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1.
Eur Radiol ; 26(6): 1818-25, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26334511

RESUMEN

OBJECTIVES: To compare a modified T1-weighted 3D TSE black-blood sequence with sub-millimetre resolution (T1-mVISTA) with a magnetization-prepared rapid gradient echo (MP-RAGE) sequence for the diagnosis of cerebral malignomas. METHODS: Forty-six patients with known or suspected intracranial tumours and 15 control patients were included in this retrospective study. All patients underwent T1-mVISTA (0.75-mm isotropic resolution, 4:43 min) and MP-RAGE (0.8-mm isotropic resolution, 4:46 minutes) at 3-Tesla in random order after application of contrast agent. Two experienced radiologists determined the number of lesions. Maximum diameter, diagnostic confidence (DC), visual assessment of contrast enhancement (VCE) and CNRlesion/parenchyma were assessed for each lesion. RESULTS: Significantly more lesions were detected with T1-mVISTA compared to the MP-RAGE (61 vs. 36; p < 0.05). Further, DC and VCE was rated significantly higher in the T1-mVISTA (p < 0.05 and p < 0.001). Mean CNRlesion/parenchyma was twofold higher for T1-mVISTA (24.2 ± 17.5 vs. 12.7 ± 11.5, p < 0.001). The 25 lesions detected only in T1-mVISTA were significantly smaller than those detected in both sequences (4.3 ± 3.7 mm vs. 11.3 ± 10.7 mm; p < 0.01). CONCLUSIONS: T1-mVISTA increases the contrast of lesions significantly compared to MP-RAGE and might therefore improve detection rates of small lesions in early stages of disease. KEY POINTS: • T1-mVISTA leads to significantly higher contrast-to-noise ratios of cerebral malignomas. • T1-mVISTA detects significantly more metastatic lesions compared to 3D-MPRAGE. • Lesions detected only by T1-mVISTA are smaller than those detected in both sequences. • Diagnostic confidence is significantly higher for lesions detected by T1-mVISTA. • Application of T1-mVISTA might be of high relevance in early stages of disease.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/secundario , Adolescente , Adulto , Anciano , Neoplasias Encefálicas/patología , Niño , Preescolar , Medios de Contraste , Femenino , Compuestos Heterocíclicos , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos , Estudios Retrospectivos , Adulto Joven
2.
Radiologe ; 56(1): 52-69, 2016 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-26754274

RESUMEN

Cerebral vasculitis can have a variety of origins. Furthermore, there are no vasculitis-specific symptoms or imaging signs and vasculitis of the CNS can mimic many other neurological diseases, which require different treatment approaches. Thus, the clinical and radiological diagnosis of cerebral vasculitis is challenging. Magnetic resonance imaging (MRI) and MR angiography (MRA) should be the radiological imaging methods of choice to assess the degree of parenchymal damage and to detect vessel wall changes. If the results are unclear digital subtraction angiography (DSA) should be pursued in order to also detect changes in medium sized vessels. Vasculitis of small vessels cannot be detected by vascular imaging and requires brain or leptomeningeal biopsy. In this review we present the current diagnostic approach and a variety of imaging findings in cerebral vasculitis and discuss the main radiological differential diagnoses.


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Vasculitis del Sistema Nervioso Central/tratamiento farmacológico , Humanos , Posicionamiento del Paciente/métodos
3.
Eur Radiol ; 23(10): 2784-92, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23732685

RESUMEN

OBJECTIVES: To compare the use of an unenhanced high-resolution time-of-flight MR angiography sequence (Hr-TOF MRA) with fat-suppressed axial/coronal T1-weighted images and contrast-enhanced angiography (standard MRI) for the diagnosis of cervical artery dissection (cDISS). METHODS: Twenty consecutive patients (9 women, 11 men, aged 24-66 years) with proven cDISS on standard MRI underwent Hr-TOF MRA at 3.0 T using dedicated surface coils. Sensitivity (SE), specificity (SP), positive and negative predictive values (PPV, NPV), Cohen's kappa (к) and accuracy of Hr-TOF MRA were calculated using the standard protocol as the gold standard. Image quality and diagnostic confidence were assessed on a four-point scale. RESULTS: Image quality was rated better for standard MRI (P = 0.02), whereas diagnostic confidence did not differ significantly (P = 0.27). There was good agreement between Hr-TOF images and the standard protocol for the presence/absence of cDISS, with к = 0.95 for reader 1 and к = 0.89 for reader 2 (P < 0.001). This resulted in SE, SP, PPV, NPV and accuracy of 97 %, 98 %, 97 %, 98 % and 97 % for reader 1 and 93 %, 96 %, 93 %, 96 % and 95 % for reader 2. CONCLUSIONS: Hr-TOF MRA can be used to diagnose cDISS with excellent agreement compared with the standard protocol. This might be useful in patients with renal insufficiency or if contrast-enhanced MR angiography is of insufficient image quality. KEY POINTS: • New magnetic resonance angiography sequences are increasingly used for vertebral artery assessment. • A high-resolution time-of-flight sequence allows the diagnosis of cervical artery dissection. • This technique allows the diagnosis without intravenous contrast medium. • It could help in renal insufficiency or when contrast-enhanced MRA fails.


