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Parinaud's Syndrome, also known as dorsal midbrain syndrome and vertical gaze palsy, is an inability to move the eyes up. It is caused by a tumor of the pineal gland which compresses the vertical gaze center at the rostral interstitial nucleus of medial longitudinal fasciculus (riMLF). The eyes lose the ability to move upward. It is a group of abnormalities of eye movement and pupil dysfunction. It is caused by lesions of the upper brain stem and is named for Henri Parinaud〔H. Parinaud. Paralysie des mouvements associés des yeux. Archives de neurologie, Paris, 1883, 5: 145-172.〕 (1844–1905), considered to be the father of French ophthalmology. ==Signs and symptoms== Parinaud's Syndrome is a cluster of abnormalities of eye movement and pupil dysfunction, characterized by: # Paralysis of upgaze: Downward gaze is usually preserved. This vertical palsy is supranuclear, so doll's head maneuver should elevate the eyes, but eventually all upward gaze mechanisms fail.〔(Neuro-Ophthalmic Examination )〕 # Pseudo-Argyll Robertson pupils: Accommodative paresis ensues, and pupils become mid-dilated and show light-near dissociation. # Convergence-Retraction nystagmus: Attempts at upward gaze often produce this phenomenon. On fast up-gaze, the eyes pull in and the globes retract. The easiest way to bring out this reaction is to ask the patient to follow down-going stripes on an optokinetic drum. # Eyelid retraction (Collier's sign) # Conjugate down gaze in the primary position: "setting-sun sign". Neurosurgeons will often see this sign most commonly in patients with failed ventriculoperitoneal shunts. It is also commonly associated with bilateral papilledema. It has less commonly been associated with spasm of accommodation on attempted upward gaze, pseudoabducens palsy (also known as thalamic esotropia) or slower movements of the abducting eye than the adducting eye during horizontal saccades, see-saw nystagmus and associated ocular motility deficits including skew deviation, oculomotor nerve palsy, trochlear nerve palsy and internuclear ophthalmoplegia. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Parinaud's syndrome」の詳細全文を読む スポンサード リンク
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