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Objectives: To assess whether meal or water intake may affect the measurement of the ultrasound (US) attenuation coefficient (AC) imaging, a parameter that is directly related to liver fat content., Methods: The study was performed in two centers (Italy and USA). AC was obtained using the ATI algorithm implemented in the Aplio i-series US systems (Canon Medical Systems, Japan) by one operator at each center. Measurements were performed at baseline and 5, 15, 30, 45 minutes after drinking 500 mL of water (group 1), or 30, 45, 60, 90, 120 minutes after eating a meal of about 600 kcal (group 2). Multilevel generalized estimating equations for repeated measures were used for the statistical analysis to consider the clustered nature of the data., Results: Twenty-six individuals were enrolled: 11 (10 females; age, 43.7 ± 12.5 years) in Italy and 15 (10 females; age, 60.7 ± 6.3 years) in USA. At B-mode US, 10 (38.5%) had liver steatosis. The baseline AC values, in decibel/centimeter/megahertz, were 0.64 (0.12) in group 1 and 0.66 (0.13) in group 2. There was not any significant difference in AC values at every time-point after water or meal intake either in group 1 or group 2. This result did not change including sex, age, and skin-to-liver capsule into the models., Conclusions: The measurement of the AC, which is a biomarker of liver steatosis, does not require a fasting state and drinking water does not affect the result., (© 2024 American Institute of Ultrasound in Medicine.)

Objectives: The primary aim was to estimate the influence of various depths on ultrasound attenuation coefficient (AC) of multiple vendors in the liver. The secondary aim was to evaluate the impact of region of interest (ROI) size on AC measurements in a subset of participants., Methods: This Institutional Review Board (IRB)-approved Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study was carried out in two centers using AC-Canon and AC-Philips algorithms and extracting AC-Siemens values from ultrasound-derived fat fraction algorithm. Measurements were performed positioning ROI upper edge (3 cm size) at 2, 3, 4, 5 cm from the liver capsule with AC-Canon and AC-Philips and at 1.5, 2, 3 cm with Siemens algorithm. In a subset of participants, measurements were obtained with 1 and 3 cm ROI size. Univariate and multivariate linear regression models and Lin's concordance correlation coefficient (CCC) were used for statistical analysis as appropriate., Results: Three different cohorts were studied. Sixty-three participants (34 females; mean age: 51 ± 14 years) were studied with AC-Canon, 60 (46 females; mean age: 57 ± 11 years) with AC-Philips, and 50 (25 females; 61 ± 13 years) with AC-Siemens. There was a decrease in AC values per 1 cm increase in depth in all. In multivariable analysis, the coefficient was -0.049 (-0.060; -0.038 P < .001) with AC-Canon, -0.058 (-0.066; -0.049 P < .001) with AC-Philips and -0.081 (-0.112; -0.050 P < .001) with AC-Siemens. AC values with 1 cm ROI were significantly higher than those obtained with 3 cm ROI at all depths (P < .001) but the agreement between AC values obtained with different ROI size was excellent (CCC 0.82 [0.77-0.88])., Conclusions: There is depth dependence in AC measurement that affects results. A standardized protocol with fixed ROI's depth and size is needed., (© 2023 The Authors. Journal of Ultrasound in Medicine published by Wiley Periodicals LLC on behalf of American Institute of Ultrasound in Medicine.)

