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BACKGROUND: Fifteen to thirty percent of all patients with metastatic breast cancer (MBC) develop brain metastases (BCBMs). Recently, the antibody-drug conjugates (ADCs) sacituzumab govitecan (SG) and trastuzumab deruxtecan (T-DXd) have shown to be highly effective in the treatment of MBC. However, there are only limited data whether these macromolecules are also effective in patients with BCBMs. We therefore aimed to examine the efficacy of SG and T-DXd in patients with stable and active BCBMs in a multicenter real-world analysis. PATIENTS AND METHODS: Female patients with stable or active BCBMs who were treated with either SG or T-DXd at three breast centers in Germany before 30 June 2023 were included. As per local clinical praxis, chemotherapy efficacy was evaluated by whole-body computed tomography and cranial magnetic resonance imaging at baseline and at least every 3 months according to local standards. Growth dynamics of BCBMs were assessed by board-certified neuroradiologists. RESULTS: Of 26 patients, with a median of 2.5 prior therapy lines in the metastatic setting (range 2-15), 12 (43%) and 16 (57%) patients received SG and T-DXd, respectively. Out of the 12 patients who received SG, 2 (17%) were subsequently treated with T-DXd. Five out of 12 (42%) and 5 out of 16 (31%) patients treated with SG and T-DXd, respectively, had active BCBMs at treatment initiation. The intracranial disease control rate was 42% [95% confidence interval (CI) 13% to 71%] for patients treated with SG and 88% (95% CI 72% to 100%) for patients treated with T-DXd. After a median follow-up of 12.7 months, median intracranial progression-free survival was 2.7 months (95% CI 1.6-10.5 months) for SG and 11.2 months (95% CI 7.5-23.7 months) for T-DXd. CONCLUSIONS: SG and T-DXd showed promising clinical activity in both stable and active BCBMs. Further prospective clinical studies designed to investigate the efficacy of modern ADCs on active and stable BCBMs are urgently needed.
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Anticuerpos Monoclonales Humanizados , Neoplasias Encefálicas , Neoplasias de la Mama , Camptotecina , Inmunoconjugados , Trastuzumab , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/farmacología , Persona de Mediana Edad , Trastuzumab/uso terapéutico , Trastuzumab/farmacología , Inmunoconjugados/uso terapéutico , Inmunoconjugados/farmacología , Adulto , Anciano , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Camptotecina/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Estudios RetrospectivosRESUMEN
OBJECTIVE: Longer duration of residence among immigrants to the United States, a proxy measure of acculturation, has been associated with higher subclinical atherosclerosis. South Asian immigrants are the second fastest growing immigrant group in the U.S. but little is known about the effects of acculturation with atherosclerosis in this high cardiovascular risk population. METHODS: We conducted a cross-sectional analysis using data from a community-based cohort called the Mediators of Atherosclerosis in South Asians Living in America (MASALA) study. Participants (n=900) were between ages of 40-84 years and had no existing cardiovascular disease. We developed a multi-dimensional measure of acculturation in South Asians, called traditional cultural beliefs, and measured other proxy measures of acculturation to determine whether they were associated with higher levels of subclinical atherosclerosis after controlling for socioeconomic, behavior/lifestyle, and cardiovascular risk factors. RESULTS: Mean duration of residence in the U.S. was 27±11 years and tertiles of strength of traditional cultural beliefs were examined. Longer duration of U.S. residence was associated with higher levels of coronary artery calcium even after adjustment for covariates and lifestyle mediators. The novel measure of strength of traditional cultural beliefs was associated with lower common carotid intima media thickness among those with moderate traditional beliefs only. CONCLUSIONS: These findings support the need for better conceptualization and measurement of how migration influences cultural beliefs and practices, and their subsequent influence on health behaviors and cardiovascular disease risk.
