Natural Progression of Pineal Cysts in Relation to Headache: A Prospective Observational Study

Pineal cysts are a frequent, potentially incidental finding in routine imaging studies. Their relationship with headache has been a matter of some controversy. In this prospective observational study, we sought to track the clinical and radiological trajectory of pineal cysts in both patients with and without concurrent headache.

A cohort study was conducted in patients referred to the Department of Neurosurgery at Karolinska Hospital for evaluation of a pineal cyst ≥ 5 mm between June 2005 and April 2017. Patients were stratified according to headache status and classified according to standard criteria. Development in cyst size and degree of aqueduct stenosis, as well as clinical progression of headache, was tracked.

157 cysts were identified (50 males and 107 females, mean age: 37 years), 103 of which were in patients primarily assessed for headaches. Cyst size remained stable over the follow-up period. There was no relationship between cyst size, the presence or progression of headache, nor with amenability to treatment. No relationship between the mass effect of the quadrigeminal plate and headache was observed. Of 13 patients treated with melatonin, 7 (53%) reported a subsequent decrease in headache severity.

A major proportion of seemingly incidental pineal cysts referred for neurosurgical evaluation were detected during work-up for headache. Furthermore, the size and symptoms associated with cysts remain stable over time, barring intervention. The therapeutic implications and relationship with other factors such as melatonin remain to be explored.