The injection of autologous blood Blood Patch (BP) into the epidural space is the standard treatment for headache associated with intracranial hypotension. It provokes cerebral vasoconstriction. It is cons-indicated in a number of situations (HIV positive, fever, sepsis, leukemia). The purpose of this study is to evaluate another technique using a patch made by injecting an epidural hydroxyethylstarch solution (HES 130, 0.4, 6%) instead of blood patch. This alternative technique is simple to implement and does not have some of the specific blood pressure contra-indications. The study aims at comparing the "Blood Patch" group versus the "HES Patch" in terms of clinical efficacy , tolerance, satisfaction of the anesthetist, ease of implementation and effect of the injection of epidural anesthesia on cerebral blood flow within 24 hours.

Inclusion Criteria:

• Subjects older than 18 years.·
• Subjects with an intracranial hypertension syndrome secondary to an epidural, spinal or lumbar puncture (and therefore presumed iatrogenic) with a sub arachnoid space or subjects with intracranial hypertension syndrome of primitive origin requiring treatment with epidural Patch ·
• subjects with a temporal window of sufficient quality to carry out the transcranial Doppler ·
• Subjects haven read the informed consent, signed and dated prior to the start of any proceedings related to the tial·
• Subjects affiliated to health insurance·
• Subjects having been informed of the results of a prior medical consultation

Exclusion Criteria:

• Subjects with a cons-indication to an epidural Patch:
• blood disorders constitutional or acquired coagulation with platelets
• Subjects under treatment with curative doses of antiplatelet drugs or anticoagulants
• subjects under shock and / or hypovolemia
• subjects under generalized sepsis or at the puncture site
• any other cons-indication to performing an epidural