1. Department of Neurosurgery, Sainte Anne Military Hospital , Toulon 83 000, France
2. Department of Neurosurgery, Percy Military Hospital , Clamart 92 140, France
3. Department of Intensive Care, Sainte Anne Military Hospital , Toulon 83 000, France
4. French Military Health Service Academy, Ecole du Val-de-Grace , Paris 75 005, France