Acoustic shock injury (ASI).
CONCLUSIONS
The potential severity and persistence of ASI symptoms has significant clinical and medico-legal implications. With the rapid growth of call centres around the world, professionals providing tinnitus and hyperacusis therapy are increasingly likely to encounter some or all of the cluster of ASI symptoms in their clients.


BACKGROUND
Acoustic shock injury (ASI), occurring as a result of exposure to a sudden unexpected loud sound, has been observed to cause a specific and consistent pattern of neurophysiological and psychological symptoms. These include aural pain, tinnitus, hyperacusis/phonophobia, vertigo and other unusual symptoms such as numbness or burning sensations around the ear. A range of emotional reactions including trauma, anxiety and depression can develop. Call centre staff using a telephone headset or handset are vulnerable to ASI because of the increased likelihood of exposure, close to their ear(s), of sudden unexpected loud sounds randomly transmitted via the telephone line.


CONCLUSIONS
This paper presents an overview of a study of 103 people exposed to 123 acoustic incidents, and of the proposed neurophysiological mechanism of ASI, in particular tonic tensor tympani syndrome (TTTS). An understanding of TTTS has the potential to provide insight into the neurophysiological and psychological development of tinnitus and hyperacusis and the association with high levels of emotional trauma and anxiety.


RESULTS
ASI rehabilitation is discussed.
Westcott
Myriam
M
Dineen and Westcott Audiologists, Heidelberg, Victoria, Australia. m_daudio@tpg.com.au
D001007:Anxiety / Q000209:etiology; D003863:Depression / Q000209:etiology; D006317:Hearing Loss, Noise-Induced / Q000150:complications*; D006801:Humans; D012001:Hyperacusis / Q000175:diagnosis / Q000209:etiology / Q000534:rehabilitation; D010146:Pain / Q000175:diagnosis / Q000209:etiology; D014012:Tinnitus / Q000209:etiology* / Q000503:physiopathology / Q000534:rehabilitation; D014432:Tympanic Membrane / Q000503:physiopathology