Open Access
Open access
Digital Diagnostics, volume 2, issue 3, pages 261-276

Doppler twinkling artifact observations: an open-access database of raw ultrasonic signals

Denis Leonov 1
, 
Roman Reshetnikov 2
, 
Nicholas Kulberg 3
, 
Anastasia Nasibullina 4
, 
A. I. Gromov 5
1
 
2
 
3
 
4
 
5
 
Publication type: Journal Article
Publication date: 2021-10-15
scimago Q3
SJR: 0.207
CiteScore: 1.3
Impact factor: —
ISSN: 27128490, 27128962
Abstract

BACKGROUND: Doppler twinkling artifact is a rapid change of colors seen in CFI-mode in the presence of kidney stones and calculi. Therefore, numerous researchers use the twinkling artifact as a diagnostic sign. However, this phenomenon is under-researched, because most assumptions concerning its causes are made based on pure visual observations of the scanners screen leaving the important steps of signal transformation hidden behind the black box curtains of ultrasound machines. MATERIALS AND METHODS: Raw radiofrequency ultrasound signals were recorded in the phantom studies. The recorded echoes were received from objects that create the Doppler twinkling artifact and artificial blood vessels and soft tissues imitators. The data were collected between June 2016 and March 2021. Sonomed-500 with the 7.5 L38 and 3.4 C60 probes served as the research machine for the signal capture. Data records: We present the database containing raw radiofrequency ultrasound signals from the beam former output of the research ultrasound machine. The dataset consists of CFI and B-mode echoes recorded from twinkling objects. Therefore, this database can be useful for those who test, develop and study ultrasound signal processing algorithms. Furthermore, the database is freely available online. The 10.5 GB database consists of echoes received from five phantoms. Raw radiofrequency signals were stored in the binary files; scanning parameters were stored in text files. The database is available at: https://mosmed.ai/datasets/ultrasound_doppler_twinkling_artifact. Code availability: The public can visualize the database content with the specially written program TwinklingDatasetDisplay available at: https://github.com/Center-of-Diagnostics-and-Telemedicine/TwinklingDatasetDisplay.git. Usage notes: The database can be used to test and develop signal-processing algorithms, such as wall filtration, velocity estimation, feature extraction, speckle reduction, etc. Furthermore, the public is free to share (copy, distribute, and transmit) and remix (adapt and do derivative works) the dataset considering appropriate credit is given.

Found 34
By date By citations
Springer Nature
Detection of Microcalcifications using the Ultrasound Doppler Twinkling Artifact
Leonov D.V., Kulberg N.S., Gromov A.I., Morozov S.P.
Bio-Medical Engineering scimago Q4 , 
2020-09-10,  citations by CoLab: 9 ,  Abstract  
We analyzed the possibility to detect microcalcifications using a novel ultrasound diagnostic mode based on advanced analysis of the color Doppler twinkling artifact. The special mode was tested with two phantoms: a commercially available polyurethane mammographic breast phantom with dense inclusions simulating microcalcifications and a phantom developed in our laboratory and containing chemically grown CaSO4 microcrystals less than 200 μm in size. The mineral inclusions in the first phantom were visible in B-mode and correctly detected with the novel mode. The presence of inclusions in the second phantom was not obvious when imaged in B-mode; however, it was reliably detected with the special mode. The special mode used two colors to distinguish between the physical processes behind the color Doppler twinkling artifact — elastic vibration and microcavitation. This research demonstrated the applicability and usefulness of the special diagnostic mode for the detection of microcalcifications in phantoms.
Springer Nature
Clutter Filtering for Diagnostic Ultrasound Color Flow Imaging
Leonov D.V., Kulberg N.S., Fin V.A., Podmoskovnaya V.A., Ivanova L.S., Shipaeva A.S., Vladzimirskiy A.V., Morozov S.P.
