Last reviewed: 3 Jul 2021
Last updated: 21 Jun 2018




  • Ischemic optic neuropathy (II)
  • Multiple sclerosis (II)
  • Viral infection (II)
  • Subarachnoid hemorrhage (III, IV, VI)
  • Meningitis (III, IV, VI)
  • Ischemic neuropathy (III, IV, VI)
  • Vascular malformations (V)
  • Herpes zoster (V)
  • Multiple sclerosis (V)
  • Bell palsy (VII)
  • Ramsay Hunt syndrome (VII)
  • Cerebrovascular accident (VII)
  • Vestibular neuritis (VIII)
  • Neural presbycusis (VIII)
  • Drugs (VIII)
  • Iatrogenic (X)
  • Apical lung tumor (IX, X)
  • Iatrogenic (XI)
  • Cerebrovascular accident (XII)


  • Trauma (I)
  • Neurodegenerative disorders (I)
  • Congenital (I)
  • CNS tumors (I)
  • Optic canal trauma (II)
  • CNS tumors (II)
  • Idiopathic intracranial hypertension (II)
  • Autoimmune disease: (e.g., SLE, Sjogren, granulomatosis with polyangiitis, Behcet [II])
  • Leber hereditary optic neuropathy (II)
  • Optical toxins or nutritional deficiency (II)
  • Neuromyelitis optica (II)
  • Uncal herniation (III, IV, VI)
  • Migraine (III, IV, VI)
  • Trauma (III, IV, VI)
  • Cerebral aneurysms (III, IV, VI)
  • Cavernous-carotid fistula (III, IV, VI)
  • Cavernous sinus thrombus (III, IV, VI)
  • CNS tumors (III, IV, VI)
  • Drugs (III, IV, VI)
  • Idiopathic intracranial hypertension (III, IV, VI)
  • Congenital (III, IV, VI)
  • Post-LP (VI)
  • Meningitis (V)
  • CNS tumors (V)
  • Autoimmune disorders (V)
  • Skull-base osteomyelitis (V)
  • Trauma (V)
  • Dental abscess (V)
  • Spinal cord lesion (V)
  • Iatrogenic (V)
  • Mandibular tumors (V)
  • Congenital (V)
  • Tolosa-Hunt syndrome (V)
  • Wallenberg syndrome (V)
  • Neurosarcoidosis (VII)
  • CNS tumors (VII)
  • Trauma (VII)
  • Meningitis (VII)
  • Iatrogenic (VII)
  • Middle ear or mastoid infection (VII)
  • Parotid tumor (VII)
  • HIV associated (VII)
  • Lyme disease (VII)
  • CNS tumors (VIII)
  • CNS tumors (IX, X)
  • Parapharyngeal tumor (IX, X)
  • Meningitis (IX, X)
  • Skull-base osteomyelitis (IX, X)
  • Trauma (IX, X)
  • Parapharyngeal space infection (IX, X)
  • Eagle syndrome (IX)
  • Cardiovocal syndrome (X)
  • Trauma (XI)
  • CNS tumors (XI)
  • CNS tumors (XII)
  • Progressive bulbar palsy (XII)
  • Chiari I and II malformations (XII)
  • Extracranial (tongue or neck) or skull-base tumors (XII)
  • Meningitis (XII)
  • Skull-base osteomyelitis (XII)
  • Parapharyngeal space infection (XII)
  • Trauma (XII)
  • Dural arteriovenous fistula (XII)
  • Internal carotid artery aneurysm or dissection (XII)
  • Iatrogenic (XII)



Ann Johnston, MB BS, MRCP

Consultant Neurologist

Department of Neurology

University Hospital of Wales




AJ declares that she has no conflicting interests.

Emma Tallantyre, BMBS, PhD

Neurology Specialist Registrar

University Hospital of Wales




ET declares that she has no conflicting interests.


Dr Johnston and Dr Tallantyre would like to gratefully acknowledge Dr Zachary L. Hickman, Dr Brad E. Zacharia, Dr Christopher J. Winfree, and Dr Adrian J. Wills, the previous contributors to this monograph. ZLH, BEZ, CJW, and AJW declare that they have no competing interests.

Peer reviewers

Robert L. Ruff, MD, PhD

Professor of Neurology

Department of Neurology

Cleveland VA Medical Center




RLR declares that he has no competing interests.

Sabrina Ravaglia, MD, PhD

Staff Physician

Department of Neurological Sciences

Institute of Neurology C. Mondino




SR declares that she has no competing interests.

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