Dedicated Software for Bifurcation QCA: Pie Medical (CAAS 5.9) and MEDIS (QAngio XA ) Validation on Phantom analysis

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1 6 th European Bifurcation Club October 2010 BUDAPEST Imaging session 22/10/10 18:10-18:25 Dedicated Software for Bifurcation QCA: Pie Medical (CAAS 5.9) and MEDIS (QAngio XA ) Validation on Phantom analysis Chrysafios Girasis, MD Patrick W. Serruys, MD PhD Erasmus MC, Rotterdam Cardialysis B.V., Rotterdam Cardiovascular Research Foundation, New York

2 Dr. Chrysafios Girasis Prof. Dr. P.W. Serruys do not have any potential conflict of interest

3 Need for validation What we all agree: QCA software needs to be standardised with appropriate algorithms allowing multiple segment of interest analysis. V.Legrand, EuroIntervention 2007;3(1):44-49 The setting up of a large database allowing the identification of the most efficient techniques for each lesion type requires...guidelines for QCA of bifurcation lesions. Y.Louvard, Catheter Cardiovasc Interv 2008;71(2): Current angiographic analysis softwares have overcome many of these challenges, and validations of these systems will prove essential in reliably establishing their role in clinical application and research. A.Lansky, Catheter Cardiovasc Interv 2009;73(2):258-66

4 CAAS D bifurcation QCA software Bifurcation 11-segment model (BSM11) Bifurcation 6-segment model (BSM6) S.Ramcharitar, EuroIntervention 2008;3(5):553-7 C.Girasis, Catheter Cardiovasc Interv 2010 (accepted) QAngio XA T-shape analysis Y-shape analysis Absolute or relative analysis A.Lansky, Catheter Cardiovasc Interv 2009;73(2):258-66

5 Medis solution for reference contours Use a proprietary algorithm to create reference contours of the bifurcation core Assumes carinal point is not diseased: Both arterial and reference contours go through the carina point

6 QAngio XA-models T-shape model Y-shape model 3 diameter functions: - One for proximal branch inc. bifurcation core - One for each distal branch Two diameter functions: - One for the side branch - One for the main branch showing two obstructions

7 CAAS 5-Definition of POB Largest circle that fits in bifurcation and touches all three contours The tentative point of bifurcation is relocated at the center of the circle. Point of bifurcation (POB)

8 CAAS 5-Definition of POB Largest circle that fits in bifurcation and touches all three contours The tentative point of bifurcation is relocated at the center of the circle. Point of bifurcation (POB)

9 CAAS 5-Definition of POC The boundaries of the Polygon of Confluence are defined at the intersects between the circle and the 3 center lines. Polygon of confluence (POC) Start of bifurcation End of bifurcation

10 CAAS 5-Diameter in POC Around the point of bifurcation, the shortest distance to the vessel wall is suddenly no longer in the main vessel, but jumps to the distal end of the side branch

11 CAAS 5-Diameter in POC

12 Dedicated algorithm for calculation of bifurcation angle (BA) in CAAS 5 Inflow and outflow directions at the ostia of the POC SOB EOB Angle distal main side branch Angle prox main side branch

13 Computer guided production of bifurcation phantoms Quantitated 3D design (cad: computer aided design) C.Girasis et al Catheter Cardiovasc Interv 2010 Surface mesh represented by stl (stereolithography) file Accuracy Bifurcation of the phantom milling process in 2 halves <10µm

14 Bifurcation phantom filled with contrast

15 CAAS 5.9

16 CAAS 5.9

17 QAngio XA 7.2

18 QAngio XA 7.2

19 QAngio XA 7.2

20 QAngio XA 7.2

21 Inter-observer analysis for QAngio XA Sep 2010-CRF

22 MLD-AP CAAS 5.9 QAngio XA 7.2 Bias= 0.013mm SD= 0.082mm Bias= 0.024mm SD= 0.100mm

23 DS-AP CAAS 5.9 QAngio XA 7.2 Bias= -0.48% SD= 3.66% Bias= -0.60% SD= 4.23%

24 BA-AP CAAS 5.9 Bias= -2.6 deg SD= 3.5 deg

25 MLD-RAO/LAO CAAS 5.9 QAngio XA 7.2 Bias= 0.035mm SD= 0.103mm Bias= 0.052mm SD= 0.107mm

26 DS-RAO/LAO CAAS 5.9 QAngio XA 7.2 Bias= -0.74% SD= 4.52% Bias= -1.02% SD= 4.79%

27 BA-RAO/LAO CAAS 5.9 Bias= -3.1 deg SD= 6.2 deg

28 Contour amendment-ap planes CAAS 5.9* QANGIO XA** 1st obs Plane A 2/18 16/18 Plane B 1/18 15/18 1st obs-intra Plane A 2/18 14/18 Plane B 1/18 11/18 2nd obs-inter Plane A 1/18 14/18 Plane B 1/18 15/18 *Restriction or manual pathline **Use of support points and/or moving carina point

29 Conclusions Accuracy and precision for MLD and DS comparable between softwares, marginally better for CAAS 5.9 Increased variability with QAngio XA 7.2 due to higher need for contour amendment Dedicated algorithm for bifurcation angle calculation available only in CAAS 5.9 QAngio XA Y-shape analysis performance undetected

30 Acknowledgments Ecaterina Cristea, Maria Colon, Ivanka Yankovic (CRF) for Qangio XA inter-observer analysis Yoshinobu Onuma (Erasmus MC) for CAAS interobserver analysis Marie- angèle Morel, Glenda van Bochove, Gerrit-Anne van Es (Cardialysis B.V. Rotterdam) Jolanda Wentzel, Hans Schuurbiers (Bioengineering group, Erasmus MC) Gerhard Koning (Medis), Jean-Paul Aben, Folkert Tijdens (Pie Medical Imaging)