The TM is a wedge-shaped band of 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 and endothelial cells attach. The beams branch out randomly to form a ‘meshwork’.
Optic nerve damage
Pressure within the eye is maintained by the balance of aqueous fluid production by eye tissue called the ciliary body and drainage principally through the TM to the canal of Schlemm, a circular channel in the angle of the eye.
Defective drainage through the TM is an important cause of glaucoma, a condition that leads to raised pressure in the eye that can permanently affect sight. Around 1 to 2% of the world’s population yearly have chronic glaucoma and globally around 45 million people have open angle glaucoma which can permanently damage the optic nerve — 10% of whom are blind.
The latest research by Professor Dua and colleagues in Academic Ophthalmology at The University of Nottingham sheds new light on the basic anatomy of Dua’s Layer, which is just 15 microns thick but incredibly tough. Comprised of thin plates of collagen, it sits at the back of the cornea between the corneal stroma and Descemet’s membrane.
By examining human donor eyes using electron microscopy, the researchers were able to look at Dua’s Layer beyond the central part of the cornea to shed more light on its features at the extreme periphery of the cornea. They discovered that the collagen fibres of Dua’s Layer also branch out to form a meshwork and that the core of TM is in fact an extension of Dua’s Layer.
It is hoped the discovery will offer new clues on why the drainage system malfunctions 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 part of the surgical anatomy of the cornea. This new finding resulting from a study of the microanatomy of the periphery of the layer could have significance beyond corneal surgery.”
The breakthrough discovery of Dua’s Layer was first revealed in a paper in the academic journal Ophthalmology in June last year and was widely covered by the world’s scientific and lay media.
The paper became the number one downloaded ophthalmology paper from the website ScienceDirect between July and September 2013 and was ranked the 11thmost downloaded from the website for the whole of medicine and dentistry.
The latest research paper, The Collagen Matrix of the Human Trabecular Meshwork is an Extension of the Novel Pre-Descemet’s layer (Dua’s layer), can be viewed online (after the embargo lifts) at http://dx.doi.org/10.1136/bjophthalmol-2013-304593
— Ends —
For up to the minute media alerts, follow us on Twitter
Notes to editors: The University of Nottingham has 42,000 students and is ‘the nearest Britain has to a truly global university, with campuses in China and Malaysia modelled on a headquarters that is among the most attractive in Britain’ (Times Good University Guide 2014). It is also the most popular university in the UK among graduate employers, one of the world’s greenest universities, and winner of the Times Higher Education Award for ‘Outstanding Contribution to Sustainable Development’. It is ranked in the World’s Top 75 universities by the QS World University Rankings.
More than 90 per cent of research at The University of Nottingham is of international quality, according to the most recent Research Assessment Exercise. The University aims to be recognised around the world for its signature contributions, especially in global food security, energy & sustainability, and health. The University won a Queen’s Anniversary Prize for Higher and Further Education for its research into global food security.
More information is available from Professor Harminder Dua on +44 (0)115 849 3354, 07866 317 975, [email protected]
Emma Thorne – Media Relations Manager
Email: [email protected] Phone: +44 (0)115 951 5793 Location: University Park