A tumor exerting pressure on an optic nerve eventually causes optic atrophy. As it enlarges and finally causes elevation of intracranial pressure, papilledema occurs in the opposite eye, but not in the eye with the optic atrophy, for in this eye the sheath about the nerve is closed by the tumor at the optic foramen so that the cerebrospinal fluid pressure cannot be transmitted to the nerve head. The syndrome of ipsilateral optic atrophy and contralateral papilledema due to a basofrontal or subfrontal tumor is called Kennedy's syndrome or, perhaps more correctly, the Paton-Kennedy syndrome. The most comprehensive paper on the subject since the original one by Kennedy in 1911 is that of Jefferson (1945),1 who found 14 cases among 100 frontal lobe tumors and listed five variants of the syndrome.
In this paper are described a typical case of the Kennedy syndrome and also a variant not mentioned
LEVATIN P. Increased Intracranial Pressure Without Papilledema. AMA Arch Ophthalmol. 1957;58(5):683-688. doi:10.1001/archopht.1957.00940010703006