diease

Dizziness


Dizziness overview and Definition

Dizziness is the feeling of being lightheaded or unbalanced. It mainly affects the sensory organs specifically the eyes, ears and might result in fainting. Dizziness isn’t a disease, but it a collection of various disorder.

Vertigo and disequilibrium may cause a feeling of dizziness but the vertigo is different from dizziness because vertigo might result in spinning like effect.

True dizziness is the feeling of lightheadness or nearly fainting.


Epidemiology

The overall incidence of dizziness, vertigo, and imbalance is 5-10%, and it reaches 40% in patients older than 40 years. The incidence of falling is 25% in subjects older than 65 years. 


Pathophysiology

Vertigo:

The vestibular system is responsible for the sensation of motion, both in linear and angular directions. The semicircular canals and otoliths are responsible for this process. Vertigo is a deficit in either the sensation of motion (i.e. an issue with the semicircular canals) or a centralized issue with the processing of information from the semicircular canals.

Inner ear disorders frequently causes the feeling of dizzy. The most common cause include benign paraoxysmal positional vertigo (BPPV), Meniere’s syndrome and ear infections.

 

Benign paroxysmal positional vertigo (BPPV):

Being paraoxysmal positional vertigo makes the person dizzy when he/she changes the head or body position( like over bending). It usually only lasts foe a few seconds to minutea. This harmless condition happens when calcium crystals in the inner ear moves out of place. The benign paraoysmal vertigo might happens due to head injury or simply from getting older. The physician can lead you through a series of simple moves, called canalith repositioning procedure(CRP). These results in backward movement of crystals back to their proper positions.

 

Meniere’s syndrome:

Meniere’s syndrome involves having too much of fluid in the inner ear. It is most common among older age group of 40 to 60 years of age. If one experiences Meniere’s syndrome they might also experience the following:

Hearing loss

Muffled or distorted hearing

Nausea and vomiting

Tinnitus ( ringing in the ear)

It usually happens suddenly. They can last from 20-24 hours. Treatment is mainly with anti nausea and anti vertigo medications. The following might also provides a better relief:

Following low salt diet

Limiting the use of alcohol and caffeine

Altering the medications

Quitting smoking

Ear infections:

Viral or bacterial ear infections can cause inflammation (irritation) in the inner ear. The inflammation interferes with the messages your inner ear sends to your brain.

A nerve in the inner ear, the vestibulocochlear nerve, has two branches. Each branch communicates with the brain:

The vestibular nerve sends signals about balance. When the vestibular nerve is inflamed, it might result in the development of vestibular neuritis.

The cochlear nerve sends signals about hearing. If inflammation also affects the cochlear nerve, you develop labyrinthitis. Labyrinthitis also causes ringing in the ears and hearing loss.

Ear infection treatments include medications to relieve the symptoms of nausea and dizziness. You might also need antibiotics, antiviral drugs or  steroids.

The following are the other conditions which might result in the lightheadiness or dizziness.

Within the heart and vascular system conditions that cause dizziness include:

Irregular heartbeat ( Atrial fibrillation)

Low blood pressure(hypotension)

Narrowed arteries(atherosclerosis)

Brain conditions that might result in dizziness. It includes:

Head injury or traumatic brain injury(TBI)

Migraine

Multiple scelerosis

Additional conditions that cause dizziness includes the following:

Alcohol use

Anxiety and stress ( if the person hyperventilate or breathe too quickly)

Carbon monoxide poisoning

Low blood sugar that is hyoglycemia

Medications


Clinical signs & symptoms

Blurred vision 

feeling giddy

fatigue

nausea

unbalanced


Differential Diagnosis

Diagnosis:

Electrocardiogram:

This test records the electrical signals your heart produces. It can detect irregular heart rhythms and other cardiac problems. You may need to wear a portable monitor for at least a day or as long as a month.

Echocardiogram:

 This test uses ultrasound imaging to view the heart and look for conditions, such as valve problems, that can cause fainting.

Exercise stress test:

This test studies heart rhythms during exercise. It's usually conducted while you walk or jog on a treadmill.

Blood tests:

Your doctor may look for conditions, such as anemia, that can cause or contribute to fainting spells.

Tilt table test:

 If no heart problems appear to cause your fainting, your doctor may suggest that you undergo a tilt table test. During the test, you lie flat on your back on a table that changes positions, tilting you upward at various angles. A technician monitors your heart rhythms and blood pressure during the test to see if changing your posture affects them.

Hearing tests:

An audiologist conducts a variety of hearing tests which is also known as audiometric tests to gather information about the ear, the physician assess whether there is a problem with the nerve that connects the inner ear to the brain and see whether the dysfunction affects both the ears.

In otoacoustic emissions testing, a sensitive probe that produces a combination of sounds is introduced into the ear canal. If the inner ear is functioning properly, small hair cells in the ear—tiny sensory receptors that detect vibrations and convert them to electrical signals for the brain to interpret—send back an echo when stimulated by sound. The probe can detect these echo and indicate how well the inner ear is functioning.

   Videonystagmography testing:

       It is used to check the function of the inner ear using a series of visual and sensory test. The inner ear constantly sends signals to the eye muscles to help the head and body to maintain the balance. The audiologist analyses the eye movements dadta and looks for patterns indicating an inner ear disorder.

Rotational chair testing:

The audiologist use the test to check whether the vertigo is of peripheral or central origin. In this also the audiologist analyses the eye movements and they relate it to the health of the inner ear.

Imaging tests

CT scan, MRI scan SPECTs and  PET scans help doctors locate the areas in brain to check for the abnormalities.

Neurological exam

During a neurological exam, your doctor will look for changes in your balance, coordination, mental status, hearing, vision and reflexes. These changes can point to the part of your brain that may be affected by a tumor.

Spinal tap:

A doctor uses a small needle to remove fluid from around the spine. A laboratory examines this fluid to look for cancer cells.


Prognosis

If left untreated the dizziness due to simple causes might get relieved soon. If not then the triggering factor should be excluded


Prevention

Drink plenty of fluids

Monitor the blood pressure

Check the blood glucose level

Take rest and follow good sleep

Maintain healthy diet

Follow stress free life