Korean J Ophthalmol.  2005 Dec;19(4):305-306. 10.3341/kjo.2005.19.4.305.

Normal Abduction in a Patient with Duplicated Abducens Nerve

• Kim JH
• Hwang JM

• KMID: 754445
• DOI: http://doi.org/10.3341/kjo.2005.19.4.305

Abstract

PURPOSE
To our knowledge, there has been no report of ophthalmologic findings related with a duplicated abducens nerve in the ophthalmic literature. This study reports such findings. METHODS: An ophthalmologic examination was performed in one patient with a duplicated abducens nerve, revealed with thin-sectioned magnetic resonance imaging (MRI) across the brainstem level. RESULTS: The MRI disclosed a duplicated left abducens nerve. The patient was orthotropic in five cardinal positions, and her ductions and versions were full. CONCLUSIONS: One patient with a duplicated abducens nerve showed orthotropia and normal ocular movement.

Keyword

Duplicated abducens nerve; Magnetic resonance imaging; Ocular movement

MeSH Terms

Magnetic Resonance Imaging
Humans
Female
Eye Movements/*physiology
Adult
Abducens Nerve Diseases/congenital/diagnosis
Abducens Nerve/*abnormalities

Figure

• 

  Fig. 1 (A) Ocular versions demonstrating normal eye movement in both eyes. (B-E) Four 0.7-mm-thick slice images obtained with a T2-weighted 3D fast field echo MRI sequence show a single right abducens nerve (arrows), and a duplicated left abducens nerve (double arrows) emerging from the pontomedullary junction and coursing in a superior oblique direction toward the clivus. Before entering the clivus, the left nerves appear to be fused.

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