9C81.1

ICD-11 MMS 2026-01

Fourth nerve palsy

Index terms

  • Fourth nerve palsy
  • 4th nerve palsy
  • atrophy of fourth cranial nerve
Show allHide
  • atrophy of trochlear nerve
  • fourth cranial nerve paralysis
  • fourth cranial nerve paresis
  • isolated trochlear nerve palsy
  • superior oblique palsy
  • trochlear nerve palsy
  • trochlear nerve paralysis
  • trochlear nerve weakness
  • Congenital trochlear nerve palsy
  • Congenital superior oblique palsy
  • Acquired trochlear nerve palsy
  • Acute trochlear nerve palsy
  • Chronic trochlear nerve palsy
  • Chronic trochlear nerve palsy, spread of comitance
  • Neuritis of fourth cranial nerve
  • inflammation of trochlear nerve
  • neuritis of trochlear nerve

Inclusions

  • isolated trochlear nerve palsy

Exclusions from above levels

  • 8A00.10 – ophthalmoplegia progressive supranuclear
  • 9C83.5 – Internuclear ophthalmoplegia
  • 9D01.0 – Internal ophthalmoplegia
Show allHide
  • 01 – Certain infectious or parasitic diseases
  • 05 – Endocrine, nutritional or metabolic diseases
  • 18 – Complications of pregnancy, childbirth and the puerperium
  • 19 – Certain conditions originating in the perinatal period
  • 22 – Injury, poisoning or certain other consequences of external causes
  • 8A21.0 – Posterior cortical atrophy

Sibling codes

  • 9C81.0 – Third nerve palsy
  • 9C81.2 – Sixth nerve palsy
  • 9C81.3 – Total external ophthalmoplegia
  • 9C81.4 – Cavernous sinus syndromes
  • 9C81.Y – Palsy of other specified ocular motor nerve
  • 9C81.Z – Palsy of unspecified ocular motor nerve

Foundation entity

Fourth nerve palsy – http://id.who.int/icd/entity/120848300

Allowed postcoordination axes

Part of: 9C81: Ocular motor nerve palsies › 09: Diseases of the visual system