Investigators want to know the natural history of the vestibular schwannomas: increasing, decreasing or stability, by monitoring more than 3 MRIs during a span of more than 2 years. They will obtain 3 groups: the volume increasing schwannomas which will be the most important group, the schwannomas that will be stable and a small group where the schwannomas will decrease.

The secondary purpose is that the investigators want to know the threshold values: a minimum volume under which we are sure that the schwannoma will not increase, a maximum value where it will increase and if its evolution can be correlated to clinical or radiological criteria.

Inclusion Criteria:

• Age over 18 years
• having a typical vestibular schwannoma diagnosis during the first MRI, having a minimum of 3 internal auditory canal MRIs on the same machine (Signa HDxt, General Electric, Strasbourg, France) ) at the Hôpitaux Universitaires de Strasbourg
• patients consenting to participate

Exclusion Criteria:

• intra-labyrinthical extension
• treatment before the 3 MRIs
• no injection of gadolinium
• atypical diagnosis

Patients having a typical vestibular schwannoma diagnosis during the first MRI, having a minimum of 3 internal auditory canal MRIs on the same machine (Signa HDxt, General Electric, Strasbourg, France) ) at the Hôpitaux Universitaires de Strasbourg