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Skewed topography


27 year old woman wants Lasik.


-5.75 +0.50 x 95 20/20

– 5.25+0.50 x 85 20/20

Pachs 574 OD, 599 OS

 Topographies attached.

What concerns me is the skewed topography left eye.

Would you recommend:

1. No refractive surgery

2. PRK

3. Lasik



Atlanta, GA


Hi David

In general, if the axis of the astigmatism lines on topography/Orbscan/Pentacam up with a patient’s other refractive data, eg MR, AR, wave scans, etc, I don’t call this a skew and just attribute the pattern to the corneal topography accurately reflecting the patient’s astigmatism, which in such cases are primarily corneal in nature, rather than lenticular, for example.

I don’t work in + cylinder notation, but isn’t this the case in your case?

I’m wondering what the group’s consensus is about the use of the word “skew”? Deviating from 90/180? Or deviating from the other refractive data for cyl?

If so, then I wouldn’t be worried about anything, and I would think LASIK wouldn’t be contraindicated. She’s got plenty of tissue, manifests to 20/20, and I assume you can get old eyeglass data to confirm the degree of her astigmatism has been stable

If the Topo axis doesn’t align with her refractive axis, that in itself isn’t necessarily always that worrisome, because couldn’t she just have more lenticular than corneal cyl? But in this case I’d suggest an ASA (LASEK or epiLASEK)

The decision on whether to perform incisional vs non incisional surgery is easier for me, since as you know I’m 100% ASA

Hope you’re doing well. It’s been a long time since I’ve seen you in person–20 years!

I also have a question for you personally if you still have fellows, as I’ve got a problem situation with a current fellow I’d like your guidance on about how to deal with it

Looking forward to catching up!


Emil William Chynn, MD, FACS, MBA


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