What is vertigo?

Vertigo is just a fancy word for a false sense of motion. The perceived motion can be of any of the multiple kinds, like a sense of ground being moved underneath, on-a-boat feeling, head turning, things around are moving, or a frank spinning sensation. It is the feeling we used to enjoy in young age when we turned around and around and then stopped, left with a feeling of moving around and loss of balance. It is not a diagnosis, just a symptom. There are many conditions that can cause vertigo; a common one is called Benign Paroxysmal Positional Vertigo (BPPV). Because of its common nature, many times physicians just use the term vertigo while talking about BPPV. BPPV is a malfunction of vestibular system placed deep inside our ears.

What is the vestibular system?

Vestibular system is a structure deep in our ears. It is complex; it is intriguing, and fascinating, and not completely understood yet. Following is a general introduction. To keep our balance in all kind of postures we assume or activity we perform, our brain always wants to know the direction and the type of movement (e.g., rotation or linear) and, in reference to our body, where our head is. The information from this system helps to maintain balance, especially if our vision is compromised.

A pair of three bony semi-circular canals or tubes is placed, one set on each side, deep inside the ear. These three tubes in a way are aligned with three axes, x, y, and z, acting as sensors. They are filled with jelly like fluid with one end slightly dilated. Close to that are two separate smaller but similar compartments, called utricle and saccule, with similar structural detail. Floor of each dilated area of the canals, utricle and saccule, is lined with thin hair like cells (or hair cells) in erect position. These hair cells can bend in different directions if there is a movement in the fluid. Suspended on top of these cells are tiny calcium carbonate crystals, like a weight. The crystals are bound together by glue like material, which keeps them together.

Every head movement we make is either in x, y, or z-axis, or any of their combinations. Due to their inertia, every movement generates a tiny motion of the crystals suspended in the fluid, which creates a tiny wave in the fluid. The fluid movement creates tiny bend in the underneath hair cells. The mechanical movement of hair cells is converted in an electrical signal that travels to the brain. The receptors in semicircular canals sense movement, especially rotational movement. The utricle and saccule sense vertical and linear movements, which probably also includes gravity. Because of exact replica of three tubes on either side, with opposite orientation, any movement of hair cells on one side is associated with a similar movement on the other, but in opposite direction. The system is placed at about 30-degree angle tilted upwards because in erect body posture our head is tilted forward by about 30 degrees from the earth’s horizontal plane. This way the x-axis of the system stays within earth’s horizontal plane.

It is a beautifully designed engineering marvel operating through multiple scientific principles including solid-state physics, fluid dynamics, electrochemistry, electronics, complicated biochemistry, and even much more that we do not yet understand. It is precise enough to sense every bit of head motion, but modulated enough to not overshoot or undershoot and send just the right signal to the brain. Constantly reading these signals, brain adjusts our posture, muscle tone, and the direction of gaze to let us flawlessly move around, dance, run, jump, or dive.

This system works well if both left and right sides are in sync; any amount of asynchrony sends mixed messages. If a person is stationary and this apparatus sends an asymmetric signal, it is read as a sense of motion, a false sense of motion, which we call vertigo. The type and severity of vertigo depends upon the location and the extent of the problem. There are numerous conditions that may affect this system and cause vertigo.

What is Benign Paroxysmal Positional Vertigo (BPPV)?

BPPV is a common malfunction of the vestibular system. In BPPV some of the crystals in the semicircular canals or tubes get loose. They either float or settle in the lower part of the tube(s), and mess up the system by creating a mismatch of signals going to the brain. This happens when the patient assumes a certain posture, like bending or turning to one side. The posture triggering an episode of vertigo depends upon which tube (out of six – 3 on each side), or the utricle or saccule are affected. Depending upon the severity of asymmetric signal, feeling of false motion or vertigo can be subtle like a slight feeling of being “off balanced,” moderate like on a boat feeling, or a feeling of a fall, or severe resulting in spinning sensation with nausea, blurred vision, and unsteadiness. Brain quickly makes adjustments and a few seconds to a minute or two later, patient feels better. So it is a condition of dizziness that is episodic, it comes and goes, instead of being continuously dizzy for hours to days.

BPPV is called benign because in spite of its scary looking symptoms; it is not a life-threatening illness. It is rather a nuisance. Unlike what a patient may think, it is not a problem of brain. It is paroxysmal because it comes and goes, at times staying for days to weeks before disappearing, and then reappearing another day, usually upon waking up or in the middle of the night. It is positional because a particular position of the body or head seems to trigger it, more commonly bending over, or turning over. The trigger may be as subtle as just raising the head while driving and looking in the back view mirror. It is called vertigo, because it is a false sense of motion. I like to add another “P” and call it BPPPV: by its nature, once it starts, it is also a permanent condition. This is because the cause is a mechanical dysfunction of vestibular system that we are unable to fix.

