Inclusion Criteria:  Age between 18 and 65 years  Decompressive hemi-craniectomy planed for*:  Impairment of consciousness or progressive reduction of consciousness and Mass effect on brain imaging (oedema exceeding 50% of the MCA territory and midline shift), and Exclusion of other causes of impaired consciousness (e.g. hypoperfusion, hypotension, cerebral reinfarction, epileptic seizures Informed consent from relatives  Exclusion Criteria:  Bilateral, nonreactive, not drug-induced pupillary dilation, associated with coma*  Simultaneous presence of all four of the following unfavorable prognostic factors: *  Age 50 years Involvement of additional vascular territories Unilateral pupillary dilation GCS<8 Severe comorbidity (severe heart failure or myocardial infarction, incurable neoplasia, etc. * Refusal by the patient of this treatment, as known from current interaction with the patient, from existing written documents or related by the patient's proxies. * Known pulmonary or cranial infection Any coagulopathy Rapid neurological decline prohibiting the extra time needed for space flab production (10min) Pregnancy