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Ronald S Adler - One of the best experts on this subject based on the ideXlab platform.
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Pediatric hip effusions: evaluation with Power Doppler sonography.
Radiology, 1998Co-Authors: Peter J. Strouse, Michael A. Dipietro, Ronald S AdlerAbstract:PURPOSE: To determine if Power Doppler sonography allows differentiation of infectious from noninfectious hip effusions and thereby obviates joint aspiration. MATERIALS AND METHODS: Twenty-nine consecutive children (30 hips) with sonographically identified hip effusion were prospectively evaluated with Power Doppler sonography. Both hips were evaluated in each patient by using identical imaging parameters and were then compared. Medical charts were reviewed to determine the eventual diagnosis. RESULTS: At Power Doppler sonography, none of 16 patients with transient synovitis had increased flow in the affected hip compared with the contralateral normal hip. Of 11 patients with septic arthritis, one had asymmetric increased flow, and two others, in whom contralateral comparison images were limited, had probable increased flow. Three patients with miscellaneous diagnoses had symmetric normal flow. CONCLUSION: Because Power Doppler sonograms did not depict increased flow in most patients with septic arthritis...
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Power Doppler sonography of synovitis assessment of therapeutic response preliminary observations
Radiology, 1996Co-Authors: Joel S Newman, Timothy J Laing, Conor J Mccarthy, Ronald S AdlerAbstract:Power Doppler sonography was used in eight symptomatic knees in seven patients with arthritis before and after joint aspiration and intraarticular administration of steroids. A qualitative decrease in synovial perfusion was observed in all eight knees, and symptoms improved in seven of the eight cases. These preliminary data suggest a role for Power Doppler sonography in assessment of serial changes in synovial inflammation.
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AUTOCORRELATION OF INTEGRATED Power Doppler SIGNALS AND ITS APPLICATION
Ultrasound in medicine & biology, 1996Co-Authors: Jian-feng Chen, Jonathan M. Rubin, J. Brian Fowlkes, Paul L. Carson, Ronald S AdlerAbstract:The integrated Power Doppler signal arising from blood flow is a random process. In this article, a general approach to model this random process is studied. Both the theoretical and experimental results show that the temporal autocorrelation function of the integrated Power Doppler signals is directly related to properties of the insonified medium, such as the scattering strengths and velocities of all moving scatterers, and as well as the properties of the Doppler imaging system, such as the point spread function (psf) of the Power Doppler images. Some initial experiments are performed to test the proposed model. Its potential application for flow measurement, such as perfusion evaluation, is also discussed.
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Power Doppler sonography in the assessment of musculoskeletal fluid collections.
AJR. American journal of roentgenology, 1996Co-Authors: William H. Breidahl, Joel S Newman, Mihra S. Taljanovic, Ronald S AdlerAbstract:Power Doppler sonography is a relatively new technique that has been shown to depict hyperemia associated with musculoskeletal inflammatory disease. We performed this study to evaluate the ability of Power Doppler sonography to differentiate musculoskeletal fluid collections of varying etiologies.Gray-scale and Power Doppler sonography were performed on 39 patients with joint effusions or appendicular fluid collections. Blood flow (hyperemia) in the soft tissues adjacent to the fluid collections was subjectively analyzed and graded on a scale of 1 to 4 (1, normal flow; 2-4, increasing degrees of hyperemia). All fluid collections were aspirated within 24 hr of the sonographic examination. We found 31 joint effusions and 12 periarticular collections with appropriate imaging and pathologic correlation.Adjacent to 36 effusions and fluid collections, we saw moderate or marked hyperemia. Thirty-five of the 36 had an inflammatory or neoplastic cause, including 15 infected collections. One fluid collection had a ...
