| GENERAL INFORMATION
|
|
| KEYWORDS
|
Category 1 aviation medical certificate, restrictions, vision
|
| FILE NO.
|
O-4739-01
|
| SECTOR (Marine or Aviation)
|
Aviation
|
| SPECIFIC JOB
|
Commercial pilot
|
| DIAGNOSIS (Primary, Secondary, etc.)
|
Transient visual loss, amaurosis fugax
|
| REVIEW
|
|
| DATE OF DETERMINATION
|
October 20, 2022
|
| MEMBER
|
Dr. Hugh Colin MacKay
|
| DETERMINATION
|
The member confirms the Minister of Transport’s decision to refuse to renew the applicant’s unrestricted category 1 aviation medical certificate.
|
| REASONS FOR THE DETERMINATION
Refusal to renew the applicant’s unrestricted category 1 aviation medical certificate (AMC) —
The applicant has operated as a commercial pilot, flying as the solo pilot on small aircraft for a small private charter company. In 2020, he experienced a transient visual loss affecting his left eye. The initial neurological assessment was that his symptoms were consistent with amaurosis fugax. As a result of this event, he had undergone an extensive medical work-up. Subsequently, the applicant was informed by Transport Canada (TC) that he was medically unfit to hold an AMC, as he did not meet the medical requirements of paragraphs 1.4(a), 3.4(a) and 4.1 of Standard 424.17(4) of the Canadian Aviation Regulations (CARs). However, when new medical information that could affect the decision became available, TC’s Civil Aviation Medicine (CAM) reviewed the new information and by letter in March 2022, informed the applicant of their new recommendation that he be issued a restricted AMC, to fly with an accompanying pilot. The applicant submitted his request to move forward with a review hearing to have the new TC decision reviewed by the Tribunal.
The applicant’s treating specialist was varied in her diagnosis of the applicant’s transient visual disturbance, first diagnosing amaurosis fugax, then saying it was not vascular in nature and classifying it as idiopathic, which does not rule out the diagnosis of amaurosis fugax. In her final report, she also referred to his risk for recurrence of a cerebrovascular event, which suggests he had experienced a cerebrovascular event. She has also stated there was no evidence of atherosclerosis, when there was some minor evidence identified on a carotid doppler. The two Aviation Medical Review Board (AMRB) neurologists have been consistent with their assessment of the event as amaurosis fugax. Given the inconsistencies with the treating specialist’s assessment, and the consistency of the two AMRB neurologists’ assessments, the member finds it reasonable for TC to use the diagnosis of amaurosis fugax in determining the applicant’s fitness to hold an unrestricted AMC.
In considering this case of amaurosis fugax, the medical witness for the Minister of Transport (Minister) referenced the section on Stroke and Transient Ischemic Attack (TIA) from the TC publication TP 13312 – Handbook for Civil Aviation Medical Examiners. This handbook identifies that the risk of a recurrent stroke following an initial TIA or stroke is about eight per cent per year, and that the risk of myocardial infarction is about two to three per cent per year. Therefore, the vast majority of applicants who have had a stroke will be considered permanently unfit. In the case of TIA, it does, however, allow for applicants with negative imaging of the brain, neck, and heart, and with minimal other risk factors to be considered for certification at three years after the event. In this case, the applicant had imaging of the head, neck, and heart with minimal findings, and he has minimal other risk factors, as supported by both the applicant’s specialist and the AMRB neurologists. The TC decision to issue a restricted certificate was made less than two years after the event, which was earlier than the recommended three years after the event.
The Minister’s witness testified that the Aeromedical Risk Assessment and Risk Management tool indicated that flexibility could be applied. It was felt the aeromedical risk was somewhat mitigated because of his general health status, the treatment of his medical risk factors, and the results of the medical investigations. Therefore, rather than waiting the full three years post event for assessment, as recommended, they were able to make the decision to issue the applicant a restricted AMC. The restriction of flying with an accompanying pilot, available to take control of flight operations should he have a recurrence of a TIA or stroke, was considered necessary to appropriately mitigate the flight safety risk resulting from his condition.
Other than the argument provided by the applicant that his risk of recurrence should be considered so low that he should be considered for an AMC without restrictions, he did not provide further testimony or evidence against the restrictions that had been applied to his certificate. The member finds that the Minister has proven, on a balance of probabilities, that it was reasonable to issue the applicant a restricted category 1 AMC.
|
|
| APPEAL
|
|
| DATE OF DECISION
|
|
| MEMBERS
|
|
| DECISION
|
|
| REASONS FOR THE DECISION
|
|
| OTHER/COMMENTS
|
|