AKT1 and meningioma: None of the AKT1-mutant meningiomas showed calcifications in the preoperative MRI or CT scan, whereas all calcified meningiomas (n = 17) harbored a NF2 mutation (p = 0.0002). Several prior reports have discussed tumor calcification as a potential risk for permanent neurological deterioration due to difficult surgical removal [9, 12].