What causes a blue appearance of the white part of the eye?

Blue discoloration of the white part of the eye may involve several factors. 1. This condition could be due to congenital developmental abnormalities, which are more commonly seen in infants, young children, and women. It typically occurs when the sclera (the white outer layer of the eye) is relatively thin, allowing the underlying choroidal blood vessels to show through, resulting in a bluish appearance. 2. Iron deficiency anemia may also cause the whites of the eyes to appear blue. Iron deficiency can impair collagen fiber synthesis in the sclera, leading to progressive thinning and a subsequent bluish hue. 3. Other possible causes include genetic factors, incomplete ocular development, hyperbilirubinemia, and glaucoma. Genetic predisposition may lead to inheritance of this trait within families, while incomplete eye development might result in uneven thickness or density of the sclera, causing certain areas to appear blue. Pathological conditions such as hyperbilirubinemia and glaucoma may also contribute to abnormal coloration of the sclera.