Use Of Ptk To Treat Advanced Type Ii Corneal Dystrophy (Avellino)

To present a case of a 45-year-old female with corneal dystrophy type II (Avellino) with extremely deep and large inclusions. The patient received PTK with MMC to reduce the number of inclusions in the center of her visual axis. Her UCVA improved from 20/45 to 20/30 after a 60 second treatment for both eyes.

University Eye Hospital Svjetlost, Zagreb, Croatia

A female patient 45 years of age suffers from bilateral corneal dystrophy type II, she was advised by doctors in Belgrade, Serbia her only option for better visual acuity would be a full thickness corneal transplant. She arrived at our center for a second opinion. During the exam we found she had large inclusions going as deep as 300 microns and with some central inclusions measuring over 500 microns in both eyes. As she was accompanied by her family we performed anterior segment OCT on two of her children a girl, 9 years and boy, 11 years. The boy's cornea already has inclusions, but they are still not visually significant. After counseling and evaluation we agreed to perform PTK with target depths of 180 microns. We explained to the patient that this would be a level safe enough for her corneal biomechanics but remove about 70% of the visual significant inclusions. PTK was performed in 4 steps for each eye, first step was 90 microns, the subsequent 3 steps were 50 micron, 20 microns, 10 microns with BSS used as masking fluid between steps to ensure maximal smoothens of corneal stromal bed after surgery. We used a large 9 mm zone for the PTK on Schwind Amaris 1050RS to minimize the risk of refractive shift during the PTK. After 3 weeks the patient recovered, her UCVA increased from 20/45 to 20/30 with her reporting substantially more color and light entering her eyes. 

PTK can be a great option for treatment of corneal dystrophies even when their depth is more than you can safely treat, the goal doesn’t have to be 20/20 it just needs to be better than what the patient has now, as the alternative of a corneal graft is a significantly riskier procedure with less predictable long-term outcomes.