Statement of Principles

concerning

HYPERACUSIS
(Reasonable Hypothesis)

(No. 27 of 2021)

The Repatriation Medical Authority determines the following Statement of Principles under subsection 196B(2) of the Veterans' Entitlements Act 1986.

Dated                             24 December 2020

Contents

1 Name

2 Commencement

3 Authority

4 Application

5 Definitions

6 Kind of injury, disease or death to which this Statement of Principles relates

7 Basis for determining the factors

8 Factors that must exist

9 Relationship to service

10 Factors referring to an injury or disease covered by another Statement of Principles

Schedule 1 - Dictionary

1 Definitions

1               Name

This is the Statement of Principles concerning hyperacusis (Reasonable Hypothesis) (No. 27 of 2021).

2               Commencement

              This instrument commences on 25 January 2021.

3               Authority

This instrument is made under subsection 196B(2) of the Veterans' Entitlements Act 1986.

4               Application

This instrument applies to a claim to which section 120A of the VEA or section 338 of the Military Rehabilitation and Compensation Act 2004 applies.

5               Definitions

The terms defined in the Schedule 1 - Dictionary have the meaning given when used in this instrument.

6               Kind of injury, disease or death to which this Statement of Principles relates

(1)          This Statement of Principles is about hyperacusis and death from hyperacusis.

Meaning of hyperacusis

(2)          For the purposes of this Statement of Principles, hyperacusis:

(a)          means a disorder of sound tolerance or perception in which there is increased sensitivity or decreased tolerance to certain everyday sounds at levels that would not disturb most individuals; and

(b)           causes significant distress and impairment in social, occupational, recreational, and other day-to-day activities; and

(c)           must have persisted for at least three months.

Note 1: The sounds may be perceived as uncomfortably loud, unpleasant, frightening or painful.

Note 2: Sounds generated within the body may also cause hyperacusis.

Death from hyperacusis

(3)          For the purposes of this Statement of Principles, hyperacusis, in relation to a person, includes death from a terminal event or condition that was contributed to by the person's hyperacusis.

Note: terminal event is defined in the Schedule 1 - Dictionary.

7               Basis for determining the factors

The Repatriation Medical Authority is of the view that there is sound medical‑scientific evidence that indicates that hyperacusis and death from hyperacusis can be related to relevant service rendered by veterans, members of Peacekeeping Forces, or members of the Forces under the VEA, or members under the MRCA.

Note: MRCA, relevant service and VEA are defined in the Schedule 1 - Dictionary.

8               Factors that must exist

At least one of the following factors must as a minimum exist before it can be said that a reasonable hypothesis has been raised connecting hyperacusis or death from hyperacusis with the circumstances of a person's relevant service:

(1)          being exposed to a peak sound pressure level at the tympanic membrane of at least 140 dB(C) before the clinical onset of hyperacusis;

Note: dB(C) is defined in the Schedule 1 - Dictionary.

(2)          being exposed to a sound pressure level at the tympanic membrane of at least 85 dB(A) as an 8-hour time-weighted average (TWA) with a 3‑dB exchange rate for a cumulative period of at least six months before the clinical onset of hyperacusis;

Note: dB(A) and time-weighted average (TWA) with a 3-dB exchange rate are defined in the Schedule 1 - Dictionary.

(3)          having sensorineural hearing loss at the time of the clinical onset of hyperacusis;

(4)          having acoustic shock at the time of the clinical onset of hyperacusis;

Note: acoustic shock is defined in the Schedule 1 - Dictionary.

(5)          having an episode of otitic barotrauma within the 30 days before the clinical onset of hyperacusis;

Note: Otitic barotrauma is also known as otic barotrauma.

(6)          being exposed to an explosive blast within the 30 days before the clinical onset of hyperacusis;

(7)          having concussion or moderate to severe traumatic brain injury within the 30 days before the clinical onset of hyperacusis;

(8)          having blunt trauma to the head causing a fracture of the temporal bone within the 30 days before the clinical onset of hyperacusis;

(9)          having stapedectomy or surgery involving the insular cortex or another part of the brain involved in central auditory processing within the 30 days before the clinical onset of hyperacusis;

(10)      having an inner ear disorder of the affected ear from the specified list of inner ear disorders at the time of the clinical onset of hyperacusis;

Note: specified list of inner ear disorders is defined in the Schedule 1 - Dictionary.

