Guidance following eye surgery

Refractive, cataract, glaucoma and retinal surgery, and collagen cross linking.

     

1. Refractive surgery

Prerequisites

• For Radial Keratotomy (RK), stability of refraction must be demonstrated before recertification. Each treated eye should show less than 0.75 dioptres diurnal variation.

• Applicants should have refraction and slit lamp examination. There should be no post- operative complications (e.g. corneal scarring) that might impact on flight safety.

• Glare sensitivity and mesopic contrast sensitivity should be satisfactory. Class 1 applicants should be formally tested at an AeMC, and have no dysphotopsia symptoms such as glare, halos (rings of light) or starbursts (streaking of point lights). In cases of doubt referral to a consultant aviation ophthalmologist should be considered. For Class 2, formal testing is not required but symptom inquiry should be carried out and there should be no dysphotopsia symptoms such as glare, halos or starbursts.

• A report must be provided from the centre that carried out the surgery and this should conform to the CAA’s guidance on ophthalmic reports. Details must include dates and type of surgery performed, pre-operative refraction, and details of any complications (or a statement that no complications have occurred).

Revalidation Periods

All pilots must be assessed as unfit at the time of surgery. Assessment for restoration of fitness status should be carried out one week after the satisfactory cessation of post-operative medication when no longer necessary. Further reviews will be required if stability of refraction is in doubt or there are adverse effects. Guidance on the most common procedures is given below. Further guidance on other procedures should be sought from the AME or CAA Medical Assessor before the applicant is listed for surgery.

Photo Refractive Keratectomy (PRK)

Class 1 applicants or holders should undergo formal testing as above at an AeMC at 6 months and have an ophthalmological review with a consultant ophthalmologist. This should confirm a satisfactory surgical result and freedom from adverse side-effects. Restoration of fitness status before 6 months (but not less than three months) may sometimes be possible if only a low level of refractive error has been treated and early stability of refraction is demonstrated.

Class 2 applicants do not require formal testing for dysphotopsia but should confirm absence of glare, halos and starburst. Review can be with a local consultant ophthalmologist.

Laser Assisted in-Situ Epithelial Keratomileusis (LASEK)

As for PRK for all classes.

Laser Assisted In-situ Keratomileusis (LASIK)

Class 1: refraction should be assessed at 4 and 6 weeks at an AeMC and an ophthalmological review undertaken with a consultant ophthalmologist at the 6 week point before recertification can be considered.

Class 2 – refraction should be assessed at 4 and 6 weeks with confirmation of absence of dysphotopsia symptoms and local consultant ophthalmological review at the 6 week point before recertification can be considered.

Clear Lens Exchange

Policy as for cataract surgery; please see below.

Conductive Keratoplasty

As for LASIK, but no return to fit status of any class until 3 months. Due to the higher incidence of refraction regression following this procedure, ongoing 3 monthly refractions will be required until stability is confirmed.

Cataract Surgery

Multifocal implants may be offered by the pilot's surgeon before cataract surgery as an alternative to traditional monofocal lens implants. The CAA does not recommend or approve a particular intraocular lens (IOL) for certification.

A review of randomised controlled trials studying multifocal versus monofocal intraocular lenses after cataract extraction was published by the Cochrane Collaboration in 2016. It reported that distance visual acuity was similar in the multifocal and monofocal groups but people with multifocal lenses achieved better near vision overall and were less dependent on spectacles. Adverse subjective visual phenomena, particularly halos, were common and troublesome in people receiving multifocal IOLs.

There was some evidence that contrast sensitivity may be lower in people receiving multifocal IOLs. There were no significant differences between IOLs with respect to objective glare.

The information in this review indicates that monofocal IOLs are likely to be less problematic than multi-focal IOLs for the issue of an aeromedical certificate. However, the decision to proceed with a multifocal implant should be made by the applicant and their surgeon, considering the potential impact on the applicant’s occupation. Applicants should be aware of the possible adverse effects from any type of lens as aeromedical certification may not be possible if they occur.

Micromonovision* after both laser refractive surgery and intraocular lens implantation may be permitted subject to freedom from adverse effects and glasses being available which reverse the micromonovision* and restore both eyes in full focus at distant, intermediate and near.

*In traditional monovision, one eye was set for distant vision and the other for near using surgical strategies that created a large difference (typically 2- 3.5 dioptres) between the eyes. Micro-monovision aims to establish a reduced interocular dioptric power difference, typically of the order of 0.75D and not greater than 2D, such that a large intermediate zone of binocularity is achieved.

Fitness Assessment

Intraocular surgery will generally result in an unfit assessment for at least 6 weeks. Fitness can be reassessed following complete recovery from surgery. Assessment should include a comprehensive eye examination to include assessment of contrast and glare sensitivities and mesopic contrast sensitivity. For Class 1 and 3 applicants, this should be conducted with the vision specialist at an Aeromedical Centre. Class 2 applicants may undertake this with their local vision specialist. A report from this assessment should be provide to the applicant’s AME along with a detailed report from the specialist who performed the procedure following the template for Ophthalmic medical reports provided on the CAA website. This report should include the date of surgery, the type of implant used and confirmation that the pilot has fully recovered from surgery and that there are no post-operative complications.

Glaucoma Surgery

A report shall be provided from the consultant ophthalmologist who performed the procedure and should include full details of the treatment carried out, current management, postoperative distant and near visual acuities, and up to date visual field results (please refer to separate guidance material on visual fields).

For Class 1 an assessment by a consultant aviation ophthalmologist may be required.

 

Procedure	Likely time before reassessment for certification
Trabeculectomy or treatment with external glaucoma devices**	3 months
Stenting	6 weeks
Selective laser or argon laser trabeculoplasty	1 week
Other procedures	Assessment once recovery made

** Glaucoma drainage devices create alternate channels to drain the aqueous humour from the anterior chamber through a long tube to a reservoir placed at the equator of the globe. Glaucoma drainage devices are being used more frequently but usually indicate that the glaucoma being treated is particularly severe and has not responded to medication, laser or traditional trabeculectomy surgery OR that the patient has an atypical form of glaucoma such as neovascular glaucoma, where it may be used as the primary procedure.

Retinal surgery

A report should be obtained from the consultant ophthalmologist who performed the procedure based on a review at 3 months. This should include full details of the procedure, and in particular whether any medical gases were used; post-operative recovery should be complete and current visual acuities and Esterman visual field analysis should be provided. The report should either confirm absence of post-operative ocular motility problems (except with vitrectomy) or incorporate an orthoptic report and/ or strabismology report.

For Class 1, an assessment by a consultant aviation ophthalmologist may be required before recertification can be considered.

Collagen Cross Linking

Due to the risk of corneal haze following this procedure, assessment for dysphotopsia is required (see refractive surgery guidance).

Class 1 - Refraction at 2 months and then further refraction and full dysphotopsia testing and consultant aviation ophthalmological review at 3 months.

Class 2 - Refraction at 2 months and then review by a local consultant ophthalmologist at 3 months to include refraction and confirmation of absence of dysphotopsia symptoms.