Figure 7.

Multimodal imaging of the left eye of a 68-year-old woman obtained over a 2-year period: (A–E) baseline visit, (F–J) 1-year follow-up visit, and (K–O) 2-year follow-up visit; (A, F, K) color fundus (CF) images, (B, G, L) near infrared (NIR) images, (C, H, M) fundus autofluorescence (FAF) images, (D, I, N) en face swept-source (SS) OCT images, and (E, J, O) drusen volume maps. A–E, Images obtained at the baseline visit displaying several calcified drusen on the CF (A), NIR (B), and en face SS OCT (D) images that are depicted by the yellow arrows. F–J, Images obtained at the 1-year visit displaying a hypertransmission defect (hyperTD) around the periphery of one of the hypotransmission defects (hypoTD) on the en face SS OCT image (I, blue arrow). This is known as a donut lesion, which is defined as hyperTDs surrounding a hypoTD core. This is the result of the en face SS OCT image being able to detect hyperTDs around the borders of the calcified drusen, but not above the lesion, because the calcified material within the drusen attenuates or scatters the incident light from the SS OCT instrument. In contrast, the FAF image (H) displays hypoautofluorescence in the entire area of the calcified drusen (blue arrow), which demonstrates that atrophy develops both on top and around the area of the calcified drusen. As a result, donut lesions on the en face SS OCT image represents calcified drusen that has progressed to atrophy. K–O, Images obtained at the 2-year visit showing more donut lesions that developed on the en face SS OCT image (N) that are depicted by the red arrows. In addition, the FAF image (M) displays hypoautofluorescence in the same area as the donut lesions (red arrows).