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2.
Arq. neuropsiquiatr ; 78(10): 642-650, Oct. 2020. tab, graf
Article in English | LILACS | ID: biblio-1131688

ABSTRACT

ABSTRACT Intracranial vessel wall imaging plays an increasing role in diagnosing intracranial vascular diseases. With the growing demand and subsequent increased use of this technique in clinical practice, radiologists and neurologists should be aware of the choices in imaging parameters and how they affect image quality, clinical indications, methods of assessment, and limitations in the interpretation of these images. Due to the improvement of the MRI techniques, the possibility of accurate and direct evaluation of the abnormalities in the arterial vascular wall (vessel wall imaging) has evolved, adding substantial data to diagnosis when compared to the indirect evaluation based on conventional flow analyses. Herein, the authors proposed a comprehensive approach of this technique reinforcing appropriated clinical settings to better use intracranial vessel wall imaging.


RESUMO O estudo angiográfico intracraniano não invasivo está sendo amplamente utilizado no diagnóstico de doenças vasculares intracranianas. Com a crescente demanda e o aumento subsequente do uso dessa técnica na prática clínica, radiologistas e neurologistas devem estar cientes das opções nos parâmetros de imagem e como estes afetam a qualidade da imagem, as indicações clínicas, os métodos de avaliação e as limitações na interpretação dessas imagens. Devido ao aprimoramento das técnicas de imagem por RM, a possibilidade de avaliação precisa e direta das anormalidades na parede vascular arterial (vessel wall imaging) evoluiu, agregando dados substanciais ao diagnóstico quando comparados à avaliação indireta baseada em análises de fluxo convencionais. Neste artigo, os autores discorrem sobre a avaliação e interpretação dos achados de imagem desta nova técnica e suas aplicações clínicas.


Subject(s)
Humans , Magnetic Resonance Imaging , Cerebrovascular Disorders , Magnetic Resonance Angiography/methods , Head
3.
Medicina (B.Aires) ; 80(1): 84-86, feb. 2020. ilus
Article in Spanish | LILACS | ID: biblio-1125041

ABSTRACT

El síndrome de Klippel-Trenaunay-Weber (SKTW) es una rara malformación venosa que, en general afecta a los miembros inferiores y, más raramente, a los superiores. Se caracteriza por formaciones angiomatosas cutáneas, várices e hipertrofia del miembro afectado. El compromiso genitourinario es sumamente infrecuente. Se presenta el caso de una paciente de 14 años. Ingresó por hematuria macroscópica de 48 h de evolución y metrorragia con grave compromiso hemodinámico. Se encontraba en estudio por presentar un hemangioma en el miembro inferior izquierdo que se extendía hasta la región pelviana. La uretrocistofibroscopía demostró la presencia de múltiples lesiones angiomatosas diseminadas en forma amplia en la vejiga, algunas de ellas con sangrado activo. La angioresonancia mostró una voluminosa formación hipervascularizada en contacto con la pared vesical a la cual desplazaba y fístulas arteriovenosas a nivel pelviano y en el miembro inferior izquierdo confirmando el diagnóstico etiológico. Se realizó una embolización arterial selectiva de los territorios ilíacos interno y externo e inmediatamente después una endocoagulación láser de los focos angiomatosos sangrantes. La hematuria remitió completamente en las 24 h posteriores al procedimiento. La metrorragia asociada al SKTW fue controlada mediante la utilización de análogos LHRH y progestágenos.


Klippel-Trenaunay-Weber syndrome (KTWS) is a rare venous malformation that generally affects the lower limbs and, more infrequently, the upper limbs. It is characterized by cutaneous angiomatous formations, varicose veins and hypertrophy of the affected limb. The involvement of the genitourinary tract is extremely infrequent. We expose the case of a 14 years old female patient who was admitted for macroscopic hematuria of 48 hours of evolution and metrorrhagia with severe hemodynamic decompensation. The patient was under study for presenting a hemangioma in the lower left limb that extended to the pelvic region. Urethrocystofibroscopy showed the presence of multiple wide-spread angiomatous lesions in the bladder, some of them with active bleeding. The angio-resonance showed a voluminous hypervascular formation in contact with the bladder wall showing several arteriovenous fistulas at the pelvic level and in the left lower limb confirming the etiological diagnosis. A selective arterial embolization of the internal and external iliac territories was performed and then, a laser endocoagulation of the bleeding angiomatous foci was carried out. The hematuria completely stopped within 24 hours later of the procedure. The metrorrhagia associated with KTWS was controlled by the use of LHRH analogs and progestogens.


