1. International Atomic Energy Agency Image Quality in Cardiac Angiography L 8.1

2. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography2 Educational Objectives 1.How can image quality of cardiac angiographic images be assessed? 2.How useful can the quality criteria be?

3. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography3 Rotter, EHJ 2003 +112% +204% +75% Interventional cardiology in Europe 1992-1999

4. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography4 EHJ 2001, 2003 PCI in some European Countries (1994-1999) Ger Fra UK Ita Nl Spa 1200 2081 825 1443 242 484 239 763 800 818 267 858 1994 1996 1999 per million

5. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography5 Quality of cardiac images background cardiac cine-angiographic images should allow the cardiologist to evaluate the anatomic (and sometimes functional) details which are relevant for clinical decision making variables technical performance of the imaging system patient cooperation angiographic technique

6. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography6 quality it’s me !! the interventional cardiologist and quality…

7. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography7 Scientific societies implemented guidelines to guarantee adequate level of quality and performance of invasive cardiology training of operators quantitative standards to maintain the expertise in coronary angiography or angioplasty quality-assurance programme Pepine, J Am Coll Cardiol 1995;25:14–6 Miller, Can J Cardiol 1996;12:470–2 Cowley, Cathet Cardiovasc Diagn 1993;30:1–4 Heupler, Cathet Cardiovasc Diagn 1993;30:191–200 Scanlon, J Am Coll Cardiol 1999;33:1756–824 Quality in invasive cardiology and scientific societies

8. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography8 the specific problem of achieving and maintaining high-quality standards in angiographic imaging responsibility of cardiac catheterization laboratory directors involves periodic cine-angiograms review lesion quantification (QCA, calipers) precise criteria have never been stated for coronary procedures Quality of cardiac images and scientific societies

9. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography9 do we need a method for image quality assessment in the routine practice of diagnostic (and interventional) cardiology

10. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography10 Types of technical deficiencies in 308 cineangiograms (Leape, Am Heart J 2000;139:106-13) N %

11. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography11 Percentage of inadequate studies by different hospitals (Leape, Am Heart J 2000;139:106-13) In 12/29 hosp. 50% of studies had deficencies 6 of these are teching hosp.

12. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography12 CountryDAP (Gy×cm 2 )FT (min)No. of frames medianmeanmedianmeanmedianmean Greece38.646.75.57.11620960 Spain27.839.46.49.49031596 Italy28.233.53.04.2570610 England28.233.53.04.2570610 Ireland33.337.53.24.4580585 Finland39.652.74.14.8417803 mean fluoroscopy time, frame number and dose-area product (DAP) in some European centers during coronary angiography Neofotistou, ER 2003 + 41% + 113% + 288%

13. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography13 projections’ distribution mean number of series DIMOND 3 data focus-detector mean distances

14. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography14 based on measurement of some physical parameters system transfer factor K spatial resolution (MTF, modulation transfer function) detective quantum efficiency (DQE) noise they are rather complex and rarely applied to daily practice quality evaluation of angiographic images objective methods

15. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography15 test objects or phantoms they are able to simulate the same radiation conditions as the part of the body they describe behaviour of radiology equipment in specific operating condition evaluation of clinical images allow evaluation of the overall performance including patient’s collaboration and technique quality evaluation of angiographic images subjective methods

16. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography16 test objects

17. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography17 binary classification pre-defined feature identification, normal vs. abnormal (this is typically used with test objects ) correct answer must be known borderline visibility progressive judgement in terms of quality variable level quality (clarity of thoracic calcification, arrange images in order of preference) strength of agreement by different observers gives indications on superiority quality evaluation of angiographic images clinical images produced in different conditions

18. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography18 1:801:501:1 “lossy” compression “lossy” compression

19. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography19

20. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography20 proper filtering improper filtering

21. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography21 set of reference images difficult to obtain use limited settings where perceptibility of abnormal feature is under experimenter’s control quality measurement is only relative clinical adequacy not evaluated quality evaluation of angiographic images limitations

22. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography22 quality of images is assessed in comparison to pre- specified criteria to comply with effective and relevant in clinical practice radiographic images (Maccia, Radiat Protect Dosim 1995; Vañò, Br J Radiol 1995, Radiat Prot Dosim 1998; Perlmutter, Radiat Prot Dosim 1998) CT scan (Calzado, Radiat Prot Dosim 1998) quality evaluation of angiographic images method of quality criteria

23. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography23 1995-1996: GISE Società Italiana di Cardiologia Invasiva and AIFM Associazione Italiana di Fisica Biomedica 1996–2003: European Concerted Action DIMOND Cardiology Group (Digital Imaging: Measures for Optimizing Radiological INformation Content and Dose) contracts FI 4P-0042DG12-WSMN, FIGM-CT-2000-00061-DIMOND http://www.dimond3.org/ development of Quality Criteria

24. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography24 Diagnostic requirements adapted from EUR 16260 EN Image criteria In most cases specify important anatomical structures that should be visible on an image to aid accurate diagnosis. Some of these criteria depend fundamentally on correct positioning and cooperation of the patient or good angiographic technique, whereas others reflect technical performance of the imaging system Important image details Provide quantitative information on the minimum sizes at which important anatomical details should become visible on the image. Some of these anatomical details may be pathological and therefore may not be present (ex. mitral insufficiency)

25. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography25 Objectives to set guidelines and give methods for the evaluation of image quality in – Left Ventriculography – Left Coronary Angiography – Right Coronary Angiography – Angiography of Venous Graft or Arterial Free Graft – Angiography of Left Mammary Artery ‘In Situ’ Model European guidelines on quality criteria for diagnostic radiographic images (EUR 16260 EN) where the diagnostic requirements and image criteria are settled

26. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography26 What was not intended to repeat what has already been included in the manuals of Coronary Angiography, but to give some guidelines about how an angiogram should appear provided that good equipment and a correct angiographic technique are used Warnings under no circumstances should an image which fulfils all clinical requirements but does not meet all image criteria ever be rejected* *EUR 16260 EN

27. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography27 Clinical criteria are defined as important anatomical features that should be visible; the level of visualisation is as follows  visualization: characteristic features are detectable, but details are not fully reproduced (features just visible)  reproduction: details of anatomical structures are visible, but not necessarily clearly defined (details emerging)  visually sharp reproduction: anatomical details are clearly defined (details clear) Technical criteria  help to asses the technical quality of the procedure  features not necessarily impair the clinical information content (panning, arms position, etc.) Aspects of an optimised angiographic technique  set of technical information  aimed to an optimised radiological technique  not mandatory definition of terms

28. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography28 visualization: characteristic features are detectable, but details are not fully reproduced (features just visible)

29. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography29 reproduction: details of anatomical structures are visible, but not necessarily clearly defined (details emerging)

30. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography30 visually sharp reproduction: anatomical details are clearly defined (details clear)

31. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography31 1) Visually sharp reproduction of the origin, proximal, mid (especially the crux region) and distal portion in at least two orthogonal views, with minimal foreshortening and overlap 2) Visually sharp reproduction of side branches  1.5 mm in at least two orthogonal views, with minimal foreshortening and overlap. The origin should be seen in at least one projection 3) Visually sharp reproduction of lesions in vessels  1.5 mm in at least two orthogonal views, with minimal foreshortening and overlap 4) Visualization of collateral circulation when present clinical criteria for RCA projections based on operator’s choice

32. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography32 1) Simultaneous and full opacification of the vessel lumen at least until the first flow-limiting lesion (in general ~ 90-95% by visual estimation) 2) Performed at full inspiration if necessary to avoid diaphragm superimposition or to change anatomic relationship (in apnoea in any case) 3) Arms should be raised clear of the angiographic field 4) Panning should be limited. If necessary, pan in steps rather than continuously, or make subsequent cine runs to record remote structures 5) When clinical criteria 1-4 have been fulfilled, avoid extra projections (mainly LAO semi-axial) technical criteria

33. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography33 aspects of an optimised angiographic technique 1) Use of the wedge filter on bright peripheral areas 2) 2-3 sequences (except for difficult anatomic details) 3) 12.5-15 frames/s (25-30 only if heart rate exceeds 90- 100 bpm or in paediatric patients) 4) 60 images per sequence at average (12.5-15 fr/s) except if collaterals have to be imaged or in case of slow flow

34. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography34 Are these criteria, derived from a model studied for static radiological imaging, suitable for the more complex cine- angiogram examinations ? Based on these criteria, is it possible to evaluate and quantify quality in an objective way ? questions on DIMOND Quality Criteria

35. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography35 problems related to subjective evaluation of images ……

36. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography36 problems related to subjective evaluation of images ……

37. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography37 the method of image quality evaluation based on DIMOND Quality Criteria

38. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography38 the method of image quality evaluation based on DIMOND Quality Criteria

39. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography39 the method of image quality evaluation based on DIMOND Quality Criteria

40. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography40 example of quality score calculation (QS) for RCA

41. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography41                

42. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography42 sum of scores = 91 (actual score) maximum theoretical score = 96 QS = actual score/theoretical score % = 65/88x100 = 94%                 example of QS calculation for RCA

43. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography43 total score (mean and std dev.) 15 angio, 65 readings, 3 european centers % within pts variability = 0.08 Lin’s coeff =.76 (CI.67-.84) AJC, 1999 (abs)

44. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography44 total score (mean and std dev.) 30 angio, 160 readings, 6 european centers %

45. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography45 total scores compared to subjective opinion “good” and “acceptable” two cases lacking

46. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography46 what is ? good I get all the information needed to treat the patient and I like this examination acceptable I get all the information needed to treat the patient but I don’t like very much this examination unacceptable I don’t get all the information needed to treat the patient and I don’t like this examination at all

47. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography47 Remarks the method based on Quality Criteria applies to cardiac angiography reproducibility is good measure of clinical acceptability seems improved in comparison to subjective opinion the method “forces” to a systematic and standardized analysis of the images specific training not requested (but it may improve agreement)

48. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography48 Criteri di Qualit à dell ’ Immagine Cineangiografica (documento preliminare). Emodinamica 1997; 10 (suppl.): 9-11 Quality criteria of imaging in diagnostic and interventional cardiology. TCT-196: Am J Cardiol, 1999:84(6A):73P-74P A method based on DIMOND Quality Criteria to evaluate imaging in diagnostic and interventional cardiology. Radiat Prot Dosim 2001;94:167-172 Quality Criteria for cardiac images in diagnostic and interventional cardiology. Br J Radiol 2001; 74:852-855 Quality Criteria published papers

49. Radiation Protection in Cardiology Lecture 8.1: Image quality in cardiac angiography49 closing remarks image quality is not warranted in coronary angiography a great variability is found in common practice among different operators and radiological exposure varies considerably image quality assessment plays a pivotal role in the optimisation of angiographic procedures optimisation implies a continuous process of research and audit which should involve  Scientific Societies  single operators  cooperation of all professionals in the Cath. Lab.