Benign paroxysmal positional vertigo (BPPV) is a transient paroxysmal attack of vertigo and nystagmus that occurs when the head moves rapidly to a specific head position, and it is called varicose vertigo because the signs appear during head movement. Barany (1921) first reported this disease, and Dix and Hallpike established the Dix-Hallpike dislocation test, and Schuknecht suggested that the symptoms of this disease originated from the abnormal function of the posterior semicircular canal jugular crest. This disease is one of the common disorders of peripheral vertigo. Its incidence ranks first among peripheral vestibular disorders. It is thought to account for 20-40% of peripheral vestibular disorders. It is more common in women than in men and can be familial. It occurs mostly in the posterior semicircular canal, followed by the external semicircular canal, and occurs least in the anterior semicircular canal. Etiology: Various causes lead to otolith dislodgement into the semicircular canal. The etiology of about half of the patients is still unclear, and the causes are mainly divided into the following two categories. 1. Idiopathic: about 34-68%; 2. Secondary: mostly seen in vestibular neuritis, Meniere’s disease, sudden deafness, viral labyrinthitis, internal auditory artery ischemia, migraine, head trauma, post-operative middle and inner ear surgery, post-cochlear implantation, ototoxic drug damage, otosclerosis, inner ear malformation, chronic middle ear mastoiditis, and cervical vertigo. Clinical manifestations: 1. Symptoms: The onset of symptoms is sudden and often related to a certain head position or postural activity. The symptoms of vertigo appear when the head position (the affected ear is downward) is stimulated, and nystagmus occurs within 3-10s after the change of head position, while vertigo often lasts within 60s, and may be accompanied by nausea and vomiting. The symptoms often occur when lying down in a sitting position, or when moving from a lying to a sitting position, or when turning over in bed. The duration of the disease may last from a few hours to a few days, but may last for months or years. (2) Examination: (1) Dix-Hallpike dislocation nystagmus test is an important routine test for posterior semicircular canal BPPV (2) Sinusoidal rotation test is used to examine patients with BPVV in the external semicircular canal. The patient is seated, head is tilted forward 30o, rotation speed is 0.04Hz~0.5Hz, recorded with ENG closed eyes, positive eye velocity at low frequency is phase shift reduction. (3) Audiological examination Generally, there is no abnormal change in audiology, but hemianopsia can be accompanied by abnormal hearing in the affected ear if it is secondary to some ear disease. (4) Other Posturographic examinations may show abnormalities, but they are not characteristic. Vestibular function tests, neurological examinations, and CT or MRI examinations are used for differential or etiologic diagnosis. Treatment: Although BPPV is a disease with a tendency of self-healing, it can sometimes take months or years to heal spontaneously, and in serious cases, it can lead to loss of working ability, so treatment should be carried out as much as possible. 1.Anti-vertigo drugs Guilizine (brain yizine) or flunarizine, isoprostanes (fenagan), etc. have certain effect. 2.Otolithic repositioning method, with remarkable efficacy, is the main treatment method used in the clinical treatment of this disease. 3.Other vestibular rehabilitation therapy training. 4.Surgical therapy If the above therapies are ineffective and affect the quality of life and work, posterior potbelly neurectomy or hemianoplasty for obstruction is feasible.