Neuroimaging Clinics of North America, Aug 1, 2021
Benign or malignant thyroid nodules are common in adults. Fine needle aspiration biopsy is the go... more Benign or malignant thyroid nodules are common in adults. Fine needle aspiration biopsy is the gold standard for diagnosis. Most thyroid nodules are benign. Ultrasound imaging is the optimal noninvasive imaging modality to determine which nodules demonstrate malignant features. The American College of Radiology Thyroid Imaging Reporting and Data System committee published a standardized approach to classifying nodules on ultrasound. The ultrasound features in this system are categorized as benign, minimally suspicious, moderately suspicious, or highly suspicious for malignancy. Applying the Thyroid Imaging Reporting and Data System results in a meaningful decrease in the number of thyroid nodules biopsied.
Journal of the Mexican Federation of Radiology and Imaging
Thyroid nodules are extremely common in the adult population. Ultrasound has assumed a primary ro... more Thyroid nodules are extremely common in the adult population. Ultrasound has assumed a primary role in their evaluation but is not definitive in distinguishing benign nodules, and a biopsy is often required. Decreasing the number of biopsies is desirable from several standpoints, and multiple risk stratification systems have been proposed for this purpose. The American College of Radiology (ACR) organized a committee to devise such a system. The final white paper was published in 2017 and is known as ACR TI-RADS (Thyroid Imaging Reporting and Data System). ACR TI-RADS requires the evaluation of five basic ultrasound features of each nodule. Points are awarded in each area based on their association (or not) with malignancy. Increasing points are awarded as the association with cancer increases. These points are summed to arrive at a final ACR TI-RADS score of 1 to 5, with an increased likelihood of malignancy as the number increases. Specific criteria for biopsy, follow-up, or no further action are outlined for each of the scores. This article will discuss the epidemiology and pathology of thyroid nodules then provide the reader with a detailed description of ACR TI-RADS and how to apply it practically.
Carotid ultrasonography (US) is most commonly performed to identify potential areas of flow-limit... more Carotid ultrasonography (US) is most commonly performed to identify potential areas of flow-limiting stenosis in the internal carotid artery. Identification of stenosis and unstable plaque is important because these entities are leading predictors of stroke, the fourth most common cause of death in the United States. However, US can detect other important but less common vascular pathologies if proper techniques and nuances of these entities are understood.In this article, we discuss the US appearance of abnormalities involving the carotid, vertebral, subclavian, and innominate arteries as well as the key clinical components of each diagnosis. These include congenital variants, dissection, stenosis, and vasculopathy. In addition, correlation of US findings with both magnetic resonance imaging and computed tomography more comprehensively demonstrates the complementary nature of these imaging modalities.
This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of ... more This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of portal vein thrombosis. Two hundred fifteen patients were studied with color Doppler imaging to determine patency of the main portal vein. Sonographic findings were confirmed in 75 patients, aged 19 to 66 years Correlation with angiography was obtained in 13 patients, and surgical correlation was obtained in the remaining 62. Nine patients had portal vein thrombosis on the basis of these gold standards. Sonograms were classified as showing either patency or thrombosis, depending on the ability to show color flow within the main portal vein. Agreement between sonography and angiography or surgery was found in 69 patients (61 patent, eight thrombosed). One patient with a patent portal vein at sonography was found to have a thrombosed vessel at surgery, whereas five patients without portal venous flow at sonography had patent vessels at angiography (one patient) or surgery (four patients). Overall sensitivity and specificity for detection of portal vein thrombosis were
(ACR) developed a standardized classification system of nodules, the Thyroid Imaging and Reportin... more (ACR) developed a standardized classification system of nodules, the Thyroid Imaging and Reporting Data System (ACR TI-RADS) to stratify the malignant risk associated with thyroid nodules [5, 6]. Because no single sonographic feature of a thyroid nodule is sufficiently sensitive or specific for malignancy, the ACR TI-RADS, like most such systems, looks at multiple features of each nodule and arrives at a risk stratification score to determine whether biopsy is warranted. US findings associated with malignancy risk in the ACR TI-RADS system include composition, echogenicity, shape, margin, and presence of echogenic foci. These features and nodule size are factored into the ACR TI-RADS to determine whether biopsy or follow-up US examination is warranted. In the ACR TI-RADS, three types of echogenic foci are associated with malignancy: macrocalcifications, peripheral calci