Subject(s)
Humans , Female , Adolescent , Klippel-Trenaunay-Weber Syndrome/surgery , Endovascular Procedures/methods , Metrorrhagia/surgery , Pelvis , Klippel-Trenaunay-Weber Syndrome/pathology , Klippel-Trenaunay-Weber Syndrome/diagnostic imaging , Magnetic Resonance Angiography/methods , Gallbladder Diseases/surgery , Gallbladder Diseases/pathology , Hemangioma/surgery , Hemangioma/pathology , Hematuria/surgery , Hematuria/pathology , Metrorrhagia/pathology
6.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 29(3 Supl): 291-296, jul.-set. 2019. tab, graf
Article in English, Portuguese | LILACS | ID: biblio-1023081

ABSTRACT

Avaliar a eficácia diagnóstica da angiotomografia coronariana (AC) comparada com a cineangiocoronariografia (CAT). Material e Métodos: Foram avaliados retrospectivamente 146 pacientes submetidos a AC e CAT com angiografia coronariana quantitativa (ACQ), com intervalo médio de um mês entre os exames. O estudo foi realizado no Hospital Cardiológico Costantini. Foram avaliados os fatores de risco da amostra, a localização das lesões e o grau de severidade da obstrução coronariana nos grandes vasos (TCE, DA, CX e CD). Os resultados dos métodos diagnósticos foram comparados pelo coeficiente de correlação de Pearson. A partir dos achados positivos foi realizada a avaliação de correlação entre os métodos perante a severidade das lesões. Resultados: A amostra foi composta predominantemente por homens (73,97%), sendo a hipertensão arterial (HAS) (71,91%) o fator de risco mais frequente. A artéria mais acometida foi a DA. Quanto ao grau de severidade das lesões, os resultados foram os seguintes na comparação entre AC e CAT: lesões discretas com correlação r = 0,23; moderadas com r = 0,53 e severas com r = 0,70. Na comparação entre AC e ACQ: lesões discretas com correlação r = 0,45; moderadas com r = 0,70 e severas com r = 0,67. Conclusão: A AC apresentou moderada com ACQ e CAT em lesões moderadas e severas, e forte correlação na ausência de lesões quando comparada com ACQ


To evaluate the diagnostic efficacy of multislice CT coronary angiotomography compared with coronary cineangiography. Material and Methods: We retrospectively evaluated 146 patients submitted to MSCT and CA with quantitative coronary angiography (QCA), with a mean interval of one month between the exams. The study was carried out at the Costantini Cardiology Hospital. The risk factors for the sample, the location of the lesions and the degree of severity of the coronary obstruction in the large vessels (LCT, AD, CX and RC).The results of the diagnostic methods were compared using Pearson correlation coefficient. From the positive findings, a correlation evaluation was performed between the methods for the severity of the lesions. Results: The sample consisted predominantly of men (73.97%), and hypertension (SAH) (71.91%) was the most frequent risk factor. The most affected artery was AD. Regarding the degree of severity of the lesions, the results were as follows in the comparison between MSCT and CA: mild lesions with correlation r = 0.23, moderate with r = 0.53 and severe with r = 0.70. In the comparison between MSCT and QCA: mild lesions with correlation r = 0.45, moderate with r = 0.70 and severe with r = 0.67. Conclusion: MSCT showed moderate correlation with QCA and CA in moderate and severe lesions, and a strong correlation in the absence of lesions when compared with QCA


Subject(s)
Humans , Male , Female , Coronary Artery Disease/diagnostic imaging , Angiography/methods , Angiography, Digital Subtraction/methods , Coronary Angiography/methods , Diagnostic Imaging/methods , Cardiovascular Diseases/mortality , Retrospective Studies , Risk Factors , Magnetic Resonance Angiography/methods , Computed Tomography Angiography/methods , Hypertension
7.
Rev. cuba. pediatr ; 91(2): e358, abr.-jun. 2019. graf
Article in Spanish | LILACS, CUMED | ID: biblio-1003962

