Pontine lesions can affect CNs V, VI, VII, and/or VIII. Ischemic and hemorrhagic infarcts are the most frequent cause of acute brainstem syndromes with the pons most frequently affected [1,132]. Nonischemic lesions affecting Cranial Neuropathy the brainstem include trauma, demyelinating disease, encephalitis, neoplasms, central pontine myelinolysis, neurodegenerative disorders, and syringobulbia [18,131,132]. Pontine syndromes causing variable involvement of CNs V-VIII, along with other neurologic deficits, include Millard-Gubler syndrome, Foville syndrome, locked-in syndrome, and facial colliculus syndrome [131]. The internal carotid artery with its surrounding sympathetic plexus and the abducens nerve extend through the center of the cavernous sinus, and the oculomotor, trochlear, and trigeminal nerves (1st and 2nd division) extend along the lateral wall of the cavernous sinus. Cavernous sinus lesions can result in isolated or multiple cranial neuropathies including involvement of the abducens and trigeminal nerves. Tumors, vascular lesions, infection, and inflammatory disorders can lead to cavernous sinus syndrome [18]. The cerebellopontine angle spans a craniocaudal extent that encompasses the cisternal portions of CNs V-X and is most frequently affected by benign tumors. Sensorineural hearing loss and tinnitus are the most common symptoms but can be accompanied by neuropathies of CNs V, VI, VII, IX, and X with larger tumors [18]. The combination of ipsilateral CN V and CN VII palsies raises concern for perineural spread of tumor, which is discussed in Variant 10. Additionally, leptomeningeal processes can lead to variable patterns of cranial neuropathy [18,132]. CT Maxillofacial There is no relevant literature to support the use of maxillofacial CT in the initial evaluation of multiple middle CN palsies.
Cranial Neuropathy. Pontine lesions can affect CNs V, VI, VII, and/or VIII. Ischemic and hemorrhagic infarcts are the most frequent cause of acute brainstem syndromes with the pons most frequently affected [1,132]. Nonischemic lesions affecting Cranial Neuropathy the brainstem include trauma, demyelinating disease, encephalitis, neoplasms, central pontine myelinolysis, neurodegenerative disorders, and syringobulbia [18,131,132]. Pontine syndromes causing variable involvement of CNs V-VIII, along with other neurologic deficits, include Millard-Gubler syndrome, Foville syndrome, locked-in syndrome, and facial colliculus syndrome [131]. The internal carotid artery with its surrounding sympathetic plexus and the abducens nerve extend through the center of the cavernous sinus, and the oculomotor, trochlear, and trigeminal nerves (1st and 2nd division) extend along the lateral wall of the cavernous sinus. Cavernous sinus lesions can result in isolated or multiple cranial neuropathies including involvement of the abducens and trigeminal nerves. Tumors, vascular lesions, infection, and inflammatory disorders can lead to cavernous sinus syndrome [18]. The cerebellopontine angle spans a craniocaudal extent that encompasses the cisternal portions of CNs V-X and is most frequently affected by benign tumors. Sensorineural hearing loss and tinnitus are the most common symptoms but can be accompanied by neuropathies of CNs V, VI, VII, IX, and X with larger tumors [18]. The combination of ipsilateral CN V and CN VII palsies raises concern for perineural spread of tumor, which is discussed in Variant 10. Additionally, leptomeningeal processes can lead to variable patterns of cranial neuropathy [18,132]. CT Maxillofacial There is no relevant literature to support the use of maxillofacial CT in the initial evaluation of multiple middle CN palsies.