TAKAHASHI, Hidenori, Tsuge, Taiki, Chiba, Mayumi, Esmaeelpour, Marieh, Kondo, Yusuke, Inoda, Satoru, Yamaguchi, Chingning Taffeta, Tanpo, Hironobu, Hashimoto, Yuto, Kimura, Kyouta, Kaburaki, Toshikatsu, Yanagi, Yasuo
EURETINA 2024 EURETINA
Purpose: To elucidate the subtypes and prognosis of dry Age-related Macular Degeneration (dry AMD) among Japanese patients defined as geographic atrophy size over 250 µm diameter. To calculate the incidence and progression rates of the various subtypes of dry AMD.
Setting/Venue: Forty consecutive cases of dry AMD patients attending Jichi Medical University were enrolled.
Methods: The patients had longitudinal data derived from Fundus Autofluorescence (FAF) imaging using a laser scanning ophthalmoscope over intervals exceeding three months. For bilateral cases, the eye with the larger area of atrophy fitting within the image frame was selected. Annotations for complete retinal pigment epithelium and outer retinal atrophy (cRORA) were performed using FAF by three independent annotators. The data were analyzed using Analysis of Variance (ANOVA) and t-tests.
Results: A total of 40 eyes with dry AMD (average age of 74 years (SD 8.2) and 50% males) had baseline complete retinal pigment epithelium and outer retinal atrophy (cRORA) area of 9.5 mm² (13), which increased to 15 mm² (18) at the final observation after an average follow-up of 2.3 years, progressing at a rate of 1.6 mm²/year (2.4). Subgroup analysis revealed:
Focal type was in 10 eyes and patients had an average age of 69 years, with males constituting 50% of this subgroup. The initial cRORA area was 4.9 mm², expanding to 6.5 mm² after an average of 1.6 years, with a progression rate of 0.25 mm²/year.
Banded type: 8 eyes, 78 years, 50%, 18 mm², 2 years, and 0.36 mm²/year.
Diffuse type: 10 eyes, 77 years, 30%, 7.1 mm², 2.9 years, and 3.7 mm²/year.
Diffuse trickling type: 4 eyes, 70 years, 50%, 7.3 mm², 1.3 years, and 3.0 mm²/year.
Patchy type: 4 eyes, 78 years, 100%, 2.9 mm2, 1.0 years, and 0.86 mm2/year.
There was no significant difference in age between groups. However, a significant difference was observed in the progression rate, with the diffuse type demonstrating a faster progression compared to the pachy, banded, and focal types (P < 0.05).
Conclusions: This study identified the FAF pattern classification in the Japanese population. Compared to Caucasian population reported by FAM-Study Group, there were fewer diffuse and more focal types.