Molecular markers identified for pseudoexfoliation, a unique eye disease, that helps uncover its association with glaucoma


23 Mar 2018

Molecular markers identified for pseudoexfoliation, a unique eye disease, that helps uncover its association with glaucoma

 

By Dr. Aparna Rao, Intermediate Fellow

LV Prasad Eye Institute, Patia, Bhubaneswar, Odisha

The focus of my current research is on a unique eye disease, pseudoexfoliation (PXF), which is not only associated with “dandruff like” flaky deposits (see Figure below) in different parts of the eye, but it is also associated with systemic conditions involving the heart, brain liver and other organs. Surprisingly, the exact nature/ source of these deposits, reason for its vast phenotypic/clinical diversity and the mechanism by which this disease leads to glaucoma or blindness in some eyes is poorly understood.  Interestingly, the diverse clinical forms of this disease is very well known and understood since 100 years with several earlier studies reporting its frequent association with glaucoma and blindness which is much more than other types of glaucoma. 

Despite several studies attempting to investigate this entity, it is still unclear which eyes with the deposits would develop raised eye pressure (intraocular pressure, IOP) and glaucoma over time, in the same patient. The proportional risk for developing glaucoma in earlier forms of the disease and various diverse clinical forms of the disease is also not known. Such information would help identify “at risk” features or clinical phenotypes which may signify a risk for developing glaucoma onset even in early disease stages allowing timely intervention and closer follow up. 

Contrary to conventional understanding and literature, our recent study published in PLoS One, showed glaucoma with significant changes in IOP with or without optic nerve damage in 30-40% of earlier pigmentary form of the PXF and further found >50% incidence of glaucoma in those with combined phenotypic variants in the same eye. We have identified specific clinical forms of PXF associated with more incidence of glaucoma which mandates closer follow up of these eyes.  We are working further to typify each variant and stage with specific molecular signatures in different tissues of the eye before clinically manifest glaucoma which may help identify “at risk cases” and prevent avoidable blindness.  

Figure: Images show differences in clinical pattern of deposits in eyes with pseudoexfoliation which may result in glaucoma in some patients.

 

Reference:

Clinical spectrum of pseudoexfoliation syndrome—An electronic records audit. Aparna Rao , Debananda Padhy, Prity Sahay, Amiya Pradhan, Sarada Sarangi, Gopinath Das, Niranjan RajPLoS One. 2017 Oct 27.