Duration 5min, Q&A 3min
Structure and Function in Multifocal Pupillographic Objective Perimetry (mfPOP)
To compare correlations between peripapillary retinal nerve fibre layer (RNFL) thicknesses and visual field changes detected using SAP and multifocal pupillographic objective perimetry (mfPOP) in glaucoma.
Structure-function correlations were computed for data from 25 open angle glaucoma patients and 25 normal control subjects.
All subject were tested using SAP thresholds and fields derived from three mfPOP stimulus protocols: 1) LumBal: luminance-balanced bright yellow stimuli on a 10 cd/m2 yellow background; 2) Lum+Col: 150 cd/m2 green stimuli on 10 cd/m2 red; and 3) Lum+ColBal = Lum+Col but with luminance balancing. Field data were grouped in arcuate clusters according to Stratus OCT sectors. Pearson correlation coefficients (r) by test region and arcuate cluster were calculated between mfPOP or SAP deviations and RNFL deviations from normative data.
Results and Conclusion
The strongest correlations were observed in the superior-superotemporal sector in severe glaucoma eyes: r=0.94 and r=0.90 for the mfPOP LumBal and Lum+Col protocols respectively (both n=16, p<0.05). Correlations across all test-points in both SAP and mfPOP were strongest in eyes with severe glaucoma (SAP MD<-12dB): SAP r=0.56, LumBal r=0.55, Lum+Col r=0.52, Lum+ColBal r=0.41 (all n=192, p<0.05). No significant correlation was observed in normal subjects for mfPOP or SAP. For all patient eyes taken together SAP correlations were higher than mfPOP, however scatterplots of mfPOP/RNFL deviations were quite linear while SAP data saturated. For both methods the largest correlations with RNFL thickness corresponded to the inferior nasal field of more severely damaged eyes. Head to head comparison of mfPOP and SAP showed similar structure/function relationships.
[ Keyword ]
perimetry / pupillography / structure/function / neuro-ophthalmology / glaucoma
[ Conflict of Interest ]
[ Conflict of Interest (Potential conflict) ]
We have received research support from Seeing Machines Ltd to develop the proto-type. Maddess, James and Carle hold patents and applications licenced to Seeing Machines. Maddess receives royalties from Carle Zeiss Meditec for sales of the FDT/Matrix perimeters.