Neurobiology of the Eye
Modulation of choroidal thickness by diurnal rhythms, light and dopamine
Experiments in animal models of myopia have shown that the choroidal thickness is a powerful precursor of changes in axial eye growth- thick choroid means myopia and eye growth inhibition, thin choroid means eye growth stimulation and myopia development. It is known that bright light inhibits myopia, but the dose response curves and the effects on the choroid are not known.
Using small animal OCT (Heidelberg Engineering), the changes in choroidal thickness can be nicely tracked in alert chickens. They just need to be held in front of the OCT machine by hand and at the right position, and nice fundus images emerge (example, see picture: choroid).
Light has a distinct effect on choroidal thickness. Details will be reported at the 2013 ARVO meeting.
German Academic exchange service (DAAD) China-Mongolei.