Purpose: To determine the natural history and necessity of long-term follow-up of renal masses that do not demonstrate enhancement on contrast-enhanced ultrasound (CEUS)., Methods: This retrospective single-center study was approved by our local IRB and is HIPAA compliant. Exactly 405 patients with 620 non-enhancing renal masses on CEUS from a previously reported study were followed for up to 10 years. Techniques and equipment are described in the original manuscript. Patient charts and imaging studies were reviewed for the change in features. There were 117 (18.6%) patients lost to follow-up leading to 341 patients with 512 lesions. The lesion size, patient age, number of lesions per patient, and Bosniak class assigned at the initial examination was recorded., Results: Mean patient age was 66 ± 12.6 years (range 17-95 years). Average time of follow-up was 58.9 ± 41.7 months (range 1-207 months). There was a mean of 1.5 ± 1.0 lesions per patient (range 1-7 lesions). Lesion size was 24.9 ± 18.2 mm (range 3-161 mm). There were 276 (53.9%) patients with >5-year follow-up and 78 (15.2%) patients with >10-year follow-up. The probability of change within 5 years was 0% (95% CI: 0-0.37 per 100PY) and 10 years 0% (95% CI: 0.0-0.18 per 100PY). Two lesions (0.4%) resolved by 60 months. Five lesions (1.0%) decreased in size. Four lesions (0.8%) increased in size >20% during the follow-up period but remained benign on subsequent imaging., Conclusion: Any non-enhancing renal mass on CEUS can be classified as benign., (© 2023 The Authors. Journal of Ultrasound in Medicine published by Wiley Periodicals LLC on behalf of American Institute of Ultrasound in Medicine.)

Objectives: To compare the estimates of attenuation coefficient (AC) for liver fat quantification between 2 Ultrasound systems and to evaluate the quality measure of a pre-released software., Methods: AC were obtained in 30 participants in this single-center IRB-approved, HIPAA compliant study. Images were obtained on the Philips Epiq Elite system using experimental software and the Canon Medical Systems Aplio i800 with released software. Five AC measurements were taken and the median and IQR/M were calculated. Region of interest placement was based on a confidence map. ROI was at the same depth and size for each system. The concordance was estimated using the Lin's concordance correlation coefficient (CCC), the r Pearson's correlation coefficient, the bias-correction factor (Cb), and the Bland-Altman method., Results: The ACs varied from 0.45 to 1.0 dB/cm/MHz for the Philips system and 0.30 to 0.96 dB/cm/MHz for the Canon system. The CCC (95% CI) was 0.792 (0.666-0.918), Pearson's r was 0.839 with Cb of 0.944, and the mean difference was 0.03 (-0.101; 0.162) suggesting the 2 methods are considered to be in agreement. Based on a Philips confidence map to determine the best location for performing the measurements, a depth of 3.5 to 4.0 cm from the liver capsule was determined, which might be significantly different than that of the Canon system., Conclusions: Estimation of the AC of the 2 systems showed a high agreement, that is, a similar trend. Assessment of the placement of the measurement box based on the quality of the measurement might be different between the 2 systems., (© 2021 American Institute of Ultrasound in Medicine.)

Ocular ultrasound is an invaluable tool for the evaluation of the eye and orbit. However, the eye and orbit are potentially sensitive to the thermal and mechanical effects of ultrasound. When performing B-mode imaging, dedicated ocular settings should be used. If these settings are not available, limiting the acoustic output to Food and Drug Administration (FDA) recommended maximum levels is strongly advised. Especially important is the acoustic output in spectral (pulsed) and color Doppler modes, which can exceed the FDA's maximum recommended levels for the eye. Adjusting settings to decrease acoustic output and limiting the time of the examination should be done when performing a Doppler examination. The acoustic output of shear wave elastography is significantly higher than FDA guidelines for the eye and should be considered experimental., (© 2021 American Institute of Ultrasound in Medicine.)

Ultrasound is very effective in performing procedures and assessment of complications in peritoneal dialysis. The ultrasound examination can be applied for preoperative assessment, during the peritoneal catheter placement, for the detection and monitoring of infection, as well as for the evaluation of the catheter malfunction. Despite being not only a cost- and time-saving technique but also a bedside procedure, ultrasonography remains an underrated clinical tool in the field of peritoneal dialysis. This publication wants to explain and reinforce the clinical utility of US in PD and to expand the diagnostic equipment for the clinician., (© 2021 American Institute of Ultrasound in Medicine.)

