From Analysis Method to Quantitative Imaging Biomarker

Transcription

1 From Analysis Method to Quantitative Imaging Biomarker Developments in Healthcare Imaging Connecting with Industry 18 th October 2017 Sarah Lee, PhD, SMIEEE Medical Image Analysis Consultant

2 Disclosures Consultant to GE Healthcare and GSK This talk is sponsored by GSK 2

3 Contents Motivation Introduction of QIB From analysis method to QIB Quantitative Imaging Biomarkers Alliance Summary 3

4 Motivation Refs: Sarah Lee and Tania Stathaki (2005) Mammogram analysis using two-dimensional autoregressive models: sufficient or not? Proc. 13 th International Conference on Image Analysis and Processing, pp , LNCS MIAS website: 4

5 Introduction to QIB Quantitative imaging biomarkers (QIBs) are objective characteristics derived from in vivo images as indicators of normal biological processes, pathogenic processes, or response to a therapeutic intervention (Sullivan et al., 2015) Reference: Sullivan et al. (2015) Metrology Standards for Quantitative Imaging Biomarkers. Radiology 277:813:25. 5

6 Quantitative image biomarkers QIBs can be anatomical, e.g., o Oncology: tumour size o Alzheimer s disease: size of hippocampus o Neurological disorders: white matter lesions (hyperintensity) functional, e.g., o Physiological aspects of the tumours in the image such as cellularity or vascularity o Brain responses in a controlled experiment Image sources: White matter hyperintensity: WMH Segmentation Challenge Fig 2 from YS Cheah, S Lee et al. (2014) Ageing diminishes the modulation of human brain responses to visual food cues by mean ingestion. International Journal of Obesity 38:

7 Analysis Method From Analysis Method to QIB Diagnostic or prognostic Predictive Response Monitoring Ref: QIBA Technical Performance Working Group (2015) Quantitative Imaging Biomarkers: A Review of Statistical Methods for Technical Performance Assessment. Stat Methods Med Res 24: Image source: 7

8 Analysis Method Technical performance assessment From Analysis Method to QIB Accuracy/Bias Precision Outlier? - Is ground truth available? - Is application-specific phantom available? - What is considered as outlier? - How does your algorithm deal with outlier? Ref: QIBA Technical Performance Working Group (2015) Quantitative Imaging Biomarkers: A Review of Statistical Methods for Technical Performance Assessment. Stat Methods Med Res 24: Image sources: 8

9 Analysis Method Technical performance assessment Day 1 Day5 From Analysis Method to QIB Accuracy/Bias Repeatability Precision Reproducibility - Test/re-test - Repeatability coefficient Ref: QIBA Technical Performance Working Group (2015) Quantitative Imaging Biomarkers: A Review of Statistical Methods for Technical Performance Assessment. Stat Methods Med Res 24: Image sources: 9

10 Analysis Method Technical performance assessment From Analysis Method to QIB Accuracy/Bias Repeatability Precision Reproducibility Day 1 Day5 - Different scanners - Different days - Different operators - Reproducibility coefficient Ref: QIBA Technical Performance Working Group (2015) Quantitative Imaging Biomarkers: A Review of Statistical Methods for Technical Performance Assessment. Stat Methods Med Res 24: Image sources: 10

11 Analysis Method Technical performance assessment Clinical validation From Analysis Method to QIB Accuracy/Bias Repeatability Precision Reproducibility - Demonstrating that a biomarker is associated with a clinical endpoint - The QIB is a measurable indicator of a pathological process, a biological process or response to an intervention Ref: QIBA Technical Performance Working Group (2015) Quantitative Imaging Biomarkers: A Review of Statistical Methods for Technical Performance Assessment. Stat Methods Med Res 24:

12 Validate your algorithm using a wide range of relevant data o From different scanners o From a larger cohort o From different cohorts Open source data Bigger data Sources: Lung CT database: The Alzheimer s Disease Neuroimaging Initiative (ADNI): Parkinson s Progression Markers Initiative (PPMI): UK Biobank: 12

13 Quantitative Imaging Biomarker Alliance (QIBA) An Radiological Society of North America (RSNA) initiative Mission: To improve the value and practicality of QIBs by reducing variability across devices, patients, and time To produce a description of a QIB in sufficient detail that it can be considered as a validated assay o The measurement bias and variability are both characterised and minimised Ref: Obuchowski NA et al. (2015) Quantitative imaging biomarkers: a review of statistical methods for computer algorithm comparisons. Statistical Methods in Medical Research 24: QIBA website: 13

14 QIBA Profiles Development Public Comment Consensus Technically confirmed The Biomarker Committee experts have drafted the profile and believe it is practical and expect it to achieve the claimed performance The wider community has read the profile and believe it to be practical and expect it to achieve the claimed performance Several sites have performed the profile and found it to be practical and expect it to achieve the claimed performance Claim confirmed Some sites have performed the profile and found it achieved the claimed performance Clinically confirmed Many sites have performed the profile and demonstrated the claimed performance is widely achievable Ref: 14

15 Stage 3: Technically confirmed profile QIBA Profile: FDG-PET/CT as an Imaging Biomarker Measuring Response to Cancer Therapy Image Analysis: Detailed description of (1) ROI extraction (2) Standard uptake value computation Ref: FDG-PET/CT Technical Committee. FDG-PET/CT as an Imaging Biomarker Measuring Response to Cancer Therapy, Quantitative Imaging Biomarkers Alliance, Version 1.13, Technically Confirmed Version. QIBA, November 18, Available from: RSNA.ORG/QIBA. Image source: Figure 3 from the reference 15

16 Quantitative imaging biomarkers have been increasingly used in clinical trials and clinical practices Summary The advances of QIB also rely on analysis method development The technical performance of QIBs should be considered while developing analysis methods Initiatives such as QIBA have profiles set up that bridge analysis method and QIB 16