Vertigo (dizziness) is a sensation of spatial disorientation. Patients may experience a loss of balance or feel that the room is spinning. The term may also be used to describe any number of similar sensations, including feeling lightheaded, unsteady or woozy. In addition to dizziness, patients may also experience other symptoms such as confusion, nausea, fainting, sweating, headache, vision loss or blurred vision and fatigue.
Dizziness is related to the body's sense of balance, also known as equilibrium. Maintaining balance requires communication and a series of complex processes between the central nervous system (the brain and spinal cord) and the senses. The sensory systems involved in balance include:
Vestibular system. This system of the inner ear monitors movement and direction. It is comprised of three fluid-filled canals that are connected to sacs called the saccule and the utricle. The vestibular system is able to sense both the direction and the speed of the body's movement.
Visual system. The eyes are able to monitor the body's motion and position in space. They add to the information provided by the vestibular system and the proprioceptive system.
Proprioceptive system. The nerves in the skin, muscles, ligaments and joints provide continual information on the position and movement of parts of the body. They are able to sense the feeling of walking, for example, or the physical sensation of traveling fast.
Each of these systems is important in maintaining balance, but only two are required to function at one time. The systems send information on the body's movement and position in space through neurons (nerve cells) to the brain and spinal cord. Inside the brain, the cerebellum, cerebral cortex, brain stem and several other brain regions are involved in processing and producing a response to the signals. Dizziness may result when the brain is unable to process the signals from the sensory systems or the sensory systems send contradictory information to the brain.
In general, there are four disorders that may be characterized as dizziness. These include:
Vertigo. The patient experiences the sensation of falling, spinning, or abnormal movement of the surrounding environment.
Disequilibrium. A sense of imbalance that may occur while standing or walking.
Presyncope. A near-fainting sensation. It may be preceded by ringing in the ears (tinnitus) or diminished vision.
Nonspecific dizziness. Vague sensations of lightheadedness or wooziness that cannot be identified as vertigo, disequilibrium or presyncope.
Potential causes of Vertigo
Dizziness is a result of miscommunication between sensory tissues and the brain. This miscommunication can have a wide variety of potential causes, many of which are temporary and minor. However, in some cases, vertigo may be a sign of a more severe condition that may require medical attention.
One of the most common causes of vertigo relates to problems of the ear. Any disruption of the vestibular system of the inner ear may result in brief or prolonged bouts of dizziness. This may be caused by many factors including inner-ear infections or injuries to the ear. People with hearing loss or tinnitus tend to experience dizziness, which may or may not be related to a more serious underlying condition.
Another common cause of dizziness is conflicting messages from the sensory tissues to the brain. For example, some people may experience dizziness while traveling in a car (known as motion sickness). This is because the eyes sense that the body is moving very fast, whereas the inner ear registers that the body itself is not moving at all. Some older people may also experience this type of dizziness while walking. This may be due to poor vision or a decreased sense of position because of neuropathy. In these cases, the brain does not receive all the sensory signals it is expecting and dizziness may result.
Anything that affects the brain, particularly the parts of the brain involved in movement or balance may also lead to dizziness. For example, one of the first symptoms of a stroke or a transient ischemic attack (TIA) is dizziness as the parts of the brain that are associated with movement and balance are deprived of oxygen and unable to work efficiently. Additionally, dizziness may be caused by factors such as head injuries, seizures and brain tumors or lesions.
There are also several diseases and conditions that may cause vertigo.
Brief, isolated dizzy spells may occur without being cause for alarm. They may be due to pregnancy, standing too quickly, consuming stimulants (e.g., caffeine, nicotine), taking certain medications or wearing new prescription eyeglasses. In these cases, sitting or lying down may help the dizziness pass. Repeated or long-lasting spells of dizziness may indicate a more serious condition, in which case, the patient should consult a physician.
How is Vertigo treated?
Individuals who experience dizziness are generally advised to sit or lie down immediately and wait for the sensation to pass. They should avoid the use of caffeine, alcohol and tobacco, which can worsen symptoms, and refrain from operating motor vehicles and other heavy machinery. Most spells of vertigo are temporary and normally resolve themselves within a short space of time.
A physician should be contacted immediately if any of the following occur:
The person loses consciousness.
Vision, hearing or speech are impaired or lost.
The patient experiences chest pain or tingling, numbness or weakness in a limb.
The room appears to spin.
Dizziness interferes with daily activities.
Lightheadedness lasts for more than a few days.
Dizziness occurs after taking a specific medication (e.g., aminoglycoside antibiotics which can damage the hair cells in the inner ear).
How is it diagnosed?
Diagnosing vertigo begins with a medical provider taking a medical history and performing a physical examination and a neurological examination. The physician will examine the patient's eyes, ears and reflexes. Vital statistics, including pulse rate, blood pressure and temperature will also be taken. To pinpoint the exact nature of the dizziness, the physician may request further information about the patient's symptoms.
Questions may include:
When did the dizziness begin?
How often does the dizziness occur?
Is the dizziness accompanied by other symptoms, such as fainting, nausea or vomiting?
Does the patient feel as though the room is spinning?
Is the dizziness interfering with activities?
Based on the patient's responses to these questions and the results of the physical and neurological examinations, the physician may recommend additional tests.
These may include:
Imaging tests. Cranial computed tomography (CAT scans) and magnetic resonance imaging (MRI) create images of the patient's brain for the physician to examine. They may identify a brain tumor, stroke or other possible neurological cause of dizziness.
Electronystagmogram and hearing tests. These detect abnormal movements of the eyes or damage to the inner ear, both of which affect balance and may cause dizziness.
Blood test or urine test. Analysis of body fluids may identify abnormal levels of blood sugar (glucose) or proteins. This may indicate an underlying condition that may cause dizziness.
Once the underlying cause of the dizziness is diagnosed, treatment for the condition may begin as soon as possible. Many treatments may be available and the patient's physician will recommend the most suitable depending on the cause. Options include taking or discontinuing medications, lifestyle modification (e.g., stopping smoking, exercising), or a medical procedure or surgery.
It is important to follow all of the physician's recommendations for treating dizziness, including proper use of medications and lifestyle changes. Controlling the underlying condition will likely reduce or prevent the occurrence of further dizzy spells.
What might complicate it?
Complications would depend on the underlying disease responsible for the vertigo.
Acute vertigo is usually self-limited. Very little specific treatment is available for individuals with chronic vertigo. In many, change in lifestyle becomes necessary. This is particularly true in individuals with positional vertigo who must learn to avoid the position that precipitates the symptoms.
Other possibilities include acute cerebellar lesions, cerebellopontine angle lesions, partial seizures, brain stem ischemia or infarction, perilymphatic fistula, vertebral basilar artery insufficiency, irritation of destruction of the eighth nerve pathways, tumor, or multiple sclerosis. Vertigo is a symptom that may be present in association with many other conditions.
Neurologist, neurosurgeon, otolaryngologist, ophthalmologist, and internist.