Ultrasonics In Medicine Research Articles

Potential of Artificial Intelligence for Estimating Japanese Fetal Weights.

We developed an artificial intelligence (AI) method for estimating fetal weights of Japanese fetuses based on the gestational weeks and the bi-parietal diameter, abdominal circumference, and femur length. The AI comprised of neural network architecture was trained by deep learning with a dataset that consists of ± 2 standard devia-tion (SD), ± 1.5SD, and ± 0SD categories of the approved standard values of ultrasonic measurements of the fetal weights of Japanese fetuses (Japan Society of Ultrasonics in Medicine [JSUM] data). We investigated the residuals and compared 2 other regression formulae for estimating the fetal weights of Japanese fetuses by t-test and Bland-Altman analyses, respectively. The residuals of the AI for the test dataset that was 12.5% of the JSUM data were 6.4 ± 2.6, -3.8 ± 8.6, and -0.32 ± 6.3 (g) at -2SD, +2SD, and all categories, respectively. The residu-als of another AI method created with all of the JSUM data, of which 20% were randomized validation data, were -1.5 ± 9.4, -2.5 ± 7.3, and -1.1 ± 6.7 (g) for -2SD, +2SD, and all categories, respectively. The residuals of this AI were not different from zero, whereas those of the published formulae differed from zero. Though vali-dation is required, the AI demonstrated potential for generating fetal weights accurately, especially for extreme fetal weights.

Formulae Based on Biomathematics to Estimate the Standard Value of Fetal Growth of Japanese.

We devised biomathematics-based formulae to estimate the standard values of fetal growth of Japanese after 22 weeks' gestation. The growth rates of bi-parietal diameter (BPD), abdominal circumference (AC), femur length (FL), and estimated fetal body weight (EFBW) at the time of gestation were assumed to be proportional to the product of the value at the time and the rest value of an unknown maximum value, respectively. The EFBW was also assumed to follow a multiple logistic function of BPD, AC and FL to fit the standard values of Japanese fetuses published by the Japan Society of Ultrasonics in Medicine. The Mann-Whitney test was used for statistical analysis. The values as a function of gestational day, t, were as follows: BPD(t)=99.6/(1+exp (2.725-0.01837＊t)) (mm); AC(t)=39.7/(1+exp (2.454-0.01379＊t)) (cm); FL(t)=79.6/(1+exp (2.851-0.01710＊t)) (mm); EFBW(t)=8045.1/(1+exp (6.028-0.06582＊BPD(t)-0.1469＊AC(t)+ 0.07377＊FL(t))) (g). EFBW as a function of BPD, AC and FL was as follows: EFBW=8045.1/(1+exp (4.747+ 0.02584＊BPD+0.1010＊AC-0.1416＊FL)) (g). When the BPD, AC and FL were at -2 standard deviation (SD), -1SD, mean and + 2SD, the EFBW values calculated by the formula were statistically closer to the standard values than conventional formulas with p-values of 4.871×10-7, 4.228×10-7, 9.777×10-7 and 0.028, respectively. The formulae based on biomathematics might be useful to estimate the fetal growth standard values.

Ultrasonographic features of pure ductal carcinoma in situ of the breast: correlations with pathologic features and biological markers.

PurposeThe purpose of this study was to evaluate the ultrasonographic features of pure ductal carcinoma in situ (DCIS) of the breast and to evaluate the correlations of ultrasonographic features with pathologic and biological features.MethodsA total of 141 lesions in 138 women with pure DCIS who underwent preoperative breast ultrasonography were retrospectively reviewed. Ultrasonographic features were analyzed using the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) ultrasonography lexicon and the diagnostic criteria of the Japan Society of Ultrasonics in Medicine. Pathologic features including the nuclear grade and presence of comedonecrosis were evaluated. Biological markers including estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) status, as well as the Ki-67 index, were recorded. Ultrasonographic features were compared with pathologic findings and biological markers using the chi-square test. P-values of <0.05 were considered to indicate statistical significance.ResultsOf the 141 lesions, 75 (53.2%) were mass lesions, 56 (39.7%) were non-mass lesions, and 10 (7.1%) were not visible. The most common feature of the mass pattern was a mass with irregular shape (32.6%), an indistinct margin (27.7%), and hypoechogenicity (37.6%). Microcalcifications were observed in 48 cases (36.6%) as an associated feature. Calcifications outside of a mass were more common than calcifications within a mass. Ultrasonographic microcalcifications and ductal changes were frequently observed in non-mass lesions. Ultrasonographic non-mass lesions were associated with high-grade DCIS (P=0.004) and the presence of comedonecrosis (P=0.006). Microcalcifications were significantly associated with high-grade DCIS (P<0.001), the presence of comedonecrosis (P<0.001), an elevated Ki-67 (P<0.001), and HER2 positivity (P=0.003).ConclusionThe most common ultrasonographic feature of pure DCIS was an irregular, hypoechoic mass with an indistinct margin. Ultrasonographic microcalcifications and ductal changes were more frequent in non-mass lesions, which were correlated with poor prognostic factors, such as a high nuclear grade, comedonecrosis, HER2 positivity, and an elevated Ki-67 index.

