23 M Military commission calculating astigmatism should SPH + CYL be added for mixed astigmatism?
I'm 23M from Eastern Europe. I recently had an eye exam at a military medical commission on 2025-12-08. I have autorefractor printouts from that exam and from a previous exam by another doctor. All measurements were taken with a dilated pupil. My refraction has been stable for several years.
Data from autorefractor:
- Most recent (2025-12-08) OD: SPH +1.75 / CYL −4.12 @ axis XX
- Previous measurements: similar, wide pupil
No prior eye surgery. No systemic diseases. No regular medications. Non-smoker, occasional alcohol.
Issue:
The commission asked me to calculate the "difference between the two principal meridians" by adding the sphere and cylinder (SPH + CYL). Based on that, I was declared fit. However, if the difference is calculated using the cylinder magnitude alone, I would be considered unfit according to their regulation: "Astigmatism of any type on any eye with a difference between the two principal meridians ≥4.0 D and <6.0 D." The regulation does not specify which method to use.
Questions for clinicians:
- In mixed astigmatism, is it ever correct to add sphere and cylinder to determine the difference between the principal meridians, or should the cylinder magnitude alone be used for this threshold?
- Does measuring with a dilated pupil on an autorefractor affect how this difference should be calculated in clinical or regulatory practice?
I have attached photos of my autorefractor printouts from both visits, with all personal details redacted.
Thanks for any clear, practice-based input.
Posted Dec 9, 2025, 8:45 AM UTC