(11)      having Meniere's disease at the time of the clinical onset of hyperacusis;

(12)      having paralysis of the facial nerve on the affected side at the time of the clinical onset of hyperacusis;

Note 1: The facial nerve is also known as the seventh cranial nerve.

Note 2: Facial nerve paralysis is also known as Bell's palsy.

Note 3: Conditions that can cause paralysis of the facial nerve include autoimmune disease, multiple sclerosis and viral infection.

(13)      having a viral or bacterial infection from the specified list of viral or bacterial infections within the 30 days before the clinical onset of hyperacusis;

Note: specified list of viral or bacterial infections is defined in the Schedule 1 - Dictionary.

(14)      having dysfunction of the stapedius muscle or the tensor tympani muscle on the affected side at the time of the clinical onset of hyperacusis;

(15)      having a middle cerebral artery aneurysm at the time of the clinical onset of hyperacusis;

(16)      having a cerebrovascular accident within the 30 days before the clinical onset of hyperacusis;

(17)      having multiple sclerosis at the time of the clinical onset of hyperacusis;

(18)      undergoing withdrawal following long-term benzodiazepine use within the seven days before the clinical onset of hyperacusis;

Note: long-term benzodiazepine use is defined in the Schedule 1 - Dictionary.

(19)      being exposed to a peak sound pressure level at the tympanic membrane of at least 140 dB(C) before the clinical worsening of hyperacusis;

Note: dB(C) is defined in the Schedule 1 - Dictionary.

(20)      being exposed to a sound pressure level at the tympanic membrane of at least 85 dB(A) as an 8-hour time-weighted average (TWA) with a 3‑dB exchange rate for a cumulative period of at least six months before the clinical worsening of hyperacusis;

Note: dB(A) and time-weighted average (TWA) with a 3-dB exchange rate are defined in the Schedule 1 - Dictionary.

(21)      having sensorineural hearing loss at the time of the clinical worsening of hyperacusis;

(22)      having acoustic shock at the time of the clinical worsening of hyperacusis;

Note: acoustic shock is defined in the Schedule 1 - Dictionary.

(23)      having an episode of otitic barotrauma within the 30 days before the clinical worsening of hyperacusis;

Note: Otitic barotrauma is also known as otic barotrauma.

(24)      being exposed to an explosive blast within the 30 days before the clinical worsening of hyperacusis;

(25)      having concussion or moderate to severe traumatic brain injury within the 30 days before the clinical worsening of hyperacusis;

(26)      having blunt trauma to the head causing a fracture of the temporal bone within the 30 days before the clinical worsening of hyperacusis;

(27)      having stapedectomy or surgery involving the insular cortex or another part of the brain involved in central auditory processing within the 30 days before the clinical worsening of hyperacusis;

(28)      having an inner ear disorder of the affected ear from the specified list of inner ear disorders at the time of the clinical worsening of hyperacusis;

Note: specified list of inner ear disorders is defined in the Schedule 1 - Dictionary.

(29)      having Meniere's disease at the time of the clinical worsening of hyperacusis;

(30)      having paralysis of the facial nerve on the affected side at the time of the clinical worsening of hyperacusis;

Note 1: The facial nerve is also known as the seventh cranial nerve.

Note 2: Facial nerve paralysis is also known as Bell's palsy.

Note 3: Conditions that can cause paralysis of the facial nerve include autoimmune disease, multiple sclerosis and viral infection.

(31)      having a viral or bacterial infection from the specified list of viral or bacterial infections within the 30 days before the clinical worsening of hyperacusis;

Note: specified list of viral or bacterial infections is defined in the Schedule 1 - Dictionary.

