Managing the Managing the Refractive “Surprise” Refractive “Surprise”

After Toric IOL PlacementAfter Toric IOL Placement Brad H Feldman, Brad H Feldman,

MDMDDerek DelMonte, Derek DelMonte,

MDMDAlan N Carlson, Alan N Carlson,

MDMD

Authors have no financial interests

Duke Eye Duke Eye CenterCenter

Durham, NCDurham, NC

Case PresentationCase Presentation53 year-old man referred to the Duke Eye 53 year-old man referred to the Duke Eye Center for 2nd opinion regarding residual Center for 2nd opinion regarding residual astigmatism after undergoing cataract astigmatism after undergoing cataract extraction with Toric IOL left eyeextraction with Toric IOL left eye

Patient originally chose Toric IOL on Patient originally chose Toric IOL on surgeon recommendation to achieve surgeon recommendation to achieve astigmatic neutrality and decrease astigmatic neutrality and decrease spectacle dependencespectacle dependence

Patient completely unsatisfied with Patient completely unsatisfied with outcome immediately after surgeryoutcome immediately after surgery

Surgeon indicated there was nothing more Surgeon indicated there was nothing more he could offer the patienthe could offer the patient

Prior Ocular HistoryPrior Ocular History

Note: patient underwent myopic Note: patient underwent myopic LASIK OU in 1999 with monovision LASIK OU in 1999 with monovision OSOS– Pre-LASIK OS MRx: -6.75 +1.25 x 080Pre-LASIK OS MRx: -6.75 +1.25 x 080– Post-LASIK OS MRx: -1.50 spherePost-LASIK OS MRx: -1.50 sphere

Cataract noted in August 2007 with Cataract noted in August 2007 with BCVA of 20/50 OSBCVA of 20/50 OS– OS MRx: -3.00 –1.25 x 170OS MRx: -3.00 –1.25 x 170

Prior History ContinuedPrior History ContinuedPre-Cataract Surgery Evaluation OS Pre-Cataract Surgery Evaluation OS

April 2008 (Still at Outside Facility)April 2008 (Still at Outside Facility)

– MRx: -2.75 -1.00 x 170 MRx: -2.75 -1.00 x 170 BCVA: 20/60BCVA: 20/60

– Orbscan Keratometry: Orbscan Keratometry: 42.90/43.70 x 098 42.90/43.70 x 098

+ 0.8D x 098+ 0.8D x 098

– IOL Master K Values: IOL Master K Values: 42.13/43.21 x 092 42.13/43.21 x 092

+1.1D x 092+1.1D x 092

– Manual KeratometryManual Keratometry 40.20/42.20 x 09840.20/42.20 x 098

+2.0D x 098+2.0D x 098– US PachymetryUS Pachymetry 479 microns479 microns

IOL Calculations: (Outside IOL Calculations: (Outside Facility)Facility)

Patient chose Toric “Premium” Patient chose Toric “Premium” LensLensLens Power:Lens Power:– IOL Master DerivedIOL Master Derived– SRK/T Clinical History MethodSRK/T Clinical History Method

Astigmatism Power:Astigmatism Power:– Alcon AcrySof Toric Calculator UsedAlcon AcrySof Toric Calculator Used– Based on Manual K’s Based on Manual K’s

As per instructions of online calculatorAs per instructions of online calculatorNote difference in Note difference in powerpower of K axes of K axes between Orbscan, IOL Master, and between Orbscan, IOL Master, and Manual K’s (see prior slide)Manual K’s (see prior slide)

IOL IOL CalculationCalculation

ss

Postoperative CoursePostoperative CourseUCVAUCVA 20/60; plano –2.50 x 100 = 20/60; plano –2.50 x 100 = 20/2020/20ExaminationExamination– Axis flipped despite properly achieving the Axis flipped despite properly achieving the

intended axisintended axis– Position: asymmetric fixation, superior loop in Position: asymmetric fixation, superior loop in

sulcus, inferior loop in bag, optic decentered sulcus, inferior loop in bag, optic decentered superiorly and tiltedsuperiorly and tilted

