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Long-Term Results of Surface Ablation for High Myopia

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Long-Term Results of Surface Ablation for High Myopia LongLong‐‐TermTerm ResultsResults ofof SurfaceSurface AblationAblation forfor HighHigh Myopia:Myopia: thethe ImportanceImportance ofof SmoothingSmoothing FabrizioFabrizio I.I. Camesasca,Camesasca, MDMD 1 PaoloPaolo Vinciguerra,Vinciguerra, MDMD 1, 2 AdrianaAdriana Sergio,Sergio, MDMD1 IngridIngrid M.M. Torres,Torres, MDMD 1 1Istituto Clinico Humanitas 2Columbus, Ohio State University FinancialFinancial DisclosureDisclosure ••II dodo notnot havehave anyany financialfinancial interestsinterests oror relationshipsrelationships toto disclose.disclose. Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 HighHigh MyopiaMyopia MoreMore thanthan ‐‐ 6.006.00 DD (Curtin BJ, Acta Ophthalmol Suppl. 1988) •• RefractiveRefractive SurgerySurgery Risks:Risks: • Undercorrection • Haze (amount of corrected myopia ? surface irregularity ?) • Regression (induced corneal curvature gradient) • Glare • Ectasia (LASIK only) • Myopia progression • Retinal problems •• AccurateAccurate patientpatient selectionselection •• ComplexComplex treatmenttreatment •• CarefulCareful followfollow upup Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 WhyWhy SurfaceSurface AblationAblation forfor HighHigh MyopiaMyopia ?? •• HigherHigher myopicmyopic correctioncorrection possiblepossible •• LessLess biomechanicalbiomechanical effect/structuraleffect/structural instabilityinstability •• LessLess riskrisk ofof ectasiaectasia vs.vs. LASIKLASIK •• PossiblePossible betterbetter contrastcontrast sensitivitysensitivity •• TreatmentTreatment ofof eyeseyes withwith veryvery steep/flatsteep/flat corneas,corneas, widewide pupilspupils Roberts, C, J Cataract Refract Surg, Jan 2005 Langrova H, Acta Medica, Jan 2003 Shahinian L, J Cataract Refract Surg, Aug 2002 Gambato C, Ophthalmology, Feb 2005 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 PRKPRK forfor HighHigh MyopiaMyopia SurgicalSurgical TechniqueTechnique •• RetrospectiveRetrospective study:study: 20002000 ‐‐ 20062006 •• SuctionSuction ringring •• NIDEKNIDEK ECEC 50005000 excimerexcimer laserlaser •• MultipleMultiple opticaloptical zoneszones •• AblationAblation zonezone (AZ):(AZ): 4.84.8 –– 7.07.0 mmmm •• TransitionTransition zonezone (TZ):(TZ): 9.09.0 ––10.010.0 mmmm •• CrossCross‐‐cylindercylinder techniquetechnique forfor astigmatismastigmatism •• SmoothingSmoothing withwith maskingmasking fluidfluid •• MitomycinMitomycin CC (on(on selectedselected cases)cases) Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 HighHigh Myopia:Myopia: PatientPatient SelectionSelection ExclusionExclusion CriteriaCriteria General ‐ no known systemic, metabolic or collagen disease ‐ patient’s unrealistic expectations Corneal ‐ insufficient corneal thickness ‐ ectatic disease (pellucid degeneration, Mooren’s ulcer, Terrien’s degeneration) ‐ reduced endothelial cell counts Ocular ‐ increased intraocular pressure ‐ tear deficiency Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 MaterialsMaterials andand MethodsMethods •• 100100 eyeseyes,, 5959 patientspatients •• 1818 malesmales,, 4141 femalesfemales •• MeanMean ageage 34.134.1 ± 8.3 yearsyears ((rangerange:: 2121 toto 56)56) •• CornealCorneal thicknessthickness:: 560.4560.4 ± 30.1 PreoperativelyPreoperatively ((meanmean ± SD): •• VA:VA: 0.870.87 ±± 0.160.16 •• cycloplegiccycloplegic SESE :: --9.559.55 DD ±± 1.791.79 DD •• (range:(range: --7.507.50 toto --14.25)14.25) •• SphereSphere :: --8.868.86 DD ±± 1.831.83 DD ((range:range: --7.007.00 toto --14.2514.25)) •• CylCyl :: --1.391.39 DD ±± 0.900.90 DD ((range:range: --0.000.00 toto --3.75)3.75) Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 SmoothingSmoothing • Corneal regularity: more important than transparency • Irregularities: induced by ablating beam and ocular motion • Irregular curvature changes: - excessive reparative response - increased collagen deposition - haze and reduction of desired refractive effect Vinciguerra P, J Refract Surg 1998 Netto MV, Eye Res 2005 Vinciguerra P, Camesasca F, Refractive Surface Ablation, Slack 2006 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 SmoothingSmoothing • Surgical Technique: • Masking fluid (hyaluronic acid 4%), same ablation rate as normal cornea • Careful distribution with spatula •10 mm diameter ablation to avoid refractive