ABSTRACT

Introducción: La malformación aneurismática de la vena de Galeno es una infrecuente variedad de fístula arteriovenosa cerebral de origen embriológico. Se localiza en la línea media de la fisura coroidal y tiene morfología de amplio espectro. Objetivo: Exponer información actualizada acerca del tema. Método: La información se obtuvo de la búsqueda automatizada realizada fundamentalmente en bases de datos MEDLINE, Current Contents y Scielo. Resultados: La malformación aneurismática de la vena Galeno se manifiesta con síntomas y signos derivados de la insuficiencia cardiaca severa refractaria al tratamiento médico y del daño neurológico que provoca. La entidad implica morbilidad grave y mortalidad en el periodo neonatal. La angiorresonancia es la técnica de referencia, pero la ecografía doppler es buen método de valoración. El tratamiento de elección es la embolización endovascular. Consideraciones finales: Debe existir índice elevado de sospecha para no fracasar en el diagnóstico precoz de la enfermedad. Es importante definir la anatomía de la lesión, por las implicaciones clínicas, terapéuticas y pronósticas que ello acarrea. El tratamiento exitoso sigue siendo un reto terapéutico complejo(AU)


Introduction: Vein of Galen aneurysm is a rare and congenital cerebral arteriovenous abnormality with reported incidence of 1:25 000 live births. It represents the 30 percent of the vascular congenital cerebral malformations that harm the pediatric population. Objective: To show updated information about the topic. Method: The information was obtained from the automated search mostly done in MEDLINE, CurrentContents and Scielo databases. Development: Vein of Galen malformation presents with symptoms and signs derived from the severe refractary heart failure to medical treatment and the neurologic damage it causes. That entity implies severe morbidity and mortality on the neonatal period. Angioresonance is the reference technique, but the Doppler ecography is a good valuation method. The election treatment is the endovascular embolization. Final considerations: There must be an elevated rate of suspect to do not fail on the early diagnostic of the disease. It is important to define the lesion's anatomy, because of the clinic, therapeutic and prognostic implications this represent. The successful treatment is still a complex therapeutic challenge(AU)


Subject(s)
Humans , Male , Female , Ultrasonography, Doppler/methods , Embolization, Therapeutic/methods , Vein of Galen Malformations/epidemiology , Vein of Galen Malformations/diagnostic imaging , Magnetic Resonance Angiography/methods
9.
Rev. chil. neurocir ; 42(2): 151-155, nov. 2016. ilus
Article in Spanish | LILACS | ID: biblio-869768

ABSTRACT

Las lesiones intracraneales penetrantes trans-orbitarias representan pocos casos de todos los Traumas Craneo-encefálicos, sin embargo, representan del 25 al 50 por ciento de todos los traumas penetrantes craneales. Este tipo de traumas trans-orbitarios se han reportado por diferentes tipos de objetos, incluyendo objetos de metal y de madera. Muchos de estos traumas intracraneales pueden pasar desapercibidos en casos donde el material que ingresa no queda expuesto posterior al trauma y cuando no se presenta lesión neurológica que requiera examinación exhaustiva adicional con neuro-imágenes.


Trans-orbital penetrating intracranial injuries represent few cases of all Traumatic Brain Injuries, although they represent between 25 to 50 percent of all penetrating brain injuries. Trans-orbital intracranial penetrating injuries have been reported caused by different types of objects, including metal and wooden objects. Many of these intracranial traumas can be dismissed, especially in those cases where the material is not exposed after the injury and there is no need of further examination with neuroimaging in absence of neurological deficit.


Subject(s)
Humans , Brain Injuries, Traumatic , Brain Injuries, Traumatic/physiopathology , Orbital Fractures , Orbit/anatomy & histology , Orbit/injuries , Head Injuries, Penetrating/diagnosis , Magnetic Resonance Angiography/methods , Foreign Bodies , Tomography, Spiral Computed/methods
10.
ABC., imagem cardiovasc ; 29(4): 136-144, out.-dez. 2016. ilus
Article in Portuguese | LILACS | ID: biblio-834209

ABSTRACT

A ressonância magnética cardíaca (RMC) constitui método não invasivo e tridimensional que permite a avaliaçãomorfológica e funcional de todas as câmaras do coração. Esse método tem ganhado importância na identificaçãoe caracterização de cardiopatias primárias que envolvem o ventrículo direito (VD), além de doenças secundárias que levam à disfunção das câmaras direitas. Dessa forma, este trabalho objetiva elucidar a melhor metodologia no diagnóstico dessas doenças mediante a RMC.


