Fundus autofluorescence in premature infants

Abstract

To describe fundus autofluorescence (FAF) patterns in premature infants and to determine whether FAF increases gradually with increasing post-gestational age. This was a cross-sectional, observational and descriptive case series. FAF images were obtained from patients screened for Retinopathy of Prematurity. The presence of the following hypo-autofluorescence areas/structures was graded and ranked: macular pigment (foveal centre), optic nerve head, peripapillary vessels/vascular arcade (PP/VA), and equatorial vessels (EqV). Ranks were attributed to the number of structures visualized from the posterior pole towards the periphery. The rank of FAF could then be analysed by Spearman’s correlation against age. Additionally, patients were divided by age into group 1 (< 40 weeks of corrected gestational age (WCGA)) and group 2 (> 40 WCGA). Differences between groups were tested with the Mann–Whitney U test. Thirteen patients were analysed. The mean WCGA at examination was 47.85 weeks. Spearman’s correlation showed a strong positive correlation (r = 0.714) (P = 0.006) of FAF and WCGA. The Mann–Whitney U test revealed that the PP/VA and EqV were significantly more visible at > 40 WCGA than at < 40 WCGA (8.0 [P = 0.016] and 7.5 [P = 0.03], respectively). Patterns of FAF are described for the first time in premature infants. FAF increases gradually with age and centrifugally from the posterior pole towards the equator in premature infants.

Lipofuscin, Its Origin, Properties, and Contribution to Retinal Fluorescence as a Potential Biomarker of Oxidative Damage to the Retina

“…The emission intensity significantly increased in the elderly group in comparison with the younger group by 51% in the central fovea (a circle centred in the fovea with a 0.6 mm radius), by 45% in the areas of parafovea, perifovea, and perimacula (0.601-3 mm from the foveal centre), and by and 56% in the periphery (more than 3 mm from the centre of the fovea), respectively. This difference between the two groups is similar to that in measurements in vivo by Delori et al using similar excitation and emission wavelengths in age groups of about 55 and 80 years of age where the intensity of fluorescence in the eldest group is about 60% greater than in the 55-yearold group [335].…”

“…Consistent findings were reported by Delori and colleagues from a study on 145 participants ranging in age from 15 to 80 years where the fundus fluorescence was excited by 470 nm and the emission integrated above 520 nm [335]. The emission intensities reached a maximum for the age group in their 7 th decade and remained at the same level in the 8th decade.…”

“…In addition to the previously discussed studies by Feeney-Burns, Delori and colleagues [75,278], a number of other studies in vivo and ex vivo demonstrated an age-related increase in the fluorescence of the fundus and RPE-Bruch's membrane complex [147,148,284,335,336] (Table 1). Wing et al used 44 human eyes from 35 donors, ranging in age from a 6-week premature newborn to 88 years, and measured fluorescence from retinal cross-sections through the entire retina including the fovea and optic disc [147].…”

“…Emission in the blue range 460-480 nm shows an age-related increase even in the age range of 60 to 88 years [147]. At least three studies demonstrated that the emission collected >520 nm reaches a plateau above the age of 60 years [284,335,337]. Fluorescence emission excited by 550 nm light and collected in the red range of 650-750 nm exhibits an-age related increase up to the age of 70 years followed by a steep decrease [335].…”

“…Altogether, there is an age-related increase in fundus fluorescence intensity at least to the age of 60 years and is most pronounced in people of White ethnicity [284,335,337,338] (Table 1). Emission in the blue range 460-480 nm shows an age-related increase even in the age range of 60 to 88 years [147].…”