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Variability and Errors of Manually Digitized Goldmann Visual Fields.

Michael P Barry¹, Ava K Bittner, Liancheng Yang

¹*MS †OD, PhD, FAAO ‡BA §MD **PhD, FAAO Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland (MPB); College of Optometry, Nova Southeastern University, Ft. Lauderdale, Florida (AKB); and Department of Ophthalmology (LY, MHI, GD) and Department of Neuroscience, Johns Hopkins University, Baltimore, Maryland (RM).

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|April 9, 2016

Summary

This summary is machine-generated.

Digitizing Goldmann visual fields (GVFs) for inherited retinal degeneration is reliable, even with minimal training. Using five to seven digitizers can ensure accurate data capture for functional retina tracking.

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Area of Science:

Ophthalmology
Medical Imaging
Retinal Degeneration Research

Background:

Goldmann visual fields (GVFs) are crucial for monitoring functional retinal areas, particularly the periphery, in patients with inherited retinal degenerations.
Accurate quantitative analysis of GVFs necessitates the digitization of charted coordinates and isopter points.
Variability in manual digitization can impact the reliability of GVF data.

Purpose of the Study:

To investigate the inter- and intra-digitizer variability associated with a manual Goldmann visual field digitization program.
To assess the reliability of isopter area measurements performed by minimally trained digitizers.

Main Methods:

Ten digitizers underwent a 1-hour training session.
Each digitizer processed 23 GVFs from inherited retinal degeneration patients across three blocks.
Isopters were labeled as seeing or non-seeing, and their target sizes were recorded for analysis.

Main Results:

A square-root relationship was observed between the standard deviation of isopter group area and total isopter group area.
The coefficient of variation for isopter group area significantly decreased with increasing area, from 68% to 0.2%.
A bootstrap ANOVA indicated no significant effect of digitizers on isopter group area, suggesting high reliability.

Conclusions:

Minimally trained digitizers can reliably determine isopter areas of any size in GVFs.
Recommended strategies for studies include using five to seven digitizers per GVF, employing three pre-screened digitizers, or using two digitizers with an expert adjudicator.