History of AVM treated with radiosurgery presents with burning smell sensation. There is no significant interval change in the overall size of the residual vascular malformation in the region of the vein of Galen, measuring up to 15 mm, as before, although the signal characteristics have evolved, with new areas of T1 and T2 hyperintensity. In addition, a portion of the lesion displays enhancement. Otherwise, there is no evidence of acute infarct or other intracranial mass lesions. The ventricles are unchanged in size and configuration. There is no midline shift or herniation. There is persistent scattered paranasal sinus mucosal disease. The orbits are intact.
The residual portion of the vein of Galen region vascular malformation is unchanged in size, but displays interval evolution of the signal characteristics and enhancement, which may represent an organizing hematoma or "Masson tumor". 