Effect of Micropulse Laser on Dry Eye Disease Due to Meibomian Gland Dysfunction

NCT04425551 | Completed

• 1 other identifier: 6/19
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 2

Brief Summary

The modern treatment of meibomian gland dysfunction(MGD) is based on anti-inflammatory drops or oral antibiotics for decreasing dry eye disease (DED) associated inflammation, warm compresses for liquefying the thicker meibum, and lid hygiene for reducing the bacterial overload. But, such treatments have shown limited effectiveness to a large proportion of patients with MGD, due to the multifactorial background of the disease. Thus, alternative approaches aiming at different aspects of the DED pathophysiology are needed. Elimination of posterior lid-margin hyperemia with telangiectasia could be a treatment target for reducing the secretion of inflammatory mediators in the course of MGD. Using the mechanism of photocoagulation via selective thermolysis, laser light could contribute to the destruction of abnormal vessels at the posterior lid-margin and thus, the reduction of inflammation. Recently, sub-threshold (micropulse) laser photocoagulation was introduced in ophthalmology and offers significant clinical advantages compared to conventional continuous wave (CW) approach, preventing laser induced thermal damage and related treatment side effects. This study investigates the effect of sub-threshold (micropulse) laser treatment for dry eye disease due to meibomian gland dysfunction combined with increased eyelid margin vascularity.

Conditions

Dry Eye; Dry Eye Syndromes; Meibomian Gland Dysfunction

Keywords

dry eye; meibomian gland dysfunction; subthreshold laser; telangiectasia; eyelid margin vascularity

Outcome Measures

Primary Outcomes (1)

• Tear Break Up Time (TBUT)

  Using a slit-lamp biomicroscope with cobalt blue illumination, the time interval between the last complete blink and first appearance of a dark dry spot on the corneal surface was measured using a digital stopwatch. The test was repeated three times consecutively, and the mean TBUT was recorded

  The subjects were evaluated at five different time points: (a) 1 day preoperatively (baseline), (b) 2 weeks (W2), (c) 4 weeks (W4), (d) 8 weeks (W8), and (e) 12 weeks (W12) postoperatively.

Secondary Outcomes (11)

• Ocular Surface Disease Index (OSDI)

  The subjects were evaluated at five different time points: (a) 1 day preoperatively (baseline), (b) 2 weeks (W2), (c) 4 weeks (W4), (d) 8 weeks (W8), and (e) 12 weeks (W12) postoperatively.

• Lower Eyelid Tear Meniscus Height

  The subjects were evaluated at five different time points: (a) 1 day preoperatively (baseline), (b) 2 weeks (W2), (c) 4 weeks (W4), (d) 8 weeks (W8), and (e) 12 weeks (W12) postoperatively.

• Lower Eyelid Tear Meniscus Depth

  The subjects were evaluated at five different time points: (a) 1 day preoperatively (baseline), (b) 2 weeks (W2), (c) 4 weeks (W4), (d) 8 weeks (W8), and (e) 12 weeks (W12) postoperatively.

• Meibomography

  The subjects were evaluated at five different time points: (a) 1 day preoperatively (baseline), (b) 2 weeks (W2), (c) 4 weeks (W4), (d) 8 weeks (W8), and (e) 12 weeks (W12) postoperatively.

• Best Corrected Visual Acuity (BCVA)

  The subjects were evaluated at five different time points: (a) 1 day preoperatively (baseline), (b) 2 weeks (W2), (c) 4 weeks (W4), (d) 8 weeks (W8), and (e) 12 weeks (W12) postoperatively

Other Outcomes (1)

• Posterior margin irregularity, hyperkeratosis, lash loss, anterior blepharitis, tear debris, and tear foam

  The subjects were evaluated at five different time points: (a) 1 day preoperatively (baseline), (b) 2 weeks (W2), (c) 4 weeks (W4), (d) 8 weeks (W8), and (e) 12 weeks (W12) postoperatively

Study Arms (2)