Radiographics : a review publication of the Radiological Society of North America, Inc, 2017
Fetal growth restriction is commonly defined as an estimated fetal weight (EFW) that is below the... more Fetal growth restriction is commonly defined as an estimated fetal weight (EFW) that is below the 10th percentile for gestational age. It is associated with an increased risk of intrauterine demise, neonatal morbidity, and neonatal death; therefore, antenatal detection and surveillance with the optimization of delivery timing are necessary to improve pregnancy outcomes. If the estimated due date has been verified and the EFW is below the 10th percentile for gestational age, the underlying cause should be investigated, since the clinical management, outcome, and counseling options are largely dependent on the cause of the growth restriction. Serial ultrasonography (US) for the evaluation of fetal growth and umbilical artery Doppler velocimetry are used to guide pregnancy management decisions. This article describes the accurate US detection and surveillance of fetal growth restriction, discusses the current obstetric and radiology literature regarding the use of Doppler velocimetry i...
Objective. To familiarize practitioners with different sonographic manifestations of renal artery... more Objective. To familiarize practitioners with different sonographic manifestations of renal artery compromise and the sonographic techniques for renal artery imaging. Methods. Approximately 1500 examinations evaluating for renal artery disease are performed in our vascular laboratory every year. Most of the patients have the symptoms of hypertension (possibly related to renovascular etiology) and renal insufficiency. From our cumulative experience, the optimal scanning techniques are defined for each renal artery, for extrarenal versus intrarenal vascular evaluation, and for patients with different body habitus. We have also tabulated our technical success rate. Cases with sonographic evidence of renal artery compromise are identified. The validity, sensitivity, and specificity of different parameters are examined. Results. We achieve an approximately 75% to 80% success rate in obtaining technically adequate studies. We have not found the tardus-parvus waveform evaluation to be as valuable as direct interrogation of the renal artery. Conclusions. Duplex/color Doppler sonography serves a vital role in the diagnosis of renal artery stenosis and occlusion; it has an excellent correlation with contrastenhanced angiography. It is also used for intraoperative or postrevascularization surveillance to show evidence of recurring stenosis, thrombosis, and other complications.
The Scientific Board of the California Medical Association presents the following inventory of it... more The Scientific Board of the California Medical Association presents the following inventory of items of progress in radiology. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established both as to scientific fact and important clinical significance. The items are presented in simple epitome and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, research workers, or scholars to stay abreast of these items of progress in radiology that have recently achieved a substantial degree of authoritative acceptance, whether in their own field of special interest or another.The items of progress listed below were selected by the Advisory Panel to the Section on Radiology of the California Medical Association, and the summaries were prepared under its direction.
Established Doppler parameters for carotid stenosis assessment do not reflect North American Symp... more Established Doppler parameters for carotid stenosis assessment do not reflect North American Symptomatic Carotid Endarterectomy Trial (NASCET)-style methodology. We derived a Doppler parameter, termed sonographic NASCET index (SNI), and hypothesized that the SNI would provide greater angiographic correlation and better accuracy in predicting stenosis of 70% or greater than that of currently used peak systolic velocity (PSV) measurements. Inclusion criteria of angiographically proved carotid stenoses of 40-95% and measured proximal and distal internal carotid artery Doppler PSV values were established. Occlusions and near occlusions were specifically excluded. Doppler and angiographic data meeting the inclusion criteria from 32 carotid bifurcations were identified; actual angiographic stenoses ranged 40-89%. SNI values were calculated for each vessel. PSV and SNI were correlated with angiography by using linear regression analysis. Accuracies of SNI and PSV in predicting stenosis of ...
