Purpose: To investigate the macular sensitivity of healthy eyes of a wide age range as determined by macular Integrity Assessment (MAIA), and to investigate factors affecting macular sensitivity.
Subjects and methods: A total of 120 eyes of 120 healthy volunteers with a best-corrected visual acuity of 20/20 or better, and of a mean age of 43.1 years. Macular sensitivity was examined by a standard grid, a 37-stimuli grid covering the central 10° of the retina including one centering point.
Results: The central sensitivity (CS) was 28.9 dB for subjects under 20 years, 27.2 dB for subjects between 20 to 60 years, and 24.5 dB for subjects over 60 years. The average sensitivity (AS) was 29.6 dB for subjects under 20 years, and after that the sensitivity was 28.7 dB and 26.3 dB. Both CS and AS in subjects over 60 years exhibited a significantly lower sensitivity than in subjects under the age of 20 (p=0.01). Regression analysis results indicated that the sensitivity gradually decreased by approximately 0.6 dB every 10 years (p=0.01). The age and development of axial length were statistically significant factors influencing the decline in sensitivity (p=0.01). When each stimulus position was investigated, the center (0°) was significantly lower (26.4 dB) than surrounding stimulus positions (1°: 28.9 dB, 3°: 28.7 dB, 5°: 27.8 dB)(p=0.01).
Conclusion: The macular sensitivity in healthy Japanese subjects calculated by MAIA exhibited a significantly low value with aging, and sensitivity decreased with the advance in the development of axial length. The sensitivity of surrounding stimulus positions was higher than in the center (0°).
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 118: 15-21, 2014.