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fractional moving blood volume estimation with Power Doppler us
Radiology, 1995Co-Authors: Jonathan M. Rubin, Ronald S Adler, Jian-feng Chen, J B Fowlkes, S Spratt, J E Pallister, Paul L. CarsonAbstract:PURPOSE: To estimate the fraction of moving blood in tissue with Power Doppler ultrasound (US). MATERIALS AND METHODS: Power Doppler US measurements of moving scatterers in a flow tube were made as a function of successive dilutions of the perfusate. Measurements were normalized relative to the maximum Doppler Power in the center of the flow tube at the highest concentration and were used to calculate the fractional dilution of the perfusate for each run with each dilution used to represent increasing amounts of non-moving soft tissue in the sample volume. The technique was also applied to two clinical examples. RESULTS: Successive dilutions of the perfusate in the flow experiment showed a monotonic, linear decrease in the Doppler Power as a function of dilution. CONCLUSION: The Power Doppler US technique has the potential to more accurately estimate alterations in blood flow and has the advantage of being a continuous parameter that can be depth normalized.
Jonathan M. Rubin - One of the best experts on this subject based on the ideXlab platform.
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Power Doppler: It's a good thing
Seminars in ultrasound CT and MR, 1997Co-Authors: Kieran J. Murphy, Jonathan M. RubinAbstract:Power Doppler is a new method of ultrasound flow imaging the utility of which is currently under investigation. This technique creates a flow map based on the integrated Power of the Doppler spectrum, rather than mean Doppler frequency. Power Doppler imaging is inherently more sensitive in terms of flow detection than standard color Doppler imaging; therefore, Power Doppler can display flow for situations in which color Doppler is ineffective and can even display tissue perfusion in highly vascular organs such as the kidneys. Furthermore, Power Doppler is not effected by aliasing, nor is it effected by blooming in the same way as color Doppler, which has deleterious effects on color Doppler flow images. The control of blooming with Power Doppler may be of great importance in the clinical application of echo-enhancing agents. This review article discusses in detail the technological advantages and disadvantages of Power Doppler flow imaging. In addition, it provides a synopsis of the preliminary research studies that have been conducted to date with respect to the clinical applications of Power Doppler.
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AUTOCORRELATION OF INTEGRATED Power Doppler SIGNALS AND ITS APPLICATION
Ultrasound in medicine & biology, 1996Co-Authors: Jian-feng Chen, Jonathan M. Rubin, J. Brian Fowlkes, Paul L. Carson, Ronald S AdlerAbstract:The integrated Power Doppler signal arising from blood flow is a random process. In this article, a general approach to model this random process is studied. Both the theoretical and experimental results show that the temporal autocorrelation function of the integrated Power Doppler signals is directly related to properties of the insonified medium, such as the scattering strengths and velocities of all moving scatterers, and as well as the properties of the Doppler imaging system, such as the point spread function (psf) of the Power Doppler images. Some initial experiments are performed to test the proposed model. Its potential application for flow measurement, such as perfusion evaluation, is also discussed.
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fractional moving blood volume estimation with Power Doppler us
Radiology, 1995Co-Authors: Jonathan M. Rubin, Ronald S Adler, Jian-feng Chen, J B Fowlkes, S Spratt, J E Pallister, Paul L. CarsonAbstract:PURPOSE: To estimate the fraction of moving blood in tissue with Power Doppler ultrasound (US). MATERIALS AND METHODS: Power Doppler US measurements of moving scatterers in a flow tube were made as a function of successive dilutions of the perfusate. Measurements were normalized relative to the maximum Doppler Power in the center of the flow tube at the highest concentration and were used to calculate the fractional dilution of the perfusate for each run with each dilution used to represent increasing amounts of non-moving soft tissue in the sample volume. The technique was also applied to two clinical examples. RESULTS: Successive dilutions of the perfusate in the flow experiment showed a monotonic, linear decrease in the Doppler Power as a function of dilution. CONCLUSION: The Power Doppler US technique has the potential to more accurately estimate alterations in blood flow and has the advantage of being a continuous parameter that can be depth normalized.