Cranial sonography revealed cerebral hemorrhage in three of seven neonates with erythroblastosis ... more Cranial sonography revealed cerebral hemorrhage in three of seven neonates with erythroblastosis fetalis. Among the three infants with hemorrhage, one was 28 weeks gestational age and experienced germinal matrix hemorrhage with ventricular extension, a finding typical of cerebroventricular hemorrhage in the premature population. The other two infants with intracranial hemorrhage were more gestationally mature, and extensive intraparenchymal cerebral hemorrhages were found at sonography. These hematomas were peripheral in location and one was multifocal. Computed tomography (CT) further revealed hemorrhages in both neonates to be multifocal and in close proximity to the pia-arachnoid. In one case, the hemorrhage appeared to extend centripetally and rupture into the ventricular system. The high incidence, severity, and unusual appearance of intracranial hemorrhages in neonates with erythroblastosis fetalis has not been previously emphasized in the radiologic literature. In severe case...
Twenty-four patients with ventricular septa are discussed. Seventeen patients had septa acquired ... more Twenty-four patients with ventricular septa are discussed. Seventeen patients had septa acquired during the neonatal period and seven exhibited septations at birth (cogenital septa). Among the acquired septa, there were true intraventricular septa and septa that originated outside the ventricles but later became part of the ventricular system (pseudosepta). Pseudosepta originate in necrotic, cavitating periventricular white matter that, in temporal sequence, becomes ventricularized. Serial use of cranial sonography provided important information about the pathologic mechanisms that govern the development of septa. Intraventricular hemorrhage and infection are the major causes of true intraventricular septa, while peri ventricular leukomalacia serves as primary cause of pseudosepta. Sonography is the diagnostic method of choice. Septa are associated with a high incidence (62%) of shunt failure.
Conclusion: After detection of a carotid bruit in a patient with type II diabetes the risk for an... more Conclusion: After detection of a carotid bruit in a patient with type II diabetes the risk for an initial stroke within 2 years is six times that in a patient with type II diabetes without a carotid bruit. Summary: The Fremantle Diabetes Study is an observational, prospective, community based study of diabetes in western Australia. Between 1993 and 1996, 1081 patients with type II diabetes and no history of cerebrovascular disease were recruited and observed until the end of January 2002. Cox proportional hazards models were used to identify significant cerebrovascular risk factors for stroke and to determine whether carotid bruit was an independent predictor of first stroke in patients with type II diabetes. After study entry, 134 patients (11.3%) developed a first stroke at a mean of 6.5 Ï® 2.2 years of follow-up. In the first 2 years after entering the study, a first stroke occurred in 45 patients (3.8%). After adjustment for cardiovascular risk factors and other potentially confounding variables, first stroke in the first 2 years after study entry was strongly predicted by the presence of carotid bruit (hazard ratio, 6.7; 95% confidence interval, 3.0-14.9; P Ͻ .001). After 2 years of study observation, first stroke was not associated with carotid bruit (P Ï .97). Both diastolic blood pressure and age were also determinants of first stroke in the first 2 years after study entry. Two years after study entry, age, atrial fibrillation or flutter, and microalbuminuria were independent predictors of stroke. Comment: It might be concluded that patients with type II diabetes and carotid bruit compose a subgroup who will derive benefit from prophylactic carotid endarterectomy. However, the authors did not report the degree of carotid stenosis in their patients, and it is not clear that all strokes involved the extracranial cervical carotid artery. Clearly the data argue for aggressive risk factor management in patients with type II diabetes and a carotid bruit. The data, however, do not enable one to conclude that patients with a carotid bruit and type II diabetes will benefit from prophylactic carotid endarterectomy. Carotid artery stenosis: Gray-scale and Doppler ultrasound diagnosis.
