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Background & Aims: Ultra-microangiography (UMA) is a novel Doppler technique with optimized wall filtering that provides high sensitivity to low-velocity blood flows and optimized visualization of microcirculation. The aim of this pilot study was to compare intestinal vascularization assessed by color Doppler signals (CDS) and UMA. Methods: We investigated intestinal vascularization using UMA and CDS in 13 patients with confirmed inflammatory bowel disease (IBD). A cohort of 28 patients without structural bowel disease served as the control. Results: Microcirculation and dysregulated microcirculation in patients without and with inflammatory bowel disease can be visualized and quantified using UMA. In 83 % of IBD patients and 76% of non-IBD patients, a high resolution of intestinal perfusion could be achieved using UMA. Conclusions: To the best of our knowledge, this is the first study to investigate intestinal vascularization using UMA in patients with and without structural bowel disease. Quantification and visualization of intestinal vascularization should be further investigated in prospective studies and could help guide our therapy of patients with IBD. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To test and initially describe a new handheld wireless ultrasound technique (TE Air) for clinical use. METHODS: In this pilot study, the new ultrasound device TE Air from Mindray was used to examine the hepatic and renal vessels of healthy volunteers for first impressions. The probe has a sector transducer with a frequency range of 1.8–4.5 MHz. The B-mode and color-coded doppler sonography (CCDS) scanning methods were used. A high-end device from the same company (Resona 9, Mindray) was used as a reference. The results were evaluated using an image rating scale ranging from 0 to 5, with 0 indicating not assessable and 5 indicating without limitations. RESULTS: Altogether, 61 participants (n = 34 female [55.7%], n = 27 male [44.3%]), age range 18–83 years, mean age 37.9±16.5 years) could be adequately studied using TE AIR and the high-end device. With one exception, the image quality score for TE Air never fell below 3 and had a mean/median scored of 4.97/5.00 for the B-mode, 4.92/5.00 for the color flow (CF) mode, and 4.89/5.00 for the pulse wave (PW) mode of the hepatic vein, 4.90/5.00 for the portal vein, 4.11/4.00 for the hepatic artery, and 4.57/5.00 for the renal segmental artery. A significant difference in the assessment of flow measurement of the hepatic artery and renal segmental arteries was found between TE AIR and the high-end device. CONCLUSIONS: TE Air represents a new dimension in point-of-care ultrasound via wireless handheld devices. Especially, its flow measurement ability offers a relevant advantage over other available handheld models. TE Air provides a formally sufficient image quality in terms of diagnostic significance. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the extent to which indeterminate lesions of the breast can be differentiated in the early and late phase after bolus injection of the ultrasound contrast medium Optison®. Materials and methods: Fifty female patients (mean age: 49 years) with a altogether 53 preoperatively impalpable indeterminate breast tumors, 20 fibroadenomas and 33 carcinomas, were examined by B-mode imaging and contrast medium-enhanced ultrasound with power Doppler (three patients had multifocal carcinomas). The tumors had a diameter of 5–15 mm (mean diameter: 9 mm). Histological confirmation was performed in all lesions by vacuum biopsies and/or surgical preparation. All examinations were performed with a multifrequency linear array probe (5–10 MHz, Logiq9 and Logiq 7, GE). Power Doppler (PD) and B-mode imaging as well as tissue harmonic imaging (THI) were employed. A bolus of 0.5 ml Optison® was injected intravenously and spreading of the contrast enhancement and washout in the tumors were followed for at least 20 minutes. A low mechanical index was chosen to avoid early destruction of the microbubbles. Maximum tumor size was measured and tumors vessels were evaluated in digital cine ultrasound sequences. Results: Without CM administration, 14 of 19 tumor lesions smaller than 10 mm could be distinguished better from the surrounding tissue with THI compared to fundamental B-mode imaging. Both benign (17/20) and malignant (30/33) tumors exhibited increased tumor marginal vessels or intratumoral vessels in the early phase after CM injection. A diffuse contrast medium accumulation was observed in the late phase (8–18 min, mean: 12 min) in 30 of 33 malignant tumors, but in none of the benign tumors. The diagnostic confirmation for this late enhancement was there with 90% for the malignant tumors. Conclusion: After intravenous bolus administration of Optison®, breast carcinomas appear to have a prolonged diffuse enhancement of central tumor vasularity in the late phase compared to an earlier marginal vascularity of fibroadenomas. [ABSTRACT FROM AUTHOR]