Bio-Medical Engineering scimago Q4 , 
2019-09-12,  citations by CoLab: 6 ,  Abstract  
Clutter filtering plays an important role in constructing a quality color flow map in ultrasound Doppler imaging. Signals from slow-moving tissues and vessel walls are clutter as they often mix with reflections from blood and should be suppressed for the further correct estimation of flow parameters. Their complete suppression in color flow imaging is difficult, because these signals on average are 40-60 dB more powerful than the signals from blood, the length of the Doppler sequence is very short, and there is always a demand for a real-time operation. This article provides a general model of the Doppler signal and discusses filters based on polynomial and adaptive regression, empirical mode decomposition, and prospective combined approaches to blood flow filtering.
Springer Nature
Comparison of Filtering Techniques in Ultrasound Color Flow Imaging
Leonov D.V., Kulberg N.S., Fin V.A., Podmoskovnaya V.A., Ivanova L.S., Shipaeva A.S., Vladzimirskiy A.V., Morozov S.P.
Bio-Medical Engineering scimago Q4 , 
2019-07-15,  citations by CoLab: 5 ,  Abstract  
The article considers filtering techniques used to suppress clutter signals from moving tissues and to improve reliability of blood flow estimation. It compares polynomial and adaptive bases such as the result of empirical mode decomposition and singular vectors obtained through Karhunen−Loève transform. Filtering techniques are examined using a computer-simulated model, Doppler flow phantom and in vivo data. Filters are compared in terms of computational complexity, ability to retrieve flow profile without errors and through ROC curve analysis. Polynomial regression filters with tissue phase shift compensation were found to be the best fit for clutter suppression in terms of computational demands and accuracy of velocity estimation.
Elsevier
Utilidad del artefacto Doppler de centelleo de color (twinkle) en la detección ecográfica de microcalcificaciones mamarias
Relea A., Alonso J.A., González M., Zornoza C., Bahamonde S., Viñuela B.E., Encinas M.B.
Radiologia scimago Q3 wos Q3 , 
2018-09-01,  citations by CoLab: 7 ,  Abstract  
Resumen Objetivo Verificar si el artefacto de twinkle (AT) se corresponde con la presencia de microcalcificaciones previamente vistas mediante mamografia, y valorar su utilidad en el manejo ecografico de microcalcificaciones sospechosas. Material y metodos Hemos examinado prospectivamente mediante ecografia a 46 pacientes consecutivas con grupos de microcalcificaciones sospechosos de malignidad, sin otros hallazgos mamograficos de sospecha, buscando la presencia del AT para identificar las microcalcificaciones. Cuando lo conseguimos, procedimos a biopsiarlas con aguja gruesa (BAG) 11G, y posteriormente comprobamos la presencia de las microcalcificaciones mediante radiografia de las muestras obtenidas. Analizamos el porcentaje de deteccion y obtencion de microcalcificaciones con la BAG, usando esta tecnica, asi como la concordancia radiopatologica. Las microcalcificaciones no detectadas con ecografia, o no concordantes, fueron biopsiadas mediante estereotaxia en otro centro. Tambien utilizamos guia ecografica para el marcaje preoperatorio con arpones, orientandolos habitualmente de forma radial. Resultados Se identificaron y biopsiaron con ecografia 41 de las 46 lesiones, incluyendo 24 de los 25 carcinomas (17 de ellos in situ). La ecografia en modo B basto para biopsiar las microcalcificaciones en 14 pacientes, aunque en 6 de ellas el AT incremento el numero de microcalcificaciones detectadas, lo que permitio un marcaje preoperatorio mas preciso. Gracias al AT identificamos 27 grupos adicionales (89% vs. 30%; p  Conclusiones El AT es una herramienta util para la identificacion ecografica de microcalcificaciones, lo que permite un significativo incremento de las biopsias guiadas por ecografia, asi como una mejor delimitacion preoperatoria.
Pleiades Publishing
Diagnostic Mode Detecting Solid Mineral Inclusions in Medical Ultrasound Imaging
Leonov D.V., Kulberg N.S., Gromov A.I., Morozov S.P., Vladzimirskiy A.V.