Subject(s)
Humans , Magnetic Resonance Angiography/methods , Ventricular Dysfunction, Right/complications , Ventricular Dysfunction, Right/diagnosis , Arrhythmogenic Right Ventricular Dysplasia/complications , Arrhythmogenic Right Ventricular Dysplasia/diagnosis , Heart Diseases/complications , Heart Diseases/diagnosis , Diagnosis , Echocardiography/methods , Heart , Tricuspid Valve , Heart Ventricles
11.
Rev. cuba. med. gen. integr ; 32(3): 0-0, jul.-set. 2016. ilus
Article in Spanish | LILACS | ID: biblio-960489

ABSTRACT

El Síndrome de Klippel Trenaunay es una malformación vascular congénita caracterizada por una triada de manifestaciones clínicas que comprende una malformación vascular venular, linfática y venosa, junto con hipertrofia esquelética y aumento de tejidos blandos de uno o más miembros. De etiología desconocida, patogénicamente se cree que se produce una alteración en el desarrollo del mesodermo en el feto, que afecta a las líneas angioblástica, linfoblástica y osteoblástica. Se presenta el caso de un paciente femenino de 5 años de edad quien presenta una malformación vascular, diagnosticada inicialmente como hemangioma vascular y posteriormente se asoció a Síndrome de Klippel Trenaunay. El objetivo de la presentación de este caso es generar conocimiento sobre las características clínicas del síndrome de Klippel Trenaunay para un diagnóstico y tratamiento oportuno(AU)


Klippel - Trenaunay -Weber congenital vascular malformation characterized by a triad of clinical manifestations comprising a venular, venous and lymphatic vascular malformation, with hypertrophy increased skeletal and soft tissue of one or more members. Of unknown etiology, it is believed to pathogenically an alteration occurs in mesoderm development in the fetus, which affects angioblastic , and osteoblastic lymphoblastoid lines. Is presentedthe case of a 5 year old that has a vascular malformation, initially diagnosed as vascular hemangioma and later was associated with Klippel- Trenaunay -Weber.Objective: To generate knowledge about the clinical features of KlippelTrenaunay Syndrome for diagnosis and treatment(AU)


Subject(s)
Humans , Female , Child , Propranolol/therapeutic use , Klippel-Trenaunay-Weber Syndrome/diagnosis , Klippel-Trenaunay-Weber Syndrome/etiology , Klippel-Trenaunay-Weber Syndrome/drug therapy , Magnetic Resonance Angiography/methods , Stockings, Compression
12.
Article in English | WPRIM | ID: wpr-222271

ABSTRACT

OBJECTIVE: To determine whether an optimal blood suppression inversion time (BSP TI) can boost arterial visibility and whether the optimal BSP TI is related to breathing rate (BR) and heart rate (HR) for hypertension subjects in spatial labeling with multiple inversion pulses (SLEEK). MATERIALS AND METHODS: This prospective study included 10 volunteers and 93 consecutive hypertension patients who had undergone SLEEK at 1.5T MRI system. Firstly, suitable BSP TIs for displaying clearly renal artery were determined in 10 volunteers. Secondly, non-contrast enhanced magnetic resonance angiography with the suitable BSP TIs were performed on those hypertension patients. Then, renal artery was evaluated and an optimal BSP TI to increase arterial visibility was determined for each patient. Patients' BRs and HRs were recorded and their relationships with the optimal BSP TI were analyzed. RESULTS: The optimal BSP TI was negatively correlated with BR (r1 = -0.536, P1 < 0.001; and r2 = -0.535, P2 < 0.001) and HR (r1 = -0.432, P1 = 0.001; and r2 = -0.419, P2 = 0.001) for 2 readers (kappa = 0.93). For improving renal arterial visibility, BSP TI = 800 ms could be applied as the optimal BSP TI when the 95% confidence interval were 17-19/min (BR1) and 74-82 bpm (HR1) for reader#1 and 17-19/min (BR2) and 74-83 bpm (HR2) for reader#2; BSP TI = 1100 ms while 14-15/min (BR1, 2) and 71-76 bpm (HR1, 2) for both readers; and BSP TI = 1400 ms when 13-16/min (BR1) and 63-68 bpm (HR1) for reader#1 and 14-15/min (BR2) and 64-70 bpm (HR2) for reader#2. CONCLUSION: In SLEEK, BSP TI is affected by patients' BRs and HRs. Adopting the optimal BSP TI based on BR and HR can improve the renal arterial visibility and consequently the working efficiency.


