However, a condition called Reverse Parinaud syndrome has also been described. This makes them more susceptible to the pressure effect of space occupying lesions. It has been suggested that the pathways for downward gaze are directed medially from the rostral interstitial nucleus of the Medial Longitudinal Fasciculus whereas, the fibers for upward gaze are directed laterally from the Medial Longitudinal Fasciculus and decussate in the posterior commissure. Downgaze is classically preserved, but the reason for this is not entirely explained. It occurs because of the involvement of the vertical gaze centers, which are in proximity to the superior colliculus, with some of the main nuclei being the interstitial nuclei of Cajal and the rostral interstitial nucleus of the Medial Longitudinal Fasciculus. The characteristic symptom of Parinaud syndrome is limited conjugate upgaze. Also, it may sometimes include conjugate downgaze in primary position and rarely downgaze palsy 2. However, the definition of Parinaud syndrome has now been widened to include the triad of upgaze paralysis, convergence retraction nystagmus, and pupillary light-near dissociation. The classic triad of upgaze paly, convergence retraction nystagmus and pupillary light-near dissociation was seen in about 65% of patients with Parinaud’s syndrome. The original description by Henri Parinaud included upgaze palsy and convergence paralysis. Neurosurgeons will often see this sign most commonly in patients with failed ventriculoperitoneal shunts. Conjugate down gaze in the primary position: “setting-sun sign”.The easiest way to bring out this reaction is to ask the patient to follow down-going stripes on an optokinetic drum. On fast up-gaze, the eyes pull in and the globes retract. Convergence-Retraction nystagmus: Attemps at upward gaze often produce this phenomenon.Pseudo-Argyll Robertson pupils: Accommodative paresis ensues, and pupils become mid-dilated and show light-near dissociation.This vertical palsy is supranuclear, so doll’s head maneuver should elevate the eyes, but eventually all upward gaze mechanisms fail. Paralysis of upgaze: Downward gaze is usually preserved.Parinaud syndrome also known as Sylvian aqueduct syndrome, dorsal midbrain syndrome, pretectal syndrome, and Koerber-Salus-Elschnig syndrome is a cluster of abnormalities of eye movements and pupil dysfunction, characterized by 1: Rapid resolution after normalization of intracranial pressure following placement of a ventriculoperitoneal shunt has been reported.Parinaud syndrome prognosis Parinaud syndrome Parinaud’s syndrome generally improve slowly over months, especially with resolution of the causative factor, but continued resolution after the first 3–6 months of onset is uncommon. Management of upgaze palsy, retraction nystagmus and convergence movement can be relieved with bilateral inferior rectus resections. Neuroimaging is essential to define anatomic lesions or other causes of this syndrome. Treatment is directed towards etiology of the dorsal midbrain syndrome. Metabolic disorders, such as Niemann-Pick disease, Wilson’s disease, kernicterus, and barbiturate overdose have also been associated with vertical supranuclear ophthalmoplegia Neoplasms and giant aneurysms of the posterior fossa have also been associated with the midbrain syndrome. Other compressions due to ischemia or damage to this region can produce these findings: obstructive hydrocephalus, midbrain hemorrhage, cerebral arteriovenous malformation, trauma, brainstem toxoplasmosis infection. Parinaud syndrome is due to compression of the quadrigeminal plate, where the neural centers coordinating the conjugated vertical eye movement are located. Older patients following stroke of the upper brainstemĬompression or ischemic damage of the mesencephalic tectum, including the superior colliculus adjacent oculomotor and Edinger-Westphal nuclei, are involved causing dysfunction to the motor function of the eye. Women in their 20s-30s with multiple sclerosis. Piinealoma are the most common lesion producing this syndrome. Young patients with brain tumors in the pineal gland or midbrain. The syndrome is classically associated with three major groups: Pinealomas, multiple sclerosis and brainstem infarction. Pseudo-Argyll Robertson pupils are associated with accommodative paresis, and pupils become mid-dilated and show light-near dissociation.Īttempts at upward gaze often produce convergence retraction nystagmus in The doll’s head maneuver should elevate the eyes, but eventually all upward gaze mechanisms fail. Refers to an inability to move the eyes up and down, caused by compression of the vertical gaze center at the rostral interstitial nucleus of medial longitudinal fasciculus (riMLF).Ī cluster of abnormalities of eye movement and pupil dysfunction, characterized by:
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