Improved detection and characterization of common focal liver lesions (FLL) are the main topics of the World Federation for Ultrasound in Medicine and Biology (WFUMB) guidelines on the use of contrast-enhanced ultrasound (CEUS). On state-of-the-art CEUS imaging, to create a library of rare FLL, especially concerning their atypical imaging characteristics, might be helpful for improving clinical diagnostic efficiency. In this review, we aim to summarize the ultrasound and CEUS features of rare benign FLL. Currently there are limited reports and images published. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The study aim was to investigate the use of a novel device, the Vscan Air™, for rapidly and effectively performing ultrasound in student teaching during the COVID-19 pandemic. MATERIAL AND METHODS: As part of the ultrasound practical course with integrated hands-on activity required by the regular medical curriculum, 100 medical students were instructed in the use of the Vscan Air™, including duplex mode. They then evaluated the quality of the ultrasound images obtained by the Vscan Air™ from previously selected organs. RESULTS: 100 students were interviewed (female n = 68, male n = 32; age >18 years n = 100). The rated image quality never fell below a mean of 3 for the examined organs and portal vein flow (liver 4,58; spleen 3,99; kidneys 4,29; aorta 4,16; Douglas/rectovesical space 4,14; portal vein 4,43; pancreas 3,53; Focused Assessment with Sonography for Trauma 4,38). Scores below 3 were found sporadically in ultrasounds of the spleen (n = 4), kidneys (n = 3), Douglas/rectovesical space (n = 2), and pancreas (n = 15). The liver was rated the lowest for 59 ratings. The portal vein was evaluated in 68 cases. The hepatic artery and hepatic veins could be also visualized in all 68 examinations. The aorta was evaluated in 62 cases. CONCLUSION: The Vscan Air™ technology offered adequate image quality and provided a new, fast and patient-oriented technique to support continuous ultrasound examinations and education of students, especially during a pandemic. Particularly noteworthy is the uncomplicated compliance with the required high level of hygiene. [ABSTRACT FROM AUTHOR]

Purpose: Abdominal thromboses are a poorly characterized thrombotic complication of COVID-19. The aim of this paper is to report multimodality ultrasound imaging findings of the abdomen in evaluation of thrombotic lesions in hospitalized patients with COVID-19. Patients & Methods: In this retrospective observational study, patients admitted to a single University Hospital from April 1, 2020 to April 30, 2022, who tested positive for COVID-19 and developed acute abdominal pain over the course of hospitalization were included. Abdominal ultrasound imaging studies performed in these patients were reviewed, including B mode ultrasound (BMUS), color-coded Doppler ultrasound (CCDS) and contrast enhanced ultrasound (CEUS). Thromboembolic findings on contrast enhanced computed tomography (CTA) were also recorded. Results: Finally, 13 cases of abdominal thrombosis in 226 with COVID 19 infections were included (mean age, 56.69±8.97 years; 10 men, 3 women). Thromboembolic events included: iliac thrombosis (n = 4), portal venous (PV) thrombosis (n = 3), superior mesenteric vein (VMS) thrombosis (n = 2), inferior vena cava (IVC) thrombosis (n = 5) and inferior mesenteric vein (VMI) thrombosis (n = 1). In all cases of abdominal thrombosis, during high resolution BMUS scan, intra-luminary hypoechogenic appositional thrombi could be detected. Meanwhile blood flow with reduced speed less than 20 cm/s could be observed by CCDS. High arterial flow speed was a sign of collateral flow changes with diffuse venous dilatation. On CEUS, changes of the microcirculation of the liver, spleen, kidneys or small bowel by infarctions or micro-emboli could be detected. In 3 cases of PV thrombosis and in 2 cases of IVC thrombosis, catheter interventions were successful performed for recanalization without relevant lumen reduction afterwards. In other cases, without interventional procedure, partial recanalization happened with venous flow speed over 15 cm/s and lumen reduction more than 50%. Conclusions: Our study highlights those thromboembolic complications can be seen in hospitalized patients with COVID-19. Multimodality ultrasound examinations is helpful for early and accurate diagnosis of these complications. [ABSTRACT FROM AUTHOR]

