Joja Surgicals Pvt. Ltd.www.jojasurgical.comjojasurgical@gmail.com

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

This is not an advertisement

Why is Marking Important?For every degree of rotation 3.3% of the effect is lostWith 30 degree rotation all effect of the Toric lens is lostBeyond that you start adding to the astigmatism

Why is Marking Important?Higher the Toric correction greater the chances of errorse.g. For a 5 degree misalignmentIn a 6 D Toric error is 1 DIn a 1.5 D Toric error is 0.25 D

So lets get the marking spot on !Two issues in markingMaking sure our 0 180 meridian is true horizontalMaking sure that the marks bisect the cornea through the optical centre

Current MarkersHand held markersWith spirit level to ensure horizontality

Current MarkersDo not ensure that the marks pass through the centre of the cornea

Are you bisecting the cornea?

Current MarkersYou also need a second intra-op mark if the placement axis is not 0 180

Current MarkersCome in only one sizeBut the corneas are not of the same size or shape!

IssuesStill does not solve the problem of bisecting the cornea through the optical centre

A New ApproachA slit lamp based systemUses gravity to define horizontalUses Purkinje images to ensure centring on the cornea

3 Simple StepsSet the slit lamp beam to the desired placement axisAlign the beam to pass through the corneal centre (described later)Mark the cornea

Step 1 Setting the AngleThe slit beam can be set to the axis of placementNo need for reference markingClamp device to chin rest of slit lamp

Setting the Angle

Step 2Unclamp the calibrator devicePlace the patients head normally on the slit lamp

Centring on the CorneaPatient looks at the light with the other eye closedMove the slit beam across the cornea until you get a bright Purkinje image

Centring on the CorneaImages bordered in red show the correct positioning of the slit beam

Centring on the Cornea

How do we know it is accurate?

Planiware 2.0This is a IOL planimetry software designed for measuringCentration of IOL, rhexis, pupilMeasurement of rhexis / pupil areas and diametersAngular measurements of Toric IOLs

Planiware can be downloaded from www.suryodaya.in/planiware

Verifying your markings

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