Abstract
Purpose:
To compare the detection of functional loss in early glaucoma using standard automated perimetry and flicker defined form perimetry.
Methods:
156 early-moderate glaucomatous subjects were recruited (average age: 62.6±11.0; 75 male, 78 OD). Humphrey Field Analyzer (HFA) SITAStd 24-2 classified subjects as 130 early glaucoma eyes and 26 moderate glaucoma eyes using a modified Hodapp criteria (MD: -2.12±2.04dB; PSD: 2.56±1.78dB). The Heidelberg Edge Perimetry (HEP) was used to perform both standard automated perimetry (HEP-SAP) and flicker defined form perimetry (HEP-FDF). Of note is that both forms of perimetry share the identical normative database. Participants were tested at 3 visits within a 3 month period, including HFA SITAStd 24-2 (visit 1), HEP-SAP ASTAStd 24-2 (visit 2&3) and HEP-FDF ASTAStd 24-2 (all visits). Unreliable visual fields were excluded from the study.
Results:
The HEP-FDF gave more defects (2514 PD less than 5%, 1568 less than 1%, 1357 less than 0.5%; MS:13.33±6.34 dB) than HEP-SAP (1817 PD less than 5%, 833 less than 1%, 647 less than 0.5%; MS: 27.89 ±3.91 dB). Test re-retest characteristics were similar for both HEP-FDF(r=0.82, MoD=-0.43, CoR=7.47) and HEP-SAP(r=0.75,MoD=-0.15, CoR=5.45) in our study. Test time was significantly (p<0.001) longer for HEP-FDF (463.12±150.97 sec) than HEP-SAP (353.19±75.84 sec), due to the larger number of field defects detected by HEP-FDF.
Conclusions:
Visual field defects were detected earlier by HEP-FDF when compared to HEP-SAP in early glaucoma. Both tests gave similar test-retest characteristics. There was a similar test time for similar amounts of defect. The greater the defect the longer the test time.
Keywords: 758 visual fields •
642 perimetry •
612 neuro-ophthalmology: diagnosis