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BACKGROUND: Transcranial Doppler ultrasound (TCD) and magnetic resonance angiography (MRA) can identify intracranial atherosclerosis but have not been rigorously validated against the gold standard, catheter angiography. The WASID trial (Warfarin Aspirin Symptomatic Intracranial Disease) required performance of angiography to verify the presence of intracranial stenosis, allowing for prospective evaluation of TCD and MRA. The aims of Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis (SONIA) trial were to define abnormalities on TCD/MRA to see how well they identify 50 to 99% intracranial stenosis of large proximal arteries on catheter angiography. STUDY DESIGN: SONIA standardized the performance and interpretation of TCD, MRA, and angiography. Study-wide cutpoints defining positive TCD/MRA were used. Hard copy TCD/MRA were centrally read, blind to the results of angiography. RESULTS: SONIA enrolled 407 patients at 46 sites in the United States. For prospectively tested noninvasive test cutpoints, positive predictive values (PPVs) and negative predictive values (NPVs) were TCD, PPV 36% (95% CI: 27 to 46); NPV, 86% (95% CI: 81 to 89); MRA, PPV 59% (95% CI: 54 to 65); NPV, 91% (95% CI: 89 to 93). For cutpoints modified to maximize PPV, they were TCD, PPV 50% (95% CI: 36 to 64), NPV 85% (95% CI: 81 to 88); MRA PPV 66% (95% CI: 58 to 73), NPV 87% (95% CI: 85 to 89). For each test, a characteristic performance curve showing how the predictive values vary with a changing test cutpoint was obtained. CONCLUSIONS: Both transcranial Doppler ultrasound and magnetic resonance angiography noninvasively identify 50 to 99% intracranial large vessel stenoses with substantial negative predictive value. The Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis trial methods allow transcranial Doppler ultrasound and magnetic resonance angiography to reliably exclude the presence of intracranial stenosis. Abnormal findings on transcranial Doppler ultrasound or magnetic resonance angiography require a confirmatory test such as angiography to reliably identify stenosis.
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Arterias Cerebrales/diagnóstico por imagen , Diagnóstico por Imagen/normas , Arteriosclerosis Intracraneal/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico , Anciano , Angiografía Cerebral/normas , Angiografía Cerebral/estadística & datos numéricos , Arterias Cerebrales/patología , Diagnóstico por Imagen/tendencias , Femenino , Humanos , Arteriosclerosis Intracraneal/patología , Angiografía por Resonancia Magnética/normas , Angiografía por Resonancia Magnética/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/terapia , Ultrasonografía Doppler Transcraneal/normas , Ultrasonografía Doppler Transcraneal/estadística & datos numéricos , Estados UnidosRESUMEN
Although abnormalities in course and geometry (tortuosity, kinking, and coiling) of the internal carotid arteries (ICA) are commonly identified, their etiology and relationship with stroke and stroke risk factors remain unclear This study assessed the clinical and ultrasonographic features of the patients with abnormalities in course and geometry of the ICA. Carotid color duplex ultrasound studies of 345 consecutive patients referred to the Neuroultrasound Lab were prospectively evaluated. Abnormalities in direction and course of the ICA were classified according to the criteria of Weibel-Fields and Metz modified by the authors. Kinking was categorized as mild (> 60 degrees), moderate (30 degrees-60 degrees), and severe (< 30 degrees). Carotid abnormalities (CA) were found in 85/345 (24.6%), 60/85 (70.6%) were female. More CA were seen in females older than 60 y/o (p < 0.001), but there was no gender difference in patients 60 y/o or younger CA were bilateral in 41 patients (48%), but in those with unilateral CA, most were on the left. The most common CA was kinking (71 arteries, 56%), followed by tortuosity (48 arteries, 38%), and coiling (7 arteries, 6%). None of the atherosclerotic vascular diseases or risk factors was associated with CA. Mild atheromatous plaques predominated in patients with CA, but moderate and large plaques were more common in the others (p = 0.001). Maximal systolic velocity at the level of CA was higher in patients with kinking or coiling compared with tortuosity (p = 0.001). Lumen diameter at the level of CA was inversely correlated to the severity of CA (p < 0.001). However, carotid stenosis was equally present in all groups. This study suggests that CA have no clear importance as a stroke risk factor or marker of atherosclerotic vascular disease. Our results suggest that CA do not develop as a consequence of vascular risk factors or atherosclerotic lesions, and they are not related to ischemic stroke, TIA or the presence of carotid stenosis. In women, CA was related with advanced age. It appears that CA frequently identified by color duplex sonography are more of curiosity than a clinically significant finding.