change •10 Hz frequency to avoid overheating • Peaks will appear and be ablated Vinciguerra P, J Refract Surg 1998 Vinciguerra P, Camesasca F, Refractive Surface Ablation, Slack 2006 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 VideoVideo SmoothingSmoothing Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 ResultsResults LongLong--TermTerm FollowFollow--Up:Up: 3.13.1 ±± 1.61.6 yrsyrs (range(range 509509 –– 19201920 days)days) ••VA:VA: 0.90.9 ±± 0.200.20 ••SESE --0.450.45 DD ±± 0.830.83 DD (range(range 0.000.00 toto --2.50)2.50) ••Sphere:Sphere: --0.260.26 DD ±± 0.830.83 DD ((--2.502.50 toto +0.25)+0.25) ••CylCyl :: --0.370.37 DD ±± ±± 0.460.46 DD ((--0.000.00 toto --1.50)1.50) ••HazeHaze (0(0 toto 4+):4+): 0.110.11 ±± 0.320.32 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 SafetySafety month 100% (eyes) 90% 80% 70% 3 yrs 60% 50% 40% 29% 30% 24% 18% 20% 15% 12% 10% 1% 1% 0% lost > 2 lost 2 lost 1 unchanged gained 1 gained 2 gained > 2 EfficacyEfficacy SAFETY: Change in BSCVA - Percent 40,0 30,0 Preoperative 3 yrs 20,0 10,0 0,0 20/12 or 20/15 or 20/20 or 20/25 or 20/30 or 20/40 or 20/50 or better better better better better better better Fabrizio I. Camesasca, MD Subspecialty Day: preOPRefractive BSCVA vs. Surgery postOP UCVA 2007 - Percent RefractiveRefractive StabilityStability 2.00 0.05 -0.03 -0.10 -0.28 -0.45 0.00 01361236 -2.00 -4.00 -6.00 -8.00 -9.55 -10.00 1. STABILITY: Achieved Change in Refr. over Time HazeHaze 1.00 0.58 0.52 0.47 0.50 0.23 0.11 (Epstein D, Ophthalmology 1994) 0.00 0.00 0 1 3 6 12 36 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 IntendedIntended vs.vs. ObtainedObtained Intended correction, SE: -9.50 D ± 1.76 D Obtained correction, SE: -8.99 D ± 2.17 D 14.00 13.00 12.00 11.00 10.00 Obtained 9.00 8.00 7.00 6.00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 13.00 14.00 Intended Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 Case 1 RM, OS, 34 y.o. female -8.75 –1.50 (180) 3 years 1.0 –0.75 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 Corneal, 5 mm pupil Case 1 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 Case 2 SP, OS, 43 y.o. female -11.50 2.2 years 1.0 –0.50 –0.50 (175) Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 Corneal, 5 mm pupil Case 2 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 AberrometryAberrometry (5 mm pupil) Aberrations: Total WF Astigmatism 2,00 (RMS) 2,00 1,00 Preop. 3 yrs. 1,00 Preop. 1.08 µ 1.46 µ 3 yrs. 0.83 µ 0.52 µ 0,00 p = n.s. 0,00 p < .001 Spherical Aberration Coma 2,00 Coma 2,00 (corneal, 5 mm pupil) 1,00 Preop. 3 yrs. 1,00 Preop. 3 yrs. 0.14 µ 0.32 µ 0.21 µ 0.27 µ 0,00 p < .005 Fabrizio0,00 I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 AberrationsAberrations • Large AZ (7 – 5 mm) and TZ (10 – 8 mm) diameter minimizes postoperative spherical aberration increase • Coma (appropriate centration) increased ComplicationsComplications • Retreatments: • 2 hypercorrected eyes (2%) (same patient, 67 y.o.) • No ectasia • Corneal haze: 0.11 ± 0.32 at year 3 • No retinal detachment Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 HighHigh MyopiaMyopia •• WideWide AZ,AZ, TZ,TZ, andand multizonemultizone approachapproach createdcreated aa transitiontransition zone:zone: ••MoreMore peripheralperipheral (less(less sphericalspherical aberrationaberration)) ••MoreMore gradualgradual (less(less collagencollagen depositiondeposition andand regressionregression)) •• KnowledgeKnowledge integratedintegrated inin modernmodern customcustom ablationablation profilesprofiles •• SmoothingSmoothing createscreates aa regularregular surface,surface, decreasingdecreasing hazehaze formationformation andand regressionregression •• LongLong termterm stabilitystability eveneven withwith thinthin corneascorneas…… Nepomuceno RL, J Cataract Refract Surg, Feb 2005 Vinciguerra P, Cataract and Refractive Surg, Jan 2005 Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007 SurfaceSurface AblationAblation forfor HighHigh MyopiaMyopia ConclusionsConclusions •• TheThe mostmost happyhappy patientspatients •• HighHigh levellevel ofof accuracyaccuracy •• NoNo ectasiaectasia •• SmoothingSmoothing:: •• ModulationModulation ofof cornealcorneal healinghealing processprocess •• NoNo regressionregression •• LimitedLimited oror absentabsent hazehaze (Gambato C, Ophthalmology, 2006 Wilson, SE, Exp Eye Res, 2006) Fabrizio I. Camesasca, MD Subspecialty Day: Refractive Surgery 2007.
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