Acoustical Physics scimago Q3 wos Q4 , 
2018-09-01,  citations by CoLab: 7 ,  Abstract  
The proposed ultrasound imaging mode allows detection of objects, which essentially differ in their scattering properties from the surrounding tissues and liquids. The objects in question are primarily microcalcifications, renal and urinary stones. Our previous study has shown that the Doppler signals from these objects have two components common for echoes from solid mineral inclusions. They can be in superposition with the blood and noise signals. One of these two mineral-related components is characterized by cavitation, the other – by elastic vibrations of the object presumably caused by acoustic radiation force. According to statistical and energy parameters, these components differ from each other, as well as from noise and blood echoes. The article proposes a practical method for identifying signals with mineral-related components. This method is the base for the novel diagnostic visualization mode specifically designed for the mineral inclusions detection with ultrasound.
Elsevier
Color Doppler Twinkling Artifact in Diagnosis of Tuberculous Pleuritis: A Comparison with Gray-Scale Ultrasonography and Computed Tomography
Tian J., Xu L.
Ultrasound in Medicine and Biology scimago Q1 wos Q2 , 
2018-06-01,  citations by CoLab: 2 ,  Abstract  
The aim of this study was to determine whether twinkling artifact (TA) detected on color Doppler ultrasonography can effectively determine the presence of pleural calcification compared with computed tomography (CT) and differentiate tuberculous pleuritis (TP) and cancerous pleuritis (CP). One hundred six cases of TP and 26 cases of CP were scanned using gray-scale ultrasonography (GSU) and TA to determine the presence of pleural calcification. With CT as the reference standard, 63.3% and 79.6% of patients with pleural calcification were identified with GSU and TA, respectively. The detection rate of TA was higher than that of GSU (p = 0.039). For the whole study population, 37.1% were identified as having pleural calcification with CT, significantly higher than the proportion detected with GSU (25.8%, p = 0.001), but not different from that detected with TA (41.7%, p = 0.327). The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of TA were 79.6%, 80.7%, 80.3%, 70.9% and 87.0%, respectively. The detection rate of TA was significantly higher than that of GSU (p
Institute of Electrical and Electronics Engineers (IEEE)
Receiver-Operating Characteristic Analysis of Eigen-Based Clutter Filters for Ultrasound Color Flow Imaging
Chee A.J., Yu A.C.
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control scimago Q1 wos Q2 , 
2018-03-01,  citations by CoLab: 12 ,  Abstract  
The eigen-based filter has theoretically established itself as a potent solution in ultrasound color flow imaging (CFI) for combating against clutter arising from moving tissues. Yet, it remains poorly understood on how much gain in flow detection sensitivity and specificity can be delivered by this adaptive clutter filter. Here, we investigated the receiver operating characteristic (ROC) of the eigen-based clutter filter to statistically evaluate its efficacy. Our investigation was conducted using a new vascular phantom testbed that incorporated both intrinsic tissue motion (vessel pulsation: 7.58 cm/s peak velocity) and extrinsic tissue motion (vibration: 5-Hz frequency, 2.98 cm/s peak velocity), as well as pulsatile flow (pulse rate: 60 beats/min; systolic flow rate: 6.5 mL/s). The eigen-filter (single-ensemble formulation) was applied to CFI raw data sets obtained from the phantom's short-axis view (slow-time ensemble size: 12; pulse repetition frequency: 2 kHz; and ultrasound frequency: 5 MHz), and post-filter Doppler power was compared between flow and tissue regions. Results show that, in the presence of vessel pulsation and tissue vibration, the eigen-filter yielded a high true positive rate in depicting flow pixels in CFI frames (0.945 and 0.917, respectively, during peak systole and end diastole at 60° beam-flow angle), while maintaining a low false alarm rate (0.10) in rendering tissue pixels. Also, the eigen-filter posed ROC curves whose area under curve was higher than those for the polynomial regression filter (statistically significant; t-test p values were less than 0.05). These findings serve well to substantiate the merit of using eigen-filters to enhance the vascular visualization capability of CFI.
IOP Publishing
The role of trapped bubbles in kidney stone detection with the color Doppler ultrasound twinkling artifact
Simon J.C., Sapozhnikov O.A., Kreider W., Breshock M., Williams J.C., Bailey M.R.
