[Electron microscopic study of the iris and bulbar conjunctiva of Werner's syndrome]

We observed the iris and the upper limbal conjunctiva from the two cases of Werner's syndrome by transmission electron microscopy. Numerous microfibrils were seen between the iris pigment epithelium and the dilator muscle, and within the stroma of the conjunctiva in both patients' eyes. These similar findings in the irides of both patients suggested the relationship between the microfibrils and Werner's syndrome. Many melanosome complexes were found in iris melanocytes, and the basement membrane of the iris vessels showed marked thickening. These findings seemed to be the changes caused by aging in cases of Werner's syndrome.