Background  Technical aspects are of utmost significance for an efficient execution in designing perforator flaps with high-resolution color-coded Duplex sonography (CCDS). The following study evaluates decisive factors for a successful microvessel examination conducted by the microsurgeon. Methods  Technical knowledge presented in this study was based on a series of more than 200 perforator flaps planned with CCDS. Flap reconstructions were performed at the University Hospital Regensburg, Germany, from July 2013 to January 2021. Standard high-resolution ultrasound (US) devices with linear multifrequency transducers of 4 to 18 MHz were used. Modes and device settings were evaluated regarding applicability by microsurgeons. Key steps for safe perforator identification and further optional steps for additional assessment should be discriminated. Results  Different US modes including brightness mode (B-mode), color flow (CF), power Doppler (PD), pulse wave (PW), and blood flow (B-Flow) were used. Transducers from 15 MHz and up were favorable to detect microvessels. Knobology of a standard US device regarding buttons, switches, and specific onscreen options with relevance for perforator mapping was subcategorized in four different groups. For qualitative and quantitative evaluation of microvessels, different US modes were tested with respect to their usefulness. Vital elements of the CCDS exam are disaggregated into three key steps for safe perforator identification and three optional steps for further perforator characterization. A standardized protocol for the CCDS exams was applied. Downregulation of pulse-repetition frequency/scale to adapt device sensitivity to slow-flow velocities represented the most important criterion to visualize microvessels. Qualitative microvessel evaluation was performed in B-mode, CCDS, PD mode, and B-Flow mode. Quantitative assessment was executed using PW-mode and CCDS measuring the microvessels' diameter (mm) and flow characteristics. Quantitative information may be obtained using PW-mode and the distance-measuring tool in CF-mode. Conclusion  Technical aspects with respect to proper device trimming and application decisively impact CCDS-guided perforator vessel identification and evaluation. [ABSTRACT FROM AUTHOR]

AIM: To evaluate the effectiveness of complementary imaging of high-resolution ultrasound including CEUS with PET/CT for tissue characterization and tumor detection. MATERIAL AND METHODS: 100 patients were examined with PET/CT and US/CEUS between January 2018 until February 2020. All patients underwent PET/CT followed by selective US/CEUS within 4 weeks. Comparison regarding concordant or diverging findings in PET/CT and US. Analysis of the differences concerning the lesions number of found by PET/CT and US/CEUS or the possibility of a secured diagnosis following ultrasound causing therapeutic changes. RESULTS: Diverging findings regarding the number of liver lesions in PET/CT and CEUS were found in 35 out of 64 patients (54%). Regarding renal lesions, a more definite diagnosis following ultrasound, causing a change of therapeutic approach, was achieved in 89%. Concordant results in PET/CT and US were found in 83% of patients with splenic and nodal findings. In 78% of patients with increased musculoskeletal or soft tissue tracer uptake, US was able to make a secured diagnosis with therapeutic changes. CONCLUSION: The present results indicate a strong benefit of complementary imaging of PET/CT and selective, high-resolution ultrasound especially in patients with liver, renal and musculoskeletal or soft tissue findings. [ABSTRACT FROM AUTHOR]

Early detection of pathologic variations in an arteriovenous fistula (AVF) is essential for preventing fistula dysfunction in individuals undergoing hemodialysis. This study aimed to evaluate the clinical applicability of 3-D tomographic ultrasound (tUS) for rapid and simple visualization of AVF morphology and pathology. We assessed 53 AVFs in 50 consecutive patients using 3-D tUS including secondary, blinded reading. For all examinations, a high-end ultrasound (US) device was used with linear probe, attached to a tUS system to allow freehand 3-D scanning. Participants were examined by 2-D US and 3-D tUS with different raw data (B-mode, power Doppler, B-flow). Additional angiography was available for 15 participants with scheduled interventions. In all participants, 3-D tUS allowed a 3-D representation of AVFs in angiographic-like images with good image quality. The 2-D US assessment took 7.9 ± 4.0 min. A 3-D power Doppler scan required, on average, 1.4 ± 0.6 min. Diagnostic accuracy of blinded reading for pathologies was high (86.8% for aneurysms and 79.2% for stenoses). Bland-Altman plots showed an excellent correlation of 3-D tUS with 2-D US and angiography. 3-D tUS is an easily and rapidly applicable method for visualizing morphologic and pathologic AVF variations. Color-coded 3-D reconstruction of power Doppler data simplifies detection of perfused aneurysms and stenoses. [ABSTRACT FROM AUTHOR]