Report of The 89th Annual Scientific Meeting of the Japan Society of Ultrasonics in Medicine, The 12th Congress of the Asian Federation of Societies for Ultrasound in Medicine and Biology, and The 8th Asian Conference on Ultrasound Contrast Imaging (Ultrasonic Week 2016).

Report of The 89th Annual Scientific Meeting of the Japan Society of Ultrasonics in Medicine, The 12th Congress of the Asian Federation of Societies for Ultrasound in Medicine and Biology, and The 8th Asian Conference on Ultrasound Contrast Imaging (Ultrasonic Week 2016).

Deployment of portable ultrasound machines to Great East Japan Earthquake-Stricken Area by the Japan Society of Ultrasonics in Medicine: lessons learned from Iwate Prefecture

Deployment of portable ultrasound machines to Great East Japan Earthquake-Stricken Area by the Japan Society of Ultrasonics in Medicine: lessons learned from Iwate Prefecture

東日本大震災時における日本超音波医学会事務局の対応

東日本大震災時における日本超音波医学会事務局の対応

In memory: Floyd Dunn.

I was deeply saddened when I heard that Professor Floyd Dunn, a groundbreaking pioneer in the science of ultrasound and bioacoustics, passed away on January 24, 2015. His death came just 30 days after that of his wife Elsa. He was born in Kansas City, MO, USA in 1924. He attended the University of Illinois (UI) at Urbana-Champaign in the Department of Electrical and Computer Engineering, earning three degrees, including his Ph.D. in 1956. He remained at UI for 50 years, and during that period he directed the Bioacoustics Research Laboratory at UI for more than 20 years. His research interests included bioeffects, safety of ultrasound, ultrasonic imaging used for prenatal sonograms, the ultrasonic microscope, and numerous measurement tools. He carried an appointment at the University of Arizona, Tucson after his retirement from UI in 1995. He was a member of both the National Academy of Sciences and the National Academy of Engineering. He was also the past President of the Acoustical Society of America (ASA). He was a recipient of the IEEE Edison Medal, the ASA Gold and Silver Medals, as well as the AIUM William J. Fry Memorial Lecture Award in 1984 and the AIUM Joseph P. Holmes Basic Science Pioneer Award in 1990. Not only in the US, USSR, or United Kingdom, he also taught and led ultrasound research in Japan. Of note, he annually visited Sendai for more than 15 years after he spent 1 year on his sabbatical at Tohoku University in 1989. During his stay in Sendai, he taught young researchers topics ranging from the principle of ultrasound to advanced technology in medical ultrasound. I was grateful that he edited my papers for both content and English grammar before submission to Ultrasound in Medicine and Biology again and again. Together with Professors Motonao Tanaka, Shigeo Ohtsuki, and me, he edited a monogram titled ‘‘Ultrasonic Tissue Characterization’’ published by Springer in 1996. He influenced many of Japan’s leading researchers in medical ultrasound including Professors Daitaro Okuyama, Noriyoshi Chubachi, Motonao Tanaka, Hiroshi Inoue, Jun-ichi Kushibiki, Nobuyuki Endoh, Shin-ichiro Umemura, Hiroaki Okawai, Hiroshi Kanai, and Hideyuki Hasegawa. For his achievements in research and education in medical ultrasound in Japan, he was awarded as an honorary member of the Japan Society of Ultrasonics in Medicine in 1990. Personally, I visited him in 2012 when the AIUM annual meeting was held in Phoenix, AZ. At that time, I drove a Ford rent-a-car to Tuscan from Phoenix and he drove his Lexus sports car to the meeting venue. He was very sharp and remembered the names of most people he met in Sendai, not only researchers but also their families and secretaries. I will forever be grateful for Dr. Dunn’s generosity and support. My deepest sympathies and prayers for his family, friends, and colleagues. & Yoshifumi Saijo saijo@idac.tohoku.ac.jp

