SPECTRALIS® Glaucoma Module Premium Edition

1. SPECTRALIS® Glaucoma Module Premium Edition

2. Clinical Mismatch Mismatch between clinically visible disc margin & SD-OCT-based disc margin SD-OCT BMO Clinically Visible Optic Disc Margin Image Courtesy Dr. Balwantray C. Chauhan, Halifax, Canada and Dr. Claude F. Burgoyne, Portland, USA.

3. Variable Rim Tissue • Externally oblique • Internally oblique • Non-oblique BMO Clinical disc margin Image Courtesy Dr. B.C. Chauhan, Halifax, Canada. Reis et al. Ophthalmology 119:738-747,2012.

4. Clinical Disc Margin Conclusion • The clinical optic disc margin is hard to identify • In practice the clinician is looking at 3 different tissues when defining the disc margin • BMO (1), RPE tips (endings; 2), some aspect of border tissue of Elschnig (3) • The clinical disc margin is inconsistent as an anatomical landmark for the outer border of the rim • Each individual ONH can have regions of internally and / orexternally oblique border tissues

5. Overestimation of Rim Tissue Consequences • Inconsistent definition of the disc margin can mean an underestimation of rim tissue. • Using Bruch´s membrane opening (BMO)as a stable landmark provides a more accurate measurement of the ONH rim tissue. DM BMO Image Courtesy Dr. B.C. Chauhan, Halifax, Canada.

6. Invisible BMO • Bruch's Membrane Opening is a consistent landmark, butit is usually clinically and photographically invisible. BMO Image Courtesy Dr. B.C. Chauhan, Halifax, Canada.

7. Geometric Orientation • Even if BMO is used as a stable landmark by SD-OCT, we still need to measure the neuroretinal rim in the correctgeometric orientation. BMO-MRW Reis et al. Invest Ophthalmology Vis Sci. 53: 1852-1860, 2012.

8. Correct Rim Measurement • Neuroretinal rim measurementfrom BMO to nearest point on internal limiting membrane (ILM) • Shortest distance measurement • Quantification of perpendicularcross section of nerve fibers exiting the eye • Taking into account their varyingtrajectory at all 48 points of measurement BMO-MRW Basic Information Reis et al. Invest Ophthalmology Vis Sci. 53: 1852-1860, 2012. Cross Section of RNF

9. Current Reality • Current sectorial analysis is made with fixed horizontal and vertical axes on the image. AIF Horizontal (N/T) Axis AIF Vertical (S/I) Axis Acquired Image Frame (AIF)

10. Range of Variability of FoBMO Axes • Inter-individual variability in the axis connecting the Fovea and Bruch’s Membrane Opening (BMO) center < + 2° to - 18° * * Examples taken from the HDEng SPECTRALIS normative data collection

11. Anatomically Normalized Eyes • Anatomically consistent landmark in all human eyes • BMO is a true anatomic boundary of the RGC axons • BMOcentroid is the center of BMO • Fovea is the anatomic center of the retina • RGC axons organized relative to the FoBMO axis From: D. Hood et al., Glaucomatous Damage in the Macula, Prog Retin Eye Res 2013; 1-21.

12. Anatomic Positioning System - APS BMO Fovea FoBMO - Axis

13. Anatomic Positioning System - APS • Locates points in the eye using two fixed, structural landmarks • center of the foveaand • center of the Bruch’s Membrane Opening (BMO) • Automatic detection of landmarks during initial APS scan • Automatic alignment of scans relative to patient’s individual Fovea to - Bruch’s Membrane Opening (FoBMO) center axis • Consistent, accurate placement of subsequent scans and sectors for data analysis • Automatic adjustment for head tilt during acquisition

14. Anatomic Positioning System - APS Without SPECTRALIS APS • Same eye scanned on separate visits(no APS or AutoRescan) • Head tilt causes significant variability of classification results

15. Anatomic Positioning System - APS With SPECTRALIS APS • Consistent positioning foreach individual’s anatomy • Two eyes with different anatomical positions of fovea relative to the center of the BMO (A and B) • Scan orientation automatically aligned along the individual’s FoBMO axis

16. Anatomic Positioning System - APS • Accurate geometric relations between nerve fiber defects can be established,which are observed in ONH, RNFL and the Posterior Pole Asymmetry Analysis • Easy correlation between analysis methods

17. Anatomic Positioning System - APS • Consistent • Reliable Advantages • Automatic • Individual / Customized

18. SPECTRALIS Glaucoma Module Premium Edition BMO Rim Analysis

19. SPECTRALIS Glaucoma Module Premium Edition Current Sectors Garway-Heath Sectors • Advantages • Sector orientation alignedwith nerve fiber bundle trajectory • Better structure-functioncorrelation 40° 40° 110° 90° 40° 40° References: Garway-Heath DF et al. Mapping the Visual Field to the Optic Disc in Normal Tension Glaucoma Eyes. Ophthalmology 2000; 107: 1809–1815. • Same eye – different sector distribution

20. SPECTRALIS Glaucoma Module Premium Edition Current Classification New Display • Percentile: • Percentage of normal eyes have a rim this thin or thinner Actual thickness (Mean thickness value) Actual thickness (Percentile) • Remember HRT !!! • Different eyes – different displays

21. SPECTRALIS Glaucoma Module Premium Edition Externally oblique at temp. side Internally oblique at nasal side Within normal limits Borderline Outside normal limits BMO Overview

22. SPECTRALIS Glaucoma Module Premium Edition Progression

23. SPECTRALIS Glaucoma Module Premium Edition BMO Size: 1.85 mm2 BMO Size: 1.85 mm2 BMO-MRW OU Report

24. SPECTRALIS Glaucoma Module Premium Edition SPECTRALIS Glaucoma Module Premium Edition BMO-MRW & RNFL Single Eye Report