There are lots of different words, terms and syndromes used to describe the primary symptoms of dizziness or imbalance. Not only is it confusing for people experiencing these problems, but it is also confusing for those trying to treat it!
You may have heard about syndromes such as:
- chronic subjective dizziness (CSD)
- phobic postural vertigo (PPV)
- space-motion discomfort (SMD)
- visual vertigo (VV)
The list goes on!
Each of these syndromes have been researched and investigated separately with a lot of them having many similarities in addition to some differences.
The main similarities across all these syndromes are:
- The primary symptoms are dizziness or unsteadiness
- The symptoms are provoked by movement
- The symptoms are chronic
- They impact on how a person’s vestibular or balance mechanisms function
- The symptoms cannot be attributed to a primary psychiatric disorder
- The symptoms cannot be attributed to a clear structural deficit
So are CSD, PPV, SMD and VV actually four separate conditions or are they all describing a broader, all-encompassing chronic, functional, vestibular syndrome?
The following ancient parable has been referenced by Philip Sloane way back in 1999 as well as likely numerous other vestibular specialists to help describe just this problem when trying to diagnose dizziness conditions:
A group of blind men heard that a strange animal, called an elephant, had been brought to the town. Out of curiosity, they said: “We must inspect and know it by touch”. So, they sought it out, and when they found it they groped about it. The first person, whose hand landed on the trunk, said, “This being is like a thick snake”. For another one whose hand reached its ear, it seemed like a kind of fan. As for another person, whose hand was upon its leg, said, the elephant is a pillar-like a tree trunk.
The moral of the parable is that humans have a tendency to claim absolute truth based on their limited, subjective experience as they ignore other people’s limited, subjective experiences which may be equally true.
So are the syndromes of CSD, PPV, SMD and VV all ‘true’ but just describing different parts of the same ‘elephant’?
A committee of international specialists on vestibular disorders, called the Barany Society, sat down and looked at just this question. They then published a consensus document in 2017 which described a diagnostic label and criteria for the ‘elephant’ called persistent postural-perceptual dizziness (PPPD). The benefit of this is that future research into the best way to diagnose, treat, prevent or manage this condition can now be standardised.
There have already been important research published into the best way to treat PPPD and vestibular rehabilitation with your Klint Neuro physiotherapist is an integral part.
References:
Staab, J.P et al. 2017. Diagnostic criteria for persistent postural-perceptual dizziness (PPPD): Consensus document of the committee for the Classification of Vestibular Disorders of the Bárány Society. Journal of Vestibular Research, Vol 27(4), 191-208.
Sloane, P.D and Dallara, J. 1999. Clinical research and geriatric dizziness: the blind men and the elephant. Journal of the American Geriatrics Society, Vol 47(1), 113-114.
‘Blind men and the elephant’. (2021). Wikipedia. Available at: https://en.wikipedia.org/wiki/Blind_men_and_an_elephant (Accessed: 26 May 2021)