Abducting Nystagmus in the Medial Longitudinal Fasciculus (MLF) Syndrome (Internuclear Ophthalmoplegia [INO])1

2015 ◽  
pp. 367-376 ◽  
Author(s):  
M. H. Stroud ◽  
Nancy M. Newman ◽  
J. L. Keltner ◽  
A. J. Gay
Keyword(s):  
Medial Longitudinal Fasciculus ◽  
Internuclear Ophthalmoplegia

Lidocaine-induced unilateral internuclear ophthalmoplegia: effects on convergence and conjugate eye movements

1989 ◽  
Vol 62 (1) ◽  
pp. 82-95 ◽  
Author(s):  
P. D. Gamlin ◽  
J. W. Gnadt ◽  
L. E. Mays
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Open Loop ◽  
Medial Longitudinal Fasciculus ◽  
Slow Phase ◽  
Internuclear Ophthalmoplegia ◽  
Unaffected Side ◽  
Affected Side ◽  
Position Signal ◽  
Slow Drift

1. To characterize the vergence signal carried by the medial longitudinal fasciculus (MLF), it was subjected to reversible blockade by small injections of 10% lidocaine hydrochloride. The effects of these blockades on both conjugate and vergence eye movements were studied. 2. With this procedure, experimentally induced internuclear ophthalmoplegia (INO) and its effects on conjugate eye movements could be studied acutely, without possible contamination from long-term oculomotor adaptation. In the eye contralateral to the MLF blockade, saccadic and horizontal smooth-pursuit eye movements were normal. Horizontal abducting nystagmus, often seen in patients with INO, was not observed in this eye. 3. As previously reported for INO, profound oculomotor deficits were seen in the eye ipsilateral to the MLF blockade. During maximal blockade, adducting saccades and horizontal smooth-pursuit movements in this eye did not cross the midline. Adducting saccades were reduced in amplitude and peak velocity and showed significantly increased durations. Abducting saccades, which were slightly hypometric, displayed a marked postsaccadic centripetal drift. 4. The eye ipsilateral to the blockade displayed a pronounced, upward, slow drift, whereas the eye contralateral to the blockade showed virtually no drift. Furthermore, although vertical saccades to visual targets remained essentially conjugate, the size of the resetting quick phases in each eye was related to the amplitude of the slow phase movement in that eye. Thus the eye on the affected side displayed large quick phases, whereas the eye on the unaffected side showed only slight movements. On occasion, unilateral downbeating nystagmus was seen. This strongly suggests that the vertical saccade generators for the two eyes can act independently. 5. The effect of MLF blockade on the vergence gain of the eye on the affected side was investigated. As a measure of open-loop vergence gain, the relationship of accommodative convergence to accommodation (AC/A) was measured before, during, and after reversible lidocaine block of the MLF. After taking conjugate deficits into account, the net vergence signal to the eye ipsilateral to the injection was found to increase significantly during the reversible blockade. 6. The most parsimonious explanation for this increased vergence signal is suggested by the accompanying single-unit study. This study showed that abducens internuclear neurons, whose axons course in the MLF, provide medial rectus motoneurons with an appropriate horizontal conjugate eye position signal but an inappropriate vergence signal. Ordinarily, this incorrect vergence signal is overcome by another, more potent, v

scholarly journals Wall-eyed bilateral internuclear ophthalmoplegia (webino syndrome) and myelopathy in pyoderma gangrenosum

1990 ◽  
Vol 48 (4) ◽  
pp. 497-501 ◽  
Author(s):  
Marco Aurélio Lana ◽  
Paulo Roberto R. Moreira ◽  
Leonardo B. Neves
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Pyoderma Gangrenosum ◽  
Medial Longitudinal Fasciculus ◽  
Sensory Level ◽  
Internuclear Ophthalmoplegia ◽  
Central Nervous System Vasculitis ◽  
Exact Location ◽  
Vascular Occlusive Disease ◽  
Ocular Convergence

