Dural Calcifications: Normal Locations and Appearances

Abstract

Normal physiologic calcifications of the dura increase in frequency with increasing age and are typically not of any clinical significance. They are particularly common among the elderly and are rare in children. However, in children they can be related to an underlying etiology or metabolic disorder, while in adults they are considered abnormal only if they are marked and progressive. Etiologies that may lead to the abnormally progressing dural calcifications include underlying inflammation or fibrosis such as arises from chronic subdural hematoma (SDH), dural osteoma, intracranial hypotension, sarcoidosis, tuberculosis, hyperparathyroidism, basal cell nevus syndrome (in children), chronic involvement by lymphoma or plasmacytoma (or any other tumor that invades the dura mater), chronic renal failure, or rarely, nephrogenic systemic fibrosis. It should be noted that since extra-axial lesions can cause hyperostosis or dural calcification as a reactive phenomenon, the presence of dural calcifications should alert the radiologist to exclude an adjacent mass. However, the overwhelming majority of dural calcifications are physiologic, particularly in the elderly. Such calcifications may enlarge very slowly. Dural calcifications may also occur in conjunction with hyperostosis of the calvarial bones, most commonly along the vertex of the skull (especially hyperostosis frontalis) or even along the inner aspect of the sphenoid or temporal bones.