What causes BPPV?

As described above, it is a malfunction of the vestibular system. Small calcium carbonate crystals come out of their place, and are unable to take back their position. Once separated from the rest, they are always loose. Because of these loose crystal on one side, asymmetrical or unequal signals travel to the brain. Brain perceives asymmetry in vestibular signals as motion. The type of motion depends upon the location of the defect.

Head trauma is a known cause for BPPV, probably by jolting the whole system and letting some crystals loose. In most cases though, there is no history of significant trauma. In young people, trauma is the typical trigger but BPPV typically appears in middle age, from an unknown cause. It is a mechanical problem, not an infection or inflammation.

What are the symptoms of BPPV?

Typical symptoms are a false sense of motion, or spinning sensation, unsteadiness, nausea, blurred vision (because of quick to-and-fro movements of eyes), sometimes vomiting, and rarely a fall. Each episode of dizziness is brief, usually lasting for a few seconds to a minute or two. It may recur again and again. .

Is BPPV a brain problem or a stroke?

No, it is not. It is a problem with internal parts of ear.

How is BPPV diagnosed?

With its typical history and bedside examination. A physician performs a set of head and neck manipulations called Dix-Halpike maneuver, which is very helpful to make the diagnosis. No formal test is required.

How long BPPV may last?

Once it appears, its risk is permanent. This is because of the nature of this problem.

What is the treatment for BPPV?

If confirmed by the Dix-Halpike maneauvre, the physician can perform an Epley maneuver for relief of symptoms. Epley maneuver is a set of head and neck manipulations performed to put the crystals back in their original position, which may provide instant relief.

We have not found a way to permanently put the crystals back in place and glue them again. Even if we try to realign them in their natural position by Epley maneuver, they easily get misplaced again. There is no effective surgical treatment, injection treatment, or even a medicine for it. Usually meclizine is prescribed but it practically has no impact. In fact, the most common side effect of meclizine is dizziness, though of a different nature.

Also Epley maneuver cannot be performed in many patients (e.g., elderly, or with neck arthritis or neck injury), and it does not work in all cases, depending upon the semicircular tube or canal affected. In difficult cases, a referral to a specialized center with expertise on neuro-otology (e.g., Mass Eye and Ear Infirmary in Massachusetts) is appropriate, where testing with more sophisticated machinery may help to reveal the malfunctioning location.

Majority of BPPV can be managed by a simple exercise regimen. Most patients require education about what this condition is and what it is not. They are advised common sense precautions to avoid falling, and guidance to do some home exercises to keep it at bay.

What is home exercise for BPPV?

The principle of any physical therapy or treatment of BPPV is to trigger episodes of dizziness in a controlled environment so that brain may learn and make appropriate adjustments, and so not create significant symptoms. Brain quickly learns, but in this case, also quickly forgets. In more difficult cases, one is advised to perform exercises on daily basis to keep symptoms at bay. It is also important to know that a wrong exercise may easily dislodge or displace more crystals and make the condition even worse.

Sit in a safe and comfortable place. Bend the upper body down until head is touching the knees or as much as possible, straighten up and then bend to one side, as much as possible, and then to the other side as much as possible. Repeat these movements about 10 times, a few times a day. The purpose of this exercise is to trigger vertigo in controlled environment so that brain may get used to getting asymmetric sensory input.

If a patient is inclined, it is not difficult to learn to self-perform Epley maneuver. It can be a useful option in some cases, provided the location of the defective semicircular canal is clearly defined. In recent years, there has been a surge of physical therapy treatment programs for dizziness, the so-called vestibular rehab programs. It is unclear though if an elaborate exercise regimen is more beneficial than a simple regimen performed at home. On the other hand, large number of patients, due to their neck and spine conditions, is unable to safely undertake complicated exercises or manipulations.

What are some other conditions of vestibular system that may cause vertigo?

A: Vestibular neuritis: inflammation or infection in the system.

B: Meniere’s syndrome: High pressure in the system.

C: Drug toxicity: Some drugs may damage hair cells.

D: Vestibular dehiscence syndrome: An abnormal opening in a canal.

What are some brain conditions that may cause vertigo?

Problem with certain areas of brain particularly cause severe vertigo type dizziness. These are the areas involved integrating signals from the vestibular apparatus. Brainstem part of the brain and the cerebellum may cause vertigo, and unsteadiness. Common causes are stroke, multiple sclerosis, infection, trauma, or tumor.

Where can I get more information about BPPV?

American Academy of Neurology
American Academy of Otolaryngology