IEC TS 62791:2015(E) defines terms and specifies methods for quantifying the imaging performance of real-time, ultrasound B-mode scanners. The test methodology is applicable for transducers operating in the 2 MHz to 15 MHz frequency range.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 4<\/td>\n | CONTENTS <\/td>\n<\/tr>\n | ||||||
| 8<\/td>\n | FOREWORD <\/td>\n<\/tr>\n | ||||||
| 10<\/td>\n | INTRODUCTION <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | 1 Scope 2 Normative references 3 Terms and definitions <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | 4 Symbols <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 5 General and environmental conditions <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 6 Equipment required 6.1 General 6.2 Phantom geometries 6.2.1 Phantoms for use in the frequency range 2 MHz to 7 MHz 6.2.2 Phantoms for use in the frequency range 7 MHz to 15 MHz including “micro-convex” arrays <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | 6.2.3 Total internal-reflection surfaces 6.2.4 Spatially random distribution of low-echo spheres 6.3 Ultrasonic properties of the tissue-mimicking (TM) phantoms <\/td>\n<\/tr>\n | ||||||
| 18<\/td>\n | 7 Data acquisition assuming a spatially random distribution of low-echo spheres 7.1 Methodology <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | 7.2 Storage of digitized image data Figures Figure 1 \u2013 Flow chart <\/td>\n<\/tr>\n | ||||||
| 20<\/td>\n | 7.3 Digital image files available from the scanner itself 7.4 Image archiving systems 8 Automated data analysis for quantifying low-echo sphere detectability 8.1 General 8.2 Computation of mean pixel values (MPVs) <\/td>\n<\/tr>\n | ||||||
| 22<\/td>\n | Figure 2 \u2013 Schematic of an image plane <\/td>\n<\/tr>\n | ||||||
| 23<\/td>\n | 8.3 Determination of the LSNRm-value for a given depth interval 8.3.1 Preliminaries 8.3.2 Computation of the LSNRn-values and LSNRm-value in a given depth interval 8.3.3 Standard error corresponding to each LSNRn-value <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | Annexes Annex A (informative) Example of a phantom for performance testing in the 2 MHz to 7 MHz frequency range Figure A.1 \u2013 End view of the phantom applicable for 2\u00a0MHz to 7\u00a0MHz showing the spatially random distribution of 4-mm diameter low-echo spheres <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | Figure A.2 \u2013 Top view of phantom with 4 mm-diameter, low-echo spheres <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | Annex B (informative) Illustrations of the computation of LSNRm-values as a function of depth Figure B.1 \u2013 Convex-array image of a prototype 4 mm-diameter low-echo sphere phantom for use in the 2 MHz to 7 MHz frequency range <\/td>\n<\/tr>\n | ||||||
| 27<\/td>\n | Figure B.2 \u2013 Auxiliary figures relating to Figure B.1 Figure B.3 \u2013 Results corresponding to Figures B.1 and B.2, demonstrating reproducibility <\/td>\n<\/tr>\n | ||||||
| 28<\/td>\n | Figure B.4 \u2013 Results corresponding to Figures B.1, B.2 and B.3 Figure B.5 \u2013 One of 80 parallel linear-array images of the phantom containing 4 mm-diameter, low-echo spheres, at 4 MHz with focus at 3 cm <\/td>\n<\/tr>\n | ||||||
| 29<\/td>\n | Figure B.6 \u2013 Three successive images of the set of 80, separated by D\/4 equal to 1\u00a0mm Figure B.7 \u2013 Results for the 4 cm-wide, 3 cm-focus,linear array addressed in Figures B.5 and B.6 <\/td>\n<\/tr>\n | ||||||
| 30<\/td>\n | Figure B.8 \u2013 Results for the 4 cm-wide, 3 cm-focus, linear array addressed in Figures\u00a0B.5, B.6 and B.7, using all 80 image frames corresponding to Figure B.7 <\/td>\n<\/tr>\n | ||||||