Objectives: The BI-RADS classification provides a standardized way to describe ultrasound findings in breast cancer diagnostics. However, there is little information regarding which BI-RADS descriptors are most strongly associated with malignancy, to better distinguish BI-RADS 3 (follow-up imaging) and 4 (diagnostic biopsy) breast masses., Methods: Patients were recruited as part of an international, multicenter trial (NCT02638935). The trial enrolled 1294 women (6 excluded) categorized as BI-RADS 3 or 4 upon routine B-mode ultrasound examination. Ultrasound images were evaluated by three expert physicians according to BI-RADS. All patients underwent histopathological confirmation (reference standard). We performed univariate and multivariate analyses (chi-square test, logistic regression, and Krippendorff's alpha)., Results: Histopathologic evaluation showed malignancy in 368 of 1288 masses (28.6%). Upon performing multivariate analysis, the following descriptors were significantly associated with malignancy (P < .05): age ≥50 years (OR 8.99), non-circumscribed indistinct (OR 4.05) and microlobulated margin (OR 2.95), nonparallel orientation (OR 2.69), and calcification (OR 2.64). A clinical decision rule informed by these results demonstrated a 97% sensitivity and missed fewer cancers compared to three physician experts (range of sensitivity 79-95%) and a previous decision rule (sensitivity 59%). Specificity was 44% versus 22-83%, respectively. The inter-reader reliability of the BI-RADS descriptors and of the final BI-RADS score was fair-moderate., Conclusions: A patient should undergo a diagnostic biopsy (BI-RADS 4) instead of follow-up imaging (BI-RADS 3) if the patient is 50 years or older or exhibits at least one of the following features: calcification, nonparallel orientation of mass, non-circumscribed margin, or posterior shadowing., (© 2021 The Authors. Journal of Ultrasound in Medicine published by Wiley Periodicals LLC on behalf of American Institute of Ultrasound in Medicine.)

In adults with chronic liver diseases, ultrasound and magnetic resonance shear wave elastography (SWE) can replace liver biopsy in several clinical scenarios. Several guidelines on the use of ultrasound SWE for the adult population have been published. However, the number of publications in the pediatric population is limited, and available guidelines on SWE do not specifically address pediatric chronic liver diseases. In this article, we review the literature on the use of SWE for pediatric chronic liver diseases and provide expert opinion on how to use SWE, both ultrasound and magnetic resonance techniques, in the pediatric population., (© 2020 American Institute of Ultrasound in Medicine.)

Objectives: There are conflicting results in the literature on the use of shear wave elastography of the kidney parenchyma to determine whether renal stiffness values are related to a disease process. This study was conducted to evaluate the raw data from 3 ultrasound systems and determine whether adequate displacement curves are obtained to accurately estimate shear wave speeds., Methods: Shear wave elastography was performed on 5 healthy volunteers with 3 ultrasound systems. The raw data were collected and evaluated for the shear wave propagation quality to determine whether accurate estimates of renal shear wave speeds could be determined., Results: Results from the 3 machines demonstrate that accurate shear wave displacement curves are not obtained with renal elastography on existing systems (as of June 2018). One vendor has recently released software that appears to acquire accurate shear wave displacements., Conclusions: Elastographic studies performed on the kidney to date are likely to be inaccurate. A new algorithm that appears to acquire accurate shear wave displacements in the kidney has been developed. Additional studies are needed to confirm that the new algorithm provides accurate clinical results. This study demonstrates that although the system provides a shear wave speed, it is important to confirm the accuracy of that number by evaluating the raw data., (© 2019 by the American Institute of Ultrasound in Medicine.)

Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them., (© 2019 by the American Institute of Ultrasound in Medicine.)

Objectives: There is a significant learning curve in strain elastography. Uniform appropriate levels of stress must be applied for accurate elastograms. If the stress is not applied appropriately, inaccurate results will be obtained, particularly when strain ratios are being estimated. This paper describes a new technique which allows the real-time visualization of the applied stress with a color-coded stress map. The potential use of this map is discussed., Methods: Ten patients (5 breast, 5 thyroid) and phantoms were scanned using the stress map. The stress applied was varied and the resultant change in the strain image evaluated., Results: The stress map was able to document if appropriate stress was applied when performing strain elastography. When inappropriate stress was applied or physiological process effected the strain image the stress map demonstrated the areas of inaccurate measurements in the stress map., Conclusions: The display of a stress map that depicts the degree and uniformity of applied stress would be helpful both for training of the appropriate technique, for confirming that the elastogram is appropriate for evaluation, and that strain ratio estimates are accurate., (© 2019 by the American Institute of Ultrasound in Medicine.)

