A trepanation model in the rat cranium is represented starting from the permanent enlargement of the microneurosurgical interventions with the necessity of trepanation below the microscope, the suture of the dura mater in regions with difficult access, and the dressing of cerebral tissue defects. A possibility for the microsurgical training is given for the trepanation and the dressing of dural and cerebral defects. Surgical materials and/or drugs for local application can be tested for using them in the neurosurgery too.