Nerve compressed by aneurysm of posterior communicating aery is

Occulomotor nerve Most unruptured intracranial aneurysms are completely asymptomatic. Symptoms are usually due to rupture and resultant subarachnoid hemorrhage. Occasionally neurological symptoms may arise due to mass effect of the aneurysm. Progressively enlarging unruptured aneurysm most commonly involves the occulomotor nerve. This usually occurs .from an expanding aneurysm at junction of post communicating aery and internal carotid aery. Other neuropathies due to intracranial aneurysms are Cavernous sinus aneurysm can produce sixth nerve palsy. Supraclinoid carotid or anterior cerebral aery aneurysm can produce visual field defects. Posterior inferior cerebellar aery or anterior inferior cerebellar aery aneurysm may present as occipital & posterior cervical pain. An expanding middle cerebral aery aneurysm can produce pain in or behind the eye & in the low temple. Ophthalmic aery aneurysm can cause visual loss by compressing optic nerve.