On the presence of bilirubin in the ocular humors of premature infants.

The yellow pigments observed in the ocular humors of premature infants were identified as the plasma pigments bilirubin and oxyhemoglobin. The blood/vitreous humor barrier to bilirubin was estimated to be (1/0.11) for total bilirubin and (1/0.25) for direct-acting bilirubin. Hall method histochemical staining for bilirubin in sections of premature infant eyes was highly positive for the vitreous humor, and suggestive of uptake of bilirubin by the neural-retinal cells.