What causes vertigo at organ level?
At organ level, vertigo is a problem of abnormal motion sensation. Vertigo is always caused by one of the two things: Motion sensor Motion analyzer
Your body has two intricately designed motion sensors, one inside each ear. Each motion sensor is made up of three semicircular tubes and two bags. Medically, each motion sensor is known as a vestibular labyrinth.
The three semicircular tubes placed strategically in three different planes at three different angles detect angular motion. They are like pipe levels. When you move your head in any angular direction, the tubes detect that motion and send the signal to your brain.
The two bags below the semicircular canals are called the utricle and the saccule. The utricle is larger tube and it detects linear motion and head tilt in the vertical plane. The saccule is the smaller bag and detects linear motion and head tilt in the horizontal plane.
Vertigo is simply an abnormal motion sensation. You may feel motion that does not exist or your feeling of motion could be exaggerated or distorted. Some people perceive that as room spinning while others perceive it as head spinning or room tilting or losing balance. The vestibular labyrinth sends the signal to your brain for analysis. The nerve that connects your motion sensor with your motion analyzer in your brain is called the vestibular nerve.
Your vertigo symptoms may be caused by problems in your motion sensor or it could be caused by problem in your brain. Vertigo caused by problems in your motion sensor is called peripheral vertigo. Vertigo caused by problems inside your brain is called central vertigo.
What causes vertigo related to motion sensor?
Vertigo caused by your motion sensor is called peripheral vertigo. As you have just learned, your motion censors include semicircular canals, the utricle and the saccule. More than 80% of vertigo is caused by abnormalities in the motion censors. Here are some common conditions that cause vertigo related to motion sensor
Benign paroxysmal positional vertigo (BPPV)
It is one of the most commonly recognized types of vertigo. This type of vertigo is caused by presence of debris or small stones in the back part of your semicircular canals. When you move your head, the small stones move and may create turbulence. This movement results in inappropriate or exaggerated sensation of motion. It improves as soon as the stones settle down. You only feel vertigo when you move your head fast enough to make the stones move. Your vertigo caused by BPPV only lasts for few seconds at a time. However, your symptoms may continue for a long time as long as the stones exist. The treatment for this kind of vertigo includes special maneuver that you can do at home. This maneuver is called Epley maneuver. I will be writing a separate article on it and I will post the link here once it is done.
Vertigo from Meniere disease is caused by the presence of too much fluid inside the motion sensor. The increased pressure caused by excess fluid can damage the delicate membranes and it can throw the motion sensor off balance. You may have episodes of vertigo that usually last longer than that caused by BPPV. They may last anywhere from twenty minutes to a whole day at a time. Because of the prolonged vertigo, you usually have nausea. You may also vomit. In addition to vertigo, Meniere disease will also cause problems with your hearing. It may also make you feel a constant low pitch ringing sensation in your ears. This kind of ringing sensation is called tinnitus.
When you have hearing loss, tinnitus and long episodic vertigo with nausea and vomiting, you can be fairly certain that Meniere disease is what’s causing your vertigo.
Vertigo caused by the inflammation of nerve coming out of the motion censor is called vestibular neuritis. It simply means inflammation of this particular nerve. It is usually caused by virus but sometimes happens without any obvious reason. Unlike BPPV and Meniere disease, vertigo caused by nerve inflammation is persistent and may last for several days. It usually starts abruptly. It may make you feel imbalanced. You may also have nausea and vomiting.
Inner ear injury
Vertigo caused by inner ear injury happens after head trauma. If you have been involved in head trauma affecting your temporal region, you may have had inner ear injury. Vertigo may be caused by direct blow to your motion sensor in your inner ear or it may be caused by indirect trauma related to rapid blow to your head. You may have bleeding in your ear. You may also have trouble hearing after such a trauma.
Depending on the severity of trauma, vertigo caused by inner ear injury may last weeks to months. It is also associated with nausea, vomiting and sense of imbalance.
Thinning and opening of the bone surrounding the semicircular canal may cause vertigo. This type of vertigo is evoked by loud noise, sneezing, coughing or straining. The opening of the bone allows the pressure from the middle ear to be transmitted to the inner ear where the motion sensor is located. Anything that increases ear pressure results in increased pressure in the motion sensor causing abnormal sensation of motion, which is vertigo.
