PT - JOURNAL ARTICLE AU - J.J. Waterval AU - T.M. van Dongen AU - R.J. Stokroos AU - B.-J. De Bondt AU - M.N. Chenault AU - J.J. Manni TI - Imaging Features and Progression of Hyperostosis Cranialis Interna AID - 10.3174/ajnr.A2830 DP - 2011 Dec 22 TA - American Journal of Neuroradiology 4099 - http://www.ajnr.org/content/early/2011/12/22/ajnr.A2830.short 4100 - http://www.ajnr.org/content/early/2011/12/22/ajnr.A2830.full AB - BACKGROUND AND PURPOSE: HCI is a unique autosomal-dominant sclerosing bone dysplasia affecting the skull base and the calvaria, characterized by cranial nerve deficits due to stenosis of neuroforamina, whereby the mandible is affected to a lesser extent. The aim of this study is to describe the specific radiologic characteristics and course of the disorder. MATERIALS AND METHODS: CT scans of affected individuals within 1 family were analyzed and compared with scans of their unaffected family members and with an age- and sex-matched control group. Linear measurements were performed of the inner table, the medulla, and the outer table of different skull locations, and attenuation (density) measurements of the same regions were recorded. Neuroforamina widths were recorded as well. RESULTS: There was significant thickening of the skull in the frontal, parietal, temporal, and occipital regions, which was mainly due to thickening of the inner table of the skull. The attenuation of the deposited hyperostotic bone was lower than normal cortical bone. CONCLUSIONS: HCI is the only genetic bone dysplasia known that is confined to the craniofacial area. The hyperostotic bone is less attenuated than normal cortical bone. The observed radiologic abnormalities explain the possible impairment of the olfactory, optic, trigeminal, facial, and vestibulocochlear nerves. Abbreviations ANCOVAanalysis of covarianceHCIhyperostosis cranialis internaHUHounsfield unitsIACinternal auditory canal