Subject(s)
Adult , Female , Heart Rate , Humans , Hypertension/pathology , Kidney/blood supply , Magnetic Resonance Angiography/methods , Male , Middle Aged , Prospective Studies , Renal Artery/physiology , Respiratory Rate
13.
Salud colect ; 11(1): 49-65, ene.-mar. 2015.
Article in Spanish | LILACS | ID: lil-746684

ABSTRACT

Desde el año 1931 y, especialmente, desde el Código de Núremberg de 1947, un creciente número de declaraciones, regulaciones, normas, guías, leyes, resoluciones y disposiciones pretenden generar condiciones para una mejor protección de los sujetos que participan en estudios de investigación, aunque también algunas implican retrocesos en el respeto a los derechos de poblaciones vulnerables. Sin embargo, todavía no se ha podido evitar la violación de la dignidad de los sujetos de experimentación en ensayos clínicos. Lo que se investiga, cómo se investiga, la calidad y transparencia de los datos obtenidos, el análisis y la publicación de los resultados (tanto de los datos crudos como de los ya elaborados) están sometidos a la lógica del lucro, la cual presenta una tensión permanente con los principios bioéticos y las necesidades de la sociedad. Es necesario el protagonismo activo de los pueblos para que la investigación farmacológica, sus resultados y aplicaciones avancen en un rumbo que subordine el beneficio económico a la protección de los derechos humanos.


Since 1931, and especially since the Nuremberg Code of 1947, an increasing number of declarations, regulations, norms, guidelines, laws, resolutions, and rules intended to create conditions for better protection of subjects participating in research studies have been published, although some have meant setbacks in the human rights of vulnerable populations. As such, violations of the dignity of experimental subjects in clinical trials continue. What researchers investigate and how the research is done, the quality and transparency of the data, and the analysis and the publication of results (of both raw and processed data) respond to the financial interests of the pharmaceutical companies, coming into permanent tension with bioethical principles and the needs of society. The active participation of civil society is necessary to make it so that pharmaceutical research, results and applications subordinate economic benefits to the protection of human rights.


Subject(s)
Adult , Humans , Male , Arrhythmogenic Right Ventricular Dysplasia/diagnosis , Cardiomyopathy, Dilated/diagnosis , Heart Aneurysm/diagnosis , Atrophy/pathology , Edema/pathology , Fibrosis/pathology , Magnetic Resonance Angiography/methods , Myocardium/pathology
14.
Article in English | WPRIM | ID: wpr-183066

ABSTRACT

Coronary artery problems in children usually have a significant impact on both short-term and long-term outcomes. Early and accurate diagnosis, therefore, is crucial but technically challenging due to the small size of the coronary artery, high heart rates, and limited cooperation of children. Coronary artery visibility on CT and MRI in children is considerably improved with recent technical advancements. Consequently, CT and MRI are increasingly used for evaluating various congenital and acquired coronary artery abnormalities in children, such as coronary artery anomalies, aberrant coronary artery anatomy specific to congenital heart disease, Kawasaki disease, Williams syndrome, and cardiac allograft vasculopathy.


Subject(s)
Child , Child, Preschool , Coronary Angiography/methods , Coronary Vessel Anomalies/diagnostic imaging , Coronary Vessels/diagnostic imaging , Diagnostic Imaging , Echocardiography/methods , Female , Heart Defects, Congenital/diagnostic imaging , Heart Diseases/diagnosis , Heart Rate , Humans , Magnetic Resonance Angiography/methods , Male , Mucocutaneous Lymph Node Syndrome/diagnostic imaging , Tomography, X-Ray Computed/methods
16.
Article in English | WPRIM | ID: wpr-184378

