Detection of early visual field loss in glaucoma using frequency-doubling perimetry and short-wavelength automated perimetry.

OBJECTIVE

To investigate whether frequency-doubling perimetry (FDP) predicts future visual field loss with achromatic automated perimetry (AAP), just as it may be predicted with short-wavelength automated perimetry (SWAP).

METHODS

We recruited 62 patients selectively from an urban glaucoma practice. At the commencement of the study, each patient had ocular hypertension with normal visual fields on AAP. Baseline SWAP and FDP were performed to determine whether underlying earlier visual field loss was present. Patients were then followed up prospectively for 3 years with annual AAP, SWAP, and FDP. Main Outcome Measure The development of visual field loss on AAP.

RESULTS

Nine subjects had abnormal SWAP findings and 10 had abnormal FDP findings. At the conclusion of the study, field loss on AAP developed in 5, all of whom had preexisting abnormal SWAP and FDP results. No AAP visual field loss developed in patients with a normal SWAP or FDP. The rate of development of visual field loss on AAP was therefore significantly greater for those with abnormal SWAP (chi21 = 40.83; P<.001) and abnormal FDP findings (chi21 = 32.76; P<.001) than for those with normal SWAP and FDP findings.

CONCLUSION

In the same way that SWAP may predict AAP visual field loss, FDP may also detect field loss earlier than AAP.