1. Getting the Markings Right
Joja Surgicals Pvt. Ltd.

2. This presentation is issued in scientific interest to promote better marking techniques for Toric IOL implantation, LRIs and refractive surgeries
The tool and software described in this presentation are patented / copyrighted

3. This is not an advertisement

4. Why is Marking Important?
For every degree of rotation 3.3% of the effect is lost
With 30 degree rotation all effect of the Toric lens is lost
Beyond that you start adding to the astigmatism

5. Why is Marking Important?
Higher the Toric correction greater the chances of errors
e.g. For a 5 degree misalignment
In a 6 D Toric – error is 1 D
In a 1.5 D Toric – error is 0.25 D

6. So let’s get the marking spot on !
Two issues in marking
Making sure our 0 – 180 meridian is ‘true’ horizontal
Making sure that the marks bisect the cornea through the optical centre

7. Current Markers Hand held markers
With spirit level to ensure horizontality

8. Current Markers
Do not ensure that the marks pass through the centre of the cornea

9. Are you bisecting the cornea?

10. Current Markers
You also need a second intra-op mark if the placement axis is not 0 – 180

11. Current Markers Come in only one size
But the corneas are not of the same size or shape!

12. Issues
Still does not solve the problem of bisecting the cornea through the optical centre

13. A New Approach A slit lamp based system
Uses gravity to define horizontal
Uses Purkinje images to ensure centring on the cornea

14. 3 Simple Steps Set the slit lamp beam to the desired placement axis
Align the beam to pass through the corneal centre (described later)
Mark the cornea

15. Step 1 – Setting the Angle
The slit beam can be set to the axis of placement
No need for reference marking
Clamp device to chin rest of slit lamp

16. Setting the Angle

17. Step 2 Unclamp the calibrator device
Place the patient’s head normally on the slit lamp

18. Centring on the Cornea
Patient looks at the light with the other eye closed
Move the slit beam across the cornea until you get a bright Purkinje image

19. Centring on the Cornea
Images bordered in red show the correct positioning of the slit beam

20. Centring on the Cornea

21. How do we know it is accurate?

22. Planiware can be downloaded from www.suryodaya.in/planiware
This is a IOL planimetry software designed for measuring
Centration of IOL, rhexis, pupil
Measurement of rhexis / pupil areas and diameters
Angular measurements of Toric IOLs
Planiware can be downloaded from

23. Verifying your markings

24. Happy marking!