Skeletal vasculature, mainly consisting of external carotid artery branches, plays an important role in these ossifications and bone remodeling 3. Bone remodeling is an important process for bone development and calcium homeostasis, and persists even after skeletal maturity 2. The neurocranium mainly develops via intramembranous ossification, but ethmoid bone and portions of the occipital, temporal, and sphenoid bones develop via endochondral ossification. The skull is formed both by intramembranous and endochondral ossification. ![]() Although mechanical and metabolic stimulation in childhood can effect structural changes in the skull, it commonly does not change in size and form after the head circumstance reaches a plateau. Head circumference continues to increase several years after the brain volume reaches a plateau, due to changes in skull thickness, reaching an adult morphological plateau at around 20 years age. Aberrant growth of cranial volume occurs in first 2 years of age, and the cranial volume at 9 years of age reaches 95% of that of the adult brain 1. The growth rate of the head’s circumference is related to cranial volume. These uncommon skull shapes are useful CT findings in screening subjects for early evidence of mental diseases and intracranial ischemic diseases with arterial stenosis. Plagiocephaly was significantly frequent in moyamoya disease. The skull thickening was especially noticeable in the frontal bone in moyamoya disease. Cases of moyamoya disease, cervical internal carotid artery stenosis, and mental diseases showed significantly thicker frontal and occipital bone than those of control subjects. Head shape had a brachiocephalic tendency with occipital flattening in people born from the 1950s onwards. The findings from head injuries were used not only for control subjects, but also for the analysis of generational changes in skull shape based on birth year. We retrospectively reviewed computed tomography (CT) findings obtained from 365 cases that were treated for head injuries, moyamoya disease, cervical internal carotid artery stenosis, and mental diseases, and investigated the morphological changes in the skull associated with these diseases. On the other hand, few studies have focused on clinical conditions relevant for adult skull deformity. Morphological changes in the child skull due to mechanical and metabolic stimulation and synostosis of the suture are well known.
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