A 35-year-old female with pyoderma gangrenosum developed paraparesis with a sensory level at L1. Three months later she complained of diplopia and was found to have bilateral internuclear ophthalmoplegia with exotropia and no ocular convergence. The term Webino syndrome has been coined to design this set of neuro-opthalmologic findings. Although it was initially attributed to lesions affecting the medial longitudinal fasciculus and the medial rectus subnuclei of the oculomotor complex in the midbrain the exact location of the lesion is still disputed. In the present case both myelopathy and Webino syndrome were probably due to vascular occlusive disease resulting from central nervous system vasculitis occurring in concomitance to pyoderma gangrenosum.

Excitatory termination of abducens internuclear neurons on medial rectus motoneurons: relationship to syndrome of internuclear ophthalmoplegia

1978 ◽  
Vol 41 (6) ◽  
pp. 1647-1661 ◽  
Author(s):  
S. M. Highstein ◽  
R. Baker
Keyword(s):  
Brain Stem ◽  
Nerve Stimulation ◽  
Physiological Activity ◽  
Vestibular Nerve ◽  
Medial Rectus ◽  
Medial Longitudinal Fasciculus ◽  
Internuclear Ophthalmoplegia ◽  
Field Potentials ◽  
Abducens Nucleus ◽  
Stimulation Of

1. Field potentials and intracellular records were obtained from the medial rectus subdivision of the IIIrd nucleus in anesthetized cats following electrical stimulation of the abducens nuclei, vestibular nerves, pontomedullary brain stem, and the medial longitudinal fasciculi (MLF). 2. Stimulation of the contralateral abducens nucleus produced unique field potentials in the medial rectus subdivision. They consisted of an early sharp transient volley followed by a slower postsynaptic negativity. 3. Monosynaptic EPSPs were evoked in medial rectus motoneurons following contralateral abducens nucleus stimulation. The EPSP amplitudes were graded when the stimulus intensity was increased from threshold to supramaximal. EPSPs produced by contralateral abducens nucleus stimulation were larger in amplitude than those produced by ipsilateral vestibular nerve stimulation. The current-voltage relationship and reversal potentials for Vi- and abducens-evoked EPSPs were similar and indicated an overlapping location of excitatory synaptic terminals on medial rectus motoneurons. 4. Secondary vestibular axons activated monosynaptically by ipsilateral vestibular nerve stimulation were not recruited by abducens nucleus stimulation. 5. Ipsilateral MLF stimulation produced EPSPs with similar profiles as those observed following abducens nucleus stimulation; however, stimulation of the contralateral MLF at comparable stimulus intensities did not produce any changes in transmembrane potential. 6. When higher intensity stimuli were applied to the contralateral MLF, the synaptic potentials recorded in the medial rectus were occluded by those produced by weaker stimulation applied to the ipsilateral MLF. This suggests that the potentials resulting from stronger contralateral stimulation were due to current spread to the ipsilateral MLF. 7. While recording in the medial rectus subdivision, various sites in the ponto-medullary brain stem were explored with a stimulating electrode. Analysis of evoked field potentials suggested that the ascending internuclear axons were contained only in the MLF ipsilateral to the medial rectus. Acute brain stem lesions confirmed this suggestion. 8. Chronic lesions were placed in the brain stem to isolate the abducens nucleus from either extrinsic fibers of passage or axon collaterals. Acute electrophysiological experiments in these chronic animals corroborated the suggestion that the medial rectus pathway originated from within the abducens nucleus. 9. We conclude that axons from the internuclear neurons of the abducens nucleus exit from the nucleus medially, cross the midline, ascend in the opposite MLF, and terminate monosynaptically on medial rectus motoneurons. 10. we believe that the syndrome of internuclear ophthalmoplegia associated clinically with lesions of the medial longitudinal fasciculus could be due to the absence of ascending physiological activity from internuclear neurons of the abducens nucleus.