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Enfermedades de las Arterias Carótidas/patología , Arteria Carótida Interna/anomalías , Arteria Carótida Interna/patología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/patología , Factores de Edad , Anciano , Biomarcadores , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/fisiopatología , Arteria Carótida Interna/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/patología , Estenosis Carotídea/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Accidente Cerebrovascular/fisiopatología , Ultrasonografía Doppler en ColorAsunto(s)
Hipertensión Intracraneal/cirugía , Punción Espinal , Ultrasonografía Doppler Transcraneal , Adulto , Encéfalo/irrigación sanguínea , Encéfalo/patología , Encéfalo/cirugía , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/cirugía , Hipertensión Intracraneal/diagnóstico por imagen , Hipertensión Intracraneal/etiología , Masculino , Hemorragia Subaracnoidea/complicaciones , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: To review the use of transcranial Doppler ultrasonography (TCD) and transcranial color-coded sonography (TCCS) for diagnosis. METHODS: The authors searched the literature for evidence of 1) if TCD provides useful information in specific clinical settings; 2) if using this information improves clinical decision making, as reflected by improved patient outcomes; and 3) if TCD is preferable to other diagnostic tests in these clinical situations. RESULTS: TCD is of established value in the screening of children aged 2 to 16 years with sickle cell disease for stroke risk (Type A, Class I) and the detection and monitoring of angiographic vasospasm after spontaneous subarachnoid hemorrhage (Type A, Class I to II). TCD and TCCS provide important information and may have value for detection of intracranial steno-occlusive disease (Type B, Class II to III), vasomotor reactivity testing (Type B, Class II to III), detection of cerebral circulatory arrest/brain death (Type A, Class II), monitoring carotid endarterectomy (Type B, Class II to III), monitoring cerebral thrombolysis (Type B, Class II to III), and monitoring coronary artery bypass graft operations (Type B to C, Class II to III). Contrast-enhanced TCD/TCCS can also provide useful information in right-to-left cardiac/extracardiac shunts (Type A, Class II), intracranial occlusive disease (Type B, Class II to IV), and hemorrhagic cerebrovascular disease (Type B, Class II to IV), although other techniques may be preferable in these settings.
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Ultrasonografía Doppler Transcraneal/estadística & datos numéricos , Adolescente , Adulto , Anemia de Células Falciformes/diagnóstico por imagen , Angiografía Cerebral/estadística & datos numéricos , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/etiología , Niño , Preescolar , Puente de Arteria Coronaria/efectos adversos , Ecocardiografía/estadística & datos numéricos , Femenino , Defectos del Tabique Interatrial/diagnóstico por imagen , Humanos , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Masculino , Monitoreo Fisiológico , Neurología/organización & administración , Sensibilidad y Especificidad , Accidente Cerebrovascular/diagnóstico por imagen , Hemorragia Subaracnoidea/diagnóstico por imagen , Evaluación de la Tecnología Biomédica/estadística & datos numéricos , Terapia Trombolítica , Ultrasonografía Doppler Transcraneal/normasRESUMEN
BACKGROUND AND PURPOSE: This study was designed to assess the accuracy of transcranial color-coded sonography (TCCS) as compared to magnetic resonance angiography (MRA) for detecting intracranial arterial stenosis in patients with acute cerebral ischemia. METHODS: The authors prospectively identified 120 consecutive patients admitted with acute ischemic stroke and performed both TCCS and MRA with a mean interval of 1 day. TCCS data (sampling depth, peak systolic and end diastolic angle-corrected velocity, mean angle-corrected velocity, and pulsatility index) for middle cerebral arteries (MCAs) were compared to MRA data and classified into 4 grades: normal (grade 1): normal caliber and signal; mild stenosis (grade 2): irregular lumen with reduced signal; severe stenosis (grade 3): absent signal in the stenotic segment (flow gap) and reconstituted distal signal; and possible occlusion (grade 4): absent signal. The cutoffs were chosen to maximize diagnostic accuracy. RESULTS: Interobserver agreement for MRA grading resulted in a weighted-kappa value of 0.776. The rate of poor temporal window was 37% (89/240). Doppler signals were obtained in 135 vessels, and the angle-corrected velocities (peak systolic, end diastolic, mean) were significantly different (P = .001, P = .006, and P < .001) among the MRA grades: grade 1 (100, 47, 68 cm/s), grade 2 (171, 72, 110 cm/s), grade 3 (226, 79, 134 cm/s), grade 4 (61, 26, 39 cm/s). Additionally, an angle-corrected MCA peak systolic velocity > or = 120 cm/s correlates with intracranial stenosis on MRA (grade 2 or worse) with high specificity (90.5%; 95% confidence interval = 78.5%-96.8%) and positive predictive value (93.9%) but relatively low sensitivity (66.7%; 95% confidence interval = 61.2%-69.5%) and negative predictive value (55.1%). CONCLUSION: Elevated MCA velocities on TCCS correlate with intracranial stenosis detected on MRA. An angle-corrected peak systolic velocity > or = 120 cm/s is highly specific for detecting intracranial stenosis as defined by significant MRA abnormality.