Graefe's Archive for Clinical and Experimental Ophthalmology, 2009
Background-It is challenging for the current Doppler imaging to detect blood flow in small retina... more Background-It is challenging for the current Doppler imaging to detect blood flow in small retinal vessels. Power Doppler, with its high sensitivity to detect minimal blood flow, can be used with spectral Doppler to measure blood velocity in small vessels of the eye and orbit. Methods-Sixteen eyes of twelve normal pigmented rabbits were studied, using a dedicated small animal, high-resolution imaging unit (Vevo 770) and 17.6 MHz ultrasound probe. Spectral Doppler
Two patients with multifocal idiopathic fibrosclerosis and sclerosing cholangitis developed bilia... more Two patients with multifocal idiopathic fibrosclerosis and sclerosing cholangitis developed biliary obstruction due to a fibrotic pancreatic pseudotumor. The masslike fibrosis mimicked pancreatic carcinoma on sonography and cholangiopancreatography. In one patient sonography was successfully used to assess the response of the pseudotumor to corticosteroid therapy.
This study was undertaken to assess the significance of diastolic flow reversal seen on duplex Do... more This study was undertaken to assess the significance of diastolic flow reversal seen on duplex Doppler sonograms of patients with renal transplant dysfunction. Earlier studies have evaluated the causes of increased vascular resistance in renal transplants. None, however, have investigated specifically the subset of patients in whom impedance in the renal microcirculation has increased to the degree that retrograde arterial flow is present. In our series, 533 consecutive scans in 270 patients were reviewed. The patients were referred for evaluation of renal transplant dysfunction during a 25-month period. Doppler samples were obtained from main, segmental, and, when possible, arcuate arteries. An episode of reversed diastolic flow was identified in nine patients. Correlation was made with clinical, laboratory, histologic (biopsy in six patients, nephrectomy in three patients), and imaging studies (DTPA scintigraphy in seven patients, angiography in one patient). On the basis of histologic and nephrectomy results, we determined that among the nine patients, four had acute tubular necrosis, three had acute rejection, and two had renal vein thrombosis. One of these patients had both severe rejection and renal vein thrombosis. One additional patient had neither biopsy nor nephrectorny and was not included in the diagnostic groups listed here.
Neuroimaging Clinics of North America, Aug 1, 2021
Benign or malignant thyroid nodules are common in adults. Fine needle aspiration biopsy is the go... more Benign or malignant thyroid nodules are common in adults. Fine needle aspiration biopsy is the gold standard for diagnosis. Most thyroid nodules are benign. Ultrasound imaging is the optimal noninvasive imaging modality to determine which nodules demonstrate malignant features. The American College of Radiology Thyroid Imaging Reporting and Data System committee published a standardized approach to classifying nodules on ultrasound. The ultrasound features in this system are categorized as benign, minimally suspicious, moderately suspicious, or highly suspicious for malignancy. Applying the Thyroid Imaging Reporting and Data System results in a meaningful decrease in the number of thyroid nodules biopsied.
Journal of the Mexican Federation of Radiology and Imaging
Thyroid nodules are extremely common in the adult population. Ultrasound has assumed a primary ro... more Thyroid nodules are extremely common in the adult population. Ultrasound has assumed a primary role in their evaluation but is not definitive in distinguishing benign nodules, and a biopsy is often required. Decreasing the number of biopsies is desirable from several standpoints, and multiple risk stratification systems have been proposed for this purpose. The American College of Radiology (ACR) organized a committee to devise such a system. The final white paper was published in 2017 and is known as ACR TI-RADS (Thyroid Imaging Reporting and Data System). ACR TI-RADS requires the evaluation of five basic ultrasound features of each nodule. Points are awarded in each area based on their association (or not) with malignancy. Increasing points are awarded as the association with cancer increases. These points are summed to arrive at a final ACR TI-RADS score of 1 to 5, with an increased likelihood of malignancy as the number increases. Specific criteria for biopsy, follow-up, or no further action are outlined for each of the scores. This article will discuss the epidemiology and pathology of thyroid nodules then provide the reader with a detailed description of ACR TI-RADS and how to apply it practically.
