 Low-grade glioma is a malignant tumor of young adults 12.5 of gliomas, incidence of 0.99 100,000. Median survival, linked to anaplastic transformation is estimated between 7 and 10 years, with great individual variability in the rate of evolution. The morphological MRI, standard assessment tool at present, suffers from many limitations, especially concerning the positive diagnosis, the targeting of surgical biopsies and tumor delineation which is essential to treatment The study design is a validation study of a new diagnostic procedure. This study is prospective, no randomized, multicenter involving 10 centers Toulouse University Hospital, Caen, Tours, AP-HP Pitie Salpetriere, Lille, Angers, Rennes, Nîmes, Nantes and Nancy. Will be eligible patients in whom the diagnosis of grade II glioma is suspected according to clinical data and MRI, after evaluation and multidisciplinary meeting at which histological confirmation is scheduled within a maximum period of one month. 