Comparison of 3D-arterial spin labeling and digital subtraction angiography in the diagnosis of occlusion and collateral circulation in patients with acute ischemic stroke / 中国医师杂志

Objective:To explore the diagnostic value of 3D-arterial spin labeling (ASL) and digital subtraction angiography (DSA) in the occlusion and collateral circulation (CC) of patients with acute ischemic stroke (AIS).Methods:From January 2019 to June 2020, 53 cases of AIS patients with middle cerebral artery (MCA) occlusion in Langfang Hospital of Traditional Chinese Medicine were selected as the research objects. All patients underwent DSA and 3D ASL examination. According to the gold standard of DSA, the diagnostic value of proximal intra-arterial signal (IAS) in 3D-ASL was observed, and the clinical value of distal IAS in the diagnosis of lateral CC was observed. Univariate and multivariate logistic regression were used to identify risk factors for poor outcome in AIS patients.Results:There were 31 cases with good collateral circulation judged by DSA. Taking DSA as the gold standard, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of digital IAS in diagnosing CC status were 93.55%, 81.82%, 87.88%, 90.00% and 88.68%, respectively. The National Institutes of Health Stroke Scale (NIHSS) score of patients with good CC assessed by 3D-ASL was lower than that of patients with poor CC at admission, and the good prognosis rate at discharge was higher than that of patients with poor CC, with statistically significant difference (all P<0.05). There was no significant difference in clinical data between patients with good CC and those with poor CC, such as gender, age, history of atrial fibrillation, hypertension, diabetes, smoking, drinking, onset to treatment time, treatment methods, etc (all P>0.05). Univariate and multivariate analysis showed that poor CC assessed by ASL was a risk factor for poor prognosis in AIS patients ( OR=5.897, P<0.05). Conclusions:The proximal and distal IAS of 3D-ASL can provide important diagnostic clues for detecting arterial occlusion and collateral perfusion in patients with AIS, and the detection of CC by ASL is of great value for prognosis.

Braided stent-assisted coil embolization versus laser engraved stent-assisted coil embolization in patients with unruptured complex intracranial aneurysms

Abstract Purposes: Braided and laser-cut stents both are efficacious and safe for coiling intracranial aneurysms. The study aimed to compare outcomes following braided stent-assisted coil embolization versus laser engraved stent-assisted coil embolization in 266 patients who were diagnosed with unruptured intracranial aneurysms of different types and locations. Methods: Patients with unruptured complex intracranial aneurysms underwent braided (BSE cohort, n = 125) or laser engraved (LSE cohort, n = 141) stent-assisted embolization. Results: The deployment success rate was higher for patients of the LSE cohort than those of the BSE cohort (140 [99%] vs. 117 [94%], p = 0.0142). Seventy-one (fifty-seven percentages) and 73 (52%) were coil embolization procedure success rates of the BSE and the LSE cohorts. Periprocedural intracranial hemorrhage was higher in patients of the BSE cohort than those of the LSE cohort (8 [6%] vs. 1 [1%], p = 0.0142). Four (three percentages) patients from the LSE cohort and 3 (2%) patients from the BSE cohort had in-stent thrombosis during embolization. Permanent morbidities were higher in patients of the LSE cohort than those of the BSE cohort (8 [6%] vs. 1 [1%], p = 0.0389). Higher successful procedures (76% vs. 68%) and fewer postprocedural intracranial hemorrhage (0% vs. 5%) and mortality (0% vs. 5%) were reported for patients of the BSE cohort in posterior circulation aneurysmal location than those of the LSE cohort. Laser engraved stent has fewer problems with deployment and may have better periprocedural and follow-up outcomes after embolization. Conclusions: Braided stent-assisted embolization should be preferred when the aneurysm is present in the posterior circulation.