Impaired vestibular responses in internuclear ophthalmoplegia

Neurology ◽  
2017 ◽  
Vol 89 (24) ◽  
pp. 2476-2480 ◽  
Author(s):  
Seo-Young Choi ◽  
Hyo-Jung Kim ◽  
Ji-Soo Kim
Keyword(s):  
Vestibular Evoked Myogenic Potentials ◽  
Medial Longitudinal Fasciculus ◽  
Subjective Visual Vertical ◽  
Internuclear Ophthalmoplegia ◽  
Horizontal Canal ◽  
Head Impulse ◽  
Ocular Tilt Reaction ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Visual Vertical

Objective:To determine the role of the medial longitudinal fasciculus (MLF) in conveying vestibular signals.Methods:In 10 patients with isolated acute unilateral internuclear ophthalmoplegia (INO) due to an acute stroke, we performed comprehensive vestibular evaluation using video-oculography, head impulse tests with a magnetic search coil technique, bithermal caloric tests, tests for the ocular tilt reaction, and measurements of subjective visual vertical and cervical and ocular vestibular evoked myogenic potentials (VEMPs).Results:The head impulse gain of the vestibulo-ocular reflex (VOR) was decreased invariably for the contralesional posterior canal (PC) (n = 9; 90%) and usually for the ipsilesional horizontal canal (n = 5; 50%). At least one component of contraversive ocular tilt reaction (n = 9) or contraversive tilt of the subjective visual vertical (n = 7) were common along with ipsitorsional nystagmus (n = 5). Cervical or ocular VEMPs were abnormal in 5 patients.Conclusions:The MLF serves as the main passage for the high-acceleration VOR from the contralateral PC. The associations and dissociations of the vestibular dysfunction in our patients indicate variable combinations of damage to the vestibular fibers ascending or descending in the MLF even in strokes causing isolated unilateral INO.

Internuclear Ophthalmoplegia

2019 ◽  
pp. 133-136
Author(s):  
Matthew J. Thurtell ◽  
Robert L. Tomsak
Keyword(s):  
Clinical Features ◽  
Treatment Approach ◽  
Progressive External Ophthalmoplegia ◽  
Medial Longitudinal Fasciculus ◽  
Chronic Progressive External Ophthalmoplegia ◽  
Internuclear Ophthalmoplegia ◽  
Ocular Myasthenia ◽  
Common Causes ◽  
The Common

Internuclear ophthalmoplegia is characterized by an ipsilateral adduction deficit that can be overcome with convergence. It is caused by a lesion affecting the medial longitudinal fasciculus in the brainstem tegmentum. In this chapter, we begin by reviewing the clinical features of internuclear ophthalmoplegia. We next list the common causes of internuclear ophthalmoplegia, which include demyelination, stroke, tumors, and congenital hindbrain anomalies. We then discuss other potential causes of an adduction deficit that can mimic internuclear ophthalmoplegia, which include ocular myasthenia and chronic progressive external ophthalmoplegia, and describe strategies to help diagnose these at the bedside. Lastly, we briefly discuss the treatment approach for internuclear ophthalmoplegia.

Internuclear Ophthalmoplegia

2011 ◽  
pp. 102-105
Author(s):  
Matthew J. Thurtell ◽  
Robert L. Tomsak ◽  
Robert B. Daroff
Keyword(s):  
Differential Diagnosis ◽  
Medial Longitudinal Fasciculus ◽  
Internuclear Ophthalmoplegia ◽  
Ocular Motor

Internuclear ophthalmoplegia is a classic ocular motor syndrome that is caused by a lesion affecting the medial longitudinal fasciculus in the brainstem. In this chapter, we review the signs, causes, and differential diagnosis of internuclear ophthalmoplegia.

scholarly journals Bilateral internuclear ophthalmoplegia and clivus fracture following head injury: case report