Asunto(s)
Tejido Adiposo/patología , Disección de la Arteria Carótida Interna/patología , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Almacenamiento y Recuperación de la Información/métodos , Imagen por Resonancia Magnética/métodos , Técnica de Sustracción , Adulto , Anciano , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
4.
Scand J Rheumatol ; 42(5): 379-82, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23713482

RESUMEN

OBJECTIVES: The psoriatic arthritis magnetic resonance imaging scoring system (PsAMRIS-H) for the evaluation of inflammatory and destructive changes in PsA hands was validated on 0.6-T scanners. The applicability of the PsAMRIS-H on a low-field MRI system as a well-accepted, low-cost imaging modality was evaluated. METHOD: In 65 consecutive patients (31 males, median age 52 years), 73 scans on a 0.2-T dedicated extremity MRI system were obtained for evaluation of PsA. Images were scored for synovitis, tenosynovitis, periarticular enhancement, bone erosion, bone oedema, and proliferation, and the PsAMRIS-H score was calculated. The intraclass correlation coefficient (ICC) was calculated and the paired t-test conducted. RESULTS: Intra-reader reliability for the total PsAMRIS-H score was good, with an ICC of 0.81 and 0.77 for readers 1 and 2, respectively, and inter-reader agreement was moderate (0.57 for each reader). However, the PsAMRIS-H score differed significantly between the two readers (22 vs. 31; p < 0.05). When individual components of the PsAMRIS were evaluated, intra- and inter-reader agreement was poor to moderate, especially for tenosynovitis and periarticular inflammation. CONCLUSIONS: Low-field 0.2-T MRI is capable of quantifying the PsAMRIS-H with good intra-reader reproducibility. However, low signal-to-noise ratio (SNR), low spatial resolution, and system artefacts limit the application of the PsAMRIS-H, leading to low inter- and intra-reader agreement for individual features.


Asunto(s)
Artritis Psoriásica/patología , Articulaciones de los Dedos/patología , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Edema/patología , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Sinovitis/patología , Tenosinovitis/patología , Adulto Joven
5.
AJNR Am J Neuroradiol ; 42(9): 1566-1575, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34326105

RESUMEN

Current guidelines for primary and secondary prevention of stroke in patients with carotid atherosclerosis are based on the quantification of the degree of stenosis and symptom status. Recent publications have demonstrated that plaque morphology and composition, independent of the degree of stenosis, are important in the risk stratification of carotid atherosclerotic disease. This finding raises the question as to whether current guidelines are adequate or if they should be updated with new evidence, including imaging for plaque phenotyping, risk stratification, and clinical decision-making in addition to the degree of stenosis. To further this discussion, this roadmap consensus article defines the limits of luminal imaging and highlights the current evidence supporting the role of plaque imaging. Furthermore, we identify gaps in current knowledge and suggest steps to generate high-quality evidence, to add relevant information to guidelines currently based on the quantification of stenosis.


Asunto(s)
Enfermedades de las Arterias Carótidas , Estenosis Carotídea , Placa Aterosclerótica , Accidente Cerebrovascular , Arterias Carótidas , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/terapia , Consenso , Humanos , Placa Aterosclerótica/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/prevención & control
6.
BMC Med Imaging ; 10: 27, 2010 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-21118504

