Imaging features of hyperostosis frontalis interna / 中华神经医学杂志

ABSTRACT

Objective:To explore the imaging features of hyperostosis frontalis interna (HFI).Methods:One hundred patients with clinically diagnosed HFI were enrolled from Department of Radiology, Yueqing People's Hospital and Department of Imaging, Wenzhou People's Hospital from January 2011 to December 2022. MRI alone was performed in 45 patients; MRI+DR was performed in 14, and MRI+CT was performed in 41. The imaging features of these patients were analyzed retrospectively.Results:In these 100 patients, 20 were with external hyperplasia, 51 with internal hyperplasia, and 29 with intermediate hyperplasia. External hyperplasia manifested as proliferating towards the diploe, enjoying clear boundary, uniform high signals of the hyperplastic inner plate and diploe on T1WI and T2WI, and high density of the hyperplastic inner plate and diploe on CT and DR. Internal hyperplasia manifested as proliferating towards the cranial cavity, enjoying wavy or nodular inner edges, non-uniform low signals of hyperplastic inner plate on T1WI and T2WI, and high density of the hyperplastic inner plate on CT and DR. Intermediate hyperplasia manifested as proliferating simultaneously towards the cranial cavity and diploe, enjoying thin and blurred diploe, uniform or non-uniform high signals of the hyperplastic inner plate and diploe on T1WI and T2WI, and non-uniform high density of the hyperplastic inner plate and diploe on CT and DR. Compressed and displaced brain parenchyma, reduced anterior cranial fossa volume, and narrowed subarachnoid space were noted in these 100 patients, including 47 patients with obvious frontal lobe brain tissue compression (depth of 3.0-17 mm, averaged [8.6±5.9] mm), 35 with lacunar cerebral infarction, 33 with subcortical arteriosclerotic encephalopathy, and 32 with varied degrees of cerebral atrophy.Conclusion:HFI is characterized by thickening and hardening of the bilateral frontal bone inner plates, with wavy, nodular or spindle-shaped inner edges, compressed brain tissues, and reduced anterior cranial fossa; these imaging features can help the definite diagnosis of HFI.