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Arteriopatías Oclusivas/diagnóstico , Enfermedades Arteriales Cerebrales/diagnóstico , Angiografía por Resonancia Magnética , Accidente Cerebrovascular/diagnóstico , Ultrasonografía Doppler Transcraneal , Enfermedad Aguda , Anciano , Análisis de Varianza , Arteriopatías Oclusivas/fisiopatología , Velocidad del Flujo Sanguíneo , Enfermedades Arteriales Cerebrales/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Accidente Cerebrovascular/fisiopatologíaRESUMEN
BACKGROUND AND PURPOSE: The authors attempt to determine whether hemodynamically significant extracranial internal carotid artery (ICA) lesions correlate with the severity of first-ever hemispheric ischemic stroke. METHODS: Carotid duplex was used to evaluate carotid arteries. The National Institutes of Health Stroke Scale was used to describe the severity of the stroke and was stratified as follows: 1-6 = mild, 7-15 = moderate, > 15 = severe. Duplex findings were categorized according to velocity criteria into < 50% stenosis if ICA peak systolic velocity (PSV) (cm/s) < 140 and > 50% stenosis if ICA PSV > 140 or ratio of ICA and common carotid artery in PSV > 2. No detectable flow at ICA was considered occlusion. Stroke subtype was classified according to TOAST criteria. RESULTS: Two hundred nineteen consecutive patients were enrolled, including 127 with mild, 65 with moderate, and 27 with severe stroke. The prevalence of ICA stenosis > 50% in each group was 3.6%, 1.4%, 0.9%, respectively. Two patients in the severe group had total ICA occlusion. The overall prevalence of significant ICA lesions was 6.8%. CONCLUSIONS: There is no positive correlation of stroke severity with the severity of duplex findings, which may be due to low prevalence of significant ICA lesions or other stroke mechanisms. Most of the patients had mild stroke, and the majority had ICA stenosis < 50%. Small-vessel occlusion tended to have mild severity of stroke. Intracranial artery lesions or other factors causing stroke in Taiwanese should be investigated. Given the low incidence of significant extracranial carotid disease in symptomatic Taiwanese stroke patients, routine screening of symptomatic Taiwanese for extracranial carotid artery disease does not provide enough information to determine stroke mechanism, and transcranial Doppler should be added to the screening tests.
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Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Enfermedad Aguda , Anciano , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/epidemiología , Arteria Carótida Interna/diagnóstico por imagen , Distribución de Chi-Cuadrado , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Taiwán/epidemiología , Ultrasonografía Doppler DúplexRESUMEN
Cerebral vasoreactivity can be studied with transcranial Doppler (TCD) by monitoring CO2-induced middle cerebral artery (MCA) velocity changes. Expected MCA mean velocity (Vm) changes due to changes in end-expiratory CO2 (EE-CO2) are established, but reactivity of common carotid artery (CCA) volume flow rate (VFR) has not been extensively reported. The authors assess the relationship between MCA Vm, CCA VFR, and EE-CO2. Ten normal individuals without cerebrovascular disease and with CCA diameters of more than 3.0 mm were studied. CCA VFR was obtained by Color Velocity Imaging Quantification and Ipsilateral MCA Vm by standard TCD methods. Each side was studied before, during, and after inhalation of 5% CO2. EE-CO2, blood pressure, and pulse rate were monitored. Four women and 6 men with mean age of 36 years were included. Significant correlations between MCA Vm and EE-CO2, CCA VFR and EE-CO2, and MCA Vm and CCA VFR were found. MCA Vm and CCA VFR increased 5.2% and 4.3% per mm Hg increase in EE-CO2, respectively. MCA Vm increased 0.3 cm/s for each ml/min increase in CCA VFR. In normal individuals, there is a direct correlation between MCA Vm, CCA VFR, and EE-CO2. Measurement of CCA VFR changes during CO2 inhalation may be an alternative method to estimate cerebral vasoreactivity when the MCA velocity cannot be obtained because of inadequate acoustic temporal windows.
