MTHFR and cyclic hematopoiesis: Therefore, in our case, the presence of several of these risk factors (the post-traumatic petrous apex fracture, MTHFR C677T homozygosis and repeated mechanical stress during sports activity), the coexistence of CH and ICAD with overlapping clinical features and the inferable involvement of the same afore-mentioned anatomical structures, suggest that the two diseases could share a common “pathophysiologic focus”: probably hidden vessel wall damage.