Values for Macular Perimetry Using the MP-1 Microperimeter in Normal Subjects

PURPOSE: To establish values for the fixation pattern and macular sensitivity to light in healthy subjects using the MP-1 microperimeter (Nideck Technologies, Vigonza, Italy). METHOD: A prospective study of 37 healthy subjects (age: 19-71 years), approved by the institutional review board. Full-threshold microperimetry of the central 12 degrees of the retina (the macula) was performed prospectively, utilizing 16 points with the MP-1. The fixation stability was simultaneously recorded during microperimetry testing. The relationship between the fixation pattern and light sensitivity with age was calculated using linear regression analysis. RESULTS: Microperimetry was performed on 66 eyes. Total mean sensitivity was 18.33 dB (range: 13.0-19 dB). Mean macular sensitivities at 2 degrees , 4 degrees and 6 degrees as measured by the MP-1 were 18.4+/-2.0, 18.2+/-2.3 and 18.2+/-2.1 dB, respectively. The linear regression analysis revealed a 0.019240, 0.0248 and 0.0285 dB per year age-related decline in mean macular sensitivity at 2 degrees, 4 degrees and 6 degrees from the center of the macula, respectively. The total mean fixation stability values within 2 degrees and 4 degrees were 86 and 96%, respectively. The linear regression analysis also revealed a 0.344% and 0.122% per year decline in age-related fixation stability within 2 degrees and 4 degrees , respectively. There were no statistically significant differences between the median retinal sensitivity or fixation stability values for sex or race in the study. CONCLUSIONS: The MP-1 may be a reliable tool to measure macular sensitivity. Among normal healthy subjects, there was a linear decline in light sensitivity with increasing age.