The inner ear balance (vestibular) system is one of three major bodily systems involved in balance. The other two are the visual system and proprioception or the sensation of movement and position of various parts of the body through pressure, tension and pain receptors located chiefly in muscles and tendons. All of these systems normally work together to enable us to maintain balance. If we lack input from one or more of these systems or the integration center of the brain fails to function properly, our balance will be correspondingly compromised. This article deals only with the vestibular system.
The sensory organs of the peripheral vestibular system are anatomically part of the inner ear and consist of parallel systems on each side that include three semicircular canals (oriented in the three planes of space) and two otolith organs-the utricle and the saccule. The primary role of the semicircular canals with their associated sensory cells is to permit us to sense angular acceleration and deceleration while the utricle and saccule enable us to sense linear acceleration or deceleration and to sense head position relative to gravity. Another critical role of the semicircular canals is to make possible the maintenance of visual fixation while our head/body is in motion. There is a reflexive connection between the semicircular canals and the muscles controlling eye movement.
To view illustrations of the vestibular organs, click here .
Vestibular system damage can come about by disease, injury, aging, vestibulotoxic drugs, metabolic disorders, vascular accidents and so forth. Its function can be temporarily affected by a number of medications or combinations of medications. The problem may be limited to the peripheral portion of the vestibular system or to the neural pathways and central vestibular projections.
Many audiologists have the training and equipment to perform detailed evaluation of the vestibular system and some are trained in rehabilitative procedures when they are necessary or can refer you to other medical specialists to work with you to bring you relief. If you are having problems with balance, consult with your audiologist about the advisability of a complete vestibular evaluation to delineate the nature of the problem and suggest corrective measures.
Symptoms of possible dysfunction range from relatively vague feelings of imbalance to severe dizziness accompanied by nausea and vomiting, virtually incapacitating the individual. The symptoms may be recurring or relatively constant. They may be present as isolated symptoms or in conjunction with other, related symptoms. Something as simple as changes in vision or new prescriptive lenses may produce a sense of imbalance. If the symptoms are associated with a change in prescriptions or dosage of existing medications, that may be the cause. Rather that trying to self-diagnose, it is strongly encouraged that you seek professional evaluation and care.