| 31<\/td>\n | Annex C (informative) Sufficient number of data images to assure reproducibility of results C.1 General C.2 Phantom with low-echo sphere diameter 3,2 mm, having 2 spheres per millilitre Figure C.1 \u2013 One image obtained from a phantom containing 3,2 mm-diameter, low-echo spheres by using a 4 MHz linear array focused at 3 cm <\/td>\n<\/tr>\n | ||||||
| 32<\/td>\n | Figure C.2 \u2013 Reproducibility result for two independent sets of 70 images with a mean number of low-echo sphere centres that is about 15 per 5 mm-depth interval Figure C.3 \u2013 Results obtained by using both sets of 70 independent images corresponding to Figure C.2 <\/td>\n<\/tr>\n | ||||||
| 33<\/td>\n | Figure C.4 \u2013 Sector image (curved array) at 4,5 MHz with multiple foci at 4 cm, 8 cm and 12 cm depths; the low-echo spheres are 3,2 mm in diameter Figure C.5 \u2013 Reproducibility results for a multiple-lateral-focus (4 cm, 8 cm and 12 cm) case corresponding to Figure C.4 <\/td>\n<\/tr>\n | ||||||
| 34<\/td>\n | C.3 Phantom with 2 mm-diameter, low-echo spheres and 8 spheres per millilitre Figure C.6 \u2013 Reproducibility results for the case corresponding to Figure C.5, except that there is a single focus at 10 cm depth Figure C.7 \u2013 Reproducibility results for the case corresponding to Figure C.5, except that there is a single focus at 4 cm depth <\/td>\n<\/tr>\n | ||||||
| 35<\/td>\n | Figure C.8 \u2013 Image of the phantom containing 2 mm-diameter, low-echo spheres, made with a curved array having 1,5\u00a0cm radius of curvature, with its focus at 3 cm Figure C.9 \u2013 Reproducibility results corresponding to Figure C.8 <\/td>\n<\/tr>\n | ||||||
| 36<\/td>\n | Figure C.10 \u2013 Results using all 100 images in the image set that gave rise to Figure\u00a0C.9 Figure C.11 \u2013 Image of the phantom containing 2 mm-diameter, low-echo spheres, made with a high-frequency (15\u00a0MHz) linear array, laterally focused at 4\u00a0cm <\/td>\n<\/tr>\n | ||||||
| 37<\/td>\n | Figure C.12 \u2013 Reproducibility results corresponding to Figure C.11 Figure C.13 \u2013 Results using all 200 images in the image set that gave rise to Figure C.12 <\/td>\n<\/tr>\n | ||||||
| 38<\/td>\n | Annex D (informative) Example of a phantom for performance testing in the 7 MHz to 15 MHz frequency range <\/td>\n<\/tr>\n | ||||||
| 39<\/td>\n | Figure D.1 \u2013 End- and top-view diagrams of the phantom containing 2 mm-diameter, low-echo spheres for use in the 7 MHz to 15 MHz frequency range <\/td>\n<\/tr>\n | ||||||
| 40<\/td>\n | Figure D.2 \u2013 Image obtained by using the phantom containing 2 mm-diameter, low-echo spheres and a pediatric transducer with a radius of curvature of about 1,5\u00a0cm <\/td>\n<\/tr>\n | ||||||
| 41<\/td>\n | Annex E (informative) Determination of low-echo sphere positions to within D\/8 in x, y and z Cartesian coordinates E.1 Procedure <\/td>\n<\/tr>\n | ||||||
| 42<\/td>\n | E.2 Argument for the choice of seven MPV nearest-neighbour sites for determining the centres of low-echo spheres <\/td>\n<\/tr>\n | ||||||
| 43<\/td>\n | Annex F (informative) Test of total internal reflection produced by alumina and plate-glass, plane reflectors <\/td>\n<\/tr>\n | ||||||
| 44<\/td>\n | Figure F.1 \u2013 Average of 10 images obtained by using a phased array Figure F.2 \u2013 Plot of the data with blue data computed in the left rectangle in Figure F.1 and red data computed in the right rectangle <\/td>\n<\/tr>\n | ||||||
| 45<\/td>\n | Figure F.3 \u2013 Plot of the data when the reflector is on the right side with blue computed in the left rectangle and red computed in the right rectangle <\/td>\n<\/tr>\n | ||||||
| 46<\/td>\n | Figure F.4 \u2013 The percentage by which the mean pixel values resulting from reflections differ from the mean pixel values not involving reflections <\/td>\n<\/tr>\n | ||||||