Diversity in ultrasonics

I recently had the opportunity to read about research on ecological surveys involving wild animals such as penguins, seals and whales. A technique called ‘‘bio-logging’’ involves the attaching of small positioning devices to the bodies of animals to better understand what they do and where. It is relatively well known that bats, dolphins, whales, and some other animals use echolocation to recognize positioning information. Bio-logging is different in that it does not use sound emitted from the animals, but uses signals sent from transmitters attached to the animals. Argos, a system using satellites, is the most common wildlife tracking system used for bio-logging. Here, the Doppler curve, for which the frequency shifts from positive to negative due to the Doppler effect, corresponds to each animal location. This curve is used to compute animal positions. Recently devices equipped with GPS functions that can even use virtual ultrasonics have been developed. There are expectations for advances in bio-logging based on new survey systems that combine such devices with the Argos system. Apparently recorders can be attached to whales using suction discs as whale epidermis is rather sleek. Records taken using Argos indicate that whales dive to depths of between 1,000 and 2,000 m depending on the species. I wonder if whales at such sea depths could be located using echolocation functions. Diversity associated with the development and progress of engineering research and engineering technology is important. Originality often comes from such diversity. Recently in the field of science and technology, there have been books and papers focusing on such topics as the ‘‘essence of engineering.’’ The Japan Society of Ultrasonics in Medicine was created through a natural fusion of engineering research and technologies from various fields, along with research in medical science fields. There is no doubt that the utilization of close ties between engineering and medical science, a strength of this academic society, can help improve the quality of this journal and make direct and indirect contributions to both medical circles and society. Contributions to this journal from various countries overseas are trending higher with a striking increase in the number of original papers and case reports contributed to the English version of this society’s journal. In the midst of such progress, I am grateful to be involved with this academic journal as an area editor.

JSUM ultrasound elastography practice guidelines: breast.

Ten years have passed since the first elastography application: Real-time Tissue Elastography™. Now there are several elastography applications in existence. The Quality Control Research Team of The Japan Association of Breast and Thyroid Sonology (JABTS) and the Breast Elasticity Imaging Terminology and Diagnostic Criteria Subcommittee, Terminology and Diagnostic Criteria Committee of the Japan Society of Ultrasonics in Medicine (JSUM) have advocated breast elastography classifications for exact knowledge and good clinical use. We suggest two types of classifications: the technical classification and the classification for interpretation. The technical classification has been created to use vibration energy and to make images, and also shows how to obtain a good elastic image. The classification for interpretation has been prepared on the basis of interpretation of evidence in this decade. Finally, we describe the character and specificity of each vender equipment. We expect the present guidelines to be useful for many physicians and examiners throughout the world.

Current developments and clinical applications of bubble technology in Japan: a report from 85th Annual Scientific Meeting of The Japan Society of Ultrasonic in Medicine, Tokyo, 25-27 May, 2012

The potentials of bubble technology in ultrasound has been investigated thoroughly in the last decade. Japan has entered as one of the leaders in bubble technology in ultrasound since Sonazoid (Daiichi Sankyo & GE Healthcare) was marketed in 2007. The 85th Annual Scientific Meeting of The Japan Society of Ultrasonics in Medicine held in Tokyo from May 25 to 27, 2012 is where researchers and clinicians from all over Japan presented recent advances and new developments in ultrasound in both the medical and the engineering aspects of this science. Even though bubble technology was originally developed simply to improve the conventional ultrasound imaging, recent discoveries have opened up powerful emerging applications. Bubble technology is the particular topic to be reviewed in this report, including its mechanical advances for molecular imaging, drug/gene delivery device and sonoporation up to its current clinical application for liver cancers and other liver, gastrointestinal, kidney and breast diseases.

Transmission electron microscopy study on the effects of the ultrasound contrast agent Levovist on hepatic cells.

The Ultrasound Equipment and Safety Committee of The Japan Society of Ultrasonics in Medicine performed experiments to confirm whether contrast-enhanced ultrasonography damages liver cells. Rats were injected with 0.1ml of 300mg/ml ultrasound contrast agent (UCA). Diagnostic ultrasound pulses with a center frequency of 6MHz and a mechanical index of 1.9 were applied to rat livers with a water bag as a coupler to maintain a distance of 2-6cm between the ultrasound probe surface and the liver. Contrast-enhanced ultrasonography was carried out for 10s to visualize the entire liver. Then, specimens of liver tissue were fixed using two types of fixation: immersion and perfusion fixation. Although some variations were found in electron micrographs of liver tissue fixed using immersion fixation, none of three blinded readers found any significant differences between micrographs of liver tissue from rats receiving UCA with sonication and those from sham-treated control rats. Changes observed were not thought to be group-specific but instead due to differences between individual rats. When the livers were fixed using perfusion fixation and the hepatic vein was cut after injection of physiological saline for perfusion, a large number of vacuoles ≥2μm in diameter were observed. This finding suggested that hepatic cell damage observed in this study was caused by high perfusion pressure during the liver fixation process rather than by sonication with UCA. Blinded readings of electron micrographs showed no clear evidence that the use of Levovist in ADI mode ultrasonography causes significant damage to liver tissue.

