What is one of the two major clinical symptoms of pineal gland masses?

Parinaud syndrome is a key clinical symptom associated with pineal gland masses due to the anatomical location of the pineal gland and its relation to the midbrain. When a mass develops in the pineal region, it can exert pressure on the aqueduct of Sylvius, leading to obstructive hydrocephalus, which is often accompanied by classic signs of Parinaud syndrome. This includes vertical gaze palsy, which makes it difficult for the patient to look up or down, along with other features such as eyelid retraction (Collier's sign) and convergence-retraction nystagmus. The symptoms arise from disruption in the pathways that control eye movements, highlighting the significant impact of a pineal mass on neurological function.

Other symptoms associated with pineal gland lesions may include seizures or visual impairment, but Parinaud syndrome specifically relates to the pressure effects on the brain structure associated with the pineal gland. Increased appetite is not typically linked to these masses or their effects on the central nervous system, making these other options less relevant in the context of the primary symptoms of pineal gland masses.