Nipple atrophy on one side and edema on the other

It is more common in tumors or abscesses at the base of the frontal lobe, such as internal carotid aneurysms, olfactory sulcus meningiomas, anterior cranial concave meningiomas, and craniopharyngiomas. Others such as fusiform dilatation of the internal carotid artery, sclerosis of the internal carotid artery, trauma to the anterior cranial recess, and arachnoid anterior cranial arachnoiditis can also cause atrophy of the optic papilla on one side and edema on the other side. Because one side of the optic nerve was directly compressed by the tumor and atrophied, the intracranial pressure increased due to the continued growth of the tumor, resulting in edema in the healthy side optic papilla.