The effect of refractive error on automated global analysis program G-1

Area of Science:

• Ophthalmology
• Visual Science

Background:

• Accurate visual field testing is crucial for diagnosing and monitoring glaucoma.
• Refractive errors can influence visual field test results, potentially leading to misinterpretation.

Purpose of the Study:

• To investigate the impact of induced refractive errors on visual field indices obtained using the Octopus global analysis program G-1.
• To quantify how increasing ametropia affects the mean defect and other parameters.

Main Methods:

• Ten non-glaucomatous eyes underwent induced refractive errors after cycloplegia.
• Visual field testing was performed using the Octopus program G-1 with varying spherical corrections (+0.00 D, +1.00 D, +2.00 D).
• Key visual field indices, including mean defect, were analyzed.

Main Results:

• The lowest mean defect (2.4 +/- 0.8 dB) was observed with full cycloplegic correction.
• Increasing ametropia significantly elevated the mean defect: 3.6 +/- 0.8 dB with +1.00 D and 5.3 +/- 0.9 dB with +2.00 D (P < .0001).
• Corrected loss variance, skew, short-term fluctuation, and reliability factor showed no significant changes with refractive error variations.

Conclusions:

• Induced refractive errors, particularly ametropia, significantly degrade visual field mean defect values in Octopus G-1 analysis.
• These findings highlight the importance of precise refractive correction during visual field testing for accurate glaucoma assessment.
• Clinicians should ensure full refractive correction to avoid overestimation of visual field loss.