What is a common cause of Parinaud syndrome?

Parinaud syndrome, also known as dorsal midbrain syndrome, is characterized by a specific set of neurological signs, including limitation of upward gaze, light-near dissociation, and convergence-retraction nystagmus. The most common cause of Parinaud syndrome is a lesion in the dorsal midbrain, which can arise from a tumor in the pineal gland.

The pineal gland is located in the brain near the superior colliculus, which is involved in eye movements. When a tumor (often a germinoma) develops in this region, it can exert pressure on nearby structures and disrupt the normal functioning of the midbrain, leading to the clinical features seen in Parinaud syndrome.

While other conditions could potentially cause similar symptoms, they are less common. Brain hemorrhage could result in midbrain involvement but is not a typical presentation of Parinaud syndrome. Meningitis might lead to other signs of increased intracranial pressure or meningeal irritation but does not specifically cause the eye movement abnormalities associated with this syndrome. Chronic headaches are nonspecific and do not directly relate to the neurological deficits characteristic of Parinaud syndrome. Therefore, a pineal gland tumor is recognized as a classic cause of this syndrome, making it