Chapter contents Overview Origin & central course Intracranial course Final innervation Coordination of muscles Lower motor neuron lesion Upper motor neuron lesion MLF syndrome

Cranial Nerve VI - Abducens Nerve Page 8 of 8 Clinical correlation - MLF syndrome Assuming the lateral gaze center is intact, damage to the medial longitudinal fasciculus (MLF) between the pons and occulomotor nucleus will result in a defect in lateral gaze. On attempting lateral gaze: Due to loss of input to the occulomotor nucleus from the lateral gaze center, the adducting eye is unable to move medially past approximately the midline of gaze. Monocular horizontal nystagmus is observed for the abducting eye. The abducting eye moves smoothly laterally followed by a rapid movement (saccade) back to midline gaze. MLF syndrome is most often seen in patients with multiple sclerosis due to demyelination of the MLF tract. Figure 6-8. MLF syndrome.

Last revised: March 22, 1998