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Detection of Soft-Tissue Hyperemia: Valueof Power Doppler
1994Co-Authors: Joel S Newman, Jonathan M. RubinAbstract:OBJECTIVE. Power Doppler sonography is a new technique that offers extended dynamic range over that provided by conventional color Doppler imaging, thereby facilitating measurement of tissue perfusion. We evaluated the efficacy of Power Doppier sonography in depicting soft-tissue hyperemia in musculoskeletal inflammatory conditions. SUBJECTS AND METHODS. Twenty-three patients with predominantly unifocal musculoskeletal symptoms were evaluated with conventional gray-scale imaging and Power Doppler sonography. The shoulder was evaluated in 14 patients, the elbow in three, and various other sites in six. For comparison purposes, the contralateral asymptomatic joint or site was examined in 17 cases. Fluid collections were aspirated in seven patients. RESULTS. Soft-tissue hyperemia was seen on Power Doppler sonograms at the symptomatic site(s) in 22 of 23 cases studied, with an appearance ranging from frank tissue blush to large, isolated peritendinous/peribursal vessels. Findings associated with hyperemia Included rotator cuff tendinitis and/or tear, bursitis, and symptomatic wrist ganglia. Findings on Power Doppler sonograms were normal in one patient who had a small, sterile hip joint effusion, and findings on subsequent scintigrams, pelvic radiographs, and CT scans were normal. CONCLUSION. Power Doppler sonography consistently shows hyperperfusion associated with musculoskeletal inflammatory disease. As such, it represents a use
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detection of soft tissue hyperemia value of Power Doppler sonography
American Journal of Roentgenology, 1994Co-Authors: Joel S Newman, Ronald S Adler, Ronald O Bude, Jonathan M. RubinAbstract:Power Doppler sonography is a new technique that offers extended dynamic range over that provided by conventional color Doppler imaging, thereby facilitating measurement of tissue perfusion. We evaluated the efficacy of Power Doppler sonography in depicting soft-tissue hyperemia in musculoskeletal inflammatory conditions.Twenty-three patients with predominantly unifocal musculoskeletal symptoms were evaluated with conventional gray-scale imaging and Power Doppler sonography. The shoulder was evaluated in 14 patients, the elbow in three, and various other sites in six. For comparison purposes, the contralateral asymptomatic joint or site was examined in 17 cases. Fluid collections were aspirated in seven patients.Soft-tissue hyperemia was seen on Power Doppler sonograms at the symptomatic site(s) in 22 of 23 cases studied, with an appearance ranging from frank tissue blush to large, isolated peritendinous/peribursal vessels. Findings associated with hyperemia included rotator cuff tendinitis and/or tear, b...
Joel S Newman - One of the best experts on this subject based on the ideXlab platform.
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Power Doppler sonography of synovitis assessment of therapeutic response preliminary observations
Radiology, 1996Co-Authors: Joel S Newman, Timothy J Laing, Conor J Mccarthy, Ronald S AdlerAbstract:Power Doppler sonography was used in eight symptomatic knees in seven patients with arthritis before and after joint aspiration and intraarticular administration of steroids. A qualitative decrease in synovial perfusion was observed in all eight knees, and symptoms improved in seven of the eight cases. These preliminary data suggest a role for Power Doppler sonography in assessment of serial changes in synovial inflammation.
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Power Doppler sonography in the assessment of musculoskeletal fluid collections.
AJR. American journal of roentgenology, 1996Co-Authors: William H. Breidahl, Joel S Newman, Mihra S. Taljanovic, Ronald S AdlerAbstract:Power Doppler sonography is a relatively new technique that has been shown to depict hyperemia associated with musculoskeletal inflammatory disease. We performed this study to evaluate the ability of Power Doppler sonography to differentiate musculoskeletal fluid collections of varying etiologies.Gray-scale and Power Doppler sonography were performed on 39 patients with joint effusions or appendicular fluid collections. Blood flow (hyperemia) in the soft tissues adjacent to the fluid collections was subjectively analyzed and graded on a scale of 1 to 4 (1, normal flow; 2-4, increasing degrees of hyperemia). All fluid collections were aspirated within 24 hr of the sonographic examination. We found 31 joint effusions and 12 periarticular collections with appropriate imaging and pathologic correlation.Adjacent to 36 effusions and fluid collections, we saw moderate or marked hyperemia. Thirty-five of the 36 had an inflammatory or neoplastic cause, including 15 infected collections. One fluid collection had a ...
