Purpose:
To report a case of spectacle-free reading in presbyopic patient post Broad Beam laser operation.
(Superficial PRK).
Methods:
A 46 year old man, who had his left eye operated on using superficial PRK 5 years ago, in 2005.
His right eye has not been operated on and he has continued to use the same power contact lens.
Use of the Profile 500 created by the Fyodrov Institute for the superficial PRK. Keratotopography TMS-ⅡN and other routine exams pre and post refractive surgery.
Picture A: Broad Beam laser (superficial PRK)
Results:
Pre operative data for the left eye SE -6.00D / BCVA 1.2 / UCVA 0.03 in distance.
- Post operative data at 5 years, for the left eye: SE -0.5D / BCVA 1.2 / UCVA 0.9 in distance. Near vision 0.5 at 40 cm.
- The un-operated right eye using a contact lens -5.00D / BCVA 1.2 / UCVA 0.05 in distance. Now, near vision with contact lens is 0.3 and without contact lens 0.7 at 40 cm.
- The keratotopogram of the left eye shows the three post operative corneal zones:
- Central zone: mostly blue color indicating a less refractive power zone.
- Para central zone: light green ring indicating a small refractive power zone.
- Peripheral zone: yellow to reddish ring indicating a high refractive power zone.
Broad Beam Laser:
Comparative to superficial PRK but a non scanning laser.
Plus points:
- Create a multifocal refractive surface.
- Less risk of infection.
- Less risk of irregular astigmatism.
- Less risk of keratectasia.
Picture B: Keratotopogram of the patient left eye
Conclusions:
Post operated left eye using superficial PRK was successful with both near and far vision.
This finding leads me to hypothesize that I have created an aspheric refractive multifocal corneal surface similar to a multifocal refractive IOL.
Points to consider:
1.Broad Beam Laser using one very powerful , solid multi intensity laser which creates a kind of photochemical vaporization.
2.Multifocal abrasion via smooth laser energy distribution to create a multifocal refractive surface.
3.Transepitherial superficial PRK is a One Step operation combining both the epitherial and stromal mode.
4.Flapless operation gives me the ability to use the greater (diameter and depth) refractive corneal surface to maximize the patients potential multifocal refractive surface.