Assessment:Assessment:– Pantoscopic tilt with optic decentration Pantoscopic tilt with optic decentration

making astigmatic correction by the IOL making astigmatic correction by the IOL overly effective, causing over correction and overly effective, causing over correction and axis flipaxis flip

Plan:Plan: Reposition lens for symmetric bag Reposition lens for symmetric bag fixationfixation– Please view attached video for detailsPlease view attached video for details

Post-Repositioning CoursePost-Repositioning Course

UCVAUCVA 20/6020/60

MRx:MRx: +0.75 –2.75 x 100 = 20/20+0.75 –2.75 x 100 = 20/20

ExaminationExamination– Reveals correct Toric IOL position, centration, Reveals correct Toric IOL position, centration,

& axis& axis– Atlas Topography:Atlas Topography: 42.50/42.62 x 09042.50/42.62 x 090

+0.12 x 090+0.12 x 090– Pentacam Holladay Equivalent Ks Pentacam Holladay Equivalent Ks (4.5mm zone):(4.5mm zone):

42.00/42.90 x 11042.00/42.90 x 110

+0.90 x 110+0.90 x 110

Post-Repositioning CoursePost-Repositioning Course

Our initial assessment in consultation Our initial assessment in consultation supported an improperly implanted IOL as supported an improperly implanted IOL as the culprit for the astigmatic axis flip.the culprit for the astigmatic axis flip.

The patient’s outcome after his second The patient’s outcome after his second surgery indicates the original IOL selection surgery indicates the original IOL selection error was based on using a post-LASIK error was based on using a post-LASIK manual “K” reading. Additional data manual “K” reading. Additional data revealed this was inconsistent with other revealed this was inconsistent with other astigmatism measurements.astigmatism measurements.

Patient remains frustrated and is now Patient remains frustrated and is now contemplating IOL exchange.contemplating IOL exchange.

DiscussionDiscussion

The differential diagnosis for a “surprise” The differential diagnosis for a “surprise” result after surgery includes:result after surgery includes:– Wrong astigmatic power calculation and IOL Wrong astigmatic power calculation and IOL

selectionselection– Incorrect astigmatic axis alignmentIncorrect astigmatic axis alignment– Incorrect Toric IOL location resulting from Incorrect Toric IOL location resulting from

decentration or optic tiltdecentration or optic tilt– Surgical or postoperative induction of Surgical or postoperative induction of

astigmatism related to wound healing or IOL astigmatism related to wound healing or IOL optic rotationoptic rotation

SummarySummary53 yo h/o LASIK unsatisfied due to astigmatism 53 yo h/o LASIK unsatisfied due to astigmatism following cataract surgery with Toric IOLfollowing cataract surgery with Toric IOL– Toric IOL was selected on the basis of manual “K” Toric IOL was selected on the basis of manual “K”

readings as recommended by IOL selection protocolreadings as recommended by IOL selection protocol– Original measurements were inconsistent:Original measurements were inconsistent:

IOL Master ≠ Orbscan ≠ Pentacam ≠ Manual “K”’s IOL Master ≠ Orbscan ≠ Pentacam ≠ Manual “K”’s

Our error was attributing the initial surgical outcome entirely to faulty IOL fixation and position– There was optic tilt and decentration secondary to There was optic tilt and decentration secondary to

asymmetric capsular fixation from the original surgeryasymmetric capsular fixation from the original surgery

Astigmatism remained despite proper Astigmatism remained despite proper repositioning repositioning – This suggests the original surgeon used manual “K” This suggests the original surgeon used manual “K”

readings which were incorrect after previous LASIK readings which were incorrect after previous LASIK surgerysurgery

ConclusionConclusion

Measuring corneal astigmatism after Measuring corneal astigmatism after refractive surgery requires multiple methods refractive surgery requires multiple methods and more critical analysis for consistency and more critical analysis for consistency before recommending astigmatism-before recommending astigmatism-correcting Toric IOLs.correcting Toric IOLs.

Critical analysis and caution are warranted Critical analysis and caution are warranted when considering a Toric IOL in cases having when considering a Toric IOL in cases having discrepancies between different methods of discrepancies between different methods of “K” readings“K” readings