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Instituto Oftalmológico Hoyos Barcelona - SPAIN. IOL POWER CALCULATION POST-REFRACTIVE SURGERY. JAIRO E. HOYOS, MD MELANIA CIGALES, MD. THE PROBLEM. CORNEAL POWER POST-REFRACTIVE SURGERY. J Hoyos. CORNEAL POWER. THE TOPOGRAPHY OVER-ESTIMATES CORNEAL POWER AFTER CORNEAL
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Instituto Oftalmológico Hoyos Barcelona - SPAIN IOL POWER CALCULATION POST-REFRACTIVE SURGERY JAIRO E. HOYOS, MD MELANIA CIGALES, MD
THE PROBLEM CORNEAL POWER POST-REFRACTIVE SURGERY J Hoyos
CORNEAL POWER • THE TOPOGRAPHY OVER-ESTIMATES CORNEAL POWER AFTER CORNEAL REFRACTIVE SURGERY UNDERCORRECTION IOL CALCULATION RESULT = HYPEROPIA J Hoyos
METHODS TO CALCULATE CORNEAL POWER POST-REFRACTIVE SURGERY CORNEAL POWER 1- HOLLADAY REFRACTIVE HISTORY 2- HARD CONTACT LENS 3- CORNEAL TOPOGRAPHY 4- KERATOMETRY J Hoyos
KMSG HOT LINE IOL CALCULATION POST-RS kmsg@intercom.es J Hoyos
PRE-OP KERATOMETRY OBTAINED CORRECTION (Corneal Plane) KMSG HOT LINE CORNEAL POWER POST-R.S. CORNEAL POWER TO CALCULATE CORNEAL CURVATURE “HOLLADAY REFRACTIVE HISTORY METHOD” J Hoyos
KMSG HOT LINE CALCULATION FORMULA • SRK-T(>26 mm) • Holladay(24.5 – 26 mm) • Hoffer Q (>22 mm) J Hoyos
IS IMPORTANT TO HAVE THE PREOPERATIVE AXIAL LENGTH KMSG HOT LINE AXIAL LENGHT • AXIAL LENGTH CAN INCREASE DUE TO A GLOBE INGROWTH. • POST-LASIK CENTRAL CORNEA IS THINNER = BIOMETRY ERROR: INDENTATION USING APPLANATION [IMMERSION BEST] J Hoyos
CLINICAL CASE POST-LASIK : Refraction: -0.50 Sim K (32.7 x 32.3) PRE-LASIK: (40 years) Refraction: -16 - 4 x 170º Sim K: (46.3 x 42.4) Axial length : 31.9 mm 3 YEARS POST-LASIK: CATARACTS J Hoyos
-14.75 (-0.5) CORNEAL POWER “CLINICAL HISTORY METHOD” 1- Pre-LASIK REFRACTION : -16 - 4 x 170 Spherical equivalent : -18 In the corneal plane: -14.75 2- Post-LASIK REFRACTION : -0.50 3- CORNEAL PLANE CORRECTION : = -14.25 - J Hoyos
44.35 14.25 CORNEAL POWER “CLINICAL HISTORY METHOD” 3- CORNEAL PLANE CORRECTION :-14.25 4- Pre-LASIK KERATOMETRY : 42.4 x 46.3 Mean Keratometry: 44.35 5- Post-LASIK CORNEAL POWER : = 30.10 - J Hoyos
POST-LASIK TCC: Sim K = 32.5 Central K= 30.6 CALCULATED = 30.1 CORNEAL POWER J Hoyos
PRE-LASIK: Refraction: -16 - 4 x 170º Axial length: 31.9 mm POST-LASIK (3 years): Cataract Axial length: 31.06 mm 31.9 mm AXIAL LENGTH = AXIAL LENGHT J Hoyos
RESULT • CORNEAL POWER = 30.1 D • AXIAL LENGTH = 31.9 mm • FORMULA CALCULATION = SRK/T Predict refraction -0.74 Final refraction 0.00 IOL CALCULATION ACRYSOF (MA60BM) A const 118.80: +16.5 J Hoyos
Pre-OP Post-OP -16.5 -2.75 -18 -2 -18.5 -2.75 Post-KM in situ -21 -3.5 7 Cases -21.25 -2.5 CATARACTS -8.25 -1 -9 -2 Post-LASIK -18 -0.5 1 Case PERSONAL EXPERIENCE J Hoyos
37.6 37 36.5 33.6 30.35 29.8 35.9 30.25 31.3 33.85 30 30.4 35 32.63 31.9 32.5 30.1 30.3 37.05 30.37 31.5 37.85 37 36.5 PERSONAL EXPERIENCE CORNEAL POWER Sim-K 35.41 ± 2.00 K-Calculated 32.21 ± 3.07 Central-K 32.27 ± 2.69 TCC Refractive History TCC J Hoyos
+19 -1 0 +17.5 -0.55 -1 +16.5 -0.75 0 +18.5 -1 -2 +15.0 -1.25 -1 +17 0 +1.5 +15 -0.62 0 +16.5 -1 0 PERSONAL EXPERIENCE S R K / T RESULTS Desired refraction -0.75 ± 0.38 Obtained refraction -0.31 ± 1.03 IOL POWER 16.87 ± 1.45 J Hoyos
1-CORNEAL CURVATURE CALCULATION Clinical History Method (If Unknown, use flattest K) 2-FORMULA CALCULATION : SRK/T 3-POSSIBILITY OF INDENTATION BIOMETRIC ERROR CONCLUSIONS J Hoyos
PRE-REFRACTIVE SURGERY DATES Patient___________________________ Surgery______________Date_________ Refraction: OD_____________________ OS _____________________ Keratometry: OD__________________ OS __________________ Axial Length: OD__________________ OS___________________ RECOMENDATION J Hoyos
THANK YOU J Hoyos