There are 3 methods of interpreting breast strain elastography: the elastographic-to-B-mode length ratio (E/B), a 5-point color scale (5P), and the strain ratio (SR). This meta-analysis assessed which method is superior to the others. A systematic search of the medical literature was performed in July 2017. Studies were eligible for inclusion if they fulfilled the following criteria: (1) had biopsy-proven or long-term stability as the reference standard; (2) used either the E/B, 5P, or SR to interpret results; and (3) had at least 50 cases. A total of 220 records were retrieved; 60 full-text articles were examined, and 46 were included in the meta-analysis. Publication years ranged from 2007 and 2017. The quality of studies was generally high. The mean age of women was 48 years; 12,398 lesions (4242 malignant) were analyzed. For the 5P method, the sensitivity was 77%; specificity, 87%; positive likelihood ratio (LR), 5.3; and negative LR, 0.24. For the SR method, sensitivity was 87%; specificity, 81%; positive LR, 4.8; and negative LR, 0.16. For the E/B method, sensitivity was 96%; specificity, 88%; positive LR, 7.1; and negative LR, 0.03. Of the 3 methods, the E/B had the highest sensitivity, and the E/B and 5P had the highest specificity. With a negative LR of 0.03, the E/B method can downgrade lesions with a pretest probability of 50% to a 2% probability of malignancy., (© 2018 by the American Institute of Ultrasound in Medicine.)

Objectives: To compare the agreement and interobserver variability of diagnostic handheld ultrasound (US) and a single volume on an automated breast volume scanner (ABVS) and to determine whether there was a significant difference if the ABVS was used by a sonographer or mammographic technologist., Methods: Ninety patients scheduled for diagnostic US examinations were randomized to either handheld US or the ABVS first. The AVBS was randomized between a sonographer and a mammographic technologist performing the study. The studies were blinded, randomized, and read by 2 radiologists. The lesion with the highest Breast Imaging Reporting and Data System (BI-RADS) score was used in the analysis. Final diagnoses were made by core biopsy or follow-up for 2 years. Lesions included 9 malignant and 81 benign., Results: The 90 patients had a mean age ± SD of 53.1 ± 16.3 years. The κ value for agreement between the ABVS and handheld US was 0.831 (95% confidence interval, 0.744-0.925), whereas the global agreement for a 7-point BI-RADS score was 0.488 (0.372-0.560). The agreement between the ABVS and handheld US was nearly the same when the ABVS was used by a mammographic technologist (κ = 0.858 [0.723-0.963]) or sonographer (κ = 0.803 [0.596-1.000]; P = .47). The areas under the receiver operating characteristic curves for characterization by the ABVS were 0.91 (0.84-0.96) for reader 1 and 0.91 (0.83-0.96) for reader 2; those for handheld US were 0.91 (0.84-0.96) for reader 1 and 0.83 (0.74-0.90) for reader 2, with no statistical difference. The agreement based on pathologic images was κ = 0.831 (0.718-0.944); for handheld US, κ = 0.795 (0.623-0.967); and for the AVBS, κ = 0.869 (0.725-1.000)., Conclusions: Performing a single-view diagnostic ABVS examination has good agreement with a handheld diagnostic US workup. There is no difference if the ABVS is used by a sonographer or mammographic technologist., (© 2017 by the American Institute of Ultrasound in Medicine.)

With the recent Food and Drug Administration approval of Lumason (sulfur hexafluoride lipid-type A microsphere, Bracco Diagnostics Inc, Monroe Township, NJ) for contrast-enhanced ultrasound (CEUS) to characterize focal liver lesions in both adult and pediatric patients, widespread use of CEUS is expected in the United States. This paper provides guidance in setting up a CEUS program, and reviews the practical details that will need to be instituted in a standard ultrasound department to provide both safe and efficient use of CEUS. A review of the indications, contraindications, adverse events, instructions for performing the exam, and image interpretation are discussed., (© 2017 by the American Institute of Ultrasound in Medicine.)

