A developmental disorder of the eye, Microphthalmia (or microphthalmos) means small eyes. Presentation In mammals the failure of expression of a transcription factor, MITF (microphthalmia-associated transcription factor), in the pigmented retina prevents this structure from fully differentiating. This in turn causes a malformation of the choroid fissure of the eye, resulting in the drainage of vitreous humor fluid. Without this fluid, the eye fails to enlarge, thus the name microphthalmia. Caus… (More on Microphthalmia)