Reproducibility of Blood Flowmetry in Human Retina Using the Nidek Laser Speckle Flowgraphy LSFG-NAVI System

Completed

• Conditions: Healthy; Normal Tension Glaucoma; Open Angle Glaucoma
• Interventions: Diagnostic Test: LASER SPECKLE FLOWGRAPHY

• Registration Number: NCT04014933
• Lead Sponsor: University of Zurich

Brief Summary

In addition to intraocular pressure blood perfusion pressure in the optic nerve is an important factor determing the cause of glaucoma. Increasing evidence suggests that in glaucoma patients retinal blood may be decreased.

Detailed Description

According to the World Health Organization (WHO) glaucoma is the second leading cause of blindness. Glaucoma is a global problem, which is becoming even more important as the human life expectancy increases. Although the causes of glaucoma are uncertain, mainly intraocular pression (IOP), genetics, and ocular blood perfusion pressure in the optic nerve determine the cause of the disease. Increasing evidence suggests that in glaucoma patients retinal blood flow is decreased leading to progression and to damage of the optic nerve.

In order to measure the peripapillary blood flow a variety of devices using different techniques of flowmetry have been developed. In this study, the reproducibility of the retinal flowmetry measured with the LSFG-NAVI device from Nidek will be investigated. A high reproducibility is crucial for the clinical value of any measuring device.

Study Timeline

• Study Start: 2019-07-01
• Study First Submitted: 2019-07-03
• Study First Submitted QC: 2019-07-08
• Study First Posted: 2019-07-10
• Primary Completion: 2021-02-09
• Study Completion: 2021-12-31
• Status Verified: 2023-06
• Last Update Submitted: 2023-06-01
• Last Update Posted: 2023-06-05

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 44

Inclusion Criteria

• signed Patient Informed Consent form
• Be at least 18 years old
• Diagnosis of primary or secondary open-angle glaucoma or normal tension glaucoma or healthy controls

Exclusion Criteria

• Age < 18 years
• Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant.
• No vulnerable participants will be included in this study.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
healthy controls	LASER SPECKLE FLOWGRAPHY	individuals with normal optic disc and IOP \</21mmHg and normal visual fields
normal tension glaucoma	LASER SPECKLE FLOWGRAPHY	patients with a diagnosis of normal tension glaucoma, i.e. untreated IOP \</=21mmHg plus glaucomatous disc changes and/or visual field defects typical for glaucoma
open-angle glaucoma	LASER SPECKLE FLOWGRAPHY	patients with a diagnosis of open-angle glaucoma, i.e. untreated IOP \>21mmHg plus glaucomatous disc changes and/or visual field defects typical for glaucoma

Primary Outcome Measures

Name	Time	Method
intraclass correlation coefficients (ICCs)	1 month	Intraobserver ICC, interobserver ICC, and inter-session ICC will be computed
Coefficients of variation (COV)	1 month	COVs from 3 measurements of ocular blood flow at visit 1 of observer 1 and at visit 1 of observer 1 and from observer 2 will be computed.

Secondary Outcome Measures

Name	Time	Method
Cofounder	1 month	intraocular pressure will be checked as potential cofounder

Trial Locations

Locations (1)

Department of Ophthalmology; 🇨🇭 Zurich, ZH, Switzerland