Posters

Electron microscopic evaluation of anterior lens epithelium and the basement membrane in patients with exfoliation syndrome

Poster Details

First Author: S.Kocabeyoglu TURKEY

Co Author(s):    O. Dikmetas   Y. Kapucu   M. Sargon              

Abstract Details

Purpose:

Exfoliation syndrome (XFS) is the most common identifiable cause of open-angle glaucoma in the world and is associated with an increased incidence of surgical complications in cataract surgery. The prevalence of XFS in Turkey, as recorded in epidemiological studies, is relatively high compared to other countries. Subsequent studies provided evidence for the systemic nature of XFS, which involves an aberrant connective tissue metabolism throughout the body. The aim of this study was to examine via electron microscopy the lens epithelial cells in age-related cataracts and compare the findings between patients with and without exfoliation syndrome, in the Turkish population.

Setting:

Hacettepe University Faculty of Medicine, Ankara, Turkey

Methods:

This is a prospective interventional study. The anterior lens capsules (basement membrane and lens epithelial cells) were taken from 10 eyes of 10 with and without exfoliation syndrome patients who were diagnosed as having age-related cataracts. All participants who were similar age, had no systemic diseases. The anterior lens capsules were obtained from cataract surgery and prepared for transmission electron microscopy (TEM). The ultrathin sections of the obtained tissue blocks were cut with an ultramicrotome (LKB Nova, Sweden). These ultra thin sections were stained with uranyl acetate and lead citrate and they were examined under Jeol JEM 1200 EX TEM.

Results:

Some significant ultrastructural changes were observed in all anterior lens capsules of the participants. Changes of the lens epithelial cells (LECs), which may be characterized as degenerative, were observed in all specimens. The LECs frequently were completely destroyed or absent, exhibiting loose connections amongst them or with the basement membrane and thickness of the epithelium was thinner than the control group. In the LECs there were many cells having pyknotic nuclei and many vacuoles inside the cytoplasm which are apoptotic. Diffuse intracellular or extracellular oedema were noticed to a varying degree and transparent vacuoles were detected. The cells were loosely connected with the basement membrane.

Conclusions:

Transmission electron microscope examination revealed ultrastructural abnormalities in all patients’ lens epithelia, more extended and more frequently observed in XFS group. There are few studies in which degeneration and transdifferentiation of cataractic lens epithelial cells were observed and discussed. Some alterations could be seen with different types of cataracts (intumescent, traumatic, atopic) included degenerative lesions, such as swelling, flattening, or loss of cells and nuclear pyknosis or swelling. Patients with these types of cataract were excluded from the present study. However, many aspects of the pathogenetic process of exfoliation syndrome still remain obscure, so further research is still required.

Financial Disclosure:

None