1. Typical Allegretto Ablation Profiles
NOTE: Images show ablation depths, not corneal shapes
Joachim Loeffler
New Wave Consulting GmbH

2. New Wave Consulting GmbH
Myopic Pure Sphere 2D
Joachim Loeffler
New Wave Consulting GmbH

3. New Wave Consulting GmbH
Myopic Pure Cylinder
Joachim Loeffler
New Wave Consulting GmbH

4. New Wave Consulting GmbH
Hyperopic Pure Sphere
Joachim Loeffler
New Wave Consulting GmbH

5. Hyperopic Pure Cylinder
Joachim Loeffler
New Wave Consulting GmbH

6. Maximum Ablation Depths
Hyperopic Sphere:
max.µm all around periphery (0 µm in center)
Hyperopic Cylinder:
max.µm in periphery at MINUS-Cyl-Axis (0 µm in center)
Myopic Sphere:
max. µm µm in center (0 µm all around periphery)
Myopic Cylinder:
max. µm in periphery at MINUS-Cyl-Axis
max. µm in center (0 µm in periphery at 90° apart Minus Cylinder Axis)
Joachim Loeffler
New Wave Consulting GmbH

7. New Wave Consulting GmbH
Remarks
Same amount of tissue/diopter is taken for spheres and cylinders, no matter if hyperopic or myopic profile
Lets assume for the following examples our laser would take 10µm / diopter at a certain optical zone.
How much tissue will different ablation pattern combinations take?
Joachim Loeffler
New Wave Consulting GmbH

8. Treatment / Correction Options
Example Mixed Astigmatism: -2 / +3 x 0° equals / -3 x 90°
Different treatment options:
A) Plus Cylinder Sphere: -2 Cylinder: +3 x 0°
B) Minus Cylinder Sphere: +1 Cylinder: - 3 x 90°
C) Crossed Cylinder Cylinder1: -2 x 90° Cylinder2: +1 x 0°
D) Split Cylinder Sphere: Cylinder1: +1.5 x 0° Cylinder2: x 90°
E) Any other split cylinder …..
All options create the same refractive change and the same resulting K‘s
Joachim Loeffler
New Wave Consulting GmbH

9. New Wave Consulting GmbH
Ablation Depths
Treatment Profiles
central 0°
90°
Plus Cylinder
Sphere
Cylinder +3 x 0°
total
20µm
0µm
30µm
Minus Cylinder
Sphere +1
Cylinder -3 x 90°
Total
10µm
40µm
Crossed Cylinder
Cylinder1 -2 x 90°
Cylinder2 +1 x 0°
Split Cylinder
Sphere
Cylinder x 90°
Cylinder x 0°
5µm
15µm
Joachim Loeffler
New Wave Consulting GmbH

10. New Wave Consulting GmbH
Question
What are the concerns with PLUS CYLIDER?
Joachim Loeffler
New Wave Consulting GmbH