Monocular temporal hemianopia with septo-optic dysplasia.

A 26-year-old woman displayed a monocular temporal hemianopic defect together with an ipsilateral afferent pupillary defect and bowtie optic nerve hypoplasia. MRI revealed a thin right optic nerve, an asymmetrically thinned chiasm, and an absent septum pellucidum. Monocular temporal visual field loss from organic lesions is quite rare but has been reported in conjunction with compressive lesions at the optic nerve-optic chiasm junction. This is the first report to demonstrate this visual field defect together with bowtie optic nerve hypoplasia.