Refractive eye surgery

Developed in collaboration with CASA Medical.

Refractive eye surgery is used to correct refractive errors such as near and far sightedness, astigmatism or presbyopia. Some procedures reshape the cornea, also known as keratorefractive surgery (LASIK, LASEK, conductive keratoplasty). While others implant a lens in the eye (phakic intraocular lenses and refractive lens exchange). The type of surgery is often dependent on type and degree of refractive error, certain patient factors and patient preference. 

Each procedure carries risks and complications that may have important aeromedical implications. These include temporary or permanent eye pain, blurry vision, dry eyes, halos, double vision, decreased visual acuity in low light, light sensitivity, and rarely eye infections, worsening vision and blindness. 

Pilots and controllers should consider carefully the pros and cons of refractive surgery, weighing the risks versus the benefits, and should not undergo a procedure just to meet the requirements of a medical certificate.

This is an area of rapid technological innovation, and not all procedures may be acceptable for certification. Pilots and controllers should consult with their treating specialists and review CASA or CAA NZ guidelines before undergoing procedures. There is a small risk of complications that may result in loss of certification. Pilots and controllers with mono-vision correction need to meet the CASA or CAA NZ standards and therefore may require prescription lenses. Pilots and controllers should be aware that near refraction can change with aging and prescription lenses may be required despite previous refractive surgery.

Pilots and controllers should be aware that there are requirements for ingoing optometry surveillance following laser and refractive eye surgery.

This guidance should be used for applicants with refractive disorders who have keratorefractive procedures and excludes intracorneal and phakic intraocular implants (see cataract guidelines).

Pilot and controller information

• Pilots and controllers should Inform their ME prior to undertaking refractive eye surgery.
• Pilots and controllers should ground themselves at the time of the surgery.
• Pilots and controllers should not fly or operate until cleared by CAA AvMed following surgery.

Aeromedical implications

Effect of aviation on the condition

• Aircraft air conditioning and low humidity at altitude may cause worsening of “dry eye” complication.
• Bright environmental light levels at altitude may cause/worsen light sensitivity and glare and halos.
• External lighting - bright aviation lights and strobes at night causing glare, haloes, starburst effects.
• Internal lighting and instrument lights may worsen light sensitivity.

Effect of the condition on aviation

• Incapacitation/impairment may occur due to the following:
  • Decrease in visual acuity.
  • Fluctuation in visual acuity at different times of the day.
  • Glare, halo, or ‘starburst’ effects due to corneal haze.
  • Loss of contrast sensitivity.
  • Reduced night vision.
  • Under or over correction.

Approach to medical certification

Based on the condition

• Reason for the procedure: degree of myopia, presbyopia, astigmatism, anisometropia
• Pre-operative refraction is stable in young applicants.

Based on treatment

• Keratorefractive surgery including:
  • LASIK,
  • LASEK and epi-LASEK
  • PRK,
  • SMILE
  • Conductive keratoplasty
  • Any other surgical procedure
• Completed any post-operative treatments, e.g. eyedrops

Demonstrated stability

• Vision and refraction have stabilised post-operatively.
• Absence of any visual symptoms, including haze, glare or haloes.
• Absence of complications of aeromedical significance.

Risk assessment protocol - information required

New cases

1. Specialist report after the surgery. The minimum time intervals for consideration for return to flying or operating after surgery are:

• Laser surgery
  • 6 weeks if refractive correction ≤ 3 dioptres
  • 3 months if refractive correction > 3 dioptres
• Radial keratotomy – 6 months

The report should outline the following:

• refraction before surgery
• date of surgery
• operative details (technique e.g., Femtosecond laser)
• size of ablation zone if applicable
• refraction after surgery
• stability of refraction over three paired serial measurements
• any sequelae including halo, haze, change in contrast sensitivity
• visual acuity in each eye at 30 - 50cm, 100cm and distance
• recent test of contrast sensitivity function (satisfactory contrast sensitivity is required, otherwise the certificate will be restricted as valid for day flying only)
• planned follow-up
• conductive keratoplasty requires 3 monthly assessments of refraction until acuity is stable.

2.  A CAA NZ Special Eye Report should outline the following:

• No symptoms such as halos, starbursts
• Distance visual acuity
• Dioptre correction stable - ≤ 0.25 dioptres
• Glare sensitivity testing passed
• Cornea clear

Renewal

• A CAA Special Eye Report is required at 12 months post-operatively and after 5 years after laser refractive surgery-
  • No symptoms such as halos, starbursts
  • Distance visual acuity stable - ≤ one line Snellen chart
  • Dioptre correction stable - ≤ 0.25 dioptres
  • Glare sensitivity testing passed
  • Cornea clear
• Subsequent screening by ME at the aviation medical for myopic deterioration.
• Ongoing ophthalmological review may be required for complex cases.
• Radial Keratotomy
  • Applicants whose eyes have stabilised following radial keratotomy must thereafter have an ophthalmological assessment every two years for Class 1 and 3 and every five years for Class 2 Medical Certificates.

ME aeromedical decision guide

If ALL the criteria in the table below the ME may issue a medical certificate. Evidence supporting the ME’s decision (for example reports and results) must be sent to CAA AvMed. 

ME must confirm	Tick
Renewal issue only
CAA AvMed recertified following refractive surgery
Visual acuity (corrected or uncorrected) meets class specific standards
Laser surgery – CAA Special Eye Report at 12 months and 5 years after surgery confirms ALL the following: No symptoms such as halos, starbursts Distance visual acuity stable - ≤ one line Snellen chart Dioptre correction stable - ≤ 0.25 dioptres Glare sensitivity testing passed Cornea clear
Corneal keratotomy Ophthalmology report and CAA Special Eye Report confirming the above Class 1 & 3 – every 2 years following procedure Class 2 – every 5 years following procedure
ME considers safe to certify

An AMC referral to CAA NZ AvMed is required if a pilot’s or controller’s condition does not meet all the above criteria and they consent to their condition being considered under flexibility to the CAR 67 rules.

ME letters

Refractive surgery medical certificate letter [DOCX 21 KB]