Abstract
Purpose:
To evaluate and compare visual field asymmetry score between non-glaucoma subjects with early stage of POAG patients using new method of inter-eye and intra eye asymmetry analysis in detecting early glaucomatous field loss.
Methods:
Ophthalmology records of 600 non-glaucomatous eyes of 300 subjects (having normal optic nerve head appearances and normal visual field test findings using Humphrey Field Analyzer II, 24-2 SITA testing procedures) and 400 eyes of 200 early stages of POAG patients (based on Stage 1 in GSS II classification) in Manchester Royal Eye Hospital were studied retrospectively. Intra-eye asymmetry score was obtained by calculating up-down difference in pattern deviation score in 22 mirror-imaged points (n=22 points at superior, n=22 at inferior) in each eye. For inter-eye asymmetry score, right - left difference in pattern deviation value in 44 points used in GHT sectors in 24-2 test pattern were calculated.
Results:
In non-glaucoma group, participants' mean age was 52.3±14.6 years (range, 8 to 85.8 y). In POAG group, participants' mean age was 71.8±12.8 years (range, 20 to 96 y). The intra-eye asymmetry value (up-down difference) (P<0.001) and the inter-eye asymmetry value (right-left difference) (P<0.003) were found to be significantly different in the non-glaucoma group and the POAG group.
Conclusions:
We suggest that these new quantitative inter-eye and intra-eye asymmetry analysis can help to differentiate a non-glaucoma patients from a patient with early glaucomatous field loss.
Keywords: 758 visual fields •
642 perimetry •
465 clinical (human) or epidemiologic studies: systems/equipment/techniques