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PRK for corneal scars

Dr. Chynn wrote in bold to a question from another doctor:


Tangent from the December discussion on PTK in corneal scarring:

I have a 24yo with history of traumatic recurrent erosion in the left eye. Had anterior micropuncture performed by another surgeon this past December but has started to re-erode. He wants to have PTK/EpiLASIK to reduce erosions and dependence on glasses. Has been in soft bcl changed q2weeks x 2 months.

His ASP is in a cluster at 6 o’clock paracentral – just outside the visual axis. 

Historical refractions in that eye (OS) are: 

2008: -5.00-0.50×153

2010: -5.25-0.50×153

2014: -6.75-0.50×70 (this is after erosion; before ASP)

This seems like an outlier so I’d ignore it

Current MRX OS:

-5.25 – 0.75 x 115 (1 week out of SCL)

-5.75 – 0.50 x 90   (2 weeks out of scl)

You must ALWAYS also do a wet MR or AR to check for accommodation in young pts

Current CRX OS:

5.25 -1.00 x 120 (1 week out of scl)

Any advice on refractive target here and how to adjust for age and epithelial healing in area of asp?

Topo currently shows steepening over that area.

Need to send us images to r/o other abnormalities

Planning to use MMC per treatment nomogram and h/o prior corneal surgery.

The pt is clearly progressing his myopia

Get older Rxs for better data on progression

What’s his profession?

Will need to overshoot for this reason

A few ASPs aren’t going to affect anything

Agree safer to use MMC

Why is one out of BCL x only 1 wk?

Might as well wait another week

Let us know the other data pls

Thank you,


Fayetteville AR

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