IOL Master 700 Barrett Suite TK Bandung Eye

IOL Master 700 Barrett Suite TK Bandung Eye Center Linda Periwi Product Specialist Surgical Opthalmology and Refractive Lasers

Agenda 1 Basic Biometry 2 Measurement and Analysis 3 Calculation and Formula 4 Barrett Suite 5 Lens Constant 05. 06. 2021 2

Agenda 1 Basic Biometry 2 Measurement and Analysis 3 IOL Calculation and Formula 4 Barrett Suite 5 Lens Constant 05. 06. 2021 3

Basic Biometry Contact vs Non-contact Applanation Immersion Ultrasound (sound waves) Zeiss Pte. Ltd - Jakarta Reps Office Non - contact Optical (light waves)

Basic Biometry Refractive Outcome applanation A-scan immersion A-scan partial coherence interferometry falsely short axial length easier alignment with shell non-contact laser device variable corneal compression no corneal contact phakic, pseudophakic, phakic IOLs improved consistency posterior staphaloma, silicone oil less operator dependent not limited by wavelength corneal micro-abrasions highly operator dependent or retinal thickness variations source of IOL power errors myopia hyperopia 90% 80% 70% 60% 50% 40% 30% 20% 10% -2. 0 -1. 0 0. 0 1. 0 spherical equivalent prediction error (D) -0. 5 0. 0 0. 5 Data courtesy of Warren E. Hill, MD, FACS

ZEISS Biometry Portfolio Gold standard biometry from ZEISS IOL Master 500 Latest biometry from ZEISS IOL Master 700

ZEISS Biometry Technology ZEISS IOLMaster 500 Partial Coherence Interferometry Moving Mirror ZEISS IOLMaster 700 SWEPT Source Biometry LASER Beam Infrared , 780 nm 2000 scans per second Scans in 0°, 30°, 60°, 90°, 120°, 150° Detector

Agenda 1 Basic Biometry 2 Measurement and Analysis 3 Calculation and Formula 4 Barrett Suite 5 Lens Constant 05. 06. 2021 8

Key specifications SWEPT Source Biometry Scan depth: Scan width: Fixation check width: Resolution in tissue: Speed: 44 mm 6 mm ~1 mm (on retina) 22 µm 2, 000 scans/s Standard Deviation of Repeatability Central cornel thickness Anterior chamber depth Lens thickness Axial length measurement Keratometry (SE) ± 2 µm ± 10 µm ± 19 µm ± 0. 07 D

IOL Master 700 Measurements Axial Length Keratometry Anterior Chamber Depth Lens Thickness Central Corneal Thickness White-to-white Pupillometry

IOL Master 700 Analyze SWEPT Source Biometry® facilitates a Full-Length OCT Scan for visually verifying measurements and detecting unusual eye geometries Fixation Check Telecentric Keratometry 3 Zones Fixation Check and Telecentric Keratometry for robust measurements

IOL Master 700 Cases Carl Zeiss Meditec, Klaus Lassak, Application March 2012 12

IOL Master 700 Cases Carl Zeiss Meditec, Klaus Lassak, Application March 2012 13

Get fewer refractive surprises Fixation Check for more accurate measurements See the foveal pit? Good fixation! No foveal pit visible! Poor fixation!

Example: More accurate & repeatable measurements Measurement 1 Good fixation! See the foveal pit? ! Measurement 2

Example: More accurate & repeatable measurements Measurement 1 Only 10 µm difference in axial length Measurement 2

Example: More accurate & repeatable measurements Measurement 1 Only 0. 02 D difference in keratometry Measurement 2

Example: Influence on K-values

Example: helps to identify measurement errors Measurement 1 Poor fixation! No foveal pit visible! Measurement 2

Example: helps to identify measurement errors Measurement 1 190 µm difference in axial length! Measurement 2

Example: helps to identify measurement errors Measurement 1 >0. 5 D difference in keratometry! Measurement 2

Example: Influence on K-values

Improve your refractive outcomes Telecentric keratometry for more robust measurements

