Dizziness/Vertigo

diagnosis

It is important for a doctor to diagnose the cause of vertigo (dizziness) as quickly as possible to rule out serious conditions such as cardiovascular disease, stroke, hemorrhage, or tumor.
In trying to determine the cause of vertigo, a doctor may ask if the dizziness: causes the room to spin or produces a sensation of motion; is associated with a feeling of faintness or lightheadedness; or causes the individual to lose balance.
Physical examination includes measuring blood pressure and heart rate. Neurological examination includes testing facial and vestibular nerves and muscles, strength, coordination, balance, and walking (gait).
The positional vertigo test is used to help distinguish peripheral from central vestibular disorders. In this test, the individual sits on a table with the head turned to the side. The doctor then supports the head and lowers it gently below the table while the individual lies back. The individual reports symptoms of vertigo while the doctor looks for circular movement of the eyes (called nystagmus). A delay between the onset of nystagmus and the sensation of vertigo usually indicates a peripheral vestibular disorder. Lack of a delay may indicate a central vestibular disorder. The test is repeated with the head turned in the opposite direction.
Electronystagmography (ENG): Electronystagmography (ENG) is a neurological test used to evaluate the vestibular system. ENG involves testing hearing in both ears (audiometry tests), testing eye movements, and evaluating responses to changes in posture and position. In a darkened room, recording electrodes are placed near the eyes. Warm and cool water or air is gently introduced into each ear canal. Since the eyes and ears work in coordination through the nervous system, measurement of eye movements can be used to test the balance system. In about 50% of individuals, the balance function is reduced in the affected ear. Rotational testing or balance platform may also be performed to evaluate the balance system.
Blood tests: Blood tests include a complete blood count (CBC) and kidney and thyroid panels to rule out systemic diseases (such as kidney disease or thyroid disorders). If the individual is taking medications (such as aminoglycosides or anticonvulsants), drug levels are obtained.
Imaging tests: Imaging tests may be used to detect brain abnormalities (such as stroke or tumor). A magnetic resonance imaging (MRI) test uses a magnetic field and radio waves to create cross-sectional images of the head and body. A doctor can use these detailed, clear images to identify and diagnose a wide range of conditions that may cause vertigo.

signs and symptoms

Vertigo refers to the sensation of spinning or the perception that surrounding objects are moving or spinning. Some individuals describe a feeling of being pulled toward the floor or toward one side of the room. Moving the head, changing position, and turning while lying down often worsen vertigo.
The sudden onset of vertigo usually indicates a peripheral vestibular disorder (such as benign paroxysmal positional vertigo, Meniere's disease, and vestibular neuritis).
Symptoms of benign paroxysmal positional vertigo (BPPV) usually last a few seconds to a few minutes and come and go. They also may include lightheadedness, imbalance, and nausea, usually as a result of a change in position (such as when rolling over in bed or getting out of bed). Symptoms of Meniere's disease and vestibular neuritis include vertigo, hearing loss, ringing in the ears (tinnitus), and ear pressure that often last hours to days.
Peripheral vestibular disorders also may cause the following symptoms: blurred vision; fatigue and reduced stamina; headache; heart palpitations or arrhythmias (rapid fluttering of the heart); imbalance; inability to concentrate; increased risk for motion sickness; muscle ache (especially of the neck and back); nausea and vomiting; reduced cognitive function (including thinking and memory); sensitivity to bright lights and noise; and increased sweating.
Vertigo caused by a central vestibular disorder usually develops gradually. Central vestibular disorders are usually caused by underlying health conditions, such as stroke or migraine. These central vestibular disorders may cause symptoms including: double vision (diplopia); headache (may be severe); impaired consciousness; inability to speak due to muscle impairment (dysarthria); lack of coordination; nausea and vomiting; and weakness.

complications

Severe vertigo can be disabling and may result in complications such as irritability, loss of self-esteem, depression, negative effects on work performance and quality of life, and injuries from falls. Falls are the leading cause of serious injury in people over the age of 65.
Experiencing dizziness while driving a car or operating heavy machinery can increase the likelihood of an accident.
Dizziness may also lead to nausea and vomiting.