Clinical value of high-resolution vessel wall imaging and silent magnetic resonance angiography in re-examination after intracranial aneurysm embolization / 中华神经科杂志

Objective:To explore the clinical application of time of flight-magnetic resonance angiography (TOF-MRA), silent magnetic resonance angiography (SilenZ-MRA) and high-resolution vessel wall imaging (HR-VWI) in non-invasive evaluation of intracranial aneurysm after embolization.Methods:From February 2021 to February 2022, 39 patients, including 8 males and 31 females, who were 29-86 (54.50±11.80) years old and had received intracranial aneurysm embolization were collected in the Second Affiliated Hospital of Nanchang University. Kruskal-Wallis test was used to compare the image quality score and the evaluation results of lumen stenosis rate in the stent segments by TOF-MRA, SilenZ-MRA and HR-VWI. The diagnostic value of TOF-MRA, SilenZ-MRA and HR-VWI was analyzed by receiver operating characteristic (ROC) curve with DSA as the reference standard.Results:The image quality scores of TOF-MRA, SilenZ-MRA and HR-VWI were 2(1, 3), 4(3, 4) and 4(4, 4), respectively, with statistically significant difference ( H=80.78, P<0.05). The pairwise comparison results were as follows: TOF-MRA vs SilenZ-MRA, P<0.017; TOF-MRA vs HR-VWI, P<0.017; SilenZ-MRA vs HR-VWI, P>0.017. The lumen stenosis rates of stent segments measured by TOF-MRA, SilenZ-MRA, HR-VWI and DSA were 45.00% (29.60%, 61.05%), 17.60% (10.80%, 26.80%), 13.35% (8.90%, 15.95%) and 7.95% (4.80%, 11.25%), respectively, with statistically significant difference ( H=67.96, P<0.05). The results of comparison between TOF-MRA, SilenZ-MRA, HR-VWI and DSA were respectively as follows: TOF-MRA vs DSA, P<0.017; SilenZ-MRA vs DSA, P<0.017; HR-VWI vs DSA, P>0.017. DSA review showed that 12 (27.91%,12/43) aneurysms were not completely embolized, and 31 (72.09%, 31/43) aneurysms were completely embolized. The area under the curve of TOF-MRA, SilenZ-MRA and HR-VWI for evaluating the postoperative complete embolization of aneurysm was 0.75, 1.00 and 0.94, respectively, with statistically significant differences between TOF-MRA and HR-VWI ( Z=2.53, P<0.05) as well as between TOF-MRA and SilenZ-MRA ( Z=3.32, P<0.05). Conclusions:HR-VWI can clearly display the stent-segment lumen of the parent artery, and evaluate the stent-segment arterial wall and whether the stent-segment lumen is unobstructed or not. SilenZ-MRA is significantly superior to TOF-MRA in the evaluation of postoperative embolization status of aneurysms, and slightly superior to HR-VWI in tumor neck display. Combined application of HR-VWI and SilenZ-MRA has certain clinical significance for non-invasive evaluation of intracranial aneurysm after embolization.

The role of neuroimaging in the determination of brain death / O papel da neuroimagem na determinação da morte encefálica

Abstract Brain death is the irreversible cessation of all brain function. Although protocols for its determination vary among countries, the concept of brain death is widely accepted, despite ethical and religious issues. The pathophysiology of brain death is related to hypoxia and ischemia in the setting of extensive brain injury. It is also related to the effects of brain edema, which increases intracranial pressure, leading to cerebral circulatory arrest. Although the diagnosis of brain death is based on clinical parameters, the use of neuroimaging to demonstrate diffuse brain injury as the cause of coma prior to definitive clinical examination is a prerequisite. Brain computed tomography (CT) and magnetic resonance imaging (MRI) demonstrate diffuse edema, as well as ventricular and sulcal effacement, together with brain herniation. Angiography (by CT or MRI) demonstrates the absence of intracranial arterial and venous flow. In some countries, electroencephalography, cerebral digital subtraction angiography, transcranial Doppler ultrasound, or scintigraphy/single-photon emission CT are currently used for the definitive diagnosis of brain death. Although the definition of brain death relies on clinical features, radiologists could play an important role in the early recognition of global hypoxic-ischemic injury and the absence of cerebral vascular perfusion.

