“…They present as firm, solitary masses that slowly progress over months or years. 1,2,4,[6][7][8][9][10][11]13,15,16,19,20,25,28,33,34 Intracranial extension of a calvarial based intraosseous hemangioma is an infrequent occurrence. [1][2][3]5,13,14,19,20 Few prior reports have noted expansion of these lesions beyond the dural plane.…”