1. Topic Report Sensitivity and Specificity for OCT Diagnosis Advisor: Sheng-Lung Huang Speaker: Yao - Sheng Lin

2. Outline Definition – Positives, Negatives, Sensitivity, Specificity Example 1 Example 2 Properties Application (on OCT, ultrasound ) Other applications Conclusion 1

3. Definition Sensitivity and specificity are statistical measures of the performance of a binary classification test. 2

4. Definition : positives, negatives True positive ( 真陽性 ): sick people correctly identified as sick False positive ( 假陽性 ): healthy people incorrectly identified as sick True negative ( 真陰性 ): healthy people correctly identified as healthy False negative ( 假陰性 ): sick people incorrectly identified as healthy 3

5. Definition : sensitivity 4

6. Definition : specificity 5

7. Example 1 生病者健康者 陽性 70 (a)10 (b)80 (a+b) 陰性 30 (c)90 (d)120 (c+d) 100 (a+c)100 (b+d) http://www.mmh.org.tw/taitam/medical_edu/www/default.asp?cont entID=644 6

8. Example 1 生病者健康者 陽性 70 (a)10 (b)80 (a+b) 陰性 30 (c)90 (d)120 (c+d) 100 (a+c)100 (b+d) Sensitivity – 所有生病者中被診斷為陽性的比率 70 / (70+30) = 70% Specificity – 所有健康者中被診斷為陰性的比率 90 / (10+90) = 90% 7

9. Example 2 false positive 多，代表沒病被誤診成有病的人多，也就是沒病的人正確診斷的 比率低，所以 low specificity 。 相對地， false negative 少，代表有病被誤診成沒病的人少，也就是有病的人 被正確診斷的比率高，所以 high sensitivity 。 陰性陽性 假陰性 ( 藍色小球 ) 假陽性 ( 紅色小球 ) 8

10. Properties If a test has high sensitivity, a negative result means a high probability of the absence of disease. If a test has high specificity, a positive result means a high probability of the presence of disease. Trade-off 9

11. Properties There is a trade-off between S and SP. 改變診斷標準 : I1 I2 higher S, lower SP I1 I3 lower S, higher SP 10 http:// biostatistics.cmu.edu.tw/online/teaching_corner_001.pdf

12. Application 11 Purpose: Compare the diagnostic accuracy of OCT and intravascular ultrasound for the detection and characterization of coronary plaque composition ex vivo.

13. Golden Standard : Histology 12 (A)Normal (B)Fibrous plaque (C)Calcified plaque (D)Lipid-rich plaque coronary vessel wall

14. Diagnostic criteria of OCT 13 (A) Normal -regular 3 layer (B) Fibrous plaque -intimal thickening -bright and homogeneous signal (C) Calcified plaque -intimal thickening -low signal -sharp borders (D)Lipid-rich plaque -intimal thickening -low signal -diffuse borders coronary vessel wall

15. Diagnostic criteria of ultrasound 14 (A) Normal -monolayer (B) Fibrous plaque -intimal complex thickening -echogenicity between ca and lc (C) Calcified plaque -bright echoes (D)Lipid-rich plaque - intimal complex thickening -echolucent signal appearance coronary vessel wall

16. Results 15 OCT demonstrated great performance on the most plaque types.

17. Optical coherence tomography achieved a sensitivity of 85% and a specificity of 78% in the assessment of oral potentially malignant and malignant disorders. OCT had a sensitivity of 100%, overall specificity of 89% for identified bladder epithelial lesions. The specificity of fluorescence detection was significantly enhanced by FG-OCT (53%and 93%, respectively, p 0.0001). The sensitivity of fluorescence detection and FG-OCT was79% and 100% sensitivity was 98 and 96 percent for both investigators, respectively, and the specificity was 39 and 41 percent 16

18. Other applications 17 diseasesensitivityspecificity potentially malignant disorders 85%78% bladder epithelial lesion100%89% bladder cancer100%93% Cervical cancer96%41%

19. Conclusion 18 S t, sp tell OCT in diff region of medical research(data) OCT >ultra

20. Conclusion OCT is superior to intravascular ultrasound for the classification of coronary atherosclerotic plaque composition. OCT demonstrated great performance in a variety of disease diagnoses. 19

21. Thanks for your listening! 20