Femtosecond Laser-Assisted Astigmatic Keratotomy for Naturally Occurring Astigmatism

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Femtosecond Laser-Assisted Astigmatic Keratotomy
for Naturally Occurring Astigmatism

• Ashkan M. Abbey, BA, Takeshi Ide, MD, PhD, George
  D. Kymionis, MD, PhD, Sonia H. Yoo, MD
• Sonia H. Yoo, MD has received honoraria from AMO,
  Carl Zeiss Meditec, and Alcon.

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Purpose

• To evaluate the results of femtosecond
  laser-assisted astigmatic keratotomy (FSAK) for
  naturally occurring high astigmatism.

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Methods
?
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• Two arcuate incisions on the steepest meridians
  of the cornea were performed using an IntraLase
  femtosecond laser in a consecutive series of 9
  patients (13 eyes) with naturally occurring high
  astigmatism.

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Methods

• The femtosecond laser settings were determined
  using a modified Lindstrom nomogram.
• Age 32 to 86 years (54.46 17.50 years)
• Follow-up 5 to 13 months (Mean 9.8 months)
• A retrospective review evaluated femtosecond
  laser settings, uncorrected visual acuity (UCVA),
  best spectacle corrected visual acuity (BSCVA),
  manifest refraction, and corneal topography.

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FSAK Nomogram
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UCVA

• Improved in 12 out of 13 eyes (92.3)
• Pre-FSAK UCVA 20/25 or worse in all eyes (range
  from count fingers to 20/25)
• Latest Follow-up Post-FSAK All 13 eyes 20/60 or
  better (range from 20/60 to 20/20)

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BSCVA

• Unchanged or improved in 10 eyes (76.9)
• Pre-FSAK BSCVA 20/40 or better in all eyes
  (range from 20/40 to 20/20)
• Latest Follow-up Post-FSAK All 13 eyes 20/30 or
  better (range from 20/30 to 20/20)

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UCVA and BSCVA
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Astigmatism Change
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• Manifest cylinder decreased by more than 3 D in
  10 out of 13 eyes (76.9)
• Induced axis change was less than 30 degrees in 9
  eyes (69.2)
• Corneal cylinder decreased by more than 3.00 D in
  9 eyes (69.2)

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Doubled-Angle Plots

• Preoperative

• Postoperative

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Regression Analysis Preoperative Cylinder in
Keratoplasty Mode Eyes
R0.975, P0.001
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Conclusions

• FSAK in patients with naturally occurring high
  astigmatism appears to be a safe and effective
  technique for the reduction of astigmatism.
• The femtosecond laser is able to perform uniform
  corneal incisions with precision and a high
  degree of predictability.