The findings, published in a paper in the BritishJournal of
Ophthalmology, could shed new light on glaucoma, a devastating disease caused
bydefective drainage of fluid from the eye and the world's second leading cause
of blindness.
The latest research shows that the new layer, dubbed Dua's
Layer after the academic ProfessorHarminder Dua who discovered it, makes an
important contribution to the sieve-like meshwork, thetrabecular meshwork (TM),
in the periphery of the cornea.
The TM is a wedge-shaped bandof tissue that extends along
the circumference of the angle of the anterior chamber of the eye.It is made of
beams of collagen wrapped in a basement membrane to which trabecular cells
andendothelial cells attach. The beams branch out randomly to form a
'meshwork'.
Pressurewithin the eye is maintained by the balance of
aqueous fluid production by eye tissue called theciliary body and drainage
principally through the TM to the canal of Schlemm, a circular channelin the
angle of the eye.
Defective drainage through the TM is an important cause
ofglaucoma, a condition that leads to raised pressure in the eye that can
permanently affectsight. Around 1 to 2% of the world's population yearly have
chronic glaucoma and globally around45 million people have open angle glaucoma
which can permanently damage the optic nerve — 10% ofwhom are blind.
The latest research by Professor Dua and colleagues in
AcademicOphthalmology at The University of Nottingham sheds new light on the
basic anatomy of Dua'sLayer, which is just 15 microns thick but incredibly
tough. Comprised of thin plates ofcollagen, it sits at the back of the cornea
between the corneal stroma and Descemet'smembrane.
By examining human donor eyes using electron microscopy, the
researchers wereable to look at Dua's Layer beyond the central part of the
cornea to shed more light on itsfeatures at the extreme periphery of the
cornea. They discovered that the collagen fibres ofDua's Layer also branch out
to form a meshwork and that the core of TM is in fact an extensionof Dua's
Layer.
It is hoped the discovery will offer new clues on why the
drainage systemmalfunctions in the eyes of some people, leading to high
pressure.
Professor Dua said:"Many surgeons who perform lamellar
corneal transplant recognise this layer as an important
Source : medindia.net
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