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Dióxido de Carbono/administración & dosificación , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/fisiología , Arterias Cerebrales/diagnóstico por imagen , Arterias Cerebrales/fisiología , Ultrasonografía Doppler Transcraneal , Administración por Inhalación , Adulto , Velocidad del Flujo Sanguíneo , Femenino , Hemodinámica , Humanos , MasculinoRESUMEN
BACKGROUND AND PURPOSE: We examined the relationship of carotid artery lesions (CALs), with and without acoustic shadowing (AS), to incident ischemic stroke events in the Atherosclerosis Risk in Communities study cohort. METHODS: The study population consisted of 13 123 men and women aged 45 to 64 years, and free of stroke, examined during 1986-1989. Over an average follow-up time of 8.0 years, 226 incident ischemic stroke cases (thromboembolic brain infarctions) were identified and classified by a standardized protocol. Three levels of exposure were defined on the basis of the presence of B-mode ultrasound-detected CALs and AS in a 3-cm segment of the carotid arteries centered at the bifurcation. RESULTS: The hazard ratio for ischemic stroke adjusted for age, ethnicity, and study site for women with a CAL without AS, compared with those without a CAL, was 1.92 (95% CI, 1.23, 3.01), and the hazard ratio comparing those with a CAL with AS with those without a CAL was 4.01 (95% CI, 2.28, 7.06). The corresponding hazard ratios for men were 1.99 (95% CI, 1.36, 2.91) and 2.23 (95% CI, 1.32, 3.79). Although adjustment for diabetes, hypertension medication, systolic blood pressure, left ventricular hypertrophy score, fibrinogen, von Willebrand factor antigen, and smoking status attenuated these associations somewhat, when compared with no evidence of CALs, CALs with AS remained statistically significant predictors of ischemic stroke in women, while CALs without AS were predictive of ischemic stroke in men. CONCLUSIONS: B-mode ultrasound-detected CALs and AS serve as markers of atherosclerosis and thus are predictive of ischemic stroke.
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Isquemia Encefálica/diagnóstico , Calcinosis/diagnóstico , Arterias Carótidas/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico , Isquemia Encefálica/epidemiología , Estudios de Cohortes , Comorbilidad , Demografía , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Medición de Riesgo , Factores de Riesgo , Distribución por Sexo , Accidente Cerebrovascular/epidemiología , Ultrasonografía/métodos , Estados Unidos/epidemiologíaRESUMEN
GOAL: To develop a practical severity scale (Wake Forest Stroke Severity Scale [WFSSS]) to predict acute hospital outcomes and resource use after acute ischemic stroke based on the admission neurologic exam. BACKGROUND: A useful scheme enabling physicians and other health care providers to stratify stroke severity on admission to predict acute hospital outcomes and improve efficiency of inpatient care has not been described. METHODS: The study subjects consisted of 271 consecutive acute stroke patients admitted to the neurology department from July 1995 to June 1996 who were prospectively examined and whose stroke severity was classified on the basis of admission neurologic exam (level of consciousness, strength, dysphasia, neglect, and gait) as mild, moderate, or severe, based on the WFSSS. National Institutes of Health stroke scale (NIHSS) was performed early in admission (70% within 24 hours). Discharge disposition (home, inpatient rehabilitation [rehab], skilled nursing facility [SNF], or death); length of stay (LOS); and hospital charges were associated with initial stroke severity ratings using chi-square and Kruskal-Wallis tests. RESULTS: Fifty-percent (136) of strokes were classified as mild, 22% (60) as moderate, and 28% (75) as severe. Initial severity ratings were significantly related to discharge disposition, LOS, and hospital charges (all P values <.001). CONCLUSIONS: A practical clinical severity scale (WFSSS) for acute ischemic stroke patients based on admission neurologic examination predicts hospital disposition, LOS, and hospital charges, and may allow more accurate severity-adjusted comparisons among institutions.
