1Statement of Principles concerning optochiasmatic arachnoiditis (Balance of Probabilities) (No. 96 of 2025)

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RMA Australian Government Coat of Arms

 

Statement of Principles

concerning

OPTOCHIASMATIC ARACHNOIDITIS (Balance of Probabilities)

(No. 96 of 2025)

The Repatriation Medical Authority determines the following Statement of Principles under subsection 196B(3) of the Veterans' Entitlements Act 1986.

 

Dated 24 October 2025

 

 

 

 

 

 

 

 

 

 

Professor Terence Campbell AM

Chairperson

by and on behalf of

The Repatriation Medical Authority

 

 

Contents

1 Name

2 Commencement

3 Authority

4 Repeal

5 Application

6 Definitions

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

8 Basis for determining the factors

9 Factors that must exist

10 Relationship to service

11 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 optochiasmatic arachnoiditis (Balance of Probabilities) (No. 96 of 2025).

1.                Commencement

              This instrument commences on 24 November 2025.

1.                Authority

This instrument is made under subsection 196B(3) of the Veterans' Entitlements Act 1986.

1.                Repeal

The Statement of Principles concerning optochiasmatic arachnoiditis (Balance of Probabilities) (No. 58 of 2016) (Federal Register of Legislation No. F2016L00568) made under subsections 196B(3) and (8) of the VEA is repealed.

1.                Application

This instrument applies to a claim to which section 120B of the VEA or section 339 of the Military Rehabilitation and Compensation Act 2004 applies.

1.                Definitions

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

1.                Kind of injury, disease or death to which this Statement of Principles relates
2.           This Statement of Principles is about optochiasmatic arachnoiditis and death from optochiasmatic arachnoiditis.

Meaning of optochiasmatic arachnoiditis

1.           For the purposes of this Statement of Principles, optochiasmatic arachnoiditis means chronic inflammation of the arachnoid membrane surrounding the optic chiasm and intracranial optic nerves, resulting in damage to these structures from fibrosis and the formation of adhesions, and typically presenting with progressive visual loss.

Death from optochiasmatic arachnoiditis

1.           For the purposes of this Statement of Principles, optochiasmatic arachnoiditis, in relation to a person, includes death from a terminal event or condition that was contributed to by the person's optochiasmatic arachnoiditis.

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

1.                Basis for determining the factors

On the sound medical‑scientific evidence available, the Repatriation Medical Authority is of the view that it is more probable than not that optochiasmatic arachnoiditis and death from optochiasmatic arachnoiditis can be related to relevant service rendered by veterans 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.

1.                Factors that must exist

At least one of the following factors must exist before it can be said that, on the balance of probabilities, optochiasmatic arachnoiditis or death from optochiasmatic arachnoiditis is connected with the circumstances of a person's relevant service:

1.           having a tuberculosis infection of the leptomeninges surrounding the optic chiasm or intracranial optic nerves before clinical onset or clinical worsening.
2.            being treated with antibiotics for tuberculous meningitis at least 30 days before clinical onset or clinical worsening
3.           having a subarachnoid haemorrhage or bleeding into the subarachnoid space before clinical onset or clinical worsening.
4.           having muslin or cotton wrapping or packing, left in situ after a surgical procedure which involves or adjacent to the optic chiasm, at least 30 days before clinical onset or clinical worsening. 
5.           having received a cumulative equivalent dose of at least 60 sieverts of ionising radiation to the region of the optic chiasm before clinical onset or clinical worsening.

Note: cumulative equivalent dose is defined in the Schedule 1 - Dictionary.

1.           having an intrathecal myelogram or intrathecal treatment with iophendylate (Pantopaque or Myodil) before clinical onset or clinical worsening.

2.           inability to obtain appropriate clinical management for optochiasmatic arachnoiditis before clinical worsening.

3.            Relationship to service

4.           The existence in a person of any factor referred to in section 9, must be related to the relevant service rendered by the person.

5.           The clinical worsening aspect of factors set out in section 9 apply only to material contribution to, or aggravation of, optochiasmatic arachnoiditis where the person's optochiasmatic arachnoiditis was suffered or contracted before or during (but did not arise out of) the person's relevant service.

6.            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 9 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(3) 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 6

1               Definitions

In this instrument:

                             cumulative equivalent dose means the total dose of ionising radiation received by the particular organ or tissue from external exposure, internal exposure or both, apart from normal background radiation exposure in Australia, calculated in accordance with the methodology set out in Guide to calculation of 'cumulative equivalent dose' for the purpose of applying ionising radiation factors contained in Statements of Principles determined under Part XIA of the Veterans' Entitlements Act 1986 (Cth), Australian Radiation Protection and Nuclear Safety Agency, as in force on 2 August 2017.

Note 1: Examples of circumstances that might lead to exposure to ionising radiation include being present during or subsequent to the testing or use of nuclear weapons, undergoing diagnostic or therapeutic medical procedures involving ionising radiation, and being a member of an aircrew, leading to increased levels of exposure to cosmic radiation.

Note 2: For the purpose of dose reconstruction, dose is calculated as an average over the mass of a specific tissue or organ. If a tissue is exposed to multiple sources of ionising radiation, the various dose estimates for each type of radiation must be combined.

                             MRCA means the Military Rehabilitation and Compensation Act 2004.

                               optochiasmatic arachnoiditis—see subsection 7(2).

                             relevant service means:

(a)          eligible war service (other than operational service) under the VEA;

(b)          defence service (other than hazardous service and British nuclear test defence service) under the VEA; or

(c)          peacetime service under the MRCA.

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

                             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.

                             VEA means the Veterans' Entitlements Act 1986.