Histology and immunohistochemistry of fibrous posterior capsule opacification in an infant.

We report the histological findings in posterior capsule opacification (PCO) in 2 eyes of a 10-month-old infant 8 months after cataract extraction and intraocular lens (IOL) implantation. The PCO in the right eye had a regenerated lenticular structure; in the left eye, it was fibrotic. The PCO in the right eye was soft and aspirated with Simcoe's irrigation/aspiration cannula; in the left eye, it was excised surgically. Paraffin sections of the fibrous PCO tissue from the left eye were examined histologically. Hematoxylin-eosin staining showed extracellular matrix (ECM) accumulation and the presence of elongated fibroblastic cells, presumed to be lens epithelial cells (LECs). Immunohistochemistry revealed the presence of fibrous collagen types and cellular fibronectin. The presumed LECs amid the ECM were positive for vimentin and alpha-smooth muscle actin. Histology of the fibrous PCO tissue from this infant was similar to that in adult patients.