Conjunctival Rhinosporidiosis. Light and electron microscopic study.

Two cases of conjunctival rhinosporidiosis were studied by light and electron microscopy. Two distinct phases of the tissue life cycle were present: trophic and endosporulating. Young trophocytes contained a single nucleus. As the trophocyte matured chromatin was dispersed throughout the cyst. During the next phase of the life cycle, sporangial cyst walls acquired a new inner layer that appeared to give rise to endospores. Histochemical and ultrastructural features of Rhinosporidium seeberi are consistent with it being a fungus. Complete surgical excision of the lesion is the only known method to eradicate the infection.