Post Re-attachment Retinal Re-detachment

In this report, we consider retinal detachment in the eye, which happens when the retina comes away from the choroid. This condition is often treated by removing the vitreous humour from the eye (vitrectomy) and spot-welding the retina back on to the choroid. After this, the vitreous body is refilled with saline or silicone oil. The vitreous humour is a viscoelastic material, with a very high effective viscosity, and therefore it remains almost stationary relative to the position of the eyeball. However, after the vitrectomy, linear viscous fluid flows will occur in the vitreous body. One post-operative complication that may arise is re-detachment of the retina, which may occur due to increased wall shear stress in a post-vitrectomy eye, caused by the fluid flows. Two mechanisms have been postulated for these flows: • The front of the eye is exposed to the cold atmosphere, meaning that the front wall of the posterior chamber will be at a slightly lower temperature than the back wall. The cooler fluid will have a slightly higher density, so it tends to sink, which in turn drives a flow throughout the posterior chamber. University of Oxford University of Southampton University of Nottingham University of Strathclyde University of Glasgow Heriot-Watt University 1 Report on a problem studied at the UK Mathematics-in-Medicine Study Group Strathclyde 2004 < http://www.maths-in-medicine.org/uk/2004/retinal-detachment/ >