RESUMEN

BACKGROUND: Plaque imaging based on magnetic resonance imaging (MRI) represents a new modality for risk assessment in atherosclerosis. It allows classification of carotid plaques in high-risk and low-risk lesion types (I-VIII). Type 2 diabetes mellitus (DM 2) represents a known risk factor for atherosclerosis, but its specific influence on plaque vulnerability is not fully understood. This study investigates whether MRI-plaque imaging can reveal differences in carotid plaque features of diabetic patients compared to nondiabetics. METHODS: 191 patients with moderate to high-grade carotid artery stenosis were enrolled after written informed consent was obtained. Each patient underwent MRI-plaque imaging using a 1.5-T scanner with phased-array carotid coils. The carotid plaques were classified as lesion types I-VIII according to the MRI-modified AHA criteria. For 36 patients histology data was available. RESULTS: Eleven patients were excluded because of insufficient MR-image quality. DM 2 was diagnosed in 51 patients (28.3%). Concordance between histology and MRI-classification was 91.7% (33/36) and showed a Cohen's kappa value of 0.81 with a 95% CI of 0.98-1.15. MRI-defined high-risk lesion types were overrepresented in diabetic patients (n = 29; 56.8%). Multiple logistic regression analysis revealed association between DM 2 and MRI-defined high-risk lesion types (OR 2.59; 95% CI [1.15-5.81]), independent of the degree of stenosis. CONCLUSION: DM 2 seems to represent a predictor for the development of vulnerable carotid plaques irrespective of the degree of stenosis and other risk factors. MRI-plaque imaging represents a new tool for risk stratification of diabetic patients.


Asunto(s)
Estenosis Carotídea/diagnóstico , Estenosis Carotídea/epidemiología , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Imagen por Resonancia Magnética/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Factores de Riesgo , Sensibilidad y Especificidad
7.
Nuklearmedizin ; 49(4): 148-53, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20532464

RESUMEN

AIM: Fluorine-labelled choline derivatives were recently suggested as agents for visualizing vulnerable atherosclerotic plaques. We therefore aimed to evaluate the association between18F-fluoroethylcholine (FEC) uptake in the wall of large arteries, where calcification was also measured, with the presence of cardiovascular risk factors and occurrence of prior cardiovascular events. PATIENTS, METHODS: Detailed clinical information, including common cardiovascular risk factors, was obtained retrospectively in 60 prostate cancer patients examined with whole-body FEC PET-CT. In each patient, we calculated the mean blood pool-corrected SUV, as well as the mean target-to-background ratio (TBR), in addition to the sum of calcified plaques (CPsum) from six major vessels: ascending and descending aorta, aortic arch, abdominal aorta, and both iliac arteries. RESULTS: As reported previously, the CPsum correlated significantly with cardiovascular risk factors, in contrast to mean SUV or TBR scores, which did not show any significance with the presence of cardiovascular risk factors. There was no correlation between CPsum, mean TBR or SUV, nor was there any significant association of CPsum, mean TBR or SUV with the prior occurrence of cardio- or cerebrovascular events. CONCLUSION: Contrary to a recent report, we found in our rather large cohort of elderly prostate cancer patients no significant association between FEC uptake in large vessels and atherosclerotic plaque burden, or the presence of cardiovascular risk factors. In line with prior reports on structural changes in vessels, increased calcified atherosclerotic plaque burden was strongly associated with the occurrence of common cardiovascular risk factors.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Colina/análogos & derivados , Radioisótopos de Flúor , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Calcinosis/diagnóstico por imagen , Enfermedades Cardiovasculares/diagnóstico por imagen , Colina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
8.
Radiologe ; 50(10): 861-71, 2010 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-20799025

RESUMEN

Vasculitis is a rare disease and clinical symptoms are often unspecific. Accurate and early diagnosis is mandatory in order to prevent complications, such as loss of vision or stroke. Imaging techniques can contribute to establishing a definite diagnosis and to evaluate disease activity and the extent of the disease in various vascular regions. Conventional imaging methods, such as computed tomography (CT) and magnetic resonance (MR) angiography, as well as digital subtraction angiography allow the vessel lumen but not the vessel wall to be depicted. However, vasculitis is a disease which primarily affects the vessel wall, therefore conventional imaging modalities often fail to make a definite diagnosis. Recently black-blood high resolution MR in vivo imaging has been used to visualize cervical and intracranial vasculitis. This review article presents imaging protocols for intracranial and cervical black-blood MR imaging and clinical cases with large vessel vasculitis and vasculitis of the central nervous system. Furthermore the current literature, examples of the most common differential diagnoses of cervical and cranial arteriopathy and the potential of other imaging modalities, such as PET/CT and ultrasound will be discussed.