Distance-dependent keratometry measures in different zones of the cornea

Measurement Axial Length Zeiss Pte. Ltd - Jakarta Reps Office

Measurement Keratometry • Measures the curvature and thus the refractive power of the cornea • Indicates the presence and location of astigmatism The horizontal (K 1) and vertical (K 2) curvatures are measured then averaged (i. e. K 1 = 43. 00 D K 2 = 44. 00 D Average K = 43. 50 D Zeiss Pte. Ltd - Jakarta Reps Office • Expressed in diopters (D) or radius of curvature in millimeters (mm) with the average value being 43. 50 D or 7. 76 mm

Analyze Keratometry “ Another metric on the IOL Master that you may not have looked at is the standard deviation of the keratometry (K). “ “ If that value greater than 0. 20 D, the patient has irregular astigmatism and is going to have a refractive surprise because the K readings are wrong. Get a topography reading ” Jack Holladay on Hidden Figures; Dig deeper into your measurements to get more predictable refractive results and happier patients. Zeiss Pte. Ltd - Jakarta Reps Office

Measurement Anterior Chamber Depth (ACD) • To predict Effective Lens Position (ELP) • ELP is the position where IOL will “stands” after surgery. Converted into Aconstant on every specific IOL Anterior cornea (epithelium) to front surface of lens Zeiss Pte. Ltd - Jakarta Reps Office

Measurement White to white (WTW) and Pupil (P) Measurement including • Iris diameter (WTW) o Angle alpha: centre of limbus – centre of visual axis (Ix, Iy) • Pupil diameter (P) o Angle kappa: centre of pupil – visual axis (Px, Py) Zeiss Pte. Ltd - Jakarta Reps Office

Angle Alpha – Angle Kappa Angle alpha • Angle alpha is the difference between the center of the limbus and the visual axis. Zeiss Pte. Ltd - Jakarta Reps Office Angle kappa (CW-Chord) • Angle kappa is the difference between the center of the pupil and the visual axis.

Anggle Kapa - CWC = 0, 5 mm @ 101° Py = + 0, 5 mm Px = -0, 1 mm Zeiss Pte. Ltd - Jakarta Reps Office

Anggle Kappa - CWC • Jack Holladay – „Pay attention to the Angla Kappa!“ • The dimension between the visual axis and the pupil is called the angla kappa (or chord mu / CWC). • The proper place to center a diffractive, premium aspheric, or toric IOL is halfway between the visual axis and the center of the pupil. • If that value is greater than 0. 6 mm, patients with diffractive lenses will have halos and glare. Zeiss Pte. Ltd - Jakarta Reps Office

Agenda 1 Basic Biometry 2 Measurement and Analysis 3 Calculation and Formula 4 Barrett Suite 5 Total Keratometry 05. 06. 2021 33

IOL Calculation and Formula 1 st and 2 nd Generation SRK Formula P = A – 0. 9 K – 2. 5 AL P = IOL Power A = lens constant K = keratometry AL = axial length Keratometry – 1 D error = 1 D refractive error Axial Length – 1 mm error = 3 D refractive error!! Zeiss Pte. Ltd - Jakarta Reps Office

IOL Calculation and Formula 3 rd Generation Assumption of ACD based on measured K Holladay I (1988) SRK/T (1990) Hoffer. Q (1993) Surgeon Factor A-constant personalized ACD (p. ACD) Zeiss Pte. Ltd - Jakarta Reps Office

IOL Calculation and Formula 4 th Generation Measured ACD Haigis Holladay II a 0, a 1, and a 2 optimized wider range ACD wider range Zeiss Pte. Ltd - Jakarta Reps Office

IOL Calculation and Formula New Generation toric IOL, post-Lasik patient Barrett Formula Take posterior cornea into consideration, derived from nomogram which Prof. Barrett developed himself Require LF DF. Barrett Universal II: normal Barrett Toric: for toric IOL Barrett True-K: post-Lasik eye Zeiss Pte. Ltd - Jakarta Reps Office Haigis Suite Formula Haigis: normal Haigis-T: for toric IOL Haigis-L: post-Lasik eye Haigis-TL : post-Lasik eye using toric IOL

