Other Ocular Abnormalities in Sickle Cell Hemoglobinopathies
Many patients with SS or SC disease exhibit segmentation of blood in the conjunctival blood vessels. Numerous comma-shaped thrombi dilate and occlude capillaries, most often in the inferior bulbar conjunctiva and fornix (referred to as the comma sign). Similarly, small vessels on the surface of the optic nerve head can exhibit intravascular occlusions, manifested as dark red spots (called the nerve head sign of sickling). Angioid streaks have been reported clinically in up to 6% of cases of SS disease and in persons with sickle cell trait (Hb AS). The pathogenetic basis of this association is uncertain.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.