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Detection of Soft-Tissue Hyperemia: Valueof Power Doppler
1994Co-Authors: Joel S Newman, Jonathan M. RubinAbstract:OBJECTIVE. Power Doppler sonography is a new technique that offers extended dynamic range over that provided by conventional color Doppler imaging, thereby facilitating measurement of tissue perfusion. We evaluated the efficacy of Power Doppier sonography in depicting soft-tissue hyperemia in musculoskeletal inflammatory conditions. SUBJECTS AND METHODS. Twenty-three patients with predominantly unifocal musculoskeletal symptoms were evaluated with conventional gray-scale imaging and Power Doppler sonography. The shoulder was evaluated in 14 patients, the elbow in three, and various other sites in six. For comparison purposes, the contralateral asymptomatic joint or site was examined in 17 cases. Fluid collections were aspirated in seven patients. RESULTS. Soft-tissue hyperemia was seen on Power Doppler sonograms at the symptomatic site(s) in 22 of 23 cases studied, with an appearance ranging from frank tissue blush to large, isolated peritendinous/peribursal vessels. Findings associated with hyperemia Included rotator cuff tendinitis and/or tear, bursitis, and symptomatic wrist ganglia. Findings on Power Doppler sonograms were normal in one patient who had a small, sterile hip joint effusion, and findings on subsequent scintigrams, pelvic radiographs, and CT scans were normal. CONCLUSION. Power Doppler sonography consistently shows hyperperfusion associated with musculoskeletal inflammatory disease. As such, it represents a use
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detection of soft tissue hyperemia value of Power Doppler sonography
American Journal of Roentgenology, 1994Co-Authors: Joel S Newman, Ronald S Adler, Ronald O Bude, Jonathan M. RubinAbstract:Power Doppler sonography is a new technique that offers extended dynamic range over that provided by conventional color Doppler imaging, thereby facilitating measurement of tissue perfusion. We evaluated the efficacy of Power Doppler sonography in depicting soft-tissue hyperemia in musculoskeletal inflammatory conditions.Twenty-three patients with predominantly unifocal musculoskeletal symptoms were evaluated with conventional gray-scale imaging and Power Doppler sonography. The shoulder was evaluated in 14 patients, the elbow in three, and various other sites in six. For comparison purposes, the contralateral asymptomatic joint or site was examined in 17 cases. Fluid collections were aspirated in seven patients.Soft-tissue hyperemia was seen on Power Doppler sonograms at the symptomatic site(s) in 22 of 23 cases studied, with an appearance ranging from frank tissue blush to large, isolated peritendinous/peribursal vessels. Findings associated with hyperemia included rotator cuff tendinitis and/or tear, b...
L E Derchi - One of the best experts on this subject based on the ideXlab platform.
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Power Doppler sonography: clinical applications.
European journal of radiology, 1998Co-Authors: C Martinoli, F Pretolesi, G Crespi, S Bianchi, N Gandolfo, M Valle, L E DerchiAbstract:Color Doppler imaging (CD) has had a great impact on ultrasonography (US). This technique depicts local flow by encoding an estimate of the mean Doppler frequency shift at a particular position in color. However, the choice of the mean frequency shift as the parameter for representing flow in color Doppler is somewhat arbitrary. Power Doppler ultrasound is a technique that encodes the Power in the Doppler signal in color. This parameter is fundamentally different from the mean frequency shift. The frequency is determined by the velocity of the red blood cells, while the Power depends on the amount of blood present. Providing an image of a different property of blood flow, Power Doppler has shown several key advantages over colour Doppler, including higher sensitivity to flow, better edge definition and depiction of continuity of flow. In this paper we review the results of Power Doppler clinical studies. All relevant information available in the literature on the potential clinical applications of this technique was revised to give a detailed survey. The increased flow sensitivity and better vascular detailing of Power Doppler have been used to detect flow presence and characteristics in vessels that are poorly imaged with conventional color Doppler. The improved depiction of tissue vasculature has shown potential advantages, especially in some areas, such as the cortex of native kidneys and renal allografts, the prepuberal testis, the infant hip and the bowel wall, in which color Doppler is not sensitive enough to detect clinically important, slow and poor flow in small vessels. In inflammatory conditions, Power Doppler was valuable in depicting increased flow in vessels that are dilated because of inflammatory response. In this field, advantages have been reported in acute cholecystitis and in inflammatory states of musculoskeletal tissues. The higher sensitivity to slow flow and the improved detailing of the course of tortuous and irregular vessels made Power Doppler a promising technique to image intratumoral vessels and, thereby, to ameliorate the accuracy of color Doppler in predicting the likelihood of benign versus malignant nature of nodules. Specific flow patterns, missed at color Doppler studies, have been indicated with Power Doppler in some tumors of the liver and breast. In different settings, Power Doppler also permitted to monitor serial blood flow changes after therapy and to display them as color intensity, allowing the observer to distinguish flow changes. Although the actual role of Power Doppler in changing patient management has not been assessed yet, this technique can depict flow which was previously undetectable, and thus permits an easier and more confident diagnosis in body regions where the ultrasound signal is weak because blood vessels are small.
