Study of Corneal Biomechanics in Glaucoma Patients Using Brillouin Microscopy

Not yet recruiting

• Conditions: Glaucoma
• Interventions: Drug: Prostaglandin Analogue -Containing IOP-Lowering Therapy; Drug: Beta Blocker; Device: Brillouin Microscopy

• Registration Number: NCT06993597
• Lead Sponsor: University of Maryland, Baltimore

Brief Summary

This pilot study evaluates the biomechanical properties of the cornea in glaucoma patients using Brillouin microscopy, a non-contact imaging technique. The study aims to compare corneal stiffness between patients with normal-tension glaucoma, high-tension glaucoma, and healthy controls, and to assess changes in corneal biomechanics following intraocular pressure (IOP)-lowering treatment. The goal is to determine whether Brillouin-derived biomechanical measurements can serve as biomarkers for glaucoma risk and progression.

Detailed Description

This study explores the biomechanical properties of the cornea in patients with glaucoma using a novel, non-contact imaging technique called Brillouin microscopy. The technology allows in vivo assessment of tissue stiffness without physical perturbation, potentially offering new insights into glaucoma risk and response to therapy.

The study includes two parts: a cross-sectional comparison between patients with normal- and high-tension glaucoma and healthy controls, and a longitudinal analysis of biomechanical changes following IOP-lowering treatment with either prostaglandin analogs or beta blockers.

The goal is to determine whether corneal biomechanics can serve as a biomarker for glaucoma susceptibility and progression, and to evaluate the feasibility of integrating Brillouin imaging into clinical glaucoma care.

Study Timeline

• Status Verified: 2025-05
• Study First Submitted: 2025-05-19
• Study First Submitted QC: 2025-05-19
• Last Update Submitted: 2025-05-19
• Study First Posted: 2025-05-29
• Last Update Posted: 2025-05-29
• Study Start: 2025-06
• Primary Completion: 2026-03
• Study Completion: 2026-06

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

• Age 18 years or older

Diagnosis of primary open angle glaucoma (POAG) or no history of glaucoma (for controls)

Open angle on gonioscopy (Shaffer grade 3 or 4)

Best-corrected visual acuity of 20/25 or better

Refractive error between +3.00 and -5.00 diopters

No prior use of topical glaucoma medications

Diagnosis of:

High Tension Glaucoma (IOP ≥ 22 mmHg on 3 visits)

Normal Tension Glaucoma (IOP ≤ 21 mmHg on 3 visits)

OR age-matched control with normal optic nerve and visual fields

Exclusion Criteria

Corneal abnormalities or conditions interfering with Brillouin or applanation tonometry

Retinal diseases affecting RNFL (e.g., macular traction)

History of ocular surgery or laser

Diagnosis of diabetes

History of uveitis

History of prolonged steroid use

Neurodegenerative or systemic diseases (e.g., multiple sclerosis, Alzheimer's, Parkinson's, schizophrenia)

Unreliable visual fields

Contraindications to beta blockers (e.g., bradycardia, severe pulmonary disease)

Moderate to severe glaucoma (per Hodapp-Anderson-Parrish criteria)

History of contact lens use

Low blood pressure

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Normal Tension Glaucoma	Prostaglandin Analogue -Containing IOP-Lowering Therapy	Newly diagnosed, treatment-naïve subjects with normal tension glaucoma. Brillouin imaging will be performed at baseline, and in a subset receiving IOP-lowering therapy, additional imaging will be performed at 3 and 6 weeks.
Normal Tension Glaucoma	Beta Blocker	Newly diagnosed, treatment-naïve subjects with normal tension glaucoma. Brillouin imaging will be performed at baseline, and in a subset receiving IOP-lowering therapy, additional imaging will be performed at 3 and 6 weeks.
Normal Tension Glaucoma	Brillouin Microscopy	Newly diagnosed, treatment-naïve subjects with normal tension glaucoma. Brillouin imaging will be performed at baseline, and in a subset receiving IOP-lowering therapy, additional imaging will be performed at 3 and 6 weeks.
High Tension Glaucoma	Prostaglandin Analogue -Containing IOP-Lowering Therapy	Newly diagnosed, treatment-naïve subjects with high tension glaucoma. Brillouin imaging will be performed at baseline, and in a subset receiving IOP-lowering therapy, additional imaging will be performed at 3 and 6 weeks.
High Tension Glaucoma	Beta Blocker	Newly diagnosed, treatment-naïve subjects with high tension glaucoma. Brillouin imaging will be performed at baseline, and in a subset receiving IOP-lowering therapy, additional imaging will be performed at 3 and 6 weeks.
High Tension Glaucoma	Brillouin Microscopy	Newly diagnosed, treatment-naïve subjects with high tension glaucoma. Brillouin imaging will be performed at baseline, and in a subset receiving IOP-lowering therapy, additional imaging will be performed at 3 and 6 weeks.
Control	Brillouin Microscopy	Age-matched healthy control subjects with no history of glaucoma or IOP-lowering therapy. Brillouin imaging will be performed at a single time point for cross-sectional comparison.

Primary Outcome Measures

Name	Time	Method
Change in Corneal Biomechanical Modulus	Baseline, 3 weeks, and 6 weeks	Brillouin microscopy will be used to measure the corneal modulus of elasticity. The primary outcome is the change in corneal stiffness (Brillouin shift in MHz) across time points in subjects treated with prostaglandin analogs versus beta blockers, and between groups at baseline (NTG, HTG, controls).

Trial Locations

Locations (1)

University of Maryland School of Medicine; 🇺🇸 Baltimore, Maryland, United States