The unknown factor revealed
it has been immortalised in public memory by the Alfred Hitchcock thriller Vertigo . Yet only those who suffer from it know the feeling. Anything from the sound of the buzz on the telephone to music or cheering at a sporting event can give vertigo to some people. Vertigo is a sensation of whirling motion, tending to result in a loss of balance and, sometimes, consciousness.
Some observations based on research conducted four years ago has thrown new light on the reasons behind vertigo. A study of a pile of old skulls conducted by Llyod Minor and his colleagues at the Johns Hopkins Center for Hearing and Balance in Baltimore, Maryland, usa , had described a rare disorder known as Superior Canal Dehiscence Syndrome ( scds ) in 1995.
The study had indicated that the weakness is largely hereditary. Minor and his team has traced the problem to a fracture in the temporal bone, directly above the ear's upper balance canal. The hole means that noises are not processed properly and, instead, create strong vibrations. These vibrations, in turn, lead to vertigo.
Now, it has been revealed that around two per cent of people are predisposed to develop this condition because they have abnormally thin temporal bones. Normally, the bone is 1 millimetre thick. In scds patients, the thickness is just one-tenth of that. A slight injury or even coughing can crack the bone, says Minor.
Many people suffering from vertigo must be relieved to know that the disorder has a physical cause and is not related to the brain. Minor and his team have already treated several patients by repairing the cracked bone.