The Relationship Between Visual Acuity and the Reproducibility of Visual Field Measurements in Glaucoma Patients

The purpose of this study was to investigate the association between visual acuity (VA) and reproducibility of test-retest visual field (VF) measurements in glaucoma patients.

Subjects were comprised of 627 eyes of 627 open-angle glaucoma patients. The reproducibility of two Humphrey VFs (24-2 or 30-2 Swedish Interactive Threshold Algorithm tests) examined twice within the period of 3 months was calculated using the root mean squared error (RMSE) of each VF test point's sensitivity. Visual acuity was measured once at the time of either of the VF measurements. Linear modeling was used to investigate the relationship between reproducibility of VF tests (RMSE) and the following variables: mean total deviation value (mTD), fixation losses (FLs), false positives (FPs), false negatives (FNs), refractive error, age, and VA.

The optimal model to predict test-retest variability (RMSE) of VFs included age, VA, mTD, and FNs as dependent variables. Root mean squared error was significantly larger in eyes with logMAR VA > 0.5 than in eyes with logMAR VA ≤ 0.

Reproducibility of VF tests becomes poor with the deterioration of VA. Careful consideration is needed when a patient's logMAR VA exceeds 0.5.