Lesions that involve the paramedian pontine reticular formation (PPRF) or the sixthnerve nucleus on one side of the brain stem and also interrupt internuclear fibers of the ipsilateral medial longitudinal fasciculus produce an ipsilateral horizontal gaze palsy combined with an internuclear ophthalmoplegia, so that the only preserved horizontal eye movement is abduction of the contralateral eye ...

Eye movements bring visual stimuli to the fovea and also maintain foveal fixation on a moving target and during head movements. These movements are performed by the ocular motor system that consists of ocular motor nerves and nuclei in the brainstem originating in the cerebral cortex, cerebellum, vestibular structures, and the extraocular muscles. The ocular motor system is divided according to...

A 42 year old man presented with a slowly progressive gait disturbance, generalised weakness, dysarthria, clumsiness and tremor of his hands, and involuntary jerks. Hexosaminidase A activity in plasma, leucocytes and fibroblasts was considerably reduced, establishing the diagnosis of GM2 gangliosidosis. Clinical examination showed two previously unreported features, a clinically evident sensory...

J.S. Kim, MD S.-H. Jeong, MD Y.-M. Oh, MD Y. Soon Yang, MD S.Y. Kim, MD A 78-year-old man with hypertension and diabetes was referred because of 3 days of diplopia and ophthalmoplegia. Neurologic examination disclosed exotropia of both eyes (wall-eyed) and bilateral internuclear ophthalmoplegia (WEBINO) with impaired convergence (figure, A).1 Vertical saccades and smooth pursuit were also limit...