Measuring the perimetric threshold in reduced retinal illumination using Elisar and Humphrey visual field Analyzer

Dr. Agarwal’s Eye Hospital Institutional Review Board

Chennai – 600018

PROJECT SUMMARY

Introduction: Glaucoma is the second leading cause of blindness in the world, affecting more than 60 million people globally.1 The differential light threshold is influenced by factors, such as the subject’s age, alertness, media clarity, ocular diseases, ocular medications, and systemic medications.2 Early Glaucomatous field loss will have a diffuse pattern in perimetry report.3

Elisar Visual Field Analyser is a portable device which can detect early glaucoma and can reduce the number of people affected with severe field loss.

By introducing Neutral Density Filter (NDF) and reducing the retinal illumination to understand the visual field loss in glaucomatous patients.

Objective: To measure the perimetric threshold in reduced retinal Illumination using Elisar and Humphrey Visual Field Analyser.

Study Design: Cross-sectional experimental study trial.

Methodology: All subjects will be performing 4 Elisar Visual Field Analyser examination and 4 Humphrey Visual Field Analyser examination with a series of Neutral Density Filter placed in front of the right eye. The subject will undergo Dilation process by instilling eye drop and closing the eye for 45 minutes. After the dilation, if the subject’s pupil,30 minutes of dark adaptation is given before the examination. After each examination, tropicamide will be instilled to maintain the dilation and also 30 minutes of dark adaptation.

Sample Size: 7 Normal Subjects

Inclusion Criteria:  Patients with age between 20–46 years, cycloplegic refractive errors,+0.75 to -2.25D of Spherical error and < -0.50D of astigmatic error.

Exclusion criteria: Patient with the presence of any media opacities or neurological diseases.

Expected Outcome: The ability of Elisar Visual Field Analyser to detect early glaucomatous visual field loss is similar to Humphrey Visual Field Analyser.

Duration: 2 months

Ethical Consideration: Waiting for Approval.

Reference:

1. Quigley HA, Broman AT. The number of people with glaucoma worldwide in 2010 and 2020.Br J Ophthalmol.2006;90:262–7.

2. Heuer, D. K., Anderson, D. R., Feuer, W. J., Knighton, R. W., Gressel, M. G., and Fantes, F. E.: The influence of simulated media opacities on threshold measurements. In Greve, E. L., and Heijl, A. (eds.): Proceedings of the 7th International Visual Field Symposium. Dordrecht, The Netherlands, Martinus Nijhoff/Dr. W. Junk Publishers, 1987, pp. 15-22.

3. Diffuse Loss of Sensitivity in Early Glaucoma

David B.Henson; Paul H.Artes; Balwantray C.Chauhan.