Features of retinal whitening:
(1) It is manifested as opacification with a color that ranges from subtle grey to white
(2) It tends to involve retinal vascular watershed areas.
(3) The center of the fovea is typically spared.
(4) Peripheral whitening spares the perivascular retina.
(5) Peripheral whitening may show a mosaic pattern.
Macular whitening is graded based on the cumulative size of involvement::
(1) mild: total area less than one third of a disc area
(2) moderate: total area from one third to 1 disc area
(3) severe: total area greater than 1 disc area
Peripheral (extra-macular) whitening is graded:
(1) mild
(2) moderate
(3) severe, with patches of confluence or widespread mosaic pattern
peripheral whitening score =
= SUM(grade for all quadrants examined) / (number of quadrants examined)
Interpretation:
• The peripheral whitening score ranges from 0 to 3.
