelid for an abnormal score when trying to diagnose evaporative DED (Table 3).

Figure 2.

Receiver Operating Characteristic (ROC) Curves by Eyelid. (A) Right Upper Eyelid; (B) Right Lower Eyelid; (C) Left Upper Eyelid; (D) Left Lower Eyelid.

Figure 2.

Continued.

Table 3.

Receiver Operating Characteristic (ROC) Analysis Results by Meibomian Gland Composite Score (MGCS) Score

MGCS Score	Sensitivity (%)	Specificity (%)	Correctly Classified (%)
Right Upper Eyelid
8	96.88	76.19	88.68
10	93.75	85.71	90.57
11	93.75	90.48	92.45
13	90.62	90.48	90.57
Right Lower Eyelid
6	96.88	76.19	88.68
7	96.88	85.71	92.45
8	96.88	90.48	93.34
9	81.25	90.48	84.91
Left Upper Eyelid
8	89.19	68.75	83.02
10	83.78	68.75	79.25
11	83.78	75.00	81.13
12	81.08	75.00	79.25
Left Lower Eyelid
5	86.49	56.25	77.36
8	81.08	62.50	75.47
9	70.27	75.00	71.70
10	67.57	81.25	71.70

Discussion

The MGCS provides a more comprehensive and standardized method for grading MGD severity. Unlike previous scales, it accounts for gland-by-gland variation and includes both upper and lower eyelids. Its linear design makes it particularly useful for tracking disease progression and evaluating therapy response. By incorporating a 0–4 scale for each gland and summing across multiple glands, MGCS offers a wide scoring range and enhanced sensitivity.

The MGCS was developed using insights and guidance from several previously published grading scales. These existing frameworks—particularly those by Meadows et al, Shimazaki et al, and the Tear Film and Ocular Surface Society guidelines—informed the structure, grading approach, and evaluation techniques used in the MGCS system.^2,9,27 While the authors have built on their contributions, the revised meibum description provides greater clarity to differentiate between glandular secretion types. The authors also include a score of 4 to designate glands that yield no secretion—an important distinction not captured in some prior grading systems, which may compromise interpretation of MGD severity.

To enhance consistency and reproducibility across clinicians and researchers, Figure 1 and Supplementary Videos 1, 2, 3, 4, and 5 provide visual examples of grades 0–4. The MGCS has been successfully implemented and validated in human patients, and Table 4 further illustrates how it is applied to score the upper and lower eyelids and calculate the total composite score in a real-world setting. Validation likewise included a ROC curve analysis, which found that an eyelid score ≥10 is a good predictor of gland dysfunction that results in evaporative DED. These resources aim to standardize implementation, minimize grading variability, and create a standard for determining if a patient has a clinically meaningful level of gland dysfunction. The decision to assess 8 glands on the upper eyelid and 5 glands on the lower eyelid was based on anatomical considerations discussed in the Introduction as well as several other factors discussed in the Methods section. While the upper eyelids typically contain 30–40 glands, and the lower eyelids contain 20–40 glands, evaluating all glands is impractical due to time constraints and patient comfort. Instead, selecting a representative subset of glands balances feasibility and clinical relevance based on prior grading systems.

Table 4.

Example of Meibomian Gland Composite Score (MGCS) Grading

	Upper Eyelid Grade (8 Glands)	Upper Eyelid Score (0–32)	Lower Eyelid Grade (5 Glands)	Lower Eyelid Score (0–20)	Total Score (0–52)
Patient A	1, 0, 1, 2, 0, 1, 1, 0	6	0, 1, 0, 1, 1	3	9
Patient B	2, 1, 2, 1, 2, 0, 1, 1	10	1, 1, 1, 0, 1	4	14
Patient C	3, 2, 2, 2, 3, 2, 1, 2	17	2, 2, 1, 2, 1	8	25
Patient D	3, 3, 2, 4, 3, 4, 2, 3	24	3, 3, 2, 3, 2	13	37
Patient E	4, 4, 3, 4, 4, 4, 3, 4	30	4, 4, 3, 4, 4	19	49

While the MGCS builds on established grading systems and incorporates elements from previously validated scales, future studies should still examine its inter- and intra-grader repeatability. Given its foundation in existing methods, the MGCS is expected to be at least as reliable and reproducible as prior approaches. This system aims to provide a practical and comprehensive tool for assessing meibomian gland health in both clinical and research settings.

Funding Statement

Work was supported in part by an Unrestricted Grant to the CU Anschutz Department of Ophthalmology from Research to Prevent Blindness.

Ethics Approval and Consent to Participate

This study was approved by the Colorado Multiple Institutional Review Board (COMIRB #19-0595). The study was conducted in accordance with the ethical principles of the Declaration of Helsinki. Given the retrospective nature of the study and its exempt status, the requirement for informed consent was waived. Patient data confidentiality was strictly maintained in accordance with HIPAA guidelines, and all data were de-identified prior to analysis.

Disclosure

The authors have received research support from Abbvie Pharmaceuticals (ADP), Alcon Research, LLC (ADP), Bausch + Lomb (ADP), and Topcon (ADP). The authors have served as consultants for Abbvie (KSA), Alcon (KSA), Azura (KSA), Bausch + Lomb (ADP, KSA), BRIM (ADP), Dompe (KSA), HanAll Biopharma (ADP), Harrow (KSA), Mintra Health (ADP), Lexitas Pharma Services (ADP), Orasis Pharmaceuticals (ADP), Tarsus (KSA, AAT), and Lumenis (AAT). Dr. Pucker is the owner of Eminent Ophthalmic Services, LLC and an employee of Mintra Health and Electric Indigo; none of these companies have a financial interest in the topic of this paper. The authors report no other conflicts of interest in this work.