Vertigo caused by this type of bone opening is medically called Semicircular canal dehiscence syndrome.
What causes vertigo related to motion analyzer?
Vertigo caused by problems in your motion analyzer is called central vertigo. When you have vertigo caused by central causes, the motion signal sent out by the motion sensor in your inner ear is normal. The problem lies inside your brain.
As the nerve coming out of motion sensor (vestibular nerve) goes inside your brain, it follows a specific pathway. Once inside your brain, these nerves branch out and make connections with different nerves coming out of other parts of your body. The connection with the nerves from your eyes help co-ordinate your motion with your vision. The connection with the nerves coming out of your spine and balance center of your brain help maintain balance and posture. The motion analyzer in your brain is complex and has different centers that connect and coordinate with each other. As a result, vertigo caused by central causes tends to be more complex than vertigo caused by peripheral causes. Here are some common central causes of vertigo:
Vertigo associated with Migraine headaches
Some people with migraine have episodes of vertigo associated with the headaches. Medically, these types of migraines are called vestibular migraine. Remember, vestibular labyrinth is the medical name for your inner ear motion sensor. The exact mechanism of what causes vertigo associated with migraine is still not properly understood. It is an area of ongoing medical research. However, the association between migraine and these types of vertigo is very clear.
If you have episodes of vertigo and have migraine headaches with them, you have vestibular migraine. The severity of your vertigo caused by vestibular migraine can vary widely. Some people have severe debilitating vertigo with nausea and vomiting while others just have mild symptoms.
It is important to distinguish between vestibular migraines and other central causes of migraine that include headache. If you have any other neurological signs or symptoms associated with vertigo and headaches, you need to work with your doctor to identify the actual cause of your vertigo before settling with the diagnosis of vestibular migraine. Vestibular migraine does not cause any other complicated neurological symptoms.
Vertigo associated with stroke
Yes, stroke can cause vertigo. In fact, stroke is always the major concern anytime you go to ER with new vertigo. Whenever the ER doctor sees a new patient with vertigo, he/she wants to make sure that it is not a stroke before considering other possible causes of vertigo. Different types of strokes affecting different parts of your brain can cause vertigo. As we learned earlier, the motion analyzer in your brain is complex and is connected to different parts of your brain receiving other nerves. It is hard to predict what exact symptoms you may have from vertigo caused by stroke. Here are a few warning signs that require further investigation to rule out stroke when you go to ER with a new vertigo:
- You have a prior history of stroke
- You have history of heart attacks or other clogged artery
- Along with vertigo, you have numbness, weakness or tingling in a part of your face or your body
- Your balance and coordination is significantly impaired in comparisons to your vertigo
- You have new visual problem (such as seeing double or unable to focus) associated with your vertigo
- Any problem with speaking or swallowing associated with your vertigo
Vertigo caused by multiple sclerosis
Multiple sclerosis or MS is a disease of your central nervous system caused by your immune system. Your immune system gets over-active and causes inflammation and damage of parts of your brain and your spinal cord. You have different symptoms at different times based on what part of your brain or spinal cord has been damaged. The exact symptoms of multiple sclerosis is hard to predict but any new unexplained weakness of a part of your body, any unexplained visual disturbance, any unexplained numbness, tingling, stiffness and similar symptoms may prompt your doctor to think about possible multiple sclerosis.
About 20% of patients with multiple sclerosis present with vertigo. Vertigo in multiple sclerosis is caused by inflammation and damage of one of the several places where your vestibular nerve travels and makes connections inside your brain.
What causes vertigo: things you need to note
As you can see there are so many things that can cause vertigo. It could be a challenge to find out what exactly caused your vertigo. However, you can help your doctor find the exact cause of your vertigo by noting a few things about your vertigo. If you can clearly communicate these things about your vertigo to your doctor, it will greatly help him/her find out what exactly caused your vertigo:
- How your vertigo started is important. Please note if it started abruptly or build up slowly.
- Note what exactly you were doing when your vertigo started.
- If you had episodes of vertigo, get your watch ready and note the exact duration of how long each episode of vertigo lasted.
- Note what makes your vertigo worse
- Note what makes your vertigo better
- Look in a mirror and note if your eye twitches with your vertigo
- Note how your vertigo has affected your balance
- Note if you feel nauseated with your vertigo
- Note if you have any other unusual symptom associated with your vertigo