Young applicants who undergo any type of refractive surgery for myopia before the refractive error has stabilised are at risk of recurrence of myopia, albeit to a lesser degree.
Radial keratotomy is a procedure rarely used these days being mostly limited to treating severe astigmatism. It consists in radial incisions of the cornea, allowing it to flatten.
Radial keratotomy may result in fluctuating visual acuity and sensitivity to glare. This can cause difficulties in the healing phase.
The long-term consequences of radial keratotomy are difficult to predict. Applicants should be reminded of this uncertainty as it may affect their chances of employment in the aviation industry.
Following radial keratotomy, the refraction takes time to stabilise to its new value. Flying is not permitted while the refraction is susceptible to change.
Evidence of stability generally requires:
An applicant who first presents with a history of radial keratotomy should provide:
MEs should have a low threshold for seeking advice by the CAA in cases of radial keratotomy.
Testing of visual performance with a bright light shining at the applicant should be sufficient to demonstrate any excessive vision impairment under glare condition. A formal determination can also be done by some optometrists.
An applicant who has undergone radial keratotomy in the past one year should be assessed as having a condition that is of aeromedical significance.
An applicant who has undergone radial keratotomy more than one year ago may be assessed as having a condition that is not of aeromedical significance if:
Provided that the certificate is endorsed as follows: