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

Sponsor

Fondation Ophtalmologique Adolphe de Rothschild (Other)

Overall Status

Recruiting

CT.gov ID

NCT05264818

Collaborator

(none)

100

Enrollment

Location

15.9

Anticipated Duration (Months)

6.3

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

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.

Condition or Disease	Intervention/Treatment	Phase
Primary Open-angle Glaucoma Glaucoma	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 Design

Study Type:

Observational

Anticipated Enrollment :

100 participants

Observational Model:

Case-Control

Time Perspective:

Prospective

Official Title:

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

Actual Study Start Date :

May 6, 2022

Anticipated Primary Completion Date :

Sep 1, 2023

Anticipated Study Completion Date :

Sep 1, 2023

Arms and Interventions

Arm	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)

Arm

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

Outcome Measures

Primary Outcome Measures

Thickness of the Perfused boundary region (PBR) [Baseline day]
Evaluated with the Glycocheck, in µm

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

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)