causes and risk factors

Vertigo usually occurs as a result of a disorder in the vestibular system. The vestibular systems are structures of the inner ear, the vestibular nerve, brainstem, and cerebellum that deal with balance. The vestibular system is responsible for integrating sensory stimuli and movement and for keeping objects in visual focus as the body moves. Blurred vision may also lead to dizziness.
When the head moves, signals are transmitted to the labyrinth. The labyrinth is a structure in the inner ear that is made up of three semicircular canals surrounded by fluid. The labyrinth transmits movement information to the vestibular nerve, which then carries the information to the brainstem and cerebellum (areas of the brain that control balance, posture, and motor coordination). There are a number of different causes for dizzy spells.
Central vestibular disorders: Central vestibular disorders that may cause vertigo include cardiovascular disorders, such as bradycardia (heart rate below 90 beats per minute) or tachycardia (rapid heart rate exceeding 100 beats per minute), central nervous system (CNS) disorders including stroke (a lack of oxygen to the brain due to loss of blood flow, resulting in neurological damage), brain hemorrhage (bleeding), and head trauma; migraine (30-50% of migraine patients experience vertigo); joint and muscle conditions, including multiple sclerosis (MS), occurring when muscle loss affects the brainstem or cerebellum. Other causes of vertigo include orthostatic hypotension (a sharp decrease in blood pressure upon rising from a lying or sitting position to a standing position), which is caused by diabetes, dehydration, anemia, and some medications, hypotension in general, and diseases, such as kidney disease, thyroid disorders, and cancer. Tumors can also affect the central vestibular system (acoustic neuroma).
Rapid changes in motion, such as riding on roller coasters, in boats, cars, or even airplanes, may occasionally make individuals experience dizziness. This type of dizziness is called motion sickness.
Peripheral vestibular disorder: There are several types of peripheral vestibular disorders that can occur and cause vertigo (dizziness), including benign paroxysmal positional vertigo or BPPV. BPPV is the most common peripheral disorder and may be accompanied by hearing loss, reduced cognitive function, and facial muscle weakness. Another peripheral vestibular disorder causing vertigo is Cogan's syndrome, which is inflammation of connective tissue in the cornea. The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber, providing most of an eye's optical power. Cogan's syndrome results in vertigo, ringing in the ears (tinnitus), and loss of hearing. Also, Meniere's disease, which is fluctuating pressure of inner ear fluid (endolymph), results in severe vertigo, ringing in the ears (tinnitus), and progressive hearing loss. Ototoxicity, or the loss of hearing due to certain medications (including anticonvulsants and certain antibiotics), and vestibular neuritis, or inflammation of vestibular nerve cells, may also cause vertigo. Vestibular neuritis may be caused by a viral infection.
Medications: Some medications, such as certain diuretics (including furosemide or Lasix®), and aspirin, can cause ototoxicity or loss of hearing that may lead to dizziness. Ototoxicity may result in damage to the inner ear or the 8th cranial nerve (acoustic nerve) and cause vertigo. The damage can be permanent or temporary.
Long-term use or high doses of antibiotics such as aminoglycosides (including streptomycin, gentamicin, and tobramycin), macrolide antibiotics (such as erythromycin), vancomycin, and antineoplastics or chemotherapy drugs (such as cisplatin and carboplatin) can cause permanent ototoxicity.
Other medications that may cause temporary ototoxicity include: anticonvulsants, such as phenytoin (Dilantin®) and carbamazepine (Tegretol®); antidepressants, such as clomipramine (Anafranil®) and amoxapine (Asendin®); antihypertensives, such as labetolol (Trandate® or Normodyne®) and enalapril (Vasotec®); loop diuretics, such as bumetanide (Bumex®) and furosemide (Lasix®); pain relievers, such as aspirin; and quinine (chloroquine, quinidine). Alcohol, even in small amounts, can cause temporary vertigo in some people.
Centrally acting drugs, including pain mediactions such as morphine, and anti-anxiety drugs, such as diazepam (Valium®), may also cause dizziness.
Presyncope: Presyncope is the medical term for feeling faint and lightheaded without losing consciousness. Sometimes nausea, pale skin and a sense of dizziness accompany a feeling of faintness. Causes of presyncope include: a sudden drop in blood pressure (orthostatic hypotension. A dramatic drop in systolic blood pressure (the pressure due to the heart contracting or the higher number in a blood pressure reading) may result in lightheadedness or a feeling of faintness. Presyncope can occur after sitting up or standing too quickly due to orthostatic hypotension; and an inadequate output of blood from the heart (congestive heart failure). Conditions such as partially blocked arteries (atherosclerosis), disease of the heart muscle (cardiomyopathy), abnormal heart rhythm (arrhythmia), or a decrease in blood volume may cause inadequate blood flow from the heart.
Others: A lightheaded feeling can be caused by inner ear disorders, such as otitis media (inner ear infection) and anxiety disorders. Certain anxiety disorders, such as panic attacks and a fear of leaving home or being in large, open spaces (agoraphobia), may cause lightheadedness and hyperventilation. Abnormally rapid breathing that often accompanies psychiatric disorders, such as anxiety, may make an individual feel lightheaded.