Background  Preoperative ultrasound (US)-guided perforator mapping has immensely simplified perforator flap planning. It may be executed by the microsurgeon. Device settings and selection of ultrasound modes are of utmost significance for detection of low-flow microvessels. The following study evaluates different US modes. Methods  A prospective complete data acquisition was performed from July 2018 to June 2019 in a subset of patients who underwent US-guided flap planning. Multifrequency linear transducers were used applying five US modes. Brightness (B)-mode, color flow (CF), power Doppler (PD), pulse wave (PW), and B-flow modes were evaluated regarding applicability by microsurgeons. Peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were chosen to evaluate flow characteristics. US results were correlated to intraoperative findings. Results  A total number of eight patients (six males and two females) undergoing anterolateral thigh (ALT) or superficial circumflex iliac artery perforator (SCIP) flap surgery received an extensive standardized US-guided perforator characterization. Qualitative evaluation was performed in B-mode, color-coded duplex sonography (CCDS), PD, and B-flow mode. Quantitative assessment was executed using PW-mode and CCDS measuring the microvessels' diameter (mm) and flow characteristics (PSV, EDV, and RI). CCDS provided a mean diameter of 1.93 mm (range: 1.2–2.8 ± 0.51), a mean systolic peak of 16.9 cm/s (range: 9.9–33.4 ± 7.79), and mean RI of 0.71 (range: 0.55–0.87 ± 0.09) for lower limb perforators. All perforators located with US were verified by intraoperative findings. An optimized, time-effective US mapping algorithm was derived. Qualitative parameters may be evaluated with B-mode, CF, or B-flow. Smallest microvessels may be assessed in PD-mode. Lowering pulse-repetition frequency (PRF)/scale is mandatory to image low-flow microvessels as perforators. Quantitative information may be obtained using PW-mode and the distance-measuring tool in CF-mode. Image and video materials are provided. Conclusion  CCDS proved to be a powerful tool for preoperative perforator characterization when using a structured approach and mapping algorithm. Different techniques may be applied for specific visualizations and performed by the microsurgeon. [ABSTRACT FROM AUTHOR]

BACKGROUND: Besides mammography, breast ultrasound is the most important imaging modality for women with suspected breast cancer. New software tools bear high potential for improved detectability and specification of malignant breast lesions. OBJECTIVE: To compare the halo depicted around malignant breast lesions by ultrasound using Acoustic Structure Quantification (ASQ) of raw image data with the echogenic rim seen in B-mode ultrasound. METHODS: This retrospective study included 37 women for whom conventional B-mode ultrasound of the breast and ASQ were available as well as histopathology findings for comparison. Software tools were used to measure the halo area or echogenic rim and tumor area and calculate halo-to-lesion ratios for the two ultrasound modes. Six inexperienced readers characterized the breast lesions based on this information. Specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV) were determined. ANOVA, the Wilcoxon test, and ROC curve analysis were performed. RESULTS: There was a linear relationship between ASQ-based and B-mode-based halo-to-lesion ratios; however, a systematic error was also noted. ASQ-derived ratios tended to be higher for breast lesions with lymphangioinvasion (p = 0.051, n.s.) and higher N-stages (p > 0.925, n.s.), while there was no correlation with other markers. Because of the significantly greater conspicuity of peritumoral halos in the ASQ mode, inexperienced readers achieved greater sensitivity (78% vs. 74%) and specificity (75% vs. 71%) and higher NPVs (75% vs. 71%) and PPVs (78% vs. 74%) compared with B-mode images. Greater halo conspicuity affected the identification of malignant lesions with both modes; ASQ was found to be particularly well suited (FBimage (1,100) = 19.253, p < 0.001; FASQ (1,100) = 52.338, p < 0.001). The inexperienced readers were significantly more confident about their diagnosis using the ASQ maps (z = –3.023, p = 0.003). CONCLUSIONS: We conclude that the halo in ASQ and the echogenic rim in B-mode ultrasound are attributable to different morphologic correlates. ASQ improves diagnostic accuracy and confidence of inexperienced examiners because of improved halo visibility. [ABSTRACT FROM AUTHOR]

Complications rates after free flap transplantation still amount up to 5%. Consequently a reliable monitoring system is of high importance in plastic and reconstructive surgery. The following guidelines provide an overviewof the current opportunities for free flap planning and monitoring with ultrasound and in particular with contrast enhanced ultrasound. [ABSTRACT FROM AUTHOR]

Background/Aims: Some suggest MRI to be superior to ultrasound in Crohn's disease. We analyzed how often MR enterography (MRE) following a routine ultrasound leads to a change in therapeutic decision. Material and Methods: We retrospectively evaluated 47 patients with Crohn's disease undergoing routine ultrasound examination. Actual medical history, complete blood count, C-reactive protein (CRP), and sonographic findings were assessed independently by two specialists who retrospectively provided a therapeutic proposal. Additionally, all patients received MRE. Thereafter, the specialists had to provide a new therapeutic concept regarding all the available information. Results: Evaluation of the rectum was not successful by ultrasound, but MRE gave good results. Only 1 of 7 abscesses was identified sonographically. Three of the abscesses missed at sonography were localized in the perirectal/perianal region. MRE detected more inflamed bowel segments, but ultrasound assessment of anatomically fixed bowel parts showed good recognition by MRE. With increasing CRP values, we found more positive results of ultrasound and MRE. Therapeutic change was suggested in only 18 patients. Conclusions: Ultrasound should be performed by an experienced examiner, and a proctological examination should be added. MRE is justified in cases of discrepancy between clinical findings and the results of diagnostic ultrasound and, moreover, if Crohn's lesions are suspected at sites proximal to the terminal or neoterminal ileum. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]