The dominant driving force to maintain balance originates from the inner ear. However, imbalance can result from a wide variety of causes, the most common of which occur as a result of the vestibular system (inner ear), visual system (eyes), or somatosensory system (body awareness) disorders. The somatosensory system involves touch, pressure, and joint position sense. Each system is an individual sense and has a responsibility to send information to the central nervous system (CNS), which is primarily the brain and cerebellum. Vestibular input sends information regarding our movements in relation to our postural control; our visual system sends information regarding our visual world; and the somatosensory system sends information pertaining to our contact to our exterior environment (our feet on the ground is the best example). If all of these systems are coordinated, we are stable and balanced.
There are some cases where the peripheral systems are working correctly: however, the patient may be having symptoms of dizziness and vertigo due to problems in the central nervous system. In these cases, our physician must evaluate many factors: are the signals not reaching the CNS, are there disease processes within the CNS, or are the output and reaction signals not function properly? Below are a number of potential possibilities that our physician can address, either through treatment or referral.
Cervical vertigo may be due to inflammatory and/or degenerative changes in the cervical spine or neck musculature. The neck muscles are constantly sending nerve impulses to the balance centers of the brain to help maintain equilibrium. Spasm (tenseness) of the muscles can result in an abnormal nerve discharge, leading to unsteadiness or dizziness. In this case a referral to a spine specialist may be necessary to resolve the underlying condition.
Circulation Changes or Vertebrobasilar Insufficiency
Circulation Changes or Vertebrobasilar Insufficiency (VBI) may cause dizziness; this is predominately due to decreased blood flow in the vertebral vessels when the head is turned in a particular position. Any interference with the circulation to the delicate inner ear structures or their central connections may result in dizziness, at times with hearing loss and tinnitus. Blood vessel spasms may cause sudden onset dizziness. Spasms result from certain drugs such as caffeine (coffee) and nicotine (cigarettes). Migraines may cause nausea, vomiting, and other neurological symptoms. Small vessel disease involved with aging in the brain stem also causes complaints of disequilibrium and/or gait instability.
Acoustic Tumors or Skull Base Tumors cause hearing loss, tinnitus, and dizziness along with other neurological symptoms in the later development. These are usually benign tumors involving the hearing and balance nerve which usually affects only one ear.