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BACKGROUND: Thromboembolism is an infrequent but serious complication in dilated cardiomyopathy (DCM), and the role of primary preventive antithrombotic or anticoagulation therapy is undetermined. High-intensity transient signals (HITS) by Doppler ultrasound representing microemboli have been described in various clinical settings associated with increased risk of stroke. This study assessed the feasibility, reproducibility, and prevalence of HITS in patients with DCM. METHODS: Thirty patients with severely reduced left ventricular ejection fraction (< or = 35%, mean 25%) and New York Heart Association class II to III who were not receiving antithrombotic or anticoagulant therapy and 20 age-matched normal subjects were prospectively examined. Patients with atrial fibrillation, significant cardiac valvular heart disease, a history of cerebrovascular disease, and those who otherwise required antithrombotic or anticoagulation therapy were excluded. One-hour pulsed-wave Doppler recordings over the common carotid artery (CCA) were performed on 3 separate days in each subject by a single, experienced, blinded sonographer with a 4-MHz probe (TC-2000, Nicolet/EME) with a specially designed probe holder. Studies were read in a blinded, random fashion by 2 independent, experienced HITS Doppler recording readers. RESULTS: HITS in the CCA were detected in 6 (20%) of 30 patients with DCM and in 3 (15%) of 20 volunteers. This difference was not statistically significant. Intrareader and interreader reproducibility were high (kappa = 0.91 and 0.84, respectively; P <.001), whereas intrasubject reproducibility over the 3 visits was moderate to low (kappa = 0.22). There was no significant difference between HITS characteristics, that is, intensity and duration, in patients versus controls. CONCLUSIONS: The prevalence of CCA HITS in patients with clinically stable heart failure who are not receiving anticoagulation/antithrombotic therapy and are not in atrial fibrillation is low and not significantly different from normal patients. These data suggest that HITS monitoring is not a viable surrogate marker for increased thromboembolic risk in such patients with DCM.
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Cardiomiopatía Dilatada/complicaciones , Cardiomiopatía Dilatada/diagnóstico por imagen , Arteria Carótida Común/diagnóstico por imagen , Embolia Intracraneal/diagnóstico por imagen , Embolia Intracraneal/etiología , Ultrasonografía Doppler Transcraneal , Adulto , Anciano , Estudios de Factibilidad , Humanos , Embolia Intracraneal/epidemiología , Persona de Mediana Edad , Variaciones Dependientes del Observador , Prevalencia , Estudios Prospectivos , Reproducibilidad de los ResultadosRESUMEN
In this update, the main clinical applications of transcranial Doppler ultrasonography are reassessed. A specific format for technology assessment, personal experience, and an extensive review of the literature form the basis of the evaluation. The document is approved by the American Society of Neuroimaging and the Neurosonology Research Group of the World Federation of Neurology.
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Ultrasonografía Doppler Transcraneal , Encefalopatías/diagnóstico por imagen , Procedimientos Quirúrgicos Cardíacos , Trastornos Cerebrovasculares/diagnóstico por imagen , Endarterectomía Carotidea , HumanosRESUMEN
The functional equivalence of overt movements and dynamic imagery is of fundamental importance in neuroscience. Here, we investigated the participation of the neocortical motor areas in a classic task of dynamic imagery, Shepard and Metzler's mental rotation task, by time-resolved single-trial functional Magnetic Resonance Imaging (fMRI). The subjects performed the mental-rotation task 16 times, each time with different object pairs. Functional images were acquired for each pair separately, and the onset times and widths of the activation peaks in each area of interest were compared to the response times. We found a bilateral involvement of the superior parietal lobule, lateral premotor area, and supplementary motor area in all subjects; we found, furthermore, that those areas likely participate in the very act of mental rotation. We also found an activation in the left primary motor cortex, which seemed to be associated with the right-hand button press at the end of the task period.
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Mapeo Encefálico , Encéfalo/fisiología , Cognición , Neuronas/fisiología , Reconocimiento Visual de Modelos , Simulación por Computador , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Corteza Motora/fisiología , Lóbulo Parietal/fisiología , Tiempo de Reacción , Rotación , Factores de TiempoRESUMEN
Valid comparisons of functional activation volumes from fMRI and PET require accurate registration, matched spatial resolution, and if possible matched noise. We coregistered 4.0T-fMRI and PET volumes, using a series of linear and nonlinear transformations applied to the PET volumes. Because of the limited number of fMRI slices that were available, PET volumes were transformed to the fMRI space. Since 4.0T-fMRI and 4.0T-MRI volumes have significant spatial distortion due to magnet inhomogeneities, high resolution 1.5T-MRI volumes were nonlinearly transformed to 4.0T-MRI volumes as part of the transformation chain. The smoothing effects of these registration transformations were measured, in order to match the spatial resolution of the coregistered fMRI and PET volumes. Spatial resolution of the transformed PET volumes in the fMRI space was degraded by up to 60% due to the transformation process. Due to both the image acquisition characteristics and the coregistration process, the transformed PET volumes had a spatial resolution that was lower than that of tMRI. Therefore, significant smoothing of fMRI volumes was necessary to match their spatial resolution with that of the transformed PET volumes. Matching the spatial resolution of the fMRI volumes to those of the transformed PET volumes was achieved by matching the shape of their point spread functions. In order to do this, Gaussian kernels were employed to smooth the fMRI volumes. We were unable to simultaneously match the resolution and noise of fMRI and PET signals in the motor cortex. Activation maps derived from transformed PET and smoothed fMRI volumes were compared. Contralateral motor cortex was active in all modalities but there were large variations in the size of the activated region and its signal to noise ratio across BOLD, FAIR, and PET images within each subject. Nevertheless, the relative CBF changes measured by FAIR were consistent with those determined by PET.
