JUSTIFICATION Anti-epileptic prophylaxis has long been a systematic practice for supra-tentorial intracranial surgeries. Since 2021, European guidelines no longer recommend this prophylaxis and practices have evolved.

We therefore propose to compare epileptic seizure's occurrence in the first postoperative month between two groups of neurosurgical patients.The first group consists of patients treated between January 2019 and late 2020 who were given systematic prophylaxis. Patients from the second group were treated between 2021 and 2022 and did not receive any prophylaxis.

The secondary objective will consist in identifying the number of patients placed on prophylaxis, the length of prophylaxis, treatment's side effects (depression, elevated liver enzymes…), and comparing patients' neurological outcome at 3 and 6 months after surgical procedures.

Inclusion Criteria:

• Adults over 18 years old
• Expressed non-opposition
• Patient who underwent supratentorial intracranial surgery (either resection or biopsy) at Brest University Hospital from January 01, 2019 to September 01, 2022.

Exclusion Criteria:

• Refusal to participate
• Patient under legal protection

Patients underwent a supratentorial intracerebral elective surgery (resection or biopsy) over the period from January 01, 2019 to September 01, 2022.

All collected data that underlie results in a publication

Data will be available beginning three years and ending fifteen years following the final study report completion

Data access requests will be reviewed by the internal committee of Brest UH. Requestors will be required to sign and complete a data access agreement.