| 47<\/td>\n | Figure F.5 \u2013 Wide sector (153\u00b0), 1 cm-radius-of-curvature transducer with alumina reflector on the left Figure F.6 \u2013 Plot of the data with blue computed in the left rectangle in Figure F.5 and red computed in the right rectangle <\/td>\n<\/tr>\n | ||||||
| 48<\/td>\n | Figure F.7 \u2013 Plot of the data when the reflector is on the right side with blue computed in the left rectangle and red computed in the right rectangle Figure F.8 \u2013 The percentage by which the mean pixel values resulting from reflections differ from the mean pixel values not involving reflections <\/td>\n<\/tr>\n | ||||||
| 50<\/td>\n | Annex G (informative) Results of a test of reproducibility of LSNRm versus depth for a phantom with 4 mm-diameter low-echo spheres and 2 spheres per millilitre Figure G.1 \u2013 Example image of the phantom with a 4,2 MHz curved array and two low-echo spheres per millilitre <\/td>\n<\/tr>\n | ||||||
| 51<\/td>\n | Figure G.2 \u2013 Reproducibility results corresponding to the image set, one of which is shown in Figure G.1 <\/td>\n<\/tr>\n | ||||||
| 52<\/td>\n | Annex H (informative) Results for low-echo sphere-concentration dependence of LSNRm versus depth for phantoms with 4 mm-diameter spheres Figure H.1 \u2013 Example of an image from the image set giving rise to the results in Figure H.2; the phantom contained an average of one 4 mm-diameter, low-echo sphere per millilitre <\/td>\n<\/tr>\n | ||||||
| 53<\/td>\n | Figure H.2 \u2013 Results corresponding to an image set,one of which is shown in Figure H.1 Figure H.3 \u2013 Example of an image from the data set giving rise to the results in Figure H.4; the phantom contained an averageof two 4 mm-diameter, low-echo spheres per millilitre <\/td>\n<\/tr>\n | ||||||
| 54<\/td>\n | Figure H.4 \u2013 Results corresponding to an image set,one of which is shown in Figure H.3 <\/td>\n<\/tr>\n | ||||||
| 55<\/td>\n | Annex I (informative) Results for low-echo sphere-concentration dependence of LSNRm versus depth for phantoms with 3,2 mm-diameter spheres Figure I.1 \u2013 Example of an image from the 4 ml-1 data set producing the results shown in Figure I.2 <\/td>\n<\/tr>\n | ||||||
| 56<\/td>\n | Figure I.2 \u2013 Results for the phantom containing four 3,2 mm-diameter, low-echo spheres per millilitre Figure I.3 \u2013 Example of an image from the 2 ml-1 data set producingthe results shown in Figure I.4 <\/td>\n<\/tr>\n | ||||||
| 57<\/td>\n | Figure I.4 \u2013 Results for the phantom containing two 3,2 mm-diameter, low-echo spheres per millilitre Figure I.5 \u2013 Example of an image from the 1 ml-1 data set producing the results shown in Figure I.6 <\/td>\n<\/tr>\n | ||||||
| 58<\/td>\n | Figure I.6 \u2013 Results for the phantom containing one 3,2 mm-diameter, low-echo sphere per millilitre <\/td>\n<\/tr>\n | ||||||
| 59<\/td>\n | Annex J (informative) Comparison of two different makes of scanner with similar transducers and console settings Figure J.1 \u2013 Results for System A scanner and 7CF2 3-D (swept convex array) transducer focused at 4 cm and operated at 4,5 MHz in 2-D mode Figure J.2 \u2013 Results for System B scanner with a 4DC7-3 3-D (convex array) transducer, operated at 4 MHz in 2-D mode and focused at 4 cm. The sector angle and all other console settings mimicked those for the System A case (Figure J.1) <\/td>\n<\/tr>\n | ||||||
| 61<\/td>\n | Annex K (informative) Special considerations for 3-D probes K.1 3-D probes operating in 2-D imaging mode K.2 2-D arrays operating in 3-D imaging mode for determining LSNRm-values as a function of depth for reconstructed images K.3 Mechanically driven 3-D probes operating in 3-D imaging mode <\/td>\n<\/tr>\n | ||||||
| 62<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Ultrasonics. Pulse-echo scanners. Low-echo sphere phantoms and method for performance testing of gray-scale medical ultrasound scanners applicable to a broad range of transducer types<\/b><\/p>\n |