Epilepsy in patients with pineal gland cyst

The aim of the study is to describe types of epileptic seizures in patients with pineal gland cyst (PGC) and their outcome during follow up period (6-10 years). We wanted to determine whether patients with epilepsy differ in PGC volume and compression of the PGC on surrounding brain structures compared to patients with PGC, without epilepsy.

We analyzed prospectivelly 92 patients with PGC detected on magnetic resonance (MR) of the brain due to various neurological symptoms during the period 2006-2010. Data on described compression of the PGC on surrounding brain structures and size of the PGC were collected.

29 patients (16 women, 13 men), mean age 21.17 years had epilepsy and PGC (epilepsy group). 63 patients (44 women, 19 men), mean age 26.97 years had PGC without epilepsy (control group). Complex partial seizures were present in 8 patients, complex partial seizures with secondary generalization in 8 patients, generalized tonic clonic seizures (GTCS) in 10 and absance seizures in 3 patients. Mean PGC volume in epilepsy group was 855.93 mm³, in control group 651.59 mm³. There was no statistically significant difference between epilepsy and control group in PGC volume. Compression of PGC on surrounding brain structures was found in 3/29 patients (10.34%) in epilepsy group and in 11/63 patients (17.46%) in control group with no statistically significant difference between epilepsy and control group. All patients with epilepsy were put on antiepileptic therapy (AET). During the follow up period, 23 patients (79.31%) were seizure free, 3 patients (13.04%) had reduction in seizure frequency, whereas 3 patients had no improvement in seizure frequency. Two patients from epilepsy group and 3 patients from control group were operated with histologically confirmed diagnosis of PGC in 4, and pinealocytoma in 1 patient.

In patients with PGC, epileptic seizures were classified as: complex partial seizures (with or without secondary generalization), GTCS and absance seizures. All patients were put on AET. During follow up period 79.31% patients were seizure free. There was no difference in PGC volume, nor in described compression of the PGC on surrounding brain structures between epilepsy and control group. Based on our findings, pathomechanism of epileptic seizures in patients with PGC cannot be attributable solely to PGC volume or described compression on surrounding brain structures based on MRI findings.