Physics in Medicine and Biology scimago Q1 wos Q1 , 
2018-01-09,  citations by CoLab: 27 ,  Abstract  
The color Doppler ultrasound twinkling artifact, which highlights kidney stones with rapidly changing color, has the potential to improve stone detection; however, its inconsistent appearance has limited its clinical utility. Recently, it was proposed stable crevice bubbles on the kidney stone surface cause twinkling; however, the hypothesis is not fully accepted because the bubbles have not been directly observed. In this paper, the micron or submicron-sized bubbles predicted by the crevice bubble hypothesis are enlarged in kidney stones of five primary compositions by exposure to acoustic rarefaction pulses or hypobaric static pressures in order to simultaneously capture their appearance by high-speed photography and ultrasound imaging. On filming stones that twinkle, consecutive rarefaction pulses from a lithotripter caused some bubbles to reproducibly grow from specific locations on the stone surface, suggesting the presence of pre-existing crevice bubbles. Hyperbaric and hypobaric static pressures were found to modify the twinkling artifact; however, the simple expectation that hyperbaric exposures reduce and hypobaric pressures increase twinkling by shrinking and enlarging bubbles, respectively, largely held for rough-surfaced stones but was inadequate for smoother stones. Twinkling was found to increase or decrease in response to elevated static pressure on smooth stones, perhaps because of the compression of internal voids. These results support the crevice bubble hypothesis of twinkling and suggest the kidney stone crevices that give rise to the twinkling phenomenon may be internal as well as external.
Pleiades Publishing
Causes of Ultrasound Doppler Twinkling Artifact
Leonov D.V., Kulberg N.S., Gromov A.I., Morozov S.P., Kim S.Y.
Acoustical Physics scimago Q3 wos Q4 , 
2018-01-01,  citations by CoLab: 13 ,  Abstract  
Ultrasound Doppler twinkling artifact is analyzed. It usually appears as a frequent color alteration in the region of hyperechoic objects. Its noiselike spectrum can also be seen in spectral Doppler mode. Physicians use twinkling artifact as a clinical sign for kidney-stone and soft-tissue calculi detection. The advantageous peculiarity of this study is that the experiments were conducted utilizing raw signals obtained from a custom ultrasonic machine and a specially developed phantom. The phantom contained specimens with known qualities, allowing for reproducible and predictable results. The experiments revealed evidence for two physical causes of twinkling artifact, which were associated with two unique Doppler signals. The research laid the foundation for the new reflected-signal model introduced and used throughout this paper.
Elsevier
Twinkling Artifact of Microcalcifications in Breast Ultrasound
Fujimoto Y., Shimono C., Shimoyama N., Osaki M.
Ultrasound in Medicine and Biology scimago Q1 wos Q2 , 
2017-09-30,  citations by CoLab: 2 , 
Institute of Electrical and Electronics Engineers (IEEE)
A GPU-Parallelized Eigen-Based Clutter Filter Framework for Ultrasound Color Flow Imaging
Chee A.J., Yiu B.Y., Yu A.C.
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control scimago Q1 wos Q2 , 
2017-01-01,  citations by CoLab: 21 ,  Abstract  
Eigen-filters with attenuation response adapted to clutter statistics in color flow imaging (CFI) have shown improved flow detection sensitivity in the presence of tissue motion. Nevertheless, its practical adoption in clinical use is not straightforward due to the high computational cost for solving eigendecompositions. Here, we provide a pedagogical description of how a real-time computing framework for eigen-based clutter filtering can be developed through a single-instruction, multiple data (SIMD) computing approach that can be implemented on a graphical processing unit (GPU). Emphasis is placed on the single-ensemble-based eigen-filtering approach (Hankel singular value decomposition), since it is algorithmically compatible with GPU-based SIMD computing. The key algebraic principles and the corresponding SIMD algorithm are explained, and annotations on how such algorithm can be rationally implemented on the GPU are presented. Real-time efficacy of our framework was experimentally investigated on a single GPU device (GTX Titan X), and the computing throughput for varying scan depths and slow-time ensemble lengths was studied. Using our eigen-processing framework, real-time video-range throughput (24 frames/s) can be attained for CFI frames with full view in azimuth direction (128 scanlines), up to a scan depth of 5 cm ($\lambda $ pixel axial spacing) for slow-time ensemble length of 16 samples. The corresponding CFI image frames, with respect to the ones derived from non-adaptive polynomial regression clutter filtering, yielded enhanced flow detection sensitivity in vivo, as demonstrated in a carotid imaging case example. These findings indicate that the GPU-enabled eigen-based clutter filtering can improve CFI flow detection performance in real time.
