Assessment of Endothelial Glycocalyx in Patients With Primary Open-angle Glaucoma (GLAUCALYX)

Assessment of Endothelial Glycocalyx in Patients With Primary Open-angle Glaucoma: a Prospective Single-center Cross-sectional Case-control Study

The glycocalyx is a fibrillary lining structure that covers the inner surface of blood vessels. Composed of glycoproteins and polysaccharides, it is an essential determinant of vascular endothelial physiology: it limits coagulation activation and adapts capillary perfusion. Studies have shown glycocalyx alteration in various vascular and autoimmune pathologies such as diabetes, high blood pressure, chronic renal failure, ischemic heart disease, stroke, dementia, septic shock, and several other inflammatory pathologies with a common basis in vascular insufficiency.

Glaucoma is a progressive, chronic and asymptomatic optic neuropathy characterized by visual field damage and abnormalities of the optic nerve head. Two hypotheses have been proposed as a basis for this progressive damage:

• the mechanical theory, which explains the papillary excavation by a compression of the optic nerve head under the effect of high intraocular pressure; and
• the ischemic theory, explained by a circulatory insufficiency at the level of the blood capillaries of the retina and especially of the optic nerve head. This latter theory is related to several pathologies that have circulatory insufficiency as common underlying pathophysiology, and in which damage to the glycocalyx has been well studied.

Glycocalyx damage has rarely been studied in glaucoma. Yang et al. showed that the glycocalyx, present in Schlem's canal, plays a major role in the transduction of shear stress and regulation of outflow resistance to the aqueous humor, which may constitute an interesting biomarker for glaucomatous pathologies.

Study Overview

• Status: Recruiting
• Conditions: Glaucoma; Primary Open-angle Glaucoma
• Intervention / Treatment: Procedure: Glycocheck; Procedure: Ophthalmological examinations

Detailed Description

This study propose to extend the exploration of the ischemic theory of glaucoma by a specific imaging technique (the GlycoCheck) which allows an assessment of the microvascular system integrity by giving a "vitality score" of this system. This score, known as the MicroVascular Health score (MVHS), depends on the following measured parameters: Capillary density (CD), Red blood cell filling Percent (RBF), and Perfused boundary region (PBR).

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Amélie YAVCHITZ, MD; Phone Number: 01 48 03 64 33; Email: ayavchitz@for.paris

Study Locations

• France
  • Paris, France, 75019
    • Recruiting
    • Hôpital Fondation A. de Rothschild
    • Contact: Cédric LAMIREL; Email: clamirel@for.paris
    • Contact: Georges AZAR; Email: gazar@for.paris

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Case group: patients with primary open angle glaucoma Control group : patient with no optic nerve pathology, matched with patients in case group on age (± 10 years), sex (male/female), and smoking status (active smoker/non-smoker or non-smoker or former smoker who had quit smoking for more than 6 months).

Description

Inclusion Criteria:

• Express consent to participate in the study
• Only for case group: primary open angle glaucoma (defined as the presence of visual field damage attributed to glaucomatous optic neuropathy) in both eyes
• Only for control group: Absence optic nerve pathology (including primary open angle glaucoma)

Exclusion Criteria:

• Pregnant or breastfeeding woman
• Sleep apnea
• Renal insufficiency
• Parkinson's disease
• Alzheimer's disease
• Antiphospholipid syndrome
• Cancer for which treatment ended less than 2 years ago
• Stroke less than 1 year ago
• Myocardial infarction less than 1 year ago

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Case group: primary open angle glaucoma	Procedure: Glycocheck; Assessment of the sublingual microvascularization; Procedure: Ophthalmological examinations; Description : Measurement of best corrected distance visual acuity with ETDRS (Early Treatment Diabetic Retinopathy Study) Measurement of intraocular pressure by aplanation and forced air tonometer Central corneal thickness measurement with OCT (Optical Coherence Tomography) Non-mydriatic retinophotography Humphrey 24-2 visual field OCT-RNFL (Optical Coherence Tomography - retinal nerve fiber layer)
Control group: No Absence of optic nerve pathology	Procedure: Glycocheck; Assessment of the sublingual microvascularization; Procedure: Ophthalmological examinations; Description : Measurement of best corrected distance visual acuity with ETDRS (Early Treatment Diabetic Retinopathy Study) Measurement of intraocular pressure by aplanation and forced air tonometer Central corneal thickness measurement with OCT (Optical Coherence Tomography) Non-mydriatic retinophotography Humphrey 24-2 visual field OCT-RNFL (Optical Coherence Tomography - retinal nerve fiber layer)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Thickness of the Perfused boundary region (PBR)	Evaluated with the Glycocheck, in µm	Baseline day

Collaborators and Investigators

• Sponsor: Fondation Ophtalmologique Adolphe de Rothschild
• Investigators: Principal Investigator: Cédric LAMIREL, MD, Hôpital Fondation A. de Rothschild; Study Chair: Georges AZAR, MD, Hôpital Fondation A. de Rothschild

Study record dates

Study Major Dates

• Study Start (Actual): May 6, 2022
• Primary Completion (Estimated): May 1, 2026
• Study Completion (Estimated): May 1, 2026

Study Registration Dates

• First Submitted: February 21, 2022
• First Submitted That Met QC Criteria: March 2, 2022
• First Posted (Actual): March 3, 2022

Study Record Updates

• Last Update Posted (Actual): December 8, 2025
• Last Update Submitted That Met QC Criteria: December 2, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Glaucoma; Glycocalyx; Primary Open-angle Glaucoma; Glycocheck; Sublingual microvascularization
• Additional Relevant MeSH Terms: Eye Diseases; Ocular Hypertension; Glaucoma; Glaucoma, Open-Angle
• Other Study ID Numbers: CLL_2021_27

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No