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Parinaud’s syndrome

1929

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).

A cluster of abnormalities of eye movement and pupil dysfunction, characterized by:

Paralysis of upwards gaze.

Downward gaze is usually preserved.

This vertical palsy is supranuclear.

The doll’s head maneuver should elevate the eyes, but eventually all upward gaze mechanisms fail.

Pseudo-Argyll Robertson pupils are associated with accommodative paresis, and pupils become mid-dilated and show light-near dissociation.

Attempts at upward gaze often produce convergence retraction nystagmus in pinealomas, multiple sclerosis and brainstem infarction.

The syndrome is classically associated with three major groups:

Young patients with brain tumors in the pineal gland or midbrain.

Piinealoma are the most common lesion producing this syndrome.

Women in their 20s-30s with multiple sclerosis.

Older patients following stroke of the upper brainstem

Compression 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.

Parinaud syndrome is due to compression of the quadrigeminal plate, where the neural centers coordinating the conjugated vertical eye movement are located.

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.

Neoplasms and giant aneurysms of the posterior fossa have also been associated with the midbrain syndrome.

Metabolic disorders, such as Niemann-Pick disease, Wilson’s disease, kernicterus, and barbiturate overdose have also been associated with vertical supranuclear ophthalmoplegia

Treatment is directed towards etiology of the dorsal midbrain syndrome.

Neuroimaging is essential to define anatomic lesions or other causes of this syndrome.

Management of upgaze palsy, retraction nystagmus and convergence movement can be relieved with bilateral inferior rectus resections.

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.

Rapid resolution after normalization of intracranial pressure following placement of a ventriculoperitoneal shunt has been reported.