Institute of Electrical and Electronics Engineers (IEEE)
Ultrasound Small Vessel Imaging With Block-Wise Adaptive Local Clutter Filtering
Song P., Manduca A., Trzasko J.D., Chen S.
IEEE Transactions on Medical Imaging scimago Q1 wos Q1 , 
2017-01-01,  citations by CoLab: 188 ,  Abstract  
Robust clutter filtering is essential for ultrasound small vessel imaging. Eigen-based clutter filtering techniques have recently shown great improvement in clutter rejection over conventional clutter filters in small animals. However, for in vivo human imaging, eigen-based clutter filtering can be challenging due to the complex spatially-varying tissue and noise characteristics. To address this challenge, we present a novel block-wise adaptive singular value decomposition (SVD) based clutter filtering technique. The proposed method divides the global plane wave data into overlapped local spatial segments, within which tissue signals are assumed to be locally coherent and noise locally stationary. This, in turn, enables effective separation of tissue, blood and noise via SVD. For each block, the proposed method adaptively determines the singular value cutoff thresholds based on local data statistics. Processing results from each block are redundantly combined to improve both the signal-to-noise-ratio (SNR) and the contrast-to-noise-ratio (CNR) of the small vessel perfusion image. Experimental results show that the proposed method achieved more than two-fold increase in SNR and more than three-fold increase in CNR in dB scale over the conventional global SVD filtering technique for an in vivo human native kidney study. The proposed method also showed substantial improvement in suppression of the depth-dependent background noise and better rejection of near field tissue clutter. The effects of different processing block size and block overlap percentage were systematically investigated as well as the tradeoff between imaging quality and computational cost.
Institute of Electrical and Electronics Engineers (IEEE)
Visualization of Small-Diameter Vessels by Reduction of Incoherent Reverberation With Coherent Flow Power Doppler
Li Y.L., Hyun D., Abou-Elkacem L., Willmann J.K., Dahl J.J.
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control scimago Q1 wos Q2 , 
2016-11-01,  citations by CoLab: 47 ,  Abstract  
Power Doppler (PD) imaging is a widely used technique for flow detection. Despite the wide use of Doppler ultrasound, limitations exist in the ability of Doppler ultrasound to assess slow flow in the small-diameter vasculature, such as the maternal spiral arteries and fetal villous arteries of the placenta and focal liver lesions. The sensitivity of PD in small vessel detection is limited by the low signal produced by slow flow and the noise associated with small vessels. The noise sources include electronic noise, stationary or slowly moving tissue clutter, reverberation clutter, and off-axis scattering from tissue, among others. In order to provide more sensitive detection of slow flow in small diameter vessels, a coherent flow imaging technique, termed coherent flow PD (CFPD), is characterized and evaluated with simulation, flow phantom experiment studies, and an in vivo animal small vessel detection study. CFPD imaging was introduced as a technique to detect slow blood flow. It has been demonstrated to detect slow flow below the detection threshold of conventional PD imaging using identical pulse sequences and filter parameters. In this paper, we compare CFPD with PD in the detection of blood flow in small-diameter vessels. The results from the study suggest that CFPD is able to provide a 7.5-12.5-dB increase in the signal-to-noise ratio (SNR) over PD images for the same physiological conditions and is less susceptible to reverberation clutter and thermal noise. Due to the increase in SNR, CFPD is able to detect small vessels in high channel noise cases, for which PD was unable to generate enough contrast to observe the vessel.
Springer Nature
Can Doppler ultrasonography twinkling artifact be used as an alternative imaging modality to non-contrast-enhanced computed tomography in patients with ureteral stones? A prospective clinical study
Sen V., Imamoglu C., Kucukturkmen I., Degirmenci T., Bozkurt I.H., Yonguc T., Aydogdu O., Gunlusoy B.
