Hyperostosis frontalis interna, an incidentaloma on skull computed tomograms in a Sub-Saharan African tertiary hospital

Abstract

Background: Hyperostosis frontalis interna (HFI) is bony accretion of the inner table of the frontal calvarium. It is an incidental, asymptomatic and benign lesion seen mostly in postmenopausal females.
Aims: To determine the epidemiology of hyperostosis frontalis interna in Uyo using computed tomograms of the skull.
Methodology: Retrospective study of patients who underwent skull computed tomograms (CT) in University of Uyo teaching hospital (UUTH), Uyo, Nigeria from 13th November, 2013 to 31st May, 2019 was done. Data were acquired from archived medical records in Radiology Department and analyzed for thickening of the inner table of the frontal calvarium. Analysis was done using statistical package for social sciences (SPSS ) version 13.0
Results: 587 skull CT were studied with age range of 6months to 86 years. Males were predominant with 341 males and 246 females, giving a male to female ratio of 1.39 : 1. 3.41% (n-20) of the studied population had hyperostosis frontalis interna. They were all females with age of onset at 5th decade and peaking at 8th decade of life. 6.25% of female patients aged 50-59 had HFI, 16.67% of females aged 60-69 had HFI, 36.36% of females
aged 70-79 had HFI. While 50.00% of females aged 80-89 years had HFI. 60.00% and 20.00% of cases characterized had type A and B HFI  respectively.
Conclusion: Hyperostosis frontalis interna in Uyo is age and gender related, being restricted to females above 50years of life.