Many people complain of dizziness, usually describing it as a lightheaded feeling, or a feeling that darkness is descending over their head and they feel they may faint. But when someone describes it as a sensation of everything spinning around, and can even tell you in which direction, then that is a special form of dizziness called vertigo.
All forms of vertigo are accompanied by a special type of eye movement called nystagmus. If you look at the eyes of someone having an attack of vertigo, you’ll see them moving together slowly in one direction and then quickly back in the opposite direction. It’s the rapid eye movement that is interpreted by our brain as the room spinning around us. If severe and prolonged, this can literally make one sea sick, with nausea and vomiting.
Vertigo can have many different causes. It is usually classified as either central or peripheral.
Central vertigo originates in the brain or spinal cord, and can arise from blocked blood vessels in the brain, from diseases like multiple sclerosis, or from migraine attacks is usually accompanied by other symptoms. Loss of coordination, double vision, difficulty speaking, weakness or numbness or severe headache would all point to a central cause of vertigo. Except in the case of migraines, central vertigo generally is a symptom of a severe underlying disease and has a poorer prognosis than peripheral vertigo.
Vertigo occurring without any other symptoms — such as you described — is usually peripheral peripheral, meaning that it originates in the nerves that serve the vestibular apparatus, or in the vestibular apparatus itself.
The vestibular apparatus consists of the three semicircular canals — small interconnected canals each containing a little calcium particle that is in contact with tiny hair cells in the interior of the canal. When we move, the calcium chip in each canal shifts and stimulates different hair cells which send signals to the brain telling it if the position of our head has changed and allowing us to orient ourselves in space.
In diagnosing peripheral vertigo, the duration and cause of the attacks is important to document. You unfortunately did not tell us how long an attack lasts, but I would assume it’s only seconds, since vertigo is so uncomfortable that you probably immediately move your head to make it stop.
Other forms of peripheral vertigo include:
- Meniere’s disease, which can produce quite disabling vertigo, and includes hearing loss and tinnitus, a whistling or buzzing sound in the ear. The attacks may last for hours, and not all three components of the condition are always present at the same time. Attacks of vertigo tend to recur, and ultimately the hearing loss may be severe.
- Vestibular neuronitis causes a severe vertigo that is accompanied usually by nausea and vomiting. The affected person must lie still in bed to avoid vomiting. The cause is not known but it is assumed that an inflammation of the vestibular apparatus produces it. Fortunately the attacks only last a few days, and they do not commonly recur.
- Vertigo can also occur, often accompanied by deafness, after pressure trauma to an ear, as in scuba diving.
Brief vertigo that is caused by a rapid movement of the head, such as rolling over in bed, is called benign positional vertigo (BPV). Benign because it is not produced by any serious or life threatening disease, and positional because it is brought on by changes in position.
BPV is thought to be due to accumulation of debris in the semicircular canals that interferes with their proper functioning. It usually goes away by itself, although it can recur as it did in your case. Drugs are usually not very helpful, since the episodes are brief, and a person with BPV quickly learns to avoid the motions that produce it. If the symptom occurs very frequently and is difficult to control, a treatment called the Epley canalith repositioning maneuver will often cause the debris to fall out of the semicircular canal and stop the attacks. An ear, nose and throat specialist would be the person most likely to be familiar with this maneuver.