Aging changes of the choroidal dye filling pattern in indocyanine green angiography of normal subjects.

Abstract

To study the aging changes in the choroid of healthy volunteers with indocyanine green (ICG) angiography. Video ICG angiography with adjunctive computer-assisted image analysis was performed on 35 eyes of 30 healthy volunteers (age range, 21-81 years; mean +/- standard deviation, 50.5 +/- 16.2 years) to observe the aging changes of the choroid. In patients in the second and third decades of life, the subfoveal choroidal arterioles fluoresced initially with subsequent rapid filling of the feeding arterioles and choriocapillaris. The watershed zone was clearly observed. In patients older than age 50, the choroidal vasculature filled more slowly. Eventually, the margin of the watershed zone became blurred. The quantitative analysis showed that the number of choroidal arterioles and the fluorescent intensity in the macular region were reduced with age (P < 0.005). In the early venous phase, hypofluorescent patches seen in all ages increased in size and number and remained with aging. The mean fluorescence intensity was not correlated statistically with age. The features of normal aging patterns of the choroid that we investigated are essential to the interpretation of ICG angiography and may help in understanding the physiologic and pathologic conditions of the choroidal circulations and the choroid and retina themselves.