Internuclear ophthalmoplegia
| Internuclear ophthalmoplegia | |
|---|---|
 | |
| Schematic demonstrating right internuclear ophthalmoplegia, caused by injury of the right medial longitudinal fasciculus. | |
| Specialty | Ophthalmology  |
Internuclear ophthalmoplegia (INO) is a disorder of
Causes
The disorder is caused by injury or dysfunction in the medial longitudinal fasciculus (MLF), a heavily myelinated tract that allows conjugate eye movement by connecting the paramedian pontine reticular formation (PPRF)-abducens nucleus complex of the contralateral side to the oculomotor nucleus of the ipsilateral side.
In young patients with bilateral INO, multiple sclerosis is often the cause. In older patients with one-sided lesions a stroke is a distinct possibility. Other causes are possible.[2]
Variants
A rostral lesion within the midbrain may affect the convergence center thus causing bilateral divergence of the eyes which is known as the WEBINO syndrome (Wall Eyed Bilateral INO)[3] as each eye looks at the opposite "wall".
If the lesion affects the
Diagnosis
Can be seen in multiple sclerosis, stroke, and other pathologies.[4] Accompanying symptoms include scanning speech, intention tremor, incontinence, and nystagmus.[5]
See also
References
- ^ "Internuclear Ophtalmoplegia".
- PMID 15883257.
- PMID 2094199.
- ^ Gold, Daniel R. "D.O." Neuro-Ophthalmology Virtual Education Library. Spencer S. Eccles Health Sciences Library, University of Utah. Retrieved 30 September 2019.
- ^ "Internuclear Ophthalmoplegia". The Lecturio Medical Concept Library. Retrieved 7 July 2021.
External links