Learn all about Parinaud syndrome definition, symptoms, causes and treatment options.
Parinaud’s Syndrome is a cluster of abnormalities of eye movement and pupil dysfunction. Named after Henry Parinaud, a French ophthalmologist (1844-1905) considered to be the father of French ophthalmology. The dorsal midbrain syndrome is also known as Parinaud’s syndrome, sylvian aqueduct syndrome, or pretectal syndrome. Over 80% of patients with pineal tumors at presentation have features of raised intracranial pressure due to blockage of the sylvian aqueduct. They may also present with hypothalamic syndrome.
Conjugate down gaze in the primary position: “setting-sun sign”. Neurosurgeons see this sign most commonly in patients with failed hydrocephalus shunts. Parinaud’s syndrome, includes multiple clinical signs, with the most prominent being paralysis of upward gaze.
It is also commonly associated with bilateral papilledema. It has less commonly been associated with spasm of accommodation on attempted upward gaze, pseudo abducens 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.
Parinaud syndrome is a rare condition that’s still not fully understood by doctors. However, it’s usually related to a problem affecting the midbrain area, such as a tumor or infection. Tell your doctor about all of your symptoms, even if they don’t seem related to your eyes. This will help them narrow down any underlying causes.
What is Parinaud Syndrome?
Parinaud syndrome, also known as the dorsal midbrain syndrome, is a supra nuclear vertical gaze disturbance caused by compression of the tectal plate. Parinaud Syndrome is a set of eye abnormalities associated with eye movement anomalies and pupil dysfunction. Parinaud syndrome is an eye problem that is similar to conjunctivitis. It usually affects only one eye and occurs with swollen lymph nodes and an illness with a fever
Parinaud Syndrome Definition
Parinaud syndrome is also known as dorsal midbrain or collicular syndrome. The lesion is in the rostral dorsal midbrain, damaging the superior colliculi and pretectal structures. Patients report difficulty in looking up and blurring of distant vision.
Parinaud Syndrome Symptoms
Parinaud syndrome has many symptoms associated with it. While the main symptom of Parinaud syndrome is not being able to look up or down, you may notice other eye problems as well. These include:
• pseudo-Argyll Robertson pupils, pupils which reduce in size on a near object
• pupil’s not responding to light
• uncontrollable, jerky eye movements, sometimes called convergence retraction nystagmus
• retraction of your eyelids
• blurry vision
Depending on the underlying cause, you may notice other symptoms not related to your eyes, such as:
• near vision becomes blurred
• Associated symptoms related to neurological
• slurred speech
• weak legs
• gait issues
• hand tremors
• Muscle spasms.
Parinaud Syndrome Causes
Parinaud syndrome is caused by an infection by bacteria, virus, fungus, or a parasite. The most common causes are cat-scratch disease and tularemia. The bacteria that cause either condition can infect the eye. Either the bacteria can directly enter the eye (on a finger or other object), or air droplets that carry the bacteria can land on the eye.
Other infectious diseases may spread this same way, or through the bloodstream to the eye. Causes include tumors of the pineal gland, stroke, hemorrhage, trauma, hydrocephalus, or multiple sclerosis. The upgaze palsy can be mimicked by progressive supra nuclear palsy, thyroid ophthalmopathy, myasthenia gravis, Guillain-Barre syndrome, or congenital upgaze limitation. The causes of Parinaud syndrome include pineal gland tumors, midbrain infarctions, multiple sclerosis, midbrain hemorrhage, encephalitis, arteriovenous malformations, infections (toxoplasmosis), trauma, obstructive hydrocephalus, and sometimes, tonic-clonic seizures.
There have been reports of this condition following brachytherapy instillation. However, the most common causes are a pineal gland tumor and other midbrain pathologies like hemorrhage and infarction. The underlying cause of Parinaud syndrome is also found to vary with age. Neoplastic causes are more common in children and young adults, and vascular causes are more common in the middle-aged and older populations.
Parinaud Syndrome Treatment
Parinaud syndrome treatment mainly depends upon the underlying cause of the disease, as different etiologies can involve in dorsal midbrain syndrome. A detailed diagnosis including neuro-imaging like CT scan and MRI tests are essential to diagnose the actual reason of dorsal midbrain syndrome. The eye findings of Parinaud’s syndrome generally improve slowly over months, especially with resolution of the causative factor; continued resolution after the first 3-6 months of onset is uncommon. However, rapid resolution after normalization of intracranial pressure following placement of a ventriculoperitoneal shunt has been reported.