Asunto(s)
Angiografía de Substracción Digital , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Angiografía por Resonancia Magnética/métodos , Tomografía de Emisión de Positrones , Vasculitis Sistémica/diagnóstico , Tomografía Computarizada por Rayos X , Vasculitis del Sistema Nervioso Central/diagnóstico , Adulto , Anciano , Enfermedades de la Aorta/diagnóstico , Enfermedades de la Aorta/patología , Arteriopatías Oclusivas/diagnóstico , Arteriopatías Oclusivas/patología , Arterias/patología , Enfermedades Autoinmunes/diagnóstico , Enfermedades Autoinmunes/patología , Femenino , Arteritis de Células Gigantes/diagnóstico , Arteritis de Células Gigantes/patología , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Vasculitis Sistémica/patología , Arteritis de Takayasu/diagnóstico , Arteritis de Takayasu/patología , Vasculitis del Sistema Nervioso Central/patología , Adulto Joven
9.
Radiologe ; 50(4): 355-65, 2010 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-20221580

RESUMEN

Atherosclerosis is a chronic inflammatory disease of middle sized and large vessels with sequelae comprising the most frequent causes of death in the Western world. Modern imaging modalities are being introduced for the study of atherosclerosis with emphasis on the detection of vulnerable plaques. The hybrid imaging method PET/CT presents advantages for the localization of vulnerable plaques based on the uptake of various molecular imaging agents indicative of inflammatory processes. Using semiquantitative image analysis fluorodeoxyglucose (FDG) uptake in large peripheral vessels has been identified in a series of 21 patients, who were scanned first with the previous generation of PET/CT scanner and subsequently with a new generation apparatus, after a mean interval of 6.5 months. The mean ratio of FDG uptake in the walls of eight large vessels to the blood-pool activity (TBR) was nearly identical in the two PET/CT sessions (TBR(1) 1.26 versus TBR(2) 1.28; p=n.s.), indicating independence of the TBR endpoint from the particular instrumentation.


Asunto(s)
Aterosclerosis/diagnóstico , Aterosclerosis/metabolismo , Fluorodesoxiglucosa F18/farmacocinética , Tomografía de Emisión de Positrones/métodos , Técnica de Sustracción , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Rofo ; 180(6): 553-60, 2008 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-18504666

RESUMEN

PURPOSE: To prospectively evaluate whether planimetric measurements of aortic valve area (AVA) with dual-source computed tomography (DSCT) correlate with measurements obtained by echocardiography and to correlate the amount of calcification of the aortic valve with AVA in a group of patients after aortic valve replacement. MATERIALS AND METHOD: 23 patients underwent dual-source computed tomography (DSCT) of the heart (Somatom Definition, Siemens Medical Solutions, Forchheim, Germany), without heart rate control (heart rate 52-113 beats/minute). All patients had undergone aortic valve replacement (homografts, mean time after surgery: 7+/-3 years). The AVA of the transplanted aortic valve graft was measured planimetrically by means of DSCT and compared with echocardiography as a standard of reference, to exclude post-surgical restenosis of the valve. Maximum AVA in systole planimetrically measured with CT was compared with calculated AVA values determined with the continuity equation, using transvalvular pressure gradients. The amount of calcification of the aortic valve was quantified and correlated (Spearman's R) with the AVA. To assess intra- and inter-reader reproducibility, the DCST data was re-analyzed by two readers 4 weeks after the initial review. RESULTS: All DSCT datasets were of diagnostic image quality concerning valve depiction. The mean AVA as measured by DSCT was 2.7+/-0.9 cm (2) compared to 1.8+/-0.5 cm (2) by echocardiography (p<0.05). The planimetric evaluation of the CT data as compared to results of echocardiography showed a significant correlation of the results (Pearson's correlation coefficient R=0.78, p<0.001). Intra- and inter-reader reproducibility was good with intra-class correlation coefficients of 0.86 and 0.81, respectively (p<0.001). There was a significant negative correlation between the amount of aortic valve calcification and AVA as measured by echocardiography (R= -0.42; p<0.05) and as measured by DSCT (R= -0.67; p=0.001). CONCLUSION: First experience indicates that DSCT is able to assess aortic valve opening area with high image quality and good intra- and inter-reader reproducibility in subjects after aortic valve replacement. The negative correlation between AVA and the amount of aortic valve calcification suggests that calcification is a possible risk factor for restenosis in subjects with aortic valve replacement.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico , Bioprótesis , Calcinosis/diagnóstico , Ecocardiografía/métodos , Análisis de Falla de Equipo/métodos , Prótesis Valvulares Cardíacas , Procesamiento de Imagen Asistido por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Estenosis de la Válvula Aórtica/fisiopatología , Calcinosis/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Sensibilidad y Especificidad
11.
Rofo ; 180(2): 100-11, 2008 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-18058634

