Symptomatic Pineal Cysts Without Ventricular Enlargement: Diagnosis and Treament.

Background: Pineal cysts that are not associated with ventricular enlargement can lead to manifestations of intracranial hypertension, usually paroxysmal. If these are due to local mass effect or narrowing of the entrance to the aqueduct, surgery may be indicated.

Methods: This is a narrative review based on publications retrieved by a search in PubMed.

Results: Autopsy studies have revealed pineal cysts in 40% of subjects. Pineal cysts that are not associated with ventricular enlargement can cause intermittent attacks of headache; the second most common symptom is visual disturbance. Patients often also report many non-specific symptoms such as dizziness, fatigue, lethargy, drowsiness, a decline in performance, gait disturbances, impaired memory, or sleep disorders. Because the symptoms are often nonspecific and pineal cysts are common, surgery should not be performed on a pineal cyst unless a comprehensive diagnostic work-up for other potential causes has been carried out with the aid of specialists in all relevant disciplines. In multiple clinical studies, the rate of total relief of symptoms by surgery ranged from 46.8% to 96.4%, while the rate of partial relief ranged from 3.6% to 47.6% and that of persistent symptoms from 3.3% to 18.8%. Permanent complications are rare.

Conclusion: If there are manifestations of intracranial hypertension that are clearly attributable to the pineal cyst, such as severe, holocephalic headaches, vomiting (usually projectile), and brainstem signs that can be triggered by the Valsalva maneuver, and if no other cause of these manifestations can be identified, surgery has a high likelihood of success. A prerequisite to surgical treatment is that the MRI reveals that the pineal cyst is exerting mass effect and/or narrowing the entrance to the aqueduct, even if the ventricles are not enlarged. Because pineal cysts are common and have nonspecific manifestations, surgery must only be performed for strict indications. It should be noted that only low-level evidence supports surgical treatment.