Assignment of an impact factor to our journal

This year an impact factor has been assigned to the official English journal of the Japan Society of Ultrasonics in Medicine. We are delighted that our journal can be internationally recognized as important one in this academic field. We would like to thank you all for your support. In a given year, the impact factor of a journal is the average number of citations of the papers published in the journal during the two preceding years. In our case, the 2010 impact factor of our journal would be calculated as follows: 2010 impact factor 1⁄4 A=B

Differential diagnosis of breast mass image-forming lesions based on changes in depth-width ratio and internal echo intensity by hand-held probe compression.

Regarding mass image-forming lesions, the 2005 Guidelines for Ultrasonic Diagnosis of Breast Diseases, published by the Japan Society of Ultrasonics in Medicine (JSUM), includes the evaluation of tumor compressibility, which is visually assessed by the degree of deformation caused by applying external pressure to the tumor. However, this is only a subjective estimation under real-time observation; consequently, quantitative evaluation of tumor deformation and the percentage change in internal echo intensity was attempted based on changes in the depth-width ratio and in the internal echo intensity on hand-held probe compression. We evaluated the usefulness of these measurements in the differential diagnosis of benign and malignant tumors. The subjects were 139 patients (89 benign and 50 malignant cases) who underwent breast ultrasonography with a 10-MHz (from 4-to 10-MHz) linear probe. The deformation index (D.I.) of the tumor was defined as: [1 - (depth-width ratio with 3.0 ± 0.6-kg-weighted compression)/(depth-width ratio without compression)] × 100 (%). The rate of change in internal echo intensity was defined as the echo intensity with compression divided by the echo intensity without compression × 100 (%). There was a significant difference in the D.I. between benign lesions (35.5% ± 14.7%) and malignant lesions (15.4% ± 6.2%) (P < 0.001). The cut-off ratio in differentiating benign from malignant lesions was approximately 25%. The rate of change in echo intensity of benign lesions (149.7% ± 34.3%) was significantly higher than that of malignant lesions (122.9% ± 19.9%) (P < 0.001). Using an electronic linear probe, quantitative indexes including the D.I. and the rate of change in internal echo intensity could be obtained with the help of a weight meter, and could prove effective for the differential diagnosis of breast mass-image forming lesions.

Ultrasonic diagnosis in orthopedics

Ultrasonics in medicine and especially ultrasonics in orthopedics are an essential enrichment of our ways of making a diagnosis. The development of modern diagnosis instruments in addition to the systematic research of the skeletal system and soft tissues have made it possible that this method can now also be employed in the special field of orthopedics. That doesn't mean that other imaging methods should be given up but rather that this new way of imaging should be seen as a completion and a screening method for the other procedures. Because of the easiness of applying ultrasonics there is also the danger of overestimating the extent to which this method can be used and the danger of misinterpreting findings because of a lack of knowledge. Both risks should be kept in mind when using ultrasonics so that this harmless method doesn't became dangerous to the patients after all.

