Neurosurgery for supratentorial brain tumor is frequently associated with preoperative intracranial hypertension. The evaluation of intracranial pressure is available noninvasively by measuring the diameter of the optic nerve sheath ultrasound.

The evaluation of intracranial pressure by measuring the DNO in perioperative is not described in the literature. The investigators propose a pilot study to assess intracranial pressure perioperative surgery for supratentorial brain tumor. The investigators consider a diameter of the optic nerve sheath as normal and predictive of intracranial pressure below 20 mm Hg when less than 5.7 mm (on the average of two measurements on each eye). DNO the normal healthy adult unanesthetized is 5 mm.

The main objective of the study is to compare the mean change in diameter of the optic nerve between the postoperative and D2 between groups of patients undergoing resection of a brain tumor and patients undergoing biopsy brain tumor.

Pilot Study: Prospective, single-center, controlled, non-randomized, the number of patients is estimated according to the recruiting capabilities of neurosurgery for this type of patient in the institution, A total of 40 patients: 20 patients Tumor Resection, control group: 20 patients Biopsy Brain Tumor.

Inclusion Criteria:

• Age ≥ 18 years
• Hospitalized for surgery of intracerebral tumors in the study group.
• Hospitalized for a biopsy of intracerebral tumor lesion in the control group.

Exclusion Criteria:

• Age <18 years
• Enucleation Prohibited to the achievement of an ocular ultrasound
• Hypersensitivity to gel
• Eye Wound
• Massive facial fracture
• Skin Infection Site