Vertigo

Introduction

Vertigo is the sensation of spinning or false movement.  It can result from trauma, infection, or diseases that affect the inner ear.  Vertigo is usually a harmless condition but a doctor should evaluate it.  Vertigo may be treated with medications, surgery, or rehabilitation therapy.

Anatomy

Balance is a complex function.  Balance requires the ability to produce movements and interpret information about your body’s position in space.  Balance requires the coordination of your visual, somatosensory, and vestibular systems.

Your visual system provides information about your environment and allows you to maintain your gaze no matter how you move your head.  Your somatosensory system consists of proprioceptive nerve endings throughout your body, which provide your brain with information about the location of your body in your environment.  The vestibular system in your inner ear sends signals to your brain about the position of your head.  Coordinated muscle movements continually move your body and keep it in an upright position.  If any of the systems are disrupted, the illusion of movement, balance problems, and dizziness can occur.

The vestibular system is needed for balance and position sense.  The vestibular system consists of the semicircular canals and the otoliths.  The semicircular canals are three small loops that are filled with liquid and tiny hairs.  The liquid in the semicircular canals moves whenever you move your head.  In turn, the liquid moves the tiny hairs.  The hairs have position sensors that send messages to your brain about the position of your head.  Your brain processes the message and sends signals to your muscles so that you keep your balance.

The otolith structures in your inner ear are called the saccule and utricle.  They contain tiny hairs and otoconia crystals that float in gel.  When you move your head, the otoconia crystals move inside of the gel and put pressure on the hair cells.  When the hair cells move, they send messages to your brain.  The utricles mainly send messages to signal eye movements, so that you can maintain your gaze.  The saccules primarily send messages about the position of your head.  Your brain processes the information and sends signals to your muscles to keep your body in an upright position.

Causes

Vertigo is the false sensation that you or your environment is spinning, when in actuality it is not.  For example, vertigo can make it seem like a room is spinning or moving.  Injuries or medical conditions can affect the vestibular system in the inner ear, change the way nerve signals travel, or change the way nerve signals are processed in the brain.  Additionally, trauma and neurological disorders can interfere with visual processing. 

You may experience vertigo because of one or more contributing factors.  Benign paroxysmal positional vertigo (BPPV), labyrinthitis, and vestibular neuritis most frequently cause vertigo.  Vertigo can result from multiple sclerosis, traumatic brain injury, Ménière's disease, and acoustic neuromas.

BPPV occurs when the otoconia break off and float freely in the ear canal or enter the semicircular canals.  The otoconia may break free during a whiplash or head injury.  Because the otoconia are free floating, they send confusing messages to the brain about the body’s position.  The mixed messages result in vertigo.

Vestibular neuritis is caused by a viral infection that affects the vestibular nerve and disrupts the nerve signals.  Labyrinthitis can result after an ear infection, allergy attack, or an upper respiratory infection.  It causes parts of the inner ear to become irritated and swollen.  The inflammation in the inner ear interferes with balance functions and can cause hearing loss.

Symptoms

Diagnosis

Treatment

Am I at Risk

You may be at risk for vertigo if you have experienced head trauma or whiplash.  Your risk may increase if you develop medical conditions that are associated with vertigo.

Complications

Advancements

Surgical options are available for severe cases of vertigo that do not respond to repositioning manuvers.  Posterior ampullary nerve transsection and posterior semicircular canal occlusion are the 2 specific techniques used in intractable BPPV surgery.