Carotid ultrasonography (US) is most commonly performed to identify potential areas of flow-limit... more Carotid ultrasonography (US) is most commonly performed to identify potential areas of flow-limiting stenosis in the internal carotid artery. Identification of stenosis and unstable plaque is important because these entities are leading predictors of stroke, the fourth most common cause of death in the United States. However, US can detect other important but less common vascular pathologies if proper techniques and nuances of these entities are understood.In this article, we discuss the US appearance of abnormalities involving the carotid, vertebral, subclavian, and innominate arteries as well as the key clinical components of each diagnosis. These include congenital variants, dissection, stenosis, and vasculopathy. In addition, correlation of US findings with both magnetic resonance imaging and computed tomography more comprehensively demonstrates the complementary nature of these imaging modalities.
This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of ... more This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of portal vein thrombosis. Two hundred fifteen patients were studied with color Doppler imaging to determine patency of the main portal vein. Sonographic findings were confirmed in 75 patients, aged 19 to 66 years Correlation with angiography was obtained in 13 patients, and surgical correlation was obtained in the remaining 62. Nine patients had portal vein thrombosis on the basis of these gold standards. Sonograms were classified as showing either patency or thrombosis, depending on the ability to show color flow within the main portal vein. Agreement between sonography and angiography or surgery was found in 69 patients (61 patent, eight thrombosed). One patient with a patent portal vein at sonography was found to have a thrombosed vessel at surgery, whereas five patients without portal venous flow at sonography had patent vessels at angiography (one patient) or surgery (four patients). Overall sensitivity and specificity for detection of portal vein thrombosis were
(ACR) developed a standardized classification system of nodules, the Thyroid Imaging and Reportin... more (ACR) developed a standardized classification system of nodules, the Thyroid Imaging and Reporting Data System (ACR TI-RADS) to stratify the malignant risk associated with thyroid nodules [5, 6]. Because no single sonographic feature of a thyroid nodule is sufficiently sensitive or specific for malignancy, the ACR TI-RADS, like most such systems, looks at multiple features of each nodule and arrives at a risk stratification score to determine whether biopsy is warranted. US findings associated with malignancy risk in the ACR TI-RADS system include composition, echogenicity, shape, margin, and presence of echogenic foci. These features and nodule size are factored into the ACR TI-RADS to determine whether biopsy or follow-up US examination is warranted. In the ACR TI-RADS, three types of echogenic foci are associated with malignancy: macrocalcifications, peripheral calci
Radiographics : a review publication of the Radiological Society of North America, Inc, 2017
Fetal growth restriction is commonly defined as an estimated fetal weight (EFW) that is below the... more Fetal growth restriction is commonly defined as an estimated fetal weight (EFW) that is below the 10th percentile for gestational age. It is associated with an increased risk of intrauterine demise, neonatal morbidity, and neonatal death; therefore, antenatal detection and surveillance with the optimization of delivery timing are necessary to improve pregnancy outcomes. If the estimated due date has been verified and the EFW is below the 10th percentile for gestational age, the underlying cause should be investigated, since the clinical management, outcome, and counseling options are largely dependent on the cause of the growth restriction. Serial ultrasonography (US) for the evaluation of fetal growth and umbilical artery Doppler velocimetry are used to guide pregnancy management decisions. This article describes the accurate US detection and surveillance of fetal growth restriction, discusses the current obstetric and radiology literature regarding the use of Doppler velocimetry i...
Objective. To familiarize practitioners with different sonographic manifestations of renal artery... more Objective. To familiarize practitioners with different sonographic manifestations of renal artery compromise and the sonographic techniques for renal artery imaging. Methods. Approximately 1500 examinations evaluating for renal artery disease are performed in our vascular laboratory every year. Most of the patients have the symptoms of hypertension (possibly related to renovascular etiology) and renal insufficiency. From our cumulative experience, the optimal scanning techniques are defined for each renal artery, for extrarenal versus intrarenal vascular evaluation, and for patients with different body habitus. We have also tabulated our technical success rate. Cases with sonographic evidence of renal artery compromise are identified. The validity, sensitivity, and specificity of different parameters are examined. Results. We achieve an approximately 75% to 80% success rate in obtaining technically adequate studies. We have not found the tardus-parvus waveform evaluation to be as valuable as direct interrogation of the renal artery. Conclusions. Duplex/color Doppler sonography serves a vital role in the diagnosis of renal artery stenosis and occlusion; it has an excellent correlation with contrastenhanced angiography. It is also used for intraoperative or postrevascularization surveillance to show evidence of recurring stenosis, thrombosis, and other complications.
