Purpose:
To explore the concordance between Standard Automated Perimetry (SAP) and Frequency Doubling Technology (Matrix) in identifying visual field deterioration in patients with glaucoma.
Methods:
Patients with glaucoma (n=64, median MD -4.0 dB, age 70 years, inter-quartile range (IQR) 63, 76 years) were followed with SAP (SITA-Standard 24-2 test) and FDT Matrix (24-2 threshold test). Examinations were performed in intervals of 6 month (median follow-up 5.0 yrs, 11 exams). Visual field data were analysed using "Permutation of Pointwise Linear Regression" (PoPLR), a technique that derives an overall p-value for localised visual field progression (O’Leary et al, ARVO 2012). Analyses were performed with total deviation (for focal as well as diffuse deterioration) and with pattern deviation (for focal deterioration only).
Results:
With total deviation, significant change (p<0.05) was detected in 39 eyes (61%) with either SAP and/or Matrix, and in 24 eyes (38%) with both techniques. With pattern deviation, significant change was identified in 34 eyes (53%) with either SAP and/or Matrix, but only 7 eyes (11%) were identified with both techniques (Fig). Similar trends were observed at a significance value of 1%.
Conclusions:
Both SAP and Matrix identified similar proportions of patients as having changed, but the concordance between SAP and Matrix appeared lower with pattern deviation than with total deviation. It is likely that SAP and Matrix perimetry identify different types of change.
Keywords: perimetry • visual fields • contrast sensitivity