A conjugated palsy refers to the inability to move both eyes in a particular horizontal (most common) or vertical direction.
Paresis view mostly concern the horizontal eye movement; some affect the Aufblick, rarely the downgaze is affected.
A conjugated palsy refers to the inability to move both eyes in a particular horizontal (most common) or vertical direction. Paresis view mostly concern the horizontal eye movement; some affect the Aufblick, rarely the downgaze is affected. Horizontal viewing paresis Conjugated horizontal viewing movements are controlled by neural impulses from the cerebral hemispheres, the cerebellum, the vestibular nuclei and the neck region. The neural input from these regions converge at the center of horizontal eye movements (paramedian pontine reticular formation) and is integrated to a final command to the adjacent core of VI. Cranial nerve, which controls the ipsilateral lateral rectus muscle on the medial longitudinal fasciculus, and to the core of the contralateral III. Cranial nerves, which in turn controls the medial rectus muscle. Inhibitory signals to opposite eye muscles occur simultaneously. The most common and most debilitating restriction of horizontal viewing movements resulting from pontine lesions, the Center for horizontal viewing movements and the core of the VI. Cranial nerves affect them. Stroke is a common cause, leading to failure of the horizontal eye movements ipsilateral to the lesion. For paralysis due to stroke, it may happen that the eyes can not move in response to a stimulus itself (eg. As arbitrary or vestibular). Easier paralysis can cause nystagmus or fixation weakness only. Another common reason is frontal lesion in the contralateral cerebral hemisphere rostral gyrus. These lesions are typically caused by a stroke. The resulting paralysis usually regresses with time back. Conjugated horizontal eye movements which are mediated by the brain stem reflexes (z. B. in response to caloric stimulation with cold water) are obtained. Vertical gaze palsy up and downgaze depend on the input of the nerves that rise and of the vestibular system by the medial longitudinal fasciculus on both sides of the nuclei of the III. run and IV. cranial nerve, interstitial Cajal-core and the rostral interstitial nucleus of the medial longitudinal fasciculus. A separate system is believed to proceed by the descending Grohßhirnhemisphären by the Prätektum the midbrain to the nuclei of the III. and IV. cranial nerves. The interstitial rostral nucleus of the medial longitudinal fasciculus integrated neuronal input to a final command for vertical eye movements. Vertical eye movements are limited with aging. Frequently vertical gaze palsy arise as a result of the midbrain lesions, usually by infarction or tumors. In vertical paresis of Aufblicks the pupil can be expanded, and when Aufblick a vertical nystagmus occurs. The Parinaud syndrome (dorsal midbrain syndrome), a conjugated paresis of Aufblicks may originate from a Pinealistumor or, more rarely, a tumor or infarct of the Prätektum in the midbrain. This syndrome is characterized by a disturbed Aufblick, lid retraction (Collier mark), downward view preference (Sunset phenomenon), convergence-retraction nystagmus and dilated pupils (about 6 mm), which respond poorly to light, but better (on accommodation light near dissociation). Paresis of Abblicks A troubled downgaze with preserved Aufblick displays a progressive supranuclear palsy generally; other causes are rare.