ABSTRACT

OBJECTIVE: The aim of this study was to determine the interobserver and intermodality agreement in the interpretation of time-of-flight (TOF) MR angiography (MRA) for the follow-up of coiled intracranial aneurysms with the Enterprise stent. MATERIALS AND METHODS: Two experienced neurointerventionists independently reviewed the follow-up MRA studies of 40 consecutive patients with 44 coiled aneurysms. All aneurysms were treated with assistance from the Enterprise stent and the radiologic follow-up intervals were greater than 6 months after the endovascular therapy. Digital subtraction angiography (DSA) served as the reference standard. The degree of aneurysm occlusion was determined by an evaluation of the maximal intensity projection (MIP) and source images (SI) of the TOF MRA. The capability of the TOF MRA to depict the residual flow within the coiled aneurysms and the stented parent arteries was compared with that of the DSA. RESULTS: DSA showed stable occlusions in 25 aneurysms, minor recanalization in 8, and major recanalization in 11. Comparisons between the TOF MRA and conventional angiography showed that the MIP plus SI had almost perfect agreement (kappa = 0.892, range 0.767 to 1.000) and had better agreement than with the MIP images only (kappa = 0.598, range 0.370 to 0.826). In-stent stenosis of more than 33% was observed in 5 cases. Both MIP and SI of the MRA showed poor depiction of in-stent stenosis compared with the DSA. CONCLUSION: TOF MRA seemed to be reliable in screening for aneurysm recurrence after coil embolization with Enterprise stent assistance, especially in the evaluation of the SI, in addition to MIP images in the TOF MRA.


Subject(s)
Angiography, Digital Subtraction/methods , Cerebral Angiography/methods , Embolization, Therapeutic/instrumentation , Female , Follow-Up Studies , Humans , Intracranial Aneurysm/diagnosis , Magnetic Resonance Angiography/methods , Male , Middle Aged , Observer Variation , Recurrence , Reference Standards , Stents
17.
J. vasc. bras ; 12(2): 129-132, jun. 2013. graf
Article in English | LILACS | ID: lil-687317

ABSTRACT

This article describes the VascMorph 1a prototype software and reports first results obtained with postoperative determination of the degree of stenosis in the carotid artery.


Este artigo descreve o programa protótipo VascMorph 1a e apresenta os primeiros resultados obtidos com a determinação pós-operatória do grau de estenose na artéria carótida.


Subject(s)
Humans , Carotid Stenosis/diagnosis , Carotid Stenosis/therapy , Magnetic Resonance Angiography/methods , Postoperative Care
18.
Medisan ; 17(1): 140-147, ene. 2013.
Article in Spanish | LILACS | ID: lil-665624

ABSTRACT

Se describen 3 casos clínicos de pacientes ingresados en el Hospital General Docente Dr Juan Bruno Zayas Alfonso de Santiago de Cuba por sospecharse la presencia de aneurismas cerebrales, teniendo en cuenta las manifestaciones neurológicas que presentaban. Mediante los estudios de resonancia magnética y angiorresonancia realizados, se observaron las imágenes de la lesión vascular, las cuales fueron confirmadas por angiografía carotídea


Three clinical cases of patients admitted in Dr Juan Bruno Zayas Alfonso Teaching General Hospital in Santiago de Cuba due to the suspicious presence of cerebral aneurysms are described, keeping in mind the neurological manifestations they presented. By means of the studies of magnetic resonance and angiographic resonance carried out, the images of the vascular lesion were observed, which were confirmed by carotid angiography


Subject(s)
Humans , Female , Middle Aged , Intracranial Aneurysm/diagnosis , Cerebral Angiography/methods , Magnetic Resonance Angiography/methods
19.
Rev. chil. radiol ; 19(3): 109-113, 2013. ilus
Article in Spanish | LILACS | ID: lil-695018

ABSTRACT

Introducción: La angiografía por resonancia magnética no contrastada realizada con "Arterial Spin Labeling" (ARM ASL) es un método diseñado para marcar los espines sanguíneos y así crear un contraste endógeno adecuado para evaluar territorios vasculares selectivamente sin la necesidad de aplicar medio de contraste intravenoso (compuestos de Gadolinio). Metodología: Se realizó un estudio descriptivo de una serie de casos, donde se describen los detalles técnicos y los resultados de la aplicación de la ARM ASL en equipos de 1.5 y 3 Tesla en voluntarios sanos. Resultados: Se observaron dos casos: Para la técnica angiográfica del primer caso (ASL "Flow-in") se usó un resonador de 3T, sincronización cardiaca, una secuencia b-SSFP 3D y un pre-pulso de inversión, este último para saturar los tejidos estáticos. El volumen de examen se ubicó en el plano axial teniendo la precaución de cubrir la anatomía vascular renal, lo cual se logra en la mayoría de los casos con 60 a 70 cortes de 2 mm solapados en 50 porciento, voxel de 2x1x1 mm y campo de visión (FOV) de 250x100 mm. El protocolo del segundo caso fue obtenido en un equipo de 1.5T, sin sincronización cardiaca, con un navegador respiratorio dia fragmático y con una secuencia coronal Turbo SE 3D después de aplicar dos pre-pulsos de marcación sanguínea, el primero similar al del caso anterior y el segundo, o pulso selectivo, para marcar el flujo del vaso de interés. Con este método (ASL "Flow-Out") sólo la sangre marcada emite señal. Conclusión: Las técnicas de angiografía b-SSFP 3D y Turbo SE 3D no contrastadas con pre-pulsos de ASL en 1.5 y 3T son alternativas disponibles y, por lo tanto, pueden considerarse como complemento a otros métodos de angiografía por resonancia magnética al momento de evaluar la patología vascular.


