Organ Histopathological Associations With Hyperostosis Frontalis Interna In Humans

An increased thickening of the frontal bone by irregular laminar additions on the inner surface just deep to the dura mater have been known in the archaeological and medical record as hyperostosis frontalis intema (HFI). The distribution of this is idiosyncratically restricted to the frontal and has no known etiology. The prevalence among post-menopausal females and rarity in males suggests that it is hormonally driven. Here we report histopathological findings of particularly hormonally active organs (pituitaries, gonads and liver) from a geriatric cadaveric sample in which HFI is assessed. BD was present in 50 % of males (7/14) and 95 % (21/22) of females. All males with HFI had testicular atrophy or had testes absent. Males with HFI category C or D had moderate to severe testicular atrophy. Decreased numbers of interstitial cells (Leydig cells) were present in 83.3 % of males with HFI. All but one female (21/22) from this study exhibited evidence of HFI, and ovarian pathologies were unevenly distributed (fibromas in two) and most exhibited signs of being healthy and post-menopausal. Liver pathologies had opposite patterns between the sexes, with more liver pathologies occurring among males without HFI (particularly passive congestion and bile stasis). The only exceptions were that the one case of liver neoplasia was found in a male with HFI and steotosis was found in two cases with HFI and one case without HFI. In females all cases of liver pathologies (steotosis, hepatitis, passive congestion, fibrosis, and bile stasis) were associated with HFI. It appears that gonadal pathology is most closely associated with HFI in males but not females, suggesting that the role of estradiol in this unusual growth of bone in geriatric humans may be worth investigating further.