A 6-month-old boy with different colored eyes since birth. The parents are concerned that the eye anomaly may be associated with an underlying condition after reading about eye disorders online. They think the color of the eyes may have darkened slightly but have not noticed an unequal appearance to the pupils or drooping of either upper eyelid. No family members, including an older brother, have similar eye discoloration. There is no history of consanguinity. Otherwise healthy infant with normal stools and no chronic diarrhea. Prenatal and postnatal histories uneventful, developmental milestones appropriate. No history of prenatal maternal infections or perinatal trauma. Results of newborn hearing screen normal, no hearing problems subsequently reported.
Happy infant with stable vital signs. Physical findings and growth parameters essentially within normal limits for age. Ocular examination reveals normal lids and lashes, with no ptosis, bruising, or port-wine stains. Conjunctiva is white, with no corkscrew vessels. Cornea is clear; anterior chamber is deep and appears quiet. Right iris has dark brown pigmentation except for the area between the 6 and 8 o’clock position, which is bluegray and sharply demarcated. Iris architecture appears normal, although the iris crypts are less visible in the darker brown area of the right eye on close examination. Left iris is blue-gray at the periphery and hazelbrown centrally near the pupil. Remaining ocular findings normal. Extraocular movements intact in all directions. Both pupils dilate equally in the dark and constrict equally in response to light.
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