Patients with beta (b)-thalassemia (b-TM: b-thalassemia major, b-TI: b-thalassemia
intermedia) have a variety of complications that may affect all organs, including the eye.
Ocular abnormalities include retinal pigment epithelial degeneration, angioid streaks,
venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision
abnormalities, and acute visual loss. Patients with b-thalassemia major are transfusion
dependent and require iron chelation therapy to survive. Retinal degeneration may result
from either retinal iron accumulation from transfusion-induced iron overload or retinal
toxicity induced by iron chelation therapy. Some who were never treated with iron
chelation therapy exhibited retinopathy, and others receiving iron chelation therapy had
chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals
with b-thalassemia major viewed in light of new findings on the mechanisms and
manifestations of retinal iron toxicity.