RESUMEN

Stroke is the third most common cause of mortality in the United States with an incidence rate of approximately 700 000 deaths per year. As a means to prevent cerebrovascular events, current concepts advocate endarterectomy or carotid stenting in patients with advanced carotid disease. Arterial stenosis alone has been shown to be a poor predictor of cardiovascular events and therefore both arterial stenosis and patient symptom status are taken as indications for interventional therapy. Several studies have shown that symptomatic subjects benefit more from a carotid endarterectomy than asymptomatic subjects: 3-6 carotid endarterectomies are needed to prevent one stroke per year in symptomatic subjects with > 70 % stenosis compared to 14 - 17 carotid endarterectomies in asymptomatic patients with > 50 % stenosis. It is commonly accepted today that factors other than the degree of luminal stenosis can determine a patient's symptom status, such as the composition or the superficial structure of atherosclerotic plaque. High-resolution magnetic resonance imaging has overcome the limitations of current angiographic techniques and has emerged as a leading non-invasive imaging modality for atherosclerotic disease, especially within carotid arteries and other large vessels. In this review, the state of the art in MRI of atherosclerosis is presented in terms of hardware and image acquisition protocols. Also, the results of validation studies for measuring lesion size, composition and inflammation will be summarized. Finally, the status of several clinical trials involving MRI of atherosclerosis will be reviewed.


Asunto(s)
Arterias Carótidas/patología , Enfermedades de las Arterias Carótidas/diagnóstico , Aumento de la Imagen/instrumentación , Aumento de la Imagen/métodos , Angiografía por Resonancia Magnética/instrumentación , Angiografía por Resonancia Magnética/métodos , Diseño de Equipo , Humanos , Angiografía por Resonancia Magnética/tendencias
12.
AJNR Am J Neuroradiol ; 39(2): E9-E31, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29326139

RESUMEN

Identification of carotid artery atherosclerosis is conventionally based on measurements of luminal stenosis and surface irregularities using in vivo imaging techniques including sonography, CT and MR angiography, and digital subtraction angiography. However, histopathologic studies demonstrate considerable differences between plaques with identical degrees of stenosis and indicate that certain plaque features are associated with increased risk for ischemic events. The ability to look beyond the lumen using highly developed vessel wall imaging methods to identify plaque vulnerable to disruption has prompted an active debate as to whether a paradigm shift is needed to move away from relying on measurements of luminal stenosis for gauging the risk of ischemic injury. Further evaluation in randomized clinical trials will help to better define the exact role of plaque imaging in clinical decision-making. However, current carotid vessel wall imaging techniques can be informative. The goal of this article is to present the perspective of the ASNR Vessel Wall Imaging Study Group as it relates to the current status of arterial wall imaging in carotid artery disease.


Asunto(s)
Arterias Carótidas/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Túnica Íntima/diagnóstico por imagen , Túnica Media/diagnóstico por imagen , Anciano , Angiografía de Substracción Digital , Aterosclerosis/patología , Arterias Carótidas/patología , Estenosis Carotídea/patología , Consenso , Humanos , Masculino , Túnica Íntima/patología , Túnica Media/patología , Ultrasonografía , Estados Unidos
14.
Arterioscler Thromb Vasc Biol ; 25(1): 234-9, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15528475

RESUMEN

OBJECTIVE: This study evaluates the ability of MRI to quantify all major carotid atherosclerotic plaque components in vivo. METHODS AND RESULTS: Thirty-one subjects scheduled for carotid endarterectomy were imaged with a 1.5T scanner using time-of-flight-, T1-, proton density-, and T2-weighted images. A total of 214 MR imaging locations were matched to corresponding histology sections. For MRI and histology, area measurements of the major plaque components such as lipid-rich/necrotic core (LR/NC), calcification, loose matrix, and dense (fibrous) tissue were recorded as percentages of the total wall area. Intraclass correlation coefficients (ICCs) were computed to determine intrareader and inter-reader reproducibility. MRI measurements of plaque composition were statistically equivalent to those of histology for the LR/NC (23.7 versus 20.3%; P=0.1), loose matrix (5.1 versus 6.3%; P=0.1), and dense (fibrous) tissue (66.3% versus 64%; P=0.4). Calcification differed significantly when measured as a percentage of wall area (9.4 versus 5%; P<0.001). Intrareader and inter-reader reproducibility was good to excellent for all tissue components, with ICCs ranging from 0.73 to 0.95. CONCLUSIONS: MRI-based tissue quantification is accurate and reproducible. This application can be used in therapeutic clinical trials and in prospective longitudinal studies to examine carotid atherosclerotic plaque progression and regression.


