It is often said that “the eyes are the windows to the soul”, but in fact they are also an important component of balance. The human body has a “vestibulo-ocular reflex”, and the functional state of the vestibular pathway can be indirectly inferred by observing and recording eye movements. Therefore, infrared video nystagmography is the most objective tool for the diagnosis of vertigo disorders. The patient wears a special video eye patch, and the infrared camera is used to record eye movement images directly for real-time recording and quantitative analysis. The general examination includes: (1) Spontaneous nystagmus: Involuntary nystagmus produced by the patient due to pathological stimulation of the vestibular system. (2) Positional nystagmus: Dix-Hallpike evoked test, which is specific for the diagnosis of benign paroxysmal positional vertigo (otolaryngitis). (3) Oculomotor examination: Specific performance of eye movements observed when the patient’s eye moves with an object and analyzed. (4) Vestibular double-temperature: Injecting hot and cold air or water into the right and left ear canals respectively to produce movement of the endolymphatic fluid in the stimulated ear (vestibular hemifascia) and subsequently trigger the vestibular response of vertigo sensation, and judge the function of the vestibular hemifascia on the right and left sides respectively.