II. Pathophysiology

  1. Medial Longitudinal Fasciculus (MLF) - normal function
    1. On lateral gaze, Cranial Nerve 6 abducts the ipsilateral eye
    2. To maintain Conjugate Gaze, a signal is passed via MLF to the contralateral eye's CN 3 to adduct (medially) in parallel
  2. With a MLF lesion, the adducting eye via CN 3 fails to adduct
    1. In response, the abducting eye (via CN 6) demonstrates Nystagmus
  3. Extraocular Movement is normal in other directions
    1. Primary gaze remains parallel
    2. Eye convergence on near vision remains intact

III. Causes

  1. Older adults (esp. unilateral involvement)
    1. Vascular disease affecting the vertebrobasilar circulation
  2. Young adults (esp. bilateral involvement)
    1. Multiple Sclerosis
  3. Children
    1. Pontine glioma (MRI)
    2. Vasculitis may also cause Internuclear Ophthalmoplegia in this age group

IV. References

  1. Berson (1990) Ophthalmology Study Guide, AAO, p. 116-7

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Ontology: Internuclear Ophthalmoplegia (C0152134)

Concepts Disease or Syndrome (T047)
MSH D015835
ICD9 378.86
ICD10 H51.2
SnomedCT 49823009
English INO - Internucl ophthalmopleg, Ophthalmoplegia, Internuclear, Internuclear Ophthalmoplegias, Ophthalmoplegias, Internuclear, Internucl ophthalmopleg, lhermitte's syndrome, internuclear ophthalmoplegia, Internuclear ophthalmoplegia, Ophthalmoplegia internuclearis, Lhermitte's syndrome, Bielschowsky-Lutz-Cogan syndrome, INO - Internuclear ophthalmoplegia, Internuclear ophthalmoplegia (disorder), internuclear; ophthalmoplegia, ophthalmoplegia; internuclear, Internuclear Ophthalmoplegia
Dutch internucleaire oftalmoplegie, internucleair; oftalmoplegie, oftalmoplegie; internucleair, Internucleaire oftalmoplegie, Oftalmoplegie, internucleaire
French Ophthalmoplégie internucléaire, Ophtalmoplégie internucléaire
German internukleaere Ophthalmoplegie, Internukleäre Ophthalmoplegie, Internukleaere Ophthalmoplegie
Portuguese Oftalmoplegia internuclear, Oftalmoplegia Internuclear
Spanish Oftalmoplejía internuclear, Oftalmoplejía Internuclear, oftalmoplejía internuclear (trastorno), oftalmoplejía internuclear, síndrome de Bielschowsky - Lutz - Cogan, síndrome de Lhermitte
Japanese 核間性麻痺, カクカンセイマヒ
Czech Internukleární oftalmoplegie, internukleární oftalmoplegie
Korean 핵간 안근마비
Hungarian Internuclearis ophtamoplegia
Norwegian Internukleær oftalmoplegi
Italian Oftalmoplegia internucleare