Comparison of Microperimetry and Static Perimetry for Evaluating Macular Function and Disease Progression in Retinitis Pigmentosa

Abstract

Purpose : Macular function in retinitis pigmentosa (RP) is assessed by microperimetry (MP) and static perimetry such as Humphrey field analyzer (HFA); however, it is unclear which test is superior in evaluating macular status and progression. In this study, we compared the usefulness of MP-3 and HFA10-2 in RP patients, using macular anatomical metrics as a reference.

Methods : Forty-eight eyes of 48 RP patients in Kyusyu University Hospital who underwent MP-3 and HFA10-2 testing at least 3 times during ≧ 2-years were included. Macular anatomy (ellipsoid zone [EZ] length) was assessed by OCT. Macular function was assessed by MP-3 (mean retinal sensitivity at radii 2° , 4° and 8°) and HFA10-2 program (mean retinal sensitivity at radii 2° and 4°) and mean deviation (MD) values (radius 10°). Correlations between functional and anatomical parameters were analyzed cross-sectionally at baseline and longitudinally by comparing the rate of progression.

Results : The median age at baseline was 51.5 years [ICR: 43.8 to 59.3], with the median follow-up period of 2.96 years [2.08 to 3.27]. In cross-sectional analysis, EZ length was significantly correlated with MP-3 mean retinal sensitivity at radii 2°, 4° and 8° (Spearman’s ρ=0.65, 0.84, 0.89, all P < 0.01) and HFA10-2 mean retinal sensitivity at radii 2°, 4° and MD values (ρ=0.61, 0.73, 0.77, all P < 0.01). The longitudinal analysis showed that the slope of EZ length (-95.62 µm/year [-139.24 to -26.61] ) was significantly correlated with the slope of MP-3 retinal sensitivity at 8° radius (-0.57 dB/month [-0.87 to -0.29]; ρ=0.31, P =0.03) and the slope of HFA MD values at 10° radius (-0.51 dB/month [-1.10 to -0.15]; ρ=0.41, P =0.04).

Conclusions : Both MP-3 and HFA values correlated well with EZ length in the cross-sectional analysis of RP patients; however, these correlations became weaker in the evaluation of progression. In longitudinal analysis, the rate of retinal sensitivity loss at 8-10° radius was best associated with EZ length progression.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.