2002 ◽  
Vol 60 (3A) ◽  
pp. 636-638 ◽  
Author(s):  
Leonardo Bonilha ◽  
Yvens Barbosa Fernandes ◽  
João Paulo de Vasconcelos Mattos ◽  
Wilson Adriano Abraão Borges ◽  
Guilherme Borges
Keyword(s):  
Head Injury ◽  
Brain Stem ◽  
Medial Longitudinal Fasciculus ◽  
Internuclear Ophthalmoplegia ◽  
Patient History ◽  
Rare Association ◽  
Image Investigation ◽  
Post Traumatic ◽  
Clivus Fracture ◽  
Stem Position

Internuclear ophthalmoplegia is a remarkable finding, particularly in patients victims of head injury. The medial longitudinal fasciculus, which is believed to be lesioned in cases of internuclear ophthalmoplegia, has an unique brain stem position and the mechanism involved in brain stem contusions implies a maximal intensity of shearing forces on the skull base. We describe a very rare association of bilateral ophthalmoplegia and clivus fracture following head injury, without further neurological signs. The patient history, his physical examination and the image investigation provide additional evidence to some of the mechanisms of injury proposed to explain post-traumatic internuclear ophthalmoplegia.

Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) syndrome in a patient with neuromyelitis optica spectrum disorder and anti-aquaporin-4 antibody

2011 ◽  
Vol 17 (7) ◽  
pp. 885-887 ◽  
Author(s):  
Koji Shinoda ◽  
Takuya Matsushita ◽  
Konosuke Furuta ◽  
Noriko Isobe ◽  
Tomomi Yonekawa ◽  
...  
Keyword(s):  
Neuromyelitis Optica ◽  
Spectrum Disorder ◽  
Aquaporin 4 ◽  
Medial Longitudinal Fasciculus ◽  
High Signal ◽  
Internuclear Ophthalmoplegia ◽  
Intensity Lesion ◽  
Multiple Sclerosis Patients ◽  
First Time ◽  
Aqp4 Antibody

This report describes, for the first time, an occurrence of wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) in a 19-year-old female with neuromyelitis optica (NMO) spectrum disorder, who had anti-aquaporin-4 (AQP4) antibody. A high signal intensity lesion on T2-weighted MRI was detected in the midbrain tegmentum adjacent to the aqueduct, and presumably involved the medial longitudinal fasciculus bilaterally at the caudal levels. Plasma exchange resolved both WEBINO syndrome and the midbrain lesion. Although WEBINO syndrome is occasionally reported in multiple sclerosis patients, diagnosis of NMO should not be excluded in patients with WEBINO syndrome, because AQP4 is expressed abundantly around the periaqueductal region.

scholarly journals An Anatomic, Imaging, and Clinical Review of the Medial Longitudinal Fasciculus

2020 ◽  
Vol 10 ◽  
pp. 83
Author(s):  
Peter Fiester ◽  
Saif Ahmed Baig ◽  
Jeet Patel ◽  
Dinesh Rao
Keyword(s):  
Brain Mri ◽  
Clinical Manifestations ◽  
Saccadic Eye Movements ◽  
Medial Longitudinal Fasciculus ◽  
Internuclear Ophthalmoplegia ◽  
Nerve Bundle ◽  
Comprehensive Understanding ◽  
Myelinated Nerve ◽  
Ocular Reflex ◽  
Vestibular Ocular Reflex

The medial longitudinal fasciculus (MLF) is a paired, highly specialized, and heavily myelinated nerve bundle responsible for extraocular muscle movements, including the oculomotor reflex, saccadic eye movements an smooth pursuit, and the vestibular ocular reflex. Clinically, lesions of the MLF are classically associated with internuclear ophthalmoplegia. However, clinical manifestations of a lesion in the MLF may be more complex and variable. We provide an overview of the neuroanatomy, neurologic manifestations, and correlative examples of the imaging findings on brain MRI of MLF lesions to provide the clinician and radiologist with a more comprehensive understanding of the MLF and potential clinical manifestations for an MLF lesion.

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