Urolithiasis scimago Q1 wos Q2 , 
2016-05-12,  citations by CoLab: 12 ,  Abstract  
We aimed to evaluate the use of twinkling artifact (TA) on color Doppler ultrasonography (USG) as an alternative imaging modality to non-contrast-enhanced computed tomography (CT) in patients with ureteral stones in this prospective study. Totally, 106 consecutive patients who had been diagnosed with ureterolithiasis by CT were enrolled in this prospective study. A urinary system color Doppler ultrasonography was performed on the same day with CT by an experienced radiologist who was blinded to the CT scan. TA was graded as 0, 1 and 2. The overall specificity of TA was calculated according to the NCCT as a gold standard method. The size, side and localization of stone and the demographic characteristics of patients were compared with twinkling positivity. TA on color Doppler USG was detected in 92 (86.8 %) patients. Statistically significant difference was found between the TA and localization of ureteral stones (p = 0.044). When we sub-grouped the patients according to the TA grades as 0, 1 and 2, 14 patients were with TA grade 0, 55 with TA grade 1 and 37 with TA grade 2. The mean stone size of groups was significantly different (p = 0.012). Bigger and proximal ureteral stones tended to have more TA on color Doppler USG. TA on color Doppler USG could be a good and safe alternative imaging modality with comparable results between NCCT. It could be useful for the diagnosis and follow-up of patients with ureterolithiasis.
American Roentgen Ray Society
Clinical Effectiveness of Prospectively Reported Sonographic Twinkling Artifact for the Diagnosis of Renal Calculus in Patients Without Known Urolithiasis.
Masch W.R., Cohan R.H., Ellis J.H., Dillman J.R., Rubin J.M., Davenport M.S.
American Journal of Roentgenology scimago Q1 wos Q1 , 
2016-01-21,  citations by CoLab: 42 ,  Abstract  
OBJECTIVE The purpose of this study was to determine the clinical effectiveness of prospectively reported sonographic twinkling artifact for the diagnosis of renal calculus in patients without known urolithiasis. MATERIALS AND METHODS All ultrasound reports finalized in one health system from June 15, 2011, to June 14, 2014, that contained the words "twinkle" or "twinkling" in reference to suspected renal calculus were identified. Patients with known urolithiasis or lack of a suitable reference standard (unenhanced abdominal CT with ≤ 2.5-mm slice thickness performed ≤ 30 days after ultrasound) were excluded. The sensitivity, specificity, and positive likelihood ratio of sonographic twinkling artifact for the diagnosis of renal calculus were calculated by renal unit and stratified by two additional diagnostic features for calcification (echogenic focus, posterior acoustic shadowing). RESULTS Eighty-five patients formed the study population. Isolated sonographic twinkling artifact had sensitivity of 0.78 (82/105), specificity of 0.40 (26/65), and a positive likelihood ratio of 1.30 for the diagnosis of renal calculus. Specificity and positive likelihood ratio improved and sensitivity declined when the following additional diagnostic features were present: sonographic twinkling artifact and echogenic focus (sensitivity, 0.61 [64/105]; specificity, 0.65 [42/65]; positive likelihood ratio, 1.72); sonographic twinkling artifact and posterior acoustic shadowing (sensitivity, 0.31 [33/105]; specificity, 0.95 [62/65]; positive likelihood ratio, 6.81); all three features (sensitivity, 0.31 [33/105]; specificity, 0.95 [62/65]; positive likelihood ratio, 6.81). CONCLUSION Isolated sonographic twinkling artifact has a high false-positive rate (60%) for the diagnosis of renal calculus in patients without known urolithiasis.
Found 1
By date By citations
Springer Nature
Efficiency of ultrasound color flow imaging in the presence of twinkling artifact
Leonov D.V.
Bio-Medical Engineering scimago Q4 , 
2024-03-25,  citations by CoLab: 0 ,  Abstract  
Traditional blood flow mapping algorithms are not effective enough when the region of interest contains the sources of artifacts. This paper examines the signatures of blood flow signals, as well as noise and artifact signals. Mathematical rules are proposed on the basis of these features to discriminate the blood flow signal from other signals, including the Doppler twinkling artifact. The diagnostic efficiency of the proposed decision rules is assessed using the previously collected database of raw ultrasound Doppler signals. The study results showed that taking account of the spatial stability of blood flow velocity can increase diagnostic efficiency to 91.6%.

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