1145: Education, guidelines and accreditation

The need for education, guidelines and accreditation is fundamental in providing high quality ultrasonic imaging at both national and international levels. The increasing clinical reliance on breast ultrasound has resulted in societies and organizations providing educational programs, developing guidelines for examinations and interventional procedures and establishing accreditation programs. The International Breast Ultrasound School (IBUS) provides educational programs to improve the standards of practice of breast ultrasound. Programs consisting of lectures and interactive workshops are held in conjunction with scientific meetings or as a stand-alone curriculum over a one to three d period. In response to the increased need for education and accreditation in breast ultrasound, IBUS is providing a new series of five d residential courses in Ferrara, Italy, in association with the University of Ferrara. These international courses satisfy continuing medical education requirements, and participants will be assessed on their competency. The published IBUS guidelines form the basis of recommendations required to become proficient in ultrasonic breast imaging. The experience necessary to achieve accuracy and confidence is based on the examination and reporting of a minimum of 500 breast cases in a multidisciplinary environment, and in order to become proficient with interventional techniques at least 50 procedures must be undertaken. The German Society for Ultrasound in Medicine (DEGUM) has established guidelines for training courses based on a three level structure consisting of basic, advanced and final components. Each component is a two day course supervised by an accredited course director with five years experience in breast ultrasound and has performed at least 5000 breast ultrasound examinations. Course participants receive a certificate on completing theoretical and practical training extending over a period of not less than 9 months. The American Institute of Ultrasound in Medicine (AIUM) has produced breast ultrasound accreditation guidelines to encourage practices to meet or exceed recognized standards in a number of practice-related areas. Individuals must participate in continuing medical education programs, and practices must demonstrate that examination findings and final reports are monitored. The brochure “AIUM Standard for the Performance of Breast Ultrasound Examinations” documents the minimum criteria for high quality breast ultrasound examinations. The American College of Radiology (ACR) has developed a number of accreditation programs. The “Breast Ultrasound Accreditation Program” evaluates the qualification of personnel, equipment performance, effectiveness of quality control measures, and quality of clinical images. Accreditation can be obtained for ultrasonic imaging alone or in combination with ultrasound-guided biopsy procedures when these are included in the facility. Individuals are required to fulfil qualification criteria, and undertake continuing medical education. The Japanese Society of Ultrasonics in Medicine (JSUM) and the Japan Association of Breast and Thyroid Sonology (JABTS) have published guidelines describing the diagnostic criteria for diffuse and discrete breast lesions based on their long term experience. Recently, the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) published the “Guidelines for Ultrasound Guided Breast Biopsy”, and this document outlines the clinical role of the available percutaneous needle biopsy methods.

The Seventh Congress of the Asian Federation of Societies for Ultrasound in Medicine and Biology and the 77th Annual Scientific Meeting of the Japan Society of Ultrasonics in Medicine.

The Seventh Congress of the Asian Federation of Societies for Ultrasound in Medicine and Biology and the 77th Annual Scientific Meeting of the Japan Society of Ultrasonics in Medicine.

Ultrasonic Measurement of Minute Displacement of Object Cyclically Actuated by Acoustic Radiation Force

Recently, several researchers have investigated the potential of the use of acoustic radiation force for imaging the mechanical properties of tissue. However, these methods have some problems as to safety and the spatial resolution. Therefore, an alternative ultrasonic remote actuation and measurement method is proposed in this paper, in which the intensity of the applied continuous ultrasonic wave is suppressed to be lower than the safety guideline (1 W/cm2) recommended by the Japan Society of Ultrasonics in Medicine (JSUM). A minute displacement with amplitude of less than 1 µm is cyclically generated by the radiation force with a low frequency Δf of several hertz. For simultaneous measurement of the minute displacement, cyclic radiation force is applied intermittently by maintaining its envelope waveform of the low-frequency component of Δf Hz. At the same time, an ultrasonic correlation-based method, namely, the phased tracking method, is employed to measure the minute displacement. In basic experiments, the minute displacement of several micrometers was generated in silicone rubber by applying radiation force, and it was successfully measured by the phased tracking method.

From A-mode Echoencephalography to Intraoperative Monitoring

My experiences and episodes on clinical application of ultrasound for about thirty years were described.About the development of A-mode echoencephalography in Japan, the establishement of Japan Soiety of Ultrasonics in Medicine, the beginning of intraoperatieve use of B-mode in brain surgery in ultrasonic medicine in Japan, and other affairs followed about ultrasonic medicine in my life, were introduced here briefly.

Book reviewInvestigative Ultrasonology. 1. Technical Advances. Ed. by HillC. R. and AlvisiC., pp. ix + 165, 1980 (Pitman Medical, Tunbridge Wells), £14·95. ISBN 0–272–79575–5

This well-produced volume comprises the proceedings of three workshops and a review lecture which constituted part of the Third European Congress on Ultrasonics in Medicine, held at Bologna in 1978. There are some 30 contributions, divided into sections (one per workshop): automatic and computer-aided sonography (nine papers); living tissue identification and movement analysis (nine papers); and dosimetry control of ultrasound and standardization of equipment (seven papers). A useful feature of the text is the inclusion of the salient points of the discussions which took place. For the second section these are collectively summarized, while for the last section the summary is included at the end of each of the papers that were presented. The topics and contributors appear to have been selected by the workshop chairman with the result that each workshop presents a mixture of summarized new developments and superficial reviews.

Third European Congress on Ultrasonics in Medicine—Bologna, Italy, 1–5 October 1978

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