What is Vertigo?

Vertigo is the illusion of rotary movement. It is the sensation that your body is turning or your surroundings are turning while you remain still. Many of us have experienced vertigo as children on the merry-go-round.

Other symptoms associated with vertigo include:

• nausea, vomiting, ‘sea sickness’
• difficulty concentrating
• difficulty reading
• loss of short term memory
• poor balance, clumsiness
• disorientation
• sensitivity to bright lights and noise
• inability/difficulty driving
• poor tolerance of crowds

What causes Vertigo?

There are many causes of vertigo. The primary cause is a problem with the vestibular organ of the inner ear (see figure 1.1). This part of your balance system provides your brain with information about the position and movement of your head in space. The vestibular organ is critical for balance and the ability to keep your eyes on objects while you or the objects are moving.

Examples of Vestibular Disorders are:

• Benign Positional Vertigo (most common)
• Meniere’s Disease
• Perilymph Fistula
• Endolymphatic Hydrops
• Labyrinthitis (viral or bacterial)
• Acoustic Neuroma

Normal Vestibular Function

Under normal conditions, calcium carbonate crystals are situated in a part of the inner ear called the utricle (see figure 1.2). They are held together there in a gelatinous mass. As your head moves around, this gelatinous mass changes position. It thus bends small sensory nerves, which in turn tell your brain what position your head is in.

The other important part of the vestibular organ is the fluid filled semi-circular canals (see figures 1.1 and 1.2). The canals are positioned in such a way that, when your head moves in space, the fluid in the canals will move in the opposite direction, bending another group of small sensory nerves. These nerves are very sensitive and can feel the direction and speed that the head is moving.

What can go wrong?

When the vestibular organ is injured by trauma, damaged by infection or degenerated because of advancing age, some of the crystals can become disengaged from their gelatinous mass in the utricle. These crystals then float around the inner ear and often find their way into the posterior semi-circular canal. They tend to stay in this canal unless the body assumes certain positions that cause them to float out under the force of gravity.

Benign Positional Vertigo or BPV

When these crystals are present in the canal they interfere with its normal function. They send confusing messages to the nerve endings. This results in Benign Positional Vertigo or BPV. The individual feels this as a "wave of vertigo", often accompanied by nystagmus (involuntary back and forth motion of the eyes). Lying down, getting up or turning over in bed are common ‘problem’ motions. People with BPV often feel dizzy and unsteady when they tip their heads back to look up. BPV may be present for a few weeks, resolve, and then return again.

Treatment

BPV is probably the most common and easily treated form of vertigo.The most effective treatment for BPV is a procedure called the Epley Manoeuvre (also called the Otolith Repositioning Procedure).This procedure is usually performed by a specially trained physiotherapist.

The Epley Manoeuvre entails moving the patient quickly from one position to the other in a specific direction. This allows the crystals in the posterior canal to drain out of the canal into the vestibule, which resolves the problem instantly. The procedure takes about 15 minutes. This treatment is effective 80% of the time. Sometimes more than one treatment is necessary.

If the response to this manoeuvre is poor or no response occurs, further evaluation may be indicated. Another effective but more time consuming technique, the Brandt-Daroff Exercise (see figure 1.3), consists of lying down on your side then getting up quickly. This exercise can be taught by the physiotherapist.

Brandt-Daroff Exercise

Clinical Associate for Vertigo Rehabilitation:

Marguerite Daubney   Hons.B.Sc., B.Sc.(P.T.), M.Sc.(Rehab)

• practicing as a Registered Physiotherapist since 1989
• special training in Benign Postural Vertigo

Information courtesy of:

Vestibular Disorders Association
Andre Riopel, R.P.T.