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Encéfalo/anatomía & histología , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada de Emisión , Fenómenos Biofísicos , Biofisica , Estudios de Evaluación como Asunto , Humanos , Procesamiento de Imagen Asistido por Computador , Radioisótopos de OxígenoRESUMEN
The reproducibility of activation patterns in the whole brain obtained by functional magnetic resonance imaging (fMRI) experiments at 4 Tesla was studied with a simple finger-opposition task. Six subjects performed three runs in one session, and each run was analyzed separately with the t-test as a univariate method and Fisher's linear discriminant analysis as a multivariate method. Detrending with a first- and third-order polynomial as well as logarithmic transformation as preprocessing steps for the t-test were tested for their impact on reproducibility. Reproducibility across the whole brain was studied by using scatter plots of statistical values and calculating the correlation coefficient between pairs of activation maps. In order to compare reproducibility of "activated" voxels across runs, subjects and models, 2% of all voxels in the brain with the highest statistical values were classified as activated. The analysis of reproducible activated voxels was performed for the whole brain and within regions of interest. We found considerable variability in reproducibility across subjects, regions of interest, and analysis methods. The t-test on the linear detrended data yielded better reproducibility than Fisher's linear discriminant analysis, and therefore seems to be a robust although conservative method. Preliminary data indicate that these modeling results may be reversed by preprocessing to reduce respiratory and cardiac physiological noise effects. The reproducibility of both the position and number of activated voxels in the sensorimotor cortex was highest, while that of the supplementary motor area was much lower, with reproducibility of the cerebellum falling in between the other two areas.
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Mapeo Encefálico , Imagen por Resonancia Magnética/normas , Modelos Neurológicos , Corteza Motora/fisiología , Adulto , Femenino , Dedos/fisiología , Humanos , Masculino , Análisis Multivariante , Lóbulo Occipital/fisiología , Reproducibilidad de los Resultados , Umbral Sensorial/fisiología , Corteza Somatosensorial/fisiologíaRESUMEN
The aim was to test the accuracy of muscle volume measurements with a new 3-dimensional (3-D) ultrasound system, which allows a freehand scanning of the transducer with an improved quality of the ultrasound images and therefore the outlines of the muscles. Five resected cadaveric hand muscles were insonated and the muscle volumes calculated by 3-D reconstructions of the acquired 2-D ultrasound sections. Intra-reader, inter-reader and follow-up variability were calculated, as well as the volume of the muscle tissue measured by water displacement. In the results, 3-D ultrasound and water displacement measurements showed an average deviation of 10.1%; Data of 3-D ultrasound measurements were: intra-reader variability 2.8%; inter-reader variability 2.4% and follow-up variability 2.3%. 3-D measurements of muscle volume are valid and reliable. Serial sonographic measurements of muscle may be able to quantitate changes in muscle volume that occur in disease and recovery.
