Abstract
Abstract: :
Purpose: To investigate correlations of polarimetric RNFLT parameters obtained with customised (C) and fixed angle (F) corneal compensation with retinal sensitivity (MS) as measured with FDP and W/W threshold perimetry. Methods: One randomly selected eye of 24 consecutive COAG patients without significant cataract (age: 63.1 ± 12.5 year, MD: 5.51 ± 5.22 dB) and 17 healthy control subjects (age: 31.9 ± 11.1 year, MD: –0.39 ± 0.95 dB) was imaged both with C and F modes of the GDx–VCC device. The corresponding visual fields (Octopus G2 normal strategy and FDP 30° threshold test) were reliable and obtained within one week from polarimetry. Correlation was calculated between superior (S), inferior (I) and global GDx parameters and W/W and FDP parameters, and Bonferroni’s correction was used for the p–values. Results:FDP and W/W MS (S, I and global) correlated significantly (r: 0.79 to 0.84, p<0.001, for each correlation) for the total subject population and the glaucoma subgroup, but not for the controls. In C mode, for all subjects S average, I average, S maximum and normalized S and I areas correlated positively with both W/W–MS and FDP–MS of the opposite hemifield (r: 0.52 to 0.67, p<0.001 for each parameter), but I maximum correlated only with W/W MS (r=0.49, p=0.02). In F mode, only normalized I area correlated with the opposite hemifield MS (FDP and W/W) and normalized S area with inferior hemifield W/W–MS (r: 0.50 to 0.55, p<0.001 for each correlation) for all subjects. No correlation was found for either subgroup with either functional test. In C mode, for all subjects TSNIT average, TSNIT SD, maximum modulation and ellipse modulation correlated positively with both W/W–MS and FDP–MS, and negatively with W/W–MD and FDP–MD (r: 0.50 to 0.70, p<0.02 for each correlation), but not with W/W–CLV and FDP–PSD. No correlation was found for the subgroups separately. Un–logging the dB values did not reveal any correlation for either subgroup with either compensation mode. Conclusions:Correlation between polarimetric RNFLT and retinal sensitivity is better for customised than fixed compensation. Within the glaucoma subgroup, however, correlations were not found. W/W perimetry and FDP did not show a different correlation with RNFLT in the customised compensation mode in our study.
Keywords: imaging/image analysis: clinical • nerve fiber layer • perimetry