(32)      having dysfunction of the stapedius muscle or the tensor tympani muscle on the affected side at the time of the clinical worsening of hyperacusis;

(33)      having a middle cerebral artery aneurysm at the time of the clinical worsening of hyperacusis;

(34)      having a cerebrovascular accident within the 30 days before the clinical worsening of hyperacusis;

(35)      having multiple sclerosis at the time of the clinical worsening of hyperacusis;

(36)      undergoing withdrawal following long-term benzodiazepine use within the seven days before the clinical worsening of hyperacusis;

Note: long-term benzodiazepine use is defined in the Schedule 1 - Dictionary.

(37)      inability to obtain appropriate clinical management for hyperacusis.

9               Relationship to service

(1)          The existence in a person of any factor referred to in section 8, must be related to the relevant service rendered by the person.

(2)          The factors set out in subsections 8(19) to 8(37) apply only to material contribution to, or aggravation of, hyperacusis where the person's hyperacusis was suffered or contracted before or during (but did not arise out of) the person's relevant service.

10           Factors referring to an injury or disease covered by another Statement of Principles

In this Statement of Principles:

(1)          if a factor referred to in section 8 applies in relation to a person; and

(2)          that factor refers to an injury or disease in respect of which a Statement of Principles has been determined under subsection 196B(2) of the VEA;

then the factors in that Statement of Principles apply in accordance with the terms of that Statement of Principles as in force from time to time.

Schedule 1 - Dictionary  

Note:               See Section 5

1               Definitions

In this instrument:

                             acoustic shock means the development of acoustic shock symptoms within 30 days of being exposed to a brief, sudden, unexpected, loud sound.

Note: acoustic shock symptoms is also defined in the Schedule 1 - Dictionary.

                             acoustic shock symptoms means the acoustic shock symptoms identified in Work Health and Safety (Managing Noise and Preventing Hearing Loss at Work) Code of Practice 2015, including:

(a)          a feeling of fullness in the ear;

(b)          burning sensations or sharp pain around or in the ear;

(c)          dizziness;

(d)          hypervigilance;

(e)          numbness, tingling or soreness down the side of face, neck or shoulder; and

(f)           tinnitus.

Note: The sounds associated with the development of acoustic shock symptoms include crackles, hisses, whistles, shrieks and high-pitched noises.

                             dB(A) means the sound pressure level in decibels measured by a sound level meter using a type A electronic filter.

                             dB(C) means the sound pressure level in decibels measured by a sound level meter using a type C electronic filter.  The type C filter is used to measure peak or impact sound pressure levels.

                             hyperacusis—see subsection 6(2).

                               long-term benzodiazepine use means taking a benzodiazepine daily for at least three months.

                             MRCA means the Military Rehabilitation and Compensation Act 2004.

                             relevant service means:

(a)          operational service under the VEA;

(b)          peacekeeping service under the VEA;

(c)          hazardous service under the VEA;

(d)          British nuclear test defence service under the VEA;

(e)          warlike service under the MRCA; or

(f)           non-warlike service under the MRCA.

Note: MRCA and VEA are also defined in the Schedule 1 - Dictionary.

                             specified list of inner ear disorders means:

(a)          lateral semicircular canal dysplasia;

(b)          perilymphatic fistula;

(c)          stapes hypermobility; or

(d)          superior semicircular canal dehiscence.

                             specified list of viral or bacterial infections means:

(a)          neurosyphilis;

(b)          Lyme disease;

(c)          Orientia tsutsugamushi infection (scrub typhus); or

(d)          Rickettsia prowazekii infection.

                             terminal event means the proximate or ultimate cause of death and includes the following:

(a)           pneumonia;

(b)           respiratory failure;

(c)           cardiac arrest;

(d)           circulatory failure; or

(e)           cessation of brain function.

                               time-weighted average (TWA) with a 3-dB exchange rate means the time-weighted average noise exposure level calculated according to the following formulae and shown in the table:

TWA = 10.0  Log(D/100) + 85

where D = daily dose; and

D = [C1/T1 + C2/T2 + …..+ Cn/Tn]  100

where               Cn = total time of exposure at a specified noise level; and

Tn = exposure duration for which noise at this level becomes hazardous

Table of noise exposure levels and

durations based on 3-dB(A) exchange rate

                             Source: National Institute of Occupational Safety and Health 1998 Guidelines Publication No. 98-126

                             VEA means the Veterans' Entitlements Act 1986.