episodic vertigo
Introduction
Introduction It is a common mechanical condition of the inner ear, accounting for about 20% of all vertigo, and is also the cause of about half of otogenic vertigo. Although the disease is an ear disease, it is often diagnosed in the first diagnosis of neurology, and many misdiagnosed as vertebrobasilar insufficiency, cervical vertigo and delayed treatment. Dizziness is a general term for dizziness and dizziness. It is glare with vertigo, unclear vision and darkness and darkness. It can be rotated by the object, or can not stand as a halo.
Cause
Cause
Early research suggests that it is a cap stone or a stone. The theory speculates that otoliths on the sac capsular sac are detached due to infection, trauma, or degeneration, and are deposited in horizontal semicircular canals due to anatomical location. The change in head position (lower or head-up) places the horizontal semicircular canal in a horizontal position, which causes the otolith fragments to move in the tube by gravity. Because it is more specific than the inner labyrinth, it produces a "plugging effect", which causes the ampulla of the ampulla to shift, stimulating the vestibular nerve and causing dizziness.
This theory can explain various clinical features well: the otolith fragments have inertia before the incubation period; shortly after the head position changes, the otolith fragments stop moving, the vertigo is transient; the head position returns to the original position, the otolith fragments again Moving in the opposite direction produces another dizziness; after multiple movements, the plugging effect weakens and fatigue occurs. However, most patients have no clear cause, 17% have a history of head trauma before onset, 15% have a history of vestibular neuronitis (which can occur within 2 to 8 years after inflammation), and a few have a history of vertebrobasilar insufficiency. . It is still believed that tube stone disease is the main cause.
Examine
an examination
Mainly have the following symptoms:
(1) Incubation period: Dizziness occurs 1 to 4 seconds after the head position changes.
(2) Rotation: Dizziness has a distinct sense of rotation, and the patient has a sense of rotation when he or she rotates or closes the eye.
(3) Transient: Dizziness stops itself in less than 1 minute.
(4) Conversion: The head returns to the original position to induce dizziness again.
(5) Fatigue: After repeated head position changes, the symptoms of vertigo gradually decrease. The patient's performance met these five characteristics.
The diagnosis is based entirely on typical clinical findings and positive results from the Dix-Hallpike test.
Dix-Hallpike test:
The patient sat on the examination table and quickly took the supine position with the help of the examiner, and was 45 degrees to one side. PC-BPPV, when the head turned to the affected side, a brief dizziness and vertical rotatory nystagmus occurred after a few seconds of incubation. Repeated testing is fatigue.
In addition, there is a supine lateral head test. The patient sits on the examination table and quickly takes the supine position. Then the head turns 90 degrees to one side. HC-BPPV immediately shows severe vertigo and horizontal nystagmus.
Because the above test can induce vertigo, the patient will fear, shout or not cooperate, so the purpose should be clearly explained before the examination, to achieve cooperation, to ensure that the eyes are not closed. For patients with severe heart disease, cervical spondylosis, and carotid stenosis, use or disable it. Because of the good prognosis of BPPV, various neurological and otological examinations are normal, so all patients with vertigo should be tested Dix-Hallpike, and those who are positive can be diagnosed immediately to avoid unnecessary examination and invalid "symptomatic treatment".
Commonly misdiagnosed diseases include cervical vertigo, vertebrobasilar insufficiency, non-specific dizziness, cardiogenic dizziness, and neurosis.
Diagnosis
Differential diagnosis
1. Cervical vertigo: also known as vertebral artery compression syndrome. The cause may include cervical degeneration, cervical and neck soft tissue lesions, neck tumors and skull base deformities, etc., causing vertebral artery compression and ischemia leading to vertigo; vertebral artery itself such as atherosclerotic stenosis and deformity More susceptible to the disease. The cervical sympathetic plexus is directly or indirectly stimulated, causing vertebral artery spasm or reflex inner ear circulatory disorder. Abnormal reflection can also be caused, such as the cervical occipital receptor in the ring pillow joint and the upper three cervical vertebrae capsules are subjected to various stimuli, and the impulse can be transmitted to the cerebellum or vestibular nucleus to produce dizziness and balance disorders. The main clinical manifestations are various forms of vertigo, which are obviously related to sudden head rotation, often accompanied by nausea, vomiting, ataxia, etc. Sometimes there may be black sputum, diplopia, amblyopia, etc., and the symptoms last for a short time. The treatment can be used for neck traction, physiotherapy, massage, etc.; appropriate application of vasodilator drugs, microcirculation drugs and vitamins.
2. Vertebral-basal artery insufficiency: The vertebral-basal artery has three important features in anatomy and pathology: one is that the vertebral artery diameters on both sides are 2/3 in normal people, and even unilateral vertebrae The arteries are small or absent; the second is that the vertebral artery passes through the 6th to 1st cervical vertebrae and enters the skull through the occipital foramen, that is, walking in a bone tunnel with great mobility. After the age of 50, the cervical spine is prone to degeneration. And the formation of osteophytes, such as low blood pressure is more likely to promote blood supply insufficiency; Third, the vertebral artery is prone to atherosclerosis, with the age, the arterial lumen gradually narrowed, blood flow decreased. The main clinical manifestations are acute dizziness, often the first symptom; accompanied by nausea, vomiting, balance disorders, unstable standing and weakness of both lower limbs.
