The aim of the current study is to evaluate, in a prospective cross-over, randomized study, the effect of hyperbaric oxygen therapy (HBOT) on patients with chronic impairment after low grade glioma tumor removal surgery

Inclusion Criteria:

• Post low grade glioma (WHO I-II) removal surgery 3-12 months prior to the inclusion in the study.
• All patients have to have persistent cognitive impairment (Mindstream score should be at least one SD lower than average) regarding without noticeable improvement during the last month prior to their enrolment.
• Age 18 years or older.

Exclusion Criteria:

• Dynamic neurologic/cognitive improvement or worsening during the past month; Previous brain radiotherapy and/or radiosurgery. Steroids dependence Chemotherapy in the past month or scheduled in the next 3 months Seizures 1 month previous to inclusion Had been treated with HBOT for any other reason 1 month prior to inclusion; Have any other indication for HBOT; Chest pathology incompatible with pressure changes; Inner ear disease; Patients suffering from claustrophobia; Inability to sign written informed consent; Smoking patients will not be allowed to smoke during the study and if they would not comply with this demand they will be excluded.