Objectives: To evaluate the effect of precompression on power Doppler visualization of blood flow in breast masses., Methods: This Institutional Review Board-approved and Health Insurance Portability and Accountability Act-compliant study evaluated 30 patients with breast masses (16 benign and 14 malignant) undergoing ultrasound-guided breast biopsy. A computational mathematics program was used to calculate the number of color pixels in a region of interest at various degrees of compression of the breast by the transducer. The amount of precompression was calculated as previously described. The percentage of color pixels compared to minimal compression was plotted against the percentage of precompression. The amount of precompression needed to decrease the number of color pixels by 50% and 100% was calculated. The differences between benign and malignant lesions were compared., Results: The mean percentages of precompression ± SD needed to decrease the number of color voxels by 50% in were 15.9% ± 6.43% (range, 8%-30%) for benign lesions and 14.0% ± 4.17% (range, 8%-20%) for malignant lesions (P = .35). The percentages of precompression needed to decrease the number of color pixels by 100% in were 34.7% ± 12.33% (range, 23%-62%) for benign lesions and for malignant lesions 26.7% ± 3.89% (range, 18%-31%), which were statistically significant (P = .027)., Conclusions: The amount of precompression normally used when obtaining B-mode images can substantially decrease the number of color voxels on power Doppler sonography. When performing quantitative work on Doppler evaluation of breast lesions, precompression needs to be controlled., (© 2016 by the American Institute of Ultrasound in Medicine.)

Sonographic elastography has been shown to be a useful imaging modality in characterizing breast lesions as benign or malignant. However, in preliminary research, mastitis has given false-positive findings on both strain and shear wave elastography. In this article, we review the findings in mastitis with and without abscess formation on both strain and shear wave elastography. The elastographic findings in all cases were suggestive of a malignancy according to published thresholds. In cases of mastitis with abscess formation, there is a characteristic appearance, with a central very soft area (abscess cavity) and a very stiff outer rim (edema and inflammation). This appearance should raise the suspicion of mastitis with abscess formation, since these findings are rare in breast cancers.

Objectives: The purpose of this study was to determine whether the elasticity imaging/B-mode ratio on strain elastography can predict breast cancer tumor grades., Methods: A retrospective review of patients with breast lesions who underwent strain elastography and had a diagnosis of breast cancer by image-guided or surgical biopsy was performed. The axis of the maximum elastographic dimension was compared to the B-mode dimension to form an elasticity imaging/B-mode ratio. Lesions were categorized according to their pathologic type, including atypical ductal hyperplasia (ADH), mucinous or colloid cancer, ductal carcinoma in situ (DCIS), grade I invasive ductal carcinoma (IDC), grade II IDC, grade III IDC, invasive lobular carcinoma (ILC), and lymphoma. The mean elasticity imaging/B-mode ratio of each tumor type was calculated. The elasticity imaging/B-mode ratio of the tumor was compared to the tumor type by Kruskal-Wallis and Tukey-Kramer tests (lymphoma and ADH excluded because of small numbers)., Results: Tumor grades included lymphoma (n = 3), ADH (n = 2), mucinous cancer (n = 11), DCIS (n = 19), IDC (grades I-III; n = 200), and ILC (n = 31). The mean elasticity imaging/B-mode ratio varied with increasing tumor grade. Tumor grades could not have been selected at random from one population (P < .0001, χ(2) test). Invasive lobular carcinoma and grade III IDC were statistically different from mucinous or colloid cancer, DCIS, and grade I and II IDC., Conclusions: The elasticity imaging/B-mode ratio on strain elastography is related to the tumor grade.

Objectives: Elastography of the breast is a new technique for characterization of breast lesions. The reproducibility of elastographic techniques has been questioned. Precompression is known to effect elastographic results. This study determined the effect of precompression on clinical images and proposes a method to semiquantify the amount of precompression applied., Methods: Ten patients with different breast tissue types were evaluated with shear wave and strain elastography with varying amounts of precompression. The changes in the shear wave speed and images were documented. A semiquantitative method for determining the amount of precompression applied is presented. The reproducibility of the technique was determine by repeated measurements by 3 sonographers., Results: Precompression substantially changes the elastographic results of patient images on both strain and shear wave elastography. Fat can have the same elasticity as cancer with clinically possible amounts of precompression. The proposed method for determining the amount of precompression applied has variability of less than 10%, which is within the error of the technique and would not affect clinical results. Four zones of precompression are identified, which are useful for explaining the effects of precompression on both strain and shear wave imaging., Conclusions: Precompression is a substantial factor in obtaining accurate results with elastography. A proposed simple, easily applied technique can be used to semiquantify the amount of precompression applied. Precompression should be minimized in obtaining breast clinical images.