Resumo A morte encefálica é a cessação irreversível de todas as funções cerebrais. Embora os protocolos para sua determinação variem entre os países, o conceito de morte encefálica é amplamente aceito, apesar de questões éticas e religiosas. A fisiopatologia da morte encefálica está relacionada a hipóxia e isquemia no cenário de uma lesão cerebral difusa. Também está relacionada aos efeitos do edema cerebral, que aumenta a pressão intracraniana, levando à parada da circulação cerebral. Embora o diagnóstico de morte encefálica seja baseado em parâmetros clínicos, o uso de neuroimagem para demonstrar lesão cerebral difusa como causa do coma antes do exame clínico definitivo é um pré-requisito. A tomografia computadorizada (TC) e a ressonância magnética (RM) de crânio demonstram edema difuso e apagamento de ventrículos e sulcos, associados a herniações transcompartimentais. A angio-TC e a angio-RM demonstram a ausência de fluxo arterial e venoso intracraniano. Em alguns países, a eletroencefalografia, a angiografia por subtração digital cerebral, a ultrassonografia transcraniana com Doppler ou a cintilografia/TC por emissão de fóton único são atualmente usadas para o diagnóstico definitivo de morte encefálica. Embora a definição de morte encefálica dependa de características clínicas, os radiologistas podem desempenhar papel importante no reconhecimento precoce da lesão hipóxico-isquêmica global e da ausência de perfusão vascular cerebral.

Anomalía coronaria sospechada por el signo "RAC" en resonancia magnética cardíaca / Anomalous coronary artery suspected by cardiac magnetic resonance "RAC" sign

Abstract A 63 year-old-male was admitted with a non-ST-segment elevation acute coronary syndrome. Due to poor acoustic windows ventricular function could not be evaluated by echocardiography. Magnetic resonance (CMR) revealed normal biventricular size and function without fibro- sis and portraying a rare finding consisting of a tubular structure originated in the aortic root following a retro aortic course between the aorta and left atrium, traversing through the atrioventricular groove. These characteristics raised the suspicion of an anomalous coronary artery origin. Coronary angiography confirmed the presence of two coronary arteries, the right coronary artery (RCA) and the left circumflex artery (LCx) originating from the right coronary sinus via two separate ostia. The LCx followed a retro aortic course proximally be- fore irrigating the left ventricular lateral wall. From the left coronary sinus, the left anterior descending artery followed its normal course with a thin diagonal vessel that presented an acute plaque. Due to these low-risk findings, medical management was chosen.

Analysis of clinical characteristics of three patients with dural arteriovenous fistula manifesting as bithalamic lesions / 中华神经科杂志

Objective:To analyze the clinical presentation, potential pathogenesis, diagnosis, management and prognosis of dural arteriovenous fistula (DAVF) manifesting as bithalamic lesions.Methods:The clinical data of three patients with DAVF manifesting as bithalamic lesions from the First Affiliated Hospital of Xi'an Jiaotong University between August 2019 and August 2020 were analyzed retrospectively, and related literatures were reviewed.Results:Patient 1, a 56-year-old female, presented with a one-month aggressive clinical course of weakness, somnolence, nausea, vomiting, urine incontinence and sitting instability. Patient 2, a 53-year-old male, presented with a one-month aggressive clinical course of disturbance of consciousness, walking with difficulty and decreased higher cortex function. Patient 3, a 68-year-old male, presented with an eight-day aggressive clinical course of memory loss, disturbance of consciousness and mental symptoms. In these three patients, cranial computed tomography (CT) scans showed bilateral hypodensity shadow in thalamus while magnetic resonance imaging (MRI) demonstrated bithalamic edema. Magnetic resonance angiography (MRA) or computed tomography angiography (CTA) presented venous or venous sinus