Prolonged ocular hypotension: would ciliary tissue transplantation help

Aims Ocular hypotony and phthisis bulbi from persistent fistulae, ciliochoridal detachments, or inflammation, that cannot be treated currently. However, complete shutdown of the ciliary epithelium is rare. Secreting, transplanted ciliary tissue could restore the IOP to a level where further visual damage would not occur or even be reversed. Methods Allografts of ciliary epithelium and its substrate were placed on to the surface of the iris of normal albino rabbits. The progress of the transplanted tissue was followed in the untreated animals, those who had been immunosuppressed and those who had been immunosuppresed together with cold whole body perfusion for up to 55 days. Changes were assessed by slit-lamp observation, luconyl blue staining, fluoresceine angiography, and these were compared with the histology and electron microscopic appearances. Results Transplants survived the period of ischaemia in the anterior chamber. They started to be revascularised within 4 days and were completely revascularised in 12 days. Untreated animals showed classical rejection phenomena. However, the ciliary epithelial tissue in those animals who were immunosuppressed and had been subjected to whole body perfusion remained normal and were secreting aqueous, as judged by the histological and electron microscopic appearances. Conclusions Perfused allografts of ciliary tissue will survive in the normal anterior chamber of the immunosuppressed rabbit, and the electron microscopic evidence indicates that the tissue is producing aqueous. If this can be shown to be adequate in the damaged eye, then ciliary transplantation could be a valuable tool in the management of severe intractable hypotony.