Asunto(s)
Músculo Esquelético/anatomía & histología , Músculo Esquelético/diagnóstico por imagen , Cadáver , Humanos , Técnicas In Vitro , Ultrasonografía/métodosRESUMEN
The internal jugular (IJ) valve is the only valve between the heart and the brain, preventing venous reflux into the IJ vein. Internal jugular valve competence has been tested by IJ venography. Doppler ultrasonography of the IJ vein and M-mode ultrasonography of the IJ valve, and color flow imaging (CFI) of the IJ vein. However, interpretation of venous Doppler and CFI is difficult, and venography is invasive. The purpose of this study was to evaluate the feasibility of a new dynamic method to test IJ valve competency, and to review the literature regarding the potential clinical importance of this pathophysiology. Ten patients had intravenous injection of agitated air and saline during Valsalva maneuver with B-mode monitoring and CFI of the right IJ vein. Contrast bubbles were clearly identified refluxing into the right IJ vein in 50% of patients. Air contrast studies more often showed IJ valve incompetence than CFI. Bubbles appeared in the IJ vein within 19.2 sec and persisted up to 282 sec. Bubble aggregation was also observed. There was no correlation between positive bubbles and the presence of spontaneous echo contrast on baseline B-mode imaging. Air contrast ultrasound venography (ACUV) is a new noninvasive method to assess competency of the IJ valves. This technique is feasible, appears to be more sensitive than CFI, and adds a new dimension to the study of the venous system in cerebrovascular disease. Potential clinical application includes evaluation of patients with increased central venous pressure, those with morning headaches, and those on positive end-expiratory pressure ventilators.
Asunto(s)
Venas Yugulares/diagnóstico por imagen , Venas Yugulares/fisiopatología , Ultrasonografía Doppler Dúplex/métodos , Anciano , Aire , Estudios de Factibilidad , Femenino , Humanos , Venas Yugulares/anatomía & histología , Masculino , Cloruro de Sodio/administración & dosificación , Maniobra de ValsalvaRESUMEN
Functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG) were used to study the relationships between lateralized auditory perception in humans and the contralaterality of processing in auditory cortex. Subjects listened to rapidly presented streams of short FM-sweep tone bursts to detect infrequent, slightly deviant tone bursts. The stimulus streams consisted of either monaural stimuli to one ear or the other or binaural stimuli with brief interaural onset delays. The onset delay gives the binaural sounds a lateralized auditory perception and is thought to be a key component of how our brains localize sounds in space. For the monaural stimuli, fMRI revealed a clear contralaterality in auditory cortex, with a contralaterality index (contralateral activity divided by the sum of contralateral and ipsilateral activity) of 67%. In contrast, the fMRI activations from the laterally perceived binaural stimuli indicated little or no contralaterality (index of 51%). The MEG recordings from the same subjects performing the same task converged qualitatively with the fMRI data, confirming a clear monaural contralaterality, with no contralaterality for the laterally perceived binaurals. However, the MEG monaural contralaterality (55%) was less than the fMRI and decreased across the several hundred millisecond poststimulus time period, going from 57% in the M50 latency range (20-70 ms) to 53% in the M200 range (170-250 ms). These data sets provide both quantification of the degree of contralaterality in the auditory pathways and insight into the locus and mechanism of the lateralized perception of spatially lateralized sounds.
Asunto(s)
Percepción Auditiva/fisiología , Mapeo Encefálico , Corteza Cerebral/fisiología , Localización de Sonidos/fisiología , Percepción Espacial/fisiología , Estimulación Acústica , Adulto , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética/métodos , Magnetoencefalografía/métodos , Tiempo de ReacciónRESUMEN
PURPOSE: Three-dimensional (3D) B-mode ultrasound imaging is now possible using a magnetic sensor data acquisition system to localise data points, allowing free-hand scanning. We report the first use of this freehand scanning system for insonation of the orbit. METHODS: We insonated 10 orbits in 5 volunteers (all men; mean age 37 years) with an Acuson 128XP ultrasound system and a 7.5 MHz transducer. Power-Doppler was used to image vascular structures. Data were acquired using a new magnetic sensor system with detectors mounted on the transducer. Free-hand scanning was done using sweeping or fan-like and linear movements over 20-30 s to cover the orbit, with retrospective measurements of orbital structures. A 3D reconstruction was performed via an external workstation. RESULTS: All orbits were adequately imaged by one data acquisition. Selected intraorbital structures were identified and their course followed, including optic nerve and central vessels, as well as short and long ciliary vessels. The mean transverse area of the optic nerve was 5.6 +/- 1.1 mm2; the diameter of the optic nerve was 3.0 +/- 0.3 mm. The lateral rectus muscle was clearly seen, with a mean diameter of 4.9 +/- 0.3 mm, at the level of optic nerve head. CONCLUSION: Three-dimensional ultrasound of the orbit allows imaging of the location, course and relationships of intraorbital vessels, the optic nerve and the lateral rectus muscles with one data acquisition, as well as quantitative measurements not possible with 2D images alone. This method allows rapid, free-hand data acquisition, with a multitude of potential clinical applications.