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Power Doppler sonography : clinical applications
European Journal of Radiology, 1998Co-Authors: C Martinoli, F Pretolesi, G Crespi, S Bianchi, N Gandolfo, M Valle, L E DerchiAbstract:Abstract Objective. Color Doppler imaging (CD) has had a great impact on ultrasonography (US). This technique depicts local flow by encoding an estimate of the mean Doppler frequency shift at a particular position in color. However, the choice of the mean frequency shift as the parameter for representing flow in color Doppler is somewhat arbitrary. Power Doppler ultrasound is a technique that encodes the Power in the Doppler signal in color. This parameter is fundamentally different from the mean frequency shift. The frequency is determined by the velocity of the red blood cells, while the Power depends on the amount of blood present. Providing an image of a different property of blood flow, Power Doppler has shown several key advantages over colour Doppler, including higher sensitivity to flow, better edge definition and depiction of continuity of flow. In this paper we review the results of Power Doppler clinical studies. Materials and Methods. All relevant information available in the literature on the potential clinical applications of this technique was revised to give a detailed survey. Results. The increased flow sensitivity and better vascular detailing of Power Doppler have been used to detect flow presence and characteristics in vessels that are poorly imaged with conventional color Doppler. The improved depiction of tissue vasculature has shown potential advantages, especially in some areas, such as the cortex of native kidneys and renal allografts, the prepuberal testis, the infant hip and the bowel wall, in which color Doppler is not sensitive enough to detect clinically important, slow and poor flow in small vessels. In inflammatory conditions, Power Doppler was valuable in depicting increased flow in vessels that are dilated because of inflammatory response. In this field, advantages have been reported in acute cholecystitis and in inflammatory states of musculoskeletal tissues. The higher sensitivity to slow flow and the improved detailing of the course of tortuous and irregular vessels made Power Doppler a promising technique to image intratumoral vessels and, thereby, to ameliorate the accuracy of color Doppler in predicting the likelihood of benign versus malignant nature of nodules. Specific flow patterns, missed at color Doppler studies, have been indicated with Power Doppler in some tumors of the liver and breast. In different settings, Power Doppler also permitted to monitor serial blood flow changes after therapy and to display them as color intensity, allowing the observer to distinguish flow changes. Conclusion. Although the actual role of Power Doppler in changing patient management has not been assessed yet, this technique can depict flow which was previously undetectable, and thus permits an easier and more confident diagnosis in body regions where the ultrasound signal is weak because blood vessels are small.
Frank Gohlke - One of the best experts on this subject based on the ideXlab platform.
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Synovial tissue of the hip at Power Doppler US: correlation between vascularity and Power Doppler US signal.
Radiology, 2002Co-Authors: M. Walther, Harry Harms, V. Krenn, S. Radke, S. Kirschner, Frank GohlkeAbstract:PURPOSE: To correlate Power Doppler ultrasonographic (US) findings of the vascularity of synovial tissue of the hip joint with the results of histopathologic examination of the same tissue to assess the value of Power Doppler US in the visualization of synovitis. MATERIALS AND METHODS: The hip joints of 24 patients with osteoarthritis (n = 15) or rheumatoid arthritis (n = 9) of the hip joint were examined with US before arthroplasty. The vascularity of the synovial membrane was classified qualitatively by using Power Doppler US. During surgery, a section of the synovial tissue examined at Power Doppler US preoperatively was resected. The vascularity of the tissue specimen was investigated and graded qualitatively by a pathologist who was not aware of the US findings. Visual qualitative grading was controlled by means of analysis of the US images and histopathologic specimens with a digital image evaluation system. Correlations between Power Doppler US and histopathologic examination findings were calculat...