The Scientific Board of the California Medical Association presents the following inventory of it... more The Scientific Board of the California Medical Association presents the following inventory of items of progress in radiology. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established both as to scientific fact and important clinical significance. The items are presented in simple epitome and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, research workers, or scholars to stay abreast of these items of progress in radiology that have recently achieved a substantial degree of authoritative acceptance, whether in their own field of special interest or another.The items of progress listed below were selected by the Advisory Panel to the Section on Radiology of the California Medical Association, and the summaries were prepared under its direction.
Established Doppler parameters for carotid stenosis assessment do not reflect North American Symp... more Established Doppler parameters for carotid stenosis assessment do not reflect North American Symptomatic Carotid Endarterectomy Trial (NASCET)-style methodology. We derived a Doppler parameter, termed sonographic NASCET index (SNI), and hypothesized that the SNI would provide greater angiographic correlation and better accuracy in predicting stenosis of 70% or greater than that of currently used peak systolic velocity (PSV) measurements. Inclusion criteria of angiographically proved carotid stenoses of 40-95% and measured proximal and distal internal carotid artery Doppler PSV values were established. Occlusions and near occlusions were specifically excluded. Doppler and angiographic data meeting the inclusion criteria from 32 carotid bifurcations were identified; actual angiographic stenoses ranged 40-89%. SNI values were calculated for each vessel. PSV and SNI were correlated with angiography by using linear regression analysis. Accuracies of SNI and PSV in predicting stenosis of ...
Cranial sonography revealed cerebral hemorrhage in three of seven neonates with erythroblastosis ... more Cranial sonography revealed cerebral hemorrhage in three of seven neonates with erythroblastosis fetalis. Among the three infants with hemorrhage, one was 28 weeks gestational age and experienced germinal matrix hemorrhage with ventricular extension, a finding typical of cerebroventricular hemorrhage in the premature population. The other two infants with intracranial hemorrhage were more gestationally mature, and extensive intraparenchymal cerebral hemorrhages were found at sonography. These hematomas were peripheral in location and one was multifocal. Computed tomography (CT) further revealed hemorrhages in both neonates to be multifocal and in close proximity to the pia-arachnoid. In one case, the hemorrhage appeared to extend centripetally and rupture into the ventricular system. The high incidence, severity, and unusual appearance of intracranial hemorrhages in neonates with erythroblastosis fetalis has not been previously emphasized in the radiologic literature. In severe case...
Twenty-four patients with ventricular septa are discussed. Seventeen patients had septa acquired ... more Twenty-four patients with ventricular septa are discussed. Seventeen patients had septa acquired during the neonatal period and seven exhibited septations at birth (cogenital septa). Among the acquired septa, there were true intraventricular septa and septa that originated outside the ventricles but later became part of the ventricular system (pseudosepta). Pseudosepta originate in necrotic, cavitating periventricular white matter that, in temporal sequence, becomes ventricularized. Serial use of cranial sonography provided important information about the pathologic mechanisms that govern the development of septa. Intraventricular hemorrhage and infection are the major causes of true intraventricular septa, while peri ventricular leukomalacia serves as primary cause of pseudosepta. Sonography is the diagnostic method of choice. Septa are associated with a high incidence (62%) of shunt failure.