Breast elastography is a new sonographic technique that provides additional characterization information on breast lesions over conventional sonography and mammography. This technique provides information on the strain or hardness of a lesion, similar to a clinical palpation examination. Two techniques are now available for clinical use: strain (compression-based elastography) and shear wave elastography. Initial evaluation of these techniques in clinical trials suggests that they may substantially improve the characterization of breast lesions as benign or malignant. This improvement may substantially reduce the number of benign biopsies performed. Elastography can be performed by several methods and is now available from several manufactures. This article reviews the basics of this technique, how to perform the examination, image interpretation, and artifacts. Although easy to perform, technique is critical to obtain adequate images for interpretation. This primer will highlight the technique and point out common pitfalls.

Objectives: The purpose of this study was to determine the sensitivity and specificity of real-time compression elasticity imaging in characterizing breast lesions as benign or malignant., Methods: A cohort of 578 women scheduled for sonographically guided biopsy of breast lesions were recruited from 6 sites under an Institutional Review Board-approved protocol. All participants received an elastogram, which displayed both the B-mode and elasticity images in real time. The longest dimensions of the lesion on the B-mode and elasticity imaging were measured. An elasticity imaging/B-mode ratio of at least 1.0 was considered positive for malignant lesions. The reference standard was based on biopsy., Results: A total of 635 lesions were imaged and biopsied. There were 222 (35%) malignant or borderline lesions and 413 (65%) benign lesions. The benign lesions were either cystic (145 [35%]) or solid (268 [65%]). Of the 222 malignant lesions, 219 had an elasticity imaging/B-mode ratio of at least 1.0. Of the 413 benign lesions, 361 had an elasticity imaging/B-mode ratio less than 1.0. These results corresponded to overall sensitivity of 98.6% and overall specificity of 87.4%. Individual site sensitivities ranged from 96.7% to 100% whereas specificities ranged from 66.7% to 95.4%., Conclusions: Elasticity imaging has high sensitivity in characterizing malignant lesions of the breast. Variability in specificity between sites and sonographers is possibly due to individual technique differences in performing elastography and measuring lesions. Further work in standardizing the technique is required.

Objective: Both sonography and scintigraphy have been used to evaluate gallbladder function with the use of sincalide (cholecystokinin [CCK]). However, the reported ejection fractions (EFs) for the two modalities are not the same. The techniques measure slightly different parameters. This study directly compared both techniques performed simultaneously on the same participants., Methods: Twenty healthy volunteers were evaluated with sonography and scintigraphy to estimate the gallbladder EF simultaneously. The gallbladder EF was calculated at 5-minute intervals for 1 hour., Results: The mean EFs +/- SD were 66.3% +/- 20% and 49% +/- 29% for sonography and scintigraphy, respectively. The mean times to the peak EF were 38 +/- 12 and 33 +/- 9 minutes for sonography and scintigraphy. An average time of 34 minutes was noted after radiopharmaceutical injection before CCK administration for the scintigraphic studies. The earliest time to the peak EF for sonography was 15 minutes, and the latest time to the peak EF was 60 minutes (mode, 40 minutes); for scintigraphy, the earliest and latest times were 15 and 50 minutes (mode, 30 minutes), respectively. One participant could not be evaluated secondary to nonfilling of the gallbladder on scintigraphy. There was wider variability of the gall-bladder EF with scintigraphy than sonography., Conclusions: Scintigraphy estimated a lower EF than sonography, had wider EF variability than sonography, and required additional time (>30 minutes more) to complete the study. Scintigraphy could not be performed in 5% of the participants because of nonfilling of the gallbladder. The use of sonography to estimate the gallbladder EF is less time-consuming and less costly. With these techniques, the range of normal gallbladder EFs should be adjusted for the technique used.