The cochlea and vestibular receptors have a highly sensitive mechanism of action, exhibit intense metabolic activity and have a limited reserve of stored energy¹. Muscles store energy, but the ears, eyes and brain do not store energy and therefore depend on the blood supply reaching those areas. The stria vascularis relies on oxygen, glucose and other substances to generate endocochlear potentials. A reduction in these potentials initially causes mild hearing loss with good speech discrimination and a flat audiometric profile; very often, it presents a distinctive pattern in which low and high frequencies are most severely affected, and the audiometric assessment shows an inverted “U”-shaped curve.