Conclusion: After detection of a carotid bruit in a patient with type II diabetes the risk for an... more Conclusion: After detection of a carotid bruit in a patient with type II diabetes the risk for an initial stroke within 2 years is six times that in a patient with type II diabetes without a carotid bruit. Summary: The Fremantle Diabetes Study is an observational, prospective, community based study of diabetes in western Australia. Between 1993 and 1996, 1081 patients with type II diabetes and no history of cerebrovascular disease were recruited and observed until the end of January 2002. Cox proportional hazards models were used to identify significant cerebrovascular risk factors for stroke and to determine whether carotid bruit was an independent predictor of first stroke in patients with type II diabetes. After study entry, 134 patients (11.3%) developed a first stroke at a mean of 6.5 Ï® 2.2 years of follow-up. In the first 2 years after entering the study, a first stroke occurred in 45 patients (3.8%). After adjustment for cardiovascular risk factors and other potentially confounding variables, first stroke in the first 2 years after study entry was strongly predicted by the presence of carotid bruit (hazard ratio, 6.7; 95% confidence interval, 3.0-14.9; P Ͻ .001). After 2 years of study observation, first stroke was not associated with carotid bruit (P Ï .97). Both diastolic blood pressure and age were also determinants of first stroke in the first 2 years after study entry. Two years after study entry, age, atrial fibrillation or flutter, and microalbuminuria were independent predictors of stroke. Comment: It might be concluded that patients with type II diabetes and carotid bruit compose a subgroup who will derive benefit from prophylactic carotid endarterectomy. However, the authors did not report the degree of carotid stenosis in their patients, and it is not clear that all strokes involved the extracranial cervical carotid artery. Clearly the data argue for aggressive risk factor management in patients with type II diabetes and a carotid bruit. The data, however, do not enable one to conclude that patients with a carotid bruit and type II diabetes will benefit from prophylactic carotid endarterectomy. Carotid artery stenosis: Gray-scale and Doppler ultrasound diagnosis.
Graefe's Archive for Clinical and Experimental Ophthalmology, 2009
Background-It is challenging for the current Doppler imaging to detect blood flow in small retina... more Background-It is challenging for the current Doppler imaging to detect blood flow in small retinal vessels. Power Doppler, with its high sensitivity to detect minimal blood flow, can be used with spectral Doppler to measure blood velocity in small vessels of the eye and orbit. Methods-Sixteen eyes of twelve normal pigmented rabbits were studied, using a dedicated small animal, high-resolution imaging unit (Vevo 770) and 17.6 MHz ultrasound probe. Spectral Doppler
Two patients with multifocal idiopathic fibrosclerosis and sclerosing cholangitis developed bilia... more Two patients with multifocal idiopathic fibrosclerosis and sclerosing cholangitis developed biliary obstruction due to a fibrotic pancreatic pseudotumor. The masslike fibrosis mimicked pancreatic carcinoma on sonography and cholangiopancreatography. In one patient sonography was successfully used to assess the response of the pseudotumor to corticosteroid therapy.
This study was undertaken to assess the significance of diastolic flow reversal seen on duplex Do... more This study was undertaken to assess the significance of diastolic flow reversal seen on duplex Doppler sonograms of patients with renal transplant dysfunction. Earlier studies have evaluated the causes of increased vascular resistance in renal transplants. None, however, have investigated specifically the subset of patients in whom impedance in the renal microcirculation has increased to the degree that retrograde arterial flow is present. In our series, 533 consecutive scans in 270 patients were reviewed. The patients were referred for evaluation of renal transplant dysfunction during a 25-month period. Doppler samples were obtained from main, segmental, and, when possible, arcuate arteries. An episode of reversed diastolic flow was identified in nine patients. Correlation was made with clinical, laboratory, histologic (biopsy in six patients, nephrectomy in three patients), and imaging studies (DTPA scintigraphy in seven patients, angiography in one patient). On the basis of histologic and nephrectomy results, we determined that among the nine patients, four had acute tubular necrosis, three had acute rejection, and two had renal vein thrombosis. One of these patients had both severe rejection and renal vein thrombosis. One additional patient had neither biopsy nor nephrectorny and was not included in the diagnostic groups listed here.
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Papers by Edward Grant