Introduction: Non-contrast magnetic resonance angiography using "Arterial Spin Labeling" (MRA ASL) is a technique designed to label blood spins and therefore create an endogenous contrast suitable for selectively evaluating vascular territories without intravenous contrast (Gadolinium compounds). Methodology: Technical details and results of the implementación of the MRA ASL using 1.5 and 3.0 Tesla systems in healthy volunteers is described. Results: Two cases were observed: for the angiographic technique of the first case (ASL "Flow-in") in a 3.0 T unit, cardiac synchronization (cardiac gating), a 3D b-SSFP sequence, and an inversion pre-pulse was used, the latter to saturate the static tissues. The examination volume was located in the axial plane taking care to cover the renal vascular anatomy, which is achieved in most cases with 60 to 70 2 mm slices overlapped in 50%, voxel of 2x1x1 mm and a field of vision (FOV) of 250 x100 mm. The protocol for the second case was obtained on a 1.5 T system, without cardiac gating, with a diaphragmatic respiratory navigator and a 3D Turbo SE coronal sequence after applying two pre-pulse blood saturation bands, the first similar to the previous case and the second, or selective pulse, to label the flow of the vessel of interest. With this method (ASL "Flow-Out") only the labeled blood emits a signal. Discussion: 3D b-SSFP and 3D Turbo SE non-contrast angiography techniques with ASL pre-pulses in 1.5 and 3T are available alternatives and, therefore, can be considered as a complement to other methods of magnetic resonance angiography when assessing vascular pathology.


Subject(s)
Humans , Magnetic Resonance Angiography/methods , Spin Labels
20.
Article in English | WPRIM | ID: wpr-184186

ABSTRACT

OBJECTIVE: To investigate the feasibility of a rat model on hindlimb ischemia induced by embolization from the administration of polyvinyl alcohol (PVA) particles or N-butyl cyanoacrylate (NBCA). MATERIALS AND METHODS: Unilateral hindlimb ischemia was induced by embolization with NBCA (n = 4), PVA (n = 4) or surgical excision (n = 4) in a total of 12 Sprague-Dawley rats. On days 0, 7 and 14, the time-of-flight magnetic resonance angiography (TOF-MRA) and enhanced MRI were obtained as scheduled by using a 3T-MR scanner. The clinical ischemic index, volume change and degree of muscle necrosis observed on the enhanced MRI in the ischemic hindlimb were being compared among three groups using the analysis of variance. Vascular patency on TOF-MRA was evaluated and correlated with angiographic findings when using an inter-rater agreement test. RESULTS: There was a technical success rate of 100% for both the embolization and surgery groups. The clinical ischemic index did not significantly differ. On day 7, the ratios of the muscular infarctions were 0.436, 0.173 and 0 at thigh levels and 0.503, 0.337 and 0 at calf levels for the NBCA, PVA and surgery groups, respectively. In addition, the embolization group presented increased volume and then decreased volume on days 7 and 14, respectively. The surgery group presented a gradual volume decrease. Good correlation was shown between the TOF-MRA and angiographic findings (kappa value of 0.795). CONCLUSION: The examined hindlimb ischemia model using embolization with NBCA and PVA particles in rats is a feasible model for further research, and muscle necrosis was evident as compared with the surgical model.


Subject(s)
Animals , Disease Models, Animal , Embolization, Therapeutic/adverse effects , Enbucrilate/administration & dosage , Feasibility Studies , Hindlimb/blood supply , Injections, Intra-Arterial , Ischemia/chemically induced , Magnetic Resonance Angiography/methods , Male , Polyvinyl Alcohol/administration & dosage , Rats , Rats, Sprague-Dawley , Tissue Adhesives/administration & dosage
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