Laser Group

ACTIVE COMPARATOR

The treatment involved laser photocoagulation of the telangiectatic vessels of the lower eyelid margin with a slit lamp-based 532 nm optically pumped dual- diode solid-state subthreshold (SP-Mode) laser system (LightLas TruScan Pro 532 nm, LightMed Corporation, San Clemente, CA, USA). The laser settings were selected to induce vascular photocoagulation without visible tissue blanching or epithelial disruption. The subthreshold treatment parameters were set at 50 μm spot size and duration of 200 ms with duty cycle of 20%. Laser power was titrated in mono-spot micropulse mode starting at 500 mW and increased in 100 mW steps, until focal blanching without epithelial whitening, maximum 1500 mW. The treatment endpoint was defined as immediate focal blanching (disappearance of the red reflex) of the target telangiectatic vessel, assessed under a high-magnification slit-lamp view, with the effect confined to the targeted vessel and no visible impact on adjacent tissue.

Procedure: laser light

Control Group

PLACEBO COMPARATOR

Sham treatment replicated all procedural steps (eyelid eversion, stabilization, slit-lamp aiming, equivalent spot count) using identical laser settings, but with minimal power (50 mW, duration 10 ms) and beam offset to the adjacent non-vascular periorbital skin, ensuring no energy delivery to eyelid margin vessels, and preserving the device operational sound, laser light, and foot pedal activation. No laser energy was delivered to eyelid margin vasculature in the sham treatment, and no visible tissue reaction or blanching was observed during the procedure. The anesthesia and cleaning procedures were identical.

Device: Sham treatment

Interventions

laser light PROCEDURE

laser photocoagulation of the telangiectatic vessels of the lower eyelid margin with a slit lamp-based 532 nm optically pumped dual- diode solid-state subthreshold (SP-Mode) laser system

Laser Group

Sham treatment DEVICE

Sham treatment replicated all procedural steps (eyelid eversion, stabilization, slit-lamp aiming, equivalent spot count) using identical laser settings, but with minimal power (50 mW, duration 10 ms) and beam offset to the adjacent non-vascular periorbital skin, ensuring no energy delivery to eyelid margin vessels, and preserving the device operational sound, laser light, and foot pedal activation. No laser energy was delivered to eyelid margin vasculature in the sham treatment, and no visible tissue reaction or blanching was observed during the procedure. The anesthesia and cleaning procedures were identical.

Control Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• chief complaint of at least one of the following symptoms: dryness, foreign-body sensation, burning, and tearing for 3 months
• diagnosis of DED secondary to MGD with eyelid margin telangiectasias in both eyes
• a baseline Ocular Surface Disease Index (OSDI) score ≥ 40
• tear break-up time (TBUT) ≤ 5 seconds
• corneal fluorescein staining ≥ 6 as per the National Eye Institute (NEI) grading scale for corneal staining.

You may not qualify if:

• history of ocular trauma or surgery
• use of any treatment for DED or MGD other than artificial tears within the past 3 months
• active allergy, infection, or inflammatory disease at the ocular surface unrelated to DED or MGD
• lacrimal drainage system anomalies
• contact lens wear
• use of any systemic or topical anti-inflammatory medicine

Sponsors & Collaborators

• Naval Hospital, Athens: lead
• National and Kapodistrian University of Athens: collaborator

Study Sites (2)

Naval Hospital of Athens

Athens, 11521, Greece

Location

First Department of Ophthalmology, National and Kapodistrian University of Athens, Athens, Greece

Athens, Greece

Location

MeSH Terms

Conditions

Dry Eye Syndromes; Meibomian Gland Dysfunction; Telangiectasis

Interventions

Lasers

Condition Hierarchy (Ancestors)

Lacrimal Apparatus Diseases; Eye Diseases; Eyelid Diseases; Vascular Diseases; Cardiovascular Diseases

Intervention Hierarchy (Ancestors)

Optical Devices; Equipment and Supplies; Radiation Equipment and Supplies

Study Officials

• Nikolaos Kappos, MD

  Naval Hospital, Athens

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Ophthalmologist Surgeon, Clinical Investigator

Model Details: Please note that there was one group of participants, but two groups of eyes (treated/untreated). Thus, PARALLEL was selected, referring to eyes, not participants

Study Record Dates

• First Submitted: June 4, 2020
• First Posted: June 11, 2020
• Study Start: December 6, 2022
• Primary Completion: April 3, 2025
• Study Completion: July 18, 2025
• Last Updated: January 2, 2026

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

GR (2)