J Korean Soc Magn Reson Med.  2014 Jun;18(2):167-170. 10.13104/jksmrm.2014.18.2.167.

Medial Longitudinal Fasciculus on MRI in a Patient with Internuclear Ophthalmoparesis: A Case Report

• Kim SM
• Kim HK
• Lee HJ

• KMID: 2099893
• DOI: http://doi.org/10.13104/jksmrm.2014.18.2.167

Abstract

The medial longitudinal fasciculus (MLF) is myelinated composite tract, lying near the midline, ventral to periaqueductal grey matter that plays a key role in coordinating eye movements. A lesion of the MLF results in an ipsilateral adduction deficit and a contralateral abducting nystagmus, referred to as an internuclear ophthalmoparesis. The blended tract with adjacent white matter in pons and midbrain is indistinguishable on brain imaging such as CT and MRI. Until now, to the best of our knowledge, MLF is not delineated on in vivo MRI. We present a case showing the whole connecting courses of MLF lesion on MRI in a patient with inflammatory demyelinating disorder.

Keyword

Medial longitudinal fasciculus; Internuclear ophthalmoparesis; Magnetic resonance imaging (MRI)

MeSH Terms

Deception
Demyelinating Diseases
Eye Movements
Humans
Magnetic Resonance Imaging*
Mesencephalon
Myelin Sheath
Neuroimaging
Ophthalmoplegia*
Pons

Figure

• 

  Fig. 1 T2 weighed image of MR imaging showed bilateral contiguous high signal intensities at the posterior aspect of pons and midbrain. High signal intensities of the pons represent ascending fibers from the abducent nucleus (a, arrow) to the occulomotor nucleus (d, arrow) via medial longitudinal fasciculus (b and c). The bilateral fasciculi run medially and decussated at the lower level of midbrain (c, arrows).

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