IOL Calculation and Formula Calculated Pamareters Axial Length Holladay 1 Hoffer Q SRK/T Haigis Holladay 2* Barret K's ACD WTW LT LF DF

IOL Calculation and Formula Based on Axial Length Formula performance for outcomes within ± 0. 50 D of target refraction Extreme Short Normal Extreme Long Holladay 1 Hoffer Q SRK/T a 0, a 1, a 2 optimized Haigis Suite a 0 optimized a 0, a 1, a 2 optimized Holladay II Barrett Suite Axial Length <17 19 of 20 21 E. 22 23 FACS 24 25 26 27 28 data 18 courtesy Warren Hill, MD, 29 30 31 32 33 >34

Agenda 1 Basic Biometry 2 Measurement and Analysis 3 Calculation and Formula 4 Barrett Suite 5 Lens Constant 05. 06. 2021 40

ZEISS IOLMaster 700 Barrett Suite 05. 06. 2021 41

ZEISS IOLMaster 700 Barrett Suite Barrett Formulas • New Generation Formulas • The Barrett formulas use a theoretical model eye in which anterior chamber depth (ACD) is related to axial length and keratometry. • Thick lens formula that can optionally take into account the change in principle planes encountered with IOLs of different powers. • Barrett Toric formula for toric IOL theoretically takes into account posterior surface of the cornea (no actual measurement, based on nomogram) https: //theophthalmologist. com/powerlist/2016/graham-barrett/ 05. 06. 2021 42

ZEISS IOLMaster 700 Barrett Suite Barrett Formulas • New Generation Formulas • It has the option to utilize up to 5 variables consisting of AL, Ks, ACD (optional), LT (optional) and WTW (optional). • The Lens Factor (LF) used in all Barrett formulas is the equivalent to other constants used in standard IOL power calculation formulas. It is derived from the SRK/T formula’s constant, using a formula established and verified by Dr. Barrett himself. • A Design Factor (DF) is not subject to optimization but is characterized by the design of one specific IOL. DFs are therefore fixed values. The DF can only be defined by the respective IOL’s manufacturer with detailed knowledge of the respective IOL’s design. • Barrett Toric formula also makes adjustments for WTR and ATR astigmatism. 05. 06. 2021 43

ZEISS IOLMaster 700 Barrett Suite Barrett Toric Formula • Posterior corneal curvature • Other formulas assume that the posterior corneal curvature and the anterior curvature have a constant ratio. • However, there is vertical steepening of the posterior cornea of ~0. 3 D (i. e. ATR astigmatism). • Posterior cornea acts like a negative lens. • The Barrett Toric formula corrects for nonconstant ant-post ratio via a nomogram. ATR Astigmatism WTR Astigmatism https: //www. aao. org/eyenet/article/toric-iol-calculations-consider-posterior-cornea 05. 06. 2021 44

ZEISS IOLMaster 700 Barrett Suite Barrett Toric Formula • Posterior corneal curvature • Has not been accounted for in many other toric lens calculations… “Ignoring posterior corneal astigmatism may yield incorrect estimation of total corneal astigmatism” “Selecting toric intraocular lenses based on anterior corneal measurements could lead to overcorrection in eyes that have with-the-rule astigmatism and undercorrection in eyes that have against-the-rule astigmatism. ” Prof. Graham Barrett 05. 06. 2021 45

Agenda 1 Basic Biometry 2 Measurement and Analysis 3 Calculation and Formula 4 Barrett Suite 5 Lens Constant 05. 06. 2021 46

IOL Calculation and Formula User Group for Laser Interference Biometry (ULIB) Zeiss Pte. Ltd - Jakarta Reps Office

Improve your refractive outcomes ULIB compatibility 1 Aristodemou P, Knox Cartwright NE, Sparrow JM, Johnston RL, Intraocular lens formula constant optimization and partial coherence interferometry biometry: Refractive outcomes in 8108 eyes after cataract surgery, J Cataract Refract Surg. 2011 Jan; 37(1): 50 -62

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