Visual Field Defect Estimation Using Sequentially Optimized Reconstruction Strategy on Healthy and Glaucoma Subjects

Insel Gruppe AG, University Hospital Bern103 enrolled

Overview

Perimetry is a well-established method that is used to measure the visual field functions of humans. Commercially available products, such as the OCTOPUS 900 (Haag-Streit AG, Koeniz, Switzerland), are commonly used for assessing the visual field. Such devices are of critical value for patients suffering of glaucoma and neuro-ophthalmic conditions. The operating principle is to sequentially present light stimuli of different intensity at different locations within the visual field in an automatic way. Algorithms that select what locations and intensities to present over time are called strategies. These have the goal to provide both a fast and accurate estimation of the visual field function. Recently, new strategies were developed that are faster and equally accurate as the strategies used today. The technological advancement of these new methods lies primarily in the ability to estimate location sensitivities without observing them directly but by leveraging previously queried locations. For this the investigators plan to implement the next generation of perimetry strategies into an OCTOPUS 900 and to test it in healthy subjects and glaucoma patients.

Study Type

OBSERVATIONAL

Enrollment

103

Conditions

Glaucoma, Open-Angle

Interventions

Visual field testing

Standard Automated Perimetry using a perimeter is one of the most commonly used techniques for measuring perceived visual ability of a subject. For a given eye, it provides quantitative measurements of visual function represented as a 2D spatial visual field map. It is of great clinical importance for diagnosing and monitoring glaucoma and detecting neurological conditions.

Eligibility

Sex: ALLMin age: 40 YearsMax age: 80 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Cataract yes or no * Age range 40 - 80 years * Normal visual field (MD: \< +2 dB) * Refractive error within ±5 dpt. spherical equivalent * Astigmatism of \< -3 dpt. * Visual acuity of ≥0.3 logMar (decimal ≥0.5) * Experience in perimetry (history of at least one perimetry examination) * False positive or negative errors each less than 20% in each examination * Primary open-angle/ pseudoexfoliation/ primary angle-closure glaucoma * Early to moderate visual field loss (MD: +2 to +12 dB) * Written informed consent Exclusion Criteria: Exclusion criteria are children (\<18 years old), inability to follow the procedure, insufficient knowledge of project language, the history of other ocular diseases than glaucoma or cataract or other conditions that might affect visual field testing (e.g. pituitary lesions, demyelinating diseases).

Outcomes

Primary Outcomes

Non-inferiority estimation quality of mean defect between SORS and dynamic strategy visual field locations

The primary endpoint of this study is the non-inferiority estimation quality of mean defect when using SORS visual field locations as compared to the dynamic strategy visual field locations in healthy subjects and glaucoma patients with early or moderate visual field loss. The non-inferiority margin is defined as a mean defect difference of no more than 0.5 decibel to the dynamic strategy measurement.

Time frame: 12 months