Asunto(s)
Enfermedades de las Arterias Carótidas/patología , Imagen por Resonancia Magnética/métodos , Anciano , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Arterioscler Thromb Vasc Biol ; 25(3): 611-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15653565

RESUMEN

OBJECTIVE: Ethnicity-based research may identify new clues to the pathogenesis of atherosclerotic disease. Therefore, we sought to determine whether carotid lesions differ between 20 Chinese and 20 Caucasian Americans by MRI. METHODS AND RESULTS: Inclusion criteria were >50% stenosis as measured by duplex ultrasound and recent symptoms attributed to carotid artery disease. The patients were imaged in 2 centers (Beijing, China and Seattle, Wash) using a standardized protocol. Both carotid arteries were reviewed quantitatively (lumen, wall, outer wall, tissue components) and morphologically (lesion types, fibrous cap status). Significant differences between the Chinese and Americans were found for the mean size of the lipid/necrotic core (13.6 versus 7.8 mm2; P=0.002), percentage of slices with calcified type VII lesions (1.6 versus 12.4%; P=0.03), and percentage of slices with early type III lesions (19.3 versus 9.3%; P=0.02). Furthermore, the mean outer wall area in the common carotid artery was larger in the Chinese population (P=0.007). CONCLUSIONS: This pilot study suggests that composition and morphology of atherosclerotic lesions in symptomatic carotid disease differ between ethno-racial groups. Quantitative MRI-based review of carotid atherosclerosis comparing plaque morphology and composition between ethno-racial groups is feasible, and future MRI studies may improve our understanding of the pathophysiology of this disease.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Enfermedades de las Arterias Carótidas/etnología , Enfermedades de las Arterias Carótidas/patología , Imagen por Resonancia Magnética , Población Blanca/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Arteria Carótida Común/patología , China/epidemiología , Femenino , Humanos , Imagen por Resonancia Magnética/normas , Masculino , Persona de Mediana Edad , Fantasmas de Imagen , Proyectos Piloto , Reproducibilidad de los Resultados , Factores de Riesgo , Estados Unidos/epidemiología
16.
Circulation ; 110(20): 3239-44, 2004 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-15533871

RESUMEN

BACKGROUND: Intraplaque hemorrhage and juxtaluminal hemorrhage/thrombus may differ in cause and clinical implications. This study tested the hypothesis that MRI can distinguish between intraplaque hemorrhage and juxtaluminal hemorrhage/thrombus and investigated the association between hemorrhage and underlying lesion types. METHODS AND RESULTS: Twenty-six patients scheduled for carotid endarterectomy were imaged with a 1.5-T GE scanner by a multicontrast-weighted MRI technique. Hemorrhages were identified with previously established MRI criteria, and differentiations were made between intraplaque and juxtaluminal hemorrhage/thrombus. Corresponding histology was used to confirm the magnetic resonance findings. Tissues underlying areas of hemorrhage/thrombus were histologically categorized according to modified American Heart Association criteria. Of 190 matched sections, 140 contained areas of hemorrhage by histology, of which MRI correctly detected 134. The sensitivity and specificity for MRI to correctly identify cross sections that contained hemorrhage were 96% and 82%, respectively. Furthermore, MRI was able to distinguish juxtaluminal hemorrhage/thrombus from intraplaque hemorrhage with an accuracy of 96%. The distribution of lesion types underlying hemorrhages differed significantly (P=0.004). Intraplaque hemorrhage had an underlying lipid-rich type IV/V lesion in 55% of histological sections, whereas juxtaluminal hemorrhage/thrombus had an underlying calcified lesion type VII in 70% of sections. CONCLUSIONS: In vivo high-resolution MRI can detect and differentiate intraplaque hemorrhage from juxtaluminal hemorrhage/thrombus with good accuracy. The association of hemorrhage and lesion types suggests potential differences in origin. Noninvasive MRI therefore provides a possible tool for prospectively studying differences in origin of plaque hemorrhage and the association of plaque progression and instability.


Asunto(s)
Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/patología , Trombosis de las Arterias Carótidas/patología , Hemorragia/patología , Imagen por Resonancia Magnética/métodos , Enfermedades de las Arterias Carótidas/etiología , Enfermedades de las Arterias Carótidas/cirugía , Trombosis de las Arterias Carótidas/etiología , Endarterectomía Carotidea , Hemorragia/clasificación , Hemorragia/etiología , Humanos , Especificidad de Órganos , Sensibilidad y Especificidad
17.
Rofo ; 177(9): 1250-4, 2005 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-16123871

RESUMEN

PURPOSE: To evaluate the prevalence of latent and manifest hyperthyroidism in a non-selected group of patients admitted for contrast enhanced CT studies blood samples were tested for the levels of thyroid-stimulating hormone (TSH). MATERIAL AND METHODS: TSH blood levels were obtained in 548 consecutive patients who were scheduled for contrast-enhanced (Iopromide; 300 mg iodine/ml) CT scanning. In case of TSH levels < 0.4 mU/l, blood samples were also tested for triiodothyronine (T3) and tetraiodothyronine (T4) blood levels, and treatment with Irenat (sodium perchlorate) was commenced before scanning. In case of TSH levels < 0.1 mU/l, CT scanning was not performed but further evaluation of the thyroid function was initiated. RESULTS: TSH blood levels ranged from 0.4 to 7.5 mU/l in 512 patients, and 36 patients (6.6%) had TSH blood levels < 0.4 mU/l and 9 patients blood levels < 0.1 mU/l, with 32 of those patients (5.8%) having regular T3 and T4 blood levels consistent with latent hyperthyroidism. In 4 patients (0.8%), T3 or T4 blood levels were increased consistent with manifest hyperthyroidism. CONCLUSION: In South Germany, the prevalence of latent or manifest hyperthyroidism in a non-selected patient group is high. Therefore TSH blood levels should be obtained prior to contrast-enhanced CT studies.


Asunto(s)
Medios de Contraste , Hipertiroidismo/epidemiología , Yohexol/análogos & derivados , Tirotropina/sangre , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Alemania/epidemiología , Humanos , Hipertiroidismo/sangre , Persona de Mediana Edad , Percloratos/administración & dosificación , Prevalencia , Compuestos de Sodio/administración & dosificación , Tiroxina/sangre , Triyodotironina/sangre
18.
Handchir Mikrochir Plast Chir ; 47(3): 175-81, 2015 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-26084857

RESUMEN

AIM: Therapy of scapholunate advanced collapse (SLAC) wrist should be guided by the degree of arthritic changes within the radioscaphoid and midcarpal joints (stage 1-3 after Watson). Diagnostic investigations usually include X-ray imaging and wrist arthoscopy. In the present study, the interrater reliability of SLAC wrist stage classification by means of X-ray image analysis was evaluated between radiologists and hand surgeons. Ultimately, the influence of diagnostic wrist arthroscopy on the final stage classification was determined. PATIENTS AND METHODS: Retrospectively, 38 SLAC wrists of 37 patients were included in this study. Conventional X-ray images in a dorso-palmar and lateral view were performed before diagnostic wrist arthroscopy. The degree of carpal collapse on X-rays was determined by 2 radiologists and 2 surgeons (1 board certified hand surgeon, 1 plastic surgeon, both experienced in hand surgery since years). After 14 days the stages were re-evaluated by the surgeons with the digital images from the wrist arthroscopies at hand. RESULTS: While the interrater reliability turned out to be 'weak' amidst the radiologists, it was classified as 'light' among the surgeons. We found a 'weak' and a 'light' interrater reliability between the surgeons and the radiologists. Radiologists tended to assess the degree of severity higher than surgeons. The additional knowledge of the digital arthroscopy images led to a different classification in 55%. When X-rays were assessed in combination with the arthroscopy findings, both stage 1 and stage 3 were diagnosed less frequently. CONCLUSIONS: Our study suggests that interpreting X-ray films alone is an unreliable method to assess the stage of SLAC wrist. We believe that additional diagnostic measures such as wrist arthroscopy are needed to accurately diagnose the SLAC wrist stage.


Asunto(s)
Artroscopía , Evaluación de la Discapacidad , Luxaciones Articulares/clasificación , Luxaciones Articulares/diagnóstico , Ligamentos Articulares/lesiones , Hueso Semilunar/lesiones , Osteoartritis/clasificación , Osteoartritis/diagnóstico , Hueso Escafoides/lesiones , Adulto , Anciano , Conducta Cooperativa , Femenino , Humanos , Comunicación Interdisciplinaria , Hueso Semilunar/cirugía , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Retrospectivos , Rotura , Hueso Escafoides/cirugía
19.
Rofo ; 176(9): 1302-10, 2004 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-15346266

RESUMEN

PURPOSE: To evaluate whether stent placement is superior to percutaneous transluminal angioplasty (PTA) in the treatment of chronic symptoms in short femoropopliteal arterial stenoses. MATERIALS AND METHODS: One hundred twenty-four limbs in 116 patients, who ranged in age from 39 to 87 years (mean age, 67 years), were randomized to PTA (n = 53) versus PTA followed by implantation of long-medium Palmaz-Stents (n = 71). Inclusion criteria were intermittent claudication or chronic critical limb ischemia, short stenosis or occlusion (lesion length < or = 5 cm), and at least one patent run-off vessel at angiography. The follow-up included clinical assessment, measurement of ankle/brachial index (ABI), color duplex ultrasound, and/or angiography at 6, 12 and 24 months. Angiographic follow-up between 12 and 36 months was available in 54 limbs (45 %). RESULTS: Initial technical success was achieved in 50 of 53 limbs (94.4 %) in the PTA group versus 70 of 71 limbs (98.6 %) in the stent group. Overall, major complications occurred in 9.5 % (n = 11), with n = 4 in the PTA group compared to n = 7 in the stent group. No difference was found between the groups of treatment: clinical success at 1 and 2 years was 80.5 and 77.1 % in the PTA group versus 78.1 and 71.0 % in the stent group. The cumulative 1-year and 2-year angiographic primary patency rates were 66.1 and 49.1 % in the stent group versus 76.1 and 66.1 % in the PTA group. The secondary 1-year and 2-year angiographic patency rates were 88.5 and 53.3 % in the stent group versus 82.7 % and 76.2 % in the PTA group. CONCLUSION: The primary success rate was slightly higher after stent placement than after PTA. However, the angiographic, clinical and hemodynamic success after 1 and 2 years tends to be slightly better for PTA.


Asunto(s)
Angioplastia de Balón , Arteriopatías Oclusivas/terapia , Arteria Femoral , Arteria Poplítea , Stents , Adulto , Anciano , Anciano de 80 o más Años , Angiografía , Angioplastia de Balón/efectos adversos , Interpretación Estadística de Datos , Femenino , Arteria Femoral/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Arteria Poplítea/diagnóstico por imagen , Estudios Prospectivos , Stents/efectos adversos , Factores de Tiempo , Ultrasonografía Doppler en Color , Grado de Desobstrucción Vascular
20.
AJNR Am J Neuroradiol ; 34(12): 2331-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23868157

RESUMEN

BACKGROUND AND PURPOSE: High-resolution carotid MR imaging can accurately identify complicated American Heart Association lesion type VI plaques, which are characterized by thrombus, hemorrhage, or a ruptured fibrous cap. The purpose of this study is to evaluate whether CTA can be used as screening tool to predict the presence or absence of American Heart Association lesion type VI plaques as defined by high-resolution MR imaging. METHODS: Fifty-one patients with suspected ischemic stroke or TIA with carotid CTA and carotid MR imaging performed within 14 days of the event/admission from April 2008 to December 2010 were reviewed. Vessels with stents or occlusion were excluded (n = 2). Each carotid artery was assigned an American Heart Association lesion type classification by MR imaging. The maximum wall thickness, maximum soft plaque component thickness, maximum calcified component thickness, and its attenuation (if the soft plaque component thickness was >2 mm) were obtained from the CTA. RESULTS: The maximum soft plaque component thickness proved the best discriminating factor to predict a complicated plaque by MR imaging, with a receiver operating characteristic area under the curve of 0.89. The optimal sensitivity and specificity for detection of complicated plaque by MR imaging was achieved with a soft plaque component thickness threshold of 4.4 mm (sensitivity, 0.65; specificity, 0.94; positive predictive value, 0.75; and negative predictive value, 0.9). No complicated plaque had a soft tissue plaque thickness <2.2 mm (negative predictive value, 1) and no simple (noncomplicated) plaque had a thickness >5.6 mm (positive predictive value, 1). CONCLUSIONS: Maximum soft plaque component thickness as measured by carotid CTA is a reliable indicator of a complicated plaque, with a threshold of 2.2 mm representing little to no probability of a complicated American Heart Association lesion type VI plaque.


Asunto(s)
Algoritmos , Angiografía/métodos , Estenosis Carotídea/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Tamizaje Masivo/métodos , Anciano , Grosor Intima-Media Carotídeo , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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