"Myopia (or near-sightedness) is a condition where the eye grows larger than normal. It is the fourth most common cause of blindness. There is currently no effective treatment to stop its development, and corrective lenses are used instead to compensate for the excessive eye length. Myopia is a common condition that affects more than one third of the European population, and is anticipated to increase in the future. This project aims to identify the mechanism for malignant eye growth. The retina is a tissue sheet in the eye responsible for photodetection, and Mueller cells are the only cells spanning the entire retinal thickness. During excessive eye growth a signal is transduced from the retina outwards to the hard shell of the eye, the sclera, but the nature of the signal is unknown. We propose that eye size is controlled by alteration of the retinal structure, allowing pressure to act on the underlying tissue as a signal. The contractile tone of Mueller cells can be pharmacologically altered in vitro, by substances implicated in myopia development. We believe that relaxation of Mueller cells either increase the retinal thickness thereby increasing the pressure, or increased retinal elasticity allow the intraocular pressure to act on the pigment epithelium as a signal for eye growth. To reveal the role of retinal and Mueller cell biomechanics in myopia, we will perform rheology measurements on retinae from guinea pig eyes with induced myopia. Comparisons with normal retinae will give a clear understanding if increased retinal elasticity is correlated with myopic development. We will investigate if the retina expands after exposure to drugs causing myopia, and by use of a custom-made device we will study if the retina transduce a mechanical force. To identify new pharmacological targets for intervention we will monitor retinal thickness or elasticity changes after interference with cytoskeletal components, such as microtubules, in Mueller cells."