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Milomox28
12th May 2019, 14:51
Hello:

I know that astigmatism is limited to 200 degrees per eye ( according to ICAO regs) , however I have taken 2 First class medical exams ( FAA and Peruvian ) and none of them care about that as long as you have 20/20 in each eye. I have 300 degrees of astigmatism In one eye and 200 in the other.i wear RGP contacts.

My question is: if the airlines care about that in their medical exams?, I have seen some airlines such as Singapore airlines which clearly state in their entry requirements for F/O that you can’t have more than 200 degrees of astigmatism.

Best Regards

nonsense
13th May 2019, 02:40
Astigmatism, and lenses to correct for it, is normally specified in terms of the lens cylindrical power in diopters to correct, and the orientation of the lens in degrees (https://www.aao.org/eye-health/diseases/what-do-astigmatism-measurements-mean).
So, for example, you might require 2.75 diopters oriented at 120 degrees.
The orientation, the degrees number, is not an indication of the severity of the astigmatism.

Do you have your full lens prescription?

Sharklet
10th Sep 2022, 08:31
Hello,
I'm reviving this thread since I have a doubt on how to convert the 200 degrees of astigmatism to dioptres.

The orientation, the degrees number, is not an indication of the severity of the astigmatism.

Is there a calculation to convert the dioptres at a specified angle to the requirements for a CAAS medical?

iggy
10th Sep 2022, 13:01
Hello,
I'm reviving this thread since I have a doubt on how to convert the 200 degrees of astigmatism to dioptres.



Is there a calculation to convert the dioptres at a specified angle to the requirements for a CAAS medical?

Try calling them or droping them an email asking about your case. If you are paranoid about concealing your real name, just use a one time email address.

[email protected]
Phone: 62140797

nonsense
10th Sep 2022, 13:09
Hello,
I'm reviving this thread since I have a doubt on how to convert the 200 degrees of astigmatism to dioptres.

Astigmatism has both an orientation in degrees and a power in dioptres. Asking how to convert degrees to dioptres is a bit like asking how to convert heading to airspeed.

Is there a calculation to convert the dioptres at a specified angle to the requirements for a CAAS medical?

Bear in mind I'm just an engineer (not a pilot, nor an optometrist) who happens to own an altogether too interesting pair of eyes, which despite all their faults still work remarkably well.
I would be very surprised if the CAAS medical references the orientation angle of astigmatism. It doesn't really tell you anything useful about the severity of visual impairment. They will almost certainly only be interested in the power in dioptres of the astigmatism. The angle is needed to specify the corrective lenses, but does not give an indication of the degree of visual impairment.

Sharklet
11th Sep 2022, 16:00
Try calling them or droping them an email asking about your case. If you are paranoid about concealing your real name, just use a one time email address.

[email protected]
Phone: 62140797

Thanks, I'll drop them an e-mail. Not paranoid about revealing my name since I think there's no point in hiding it.

Astigmatism has both an orientation in degrees and a power in dioptres. Asking how to convert degrees to dioptres is a bit like asking how to convert heading to airspeed.

Bear in mind I'm just an engineer (not a pilot, nor an optometrist) who happens to own an altogether too interesting pair of eyes, which despite all their faults still work remarkably well.
I would be very surprised if the CAAS medical references the orientation angle of astigmatism. It doesn't really tell you anything useful about the severity of visual impairment. They will almost certainly only be interested in the power in dioptres of the astigmatism. The angle is needed to specify the corrective lenses, but does not give an indication of the degree of visual impairment.

Valid point. Still, I'm clueless then what to make of it. Best talk to those that write these rules then.

Sharklet
13th Sep 2022, 16:06
Interestingly, the CAAS responded promptly with the following:

We do not prescribe any numbers but as long as you are able to pass the respective eye tests during your Class One medical examination and Ophthalmologist examination, you should not have any issue with clearing CAAS Class One medical assessment. The eye tests to be done during CAAS Class One initial medical will include the following (unless clinically indicated):

Visual Acuity test with Snellen Chart
Ishihara Chart
Convergence Test
Near vision test
Colour Assessment and Diagnosis (CAD) test
Maddox Rod
Maddox Wing
Aviation Eye Photography screening



They also appended the PDF attached.

nonsense
13th Sep 2022, 17:01
So they're interested in the outcome, not the power of lens required to achieve it. I must say as an engineer, this reassures me...