Quality control of breast ultrasound: How to use a breast ultrasound quality assurance phantom?

Transcription

1 Quality control of breast ultrasound: How to use a breast ultrasound quality assurance phantom? Poster No.: C-2282 Congress: ECR 2013 Type: Educational Exhibit Authors: S. J. Oh, B. K. Seo, S. E. Song, K. R. Cho, O. H. Woo, S H. Cha ; Ansan-si Gyeonggi-do/KR, Ansan/KR, Seoul/KR, 4 Ansan/KR Keywords: Diagnostic procedure, Ultrasound, Breast, Cancer DOI: /ecr2013/C-2282 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 15

2 Learning objectives Purpose To demonstrate scanning and assessment methods of the breast US QA phantom Emphasizes importance of quality control of breast US imaging with the phantom Index I.Composition of breast US QA phantom II.Scanning and assessment methods of the breast US QA phantom III.Importance of regular quality control with the breast US QA phantom for improving diagnostic performance Background High-frequency transducer around 10 MHz Used for breast US examination Easily influenced by imaging parameters Regular quality check of US images with a phantom : essential!! To maintain consistency of the performance of scanners and transducers To improve diagnostic performance in patients' study Imaging findings OR Procedure details I. Composition of breast US QA phantom Two types of block a: mass target block b: dot target block Four types of targets Gray scale targets Page 2 of 15

3 Cyst targets Dot targets 45 degrees line targets II. Scanning and assessment methods of the breast US QA phantom *US machine 1.Start 15mins later after turn on the machine. 2.Use the frequency of transducer recommended by guidelines of breast US diagnosis 3.Fix the depth at 40mm 4.Fix the focus at one target point 5.Do as usual conditions such as brightness of monitor, contrast and room illumination 6.Prepare the echo coppler *QA phantom 1.Use it on the flat table 2.Fix the internal temperature as 23-26'c 3.Put jelly on phantom 4.Always use the probe, vertical to phantom 1.Scan under the same mode of usual breast US exam 2.Get an image at 1cm and 2cm target with single focus 3.Gray scale targets -From the hypoechoic to hyperechoic target, find the gain level that can show gradual gradation -Because the probe entrance diameter is short, we should divide the whole target and repeat image on next scanning -Scan the target to get a best image with no blurring and sharp round shape 4.Cyst targets -Always be careful of the shape of circle and good resolution of edge -Targets can be shaped slight longitudinally because the sound velocity through the phantom is slight slow 5.Dot targets -Should be aware of the directional resolution on transversally scattered dots, and distant resolution on vertically scattered dots Page 3 of 15

4 6.45 degrees line targets -Place the probe vertical to the target (use echo coppler if you have) and then slowly move it to the center of the phantom. -Scan when the targets can be seen in the center of 2 guidelines. -The distance between two dots is 2mm and you can evaluate the resolution through the thick portion of slice. III. Assessment methods of the breast US QA phantom 1. Evaluate the quality of scanned image 2. Evaluate the base, whether it appears homogeneously and does not show any speckles 3. Evaluate the target 1)Gray scale target shows almost round shape and internal echogenicity is sequentially changed. 2)Cyst target shows almost round shape and even 1mm sized target is clearly seen. 3)Dot target can be recognized more than 5 in vertical direction and more than 4 in horizontal direction. 45 degrees line targets appears as #2mm **4)fulfill 1)+ 2)+ 3) in both 1cm and 2cm target 4) in any 1cm or 2cm target 2) clearly appears even 1mm sized target Images for this section: Page 4 of 15

5 Fig. 1: I. Composition of breast US QA phantom Page 5 of 15

6 Fig. 2: Gray scale targets Page 6 of 15

7 Fig. 3: Cyst targets Page 7 of 15

8 Fig. 4: II. Scanning and assessment methods of the breast US QA phantom 3. Gray scale targets Page 8 of 15

9 Fig. 5: II. Scanning and assessment methods of the breast US QA phantom 3.Gray scale targets Page 9 of 15

10 Fig. 6: II. Scanning and assessment methods of the breast US QA phantom 3.Gray scale targets Page 10 of 15

11 Fig. 7 Page 11 of 15

12 Fig. 8: II. Scanning and assessment methods of the breast US QA phantom 4. cyst targets Page 12 of 15

13 Fig. 9: II. Scanning and assessment methods of the breast US QA phantom 4. cyst targets Fig. 10: II. Scanning and assessment methods of the breast US QA phantom 5. dot targets Page 13 of 15

14 Fig. 11: II. Scanning and assessment methods of the breast US QA phantom 6.45 degrees line targets Page 14 of 15

15 Conclusion III. Importance of regular quality control with breast US QA phantom for improving diagnostic performance Purpose of using US QA phantom Always makes the same condition and parameters of breast US machine through the regular check up of phantom, so you can notice the difference or deterioration of image resolution. Without the proper image quality of US machine Accuracy rate would be poorincrease the re-examination ratemiss the treatment opportunity Conclusion 1. Image quality assessment with a US phantom is easy and convenient 2. Quality control of a phantom is important to maintain imaging quality in clinics and improve diagnostic accuracy for breast examination. References ######## 2008;58: Breast QA phantom manual (US-4) Copyright CMP Trading Co., Personal Information Page 15 of 15