Abstract
Purpose:
To compare the performance of Heidelberg Edge Perimeter (HEP) Flicker-Defined Form (FDF) and Standard Automated Perimetry (SAP) strategies to Humphrey SAP, in terms of reliability, duration of test and agreement between tests.
Methods:
Consecutive new glaucoma suspects referred to a hospital’s glaucoma service received all 3 tests. A screening pre-test familiarised patients to the FDF stimulus followed by HEP-SAP and HEP-FDF tests. Agreement between tests was analysed using visual fields of patients with normal optic discs as judged by experienced optic disc graders using optic disc photographs.
Results:
137 patients (50 men, 57 women) with non-glaucomatous optic discs were included (average age, 61.1 years [SD, 9.9 years], range 22-89 years). 30 patients who performed unreliable HEP-FDF visual fields were excluded. Significantly lower values for test duration time compared to HFA-SAP (HEP-FDF: mean 276.3 seconds, SD 77.2 s; HEP-SAP: mean 214.9 s, SD 37.9 s; HFA-SAP: mean 307.1 s, SD 47.9 s). Among the reliability indexes, Fixation Losses were significantly fewer with the HEP-FDF (mean %, 1.19, SD 4.21; HEP-SAP: mean 5.21, SD 16.25; HFA-SAP: mean, 14.87, SD 23.69) . False Positive values (%) for HFA-SAP (mean 2.66; SD 4.62) were significantly higher than both HEP-FDF (mean 0.75; SD 1.17), or HEP-SAP (mean 0.79; SD 3.01). The mean False Negative ratios for HEP-FDF, HEP-SAP and HFA-SAP visual fields were 7.1 (SD 10.7), 3.9 (SD 8.0), 1.9 (SD 3.7), respectively. Significantly higher values for Mean Deviation (HEP-FDF: mean, -2.69, SD 2.59; HEP-SAP: mean, -0.52, SD 1.45; HFA-SAP: mean -0.64, SD 1.78; p<0.001) and Pattern Standard Deviation (HEP-FDF: mean 2.16, SD 1.13; HEP-SAP: mean, 1.53, SD, 0.91; p<0.001) were found in HEP-FDF tests.
Conclusions:
The FDF test is intended for early detection of glaucomatous visual fields. Tests using this instrument were associated with higher false negative values than HEP-SAP and HFA-SAP. However, patients performed better on the HEP-FDF in terms of fewer fixation losses and lower false positive rates. Additionally test duration was faster with the HEP-FDF. Higher MD values were found with HEP-FDF visual fields than both HEP-SAP and HFA-SAP strategies, but PSD more closely agreed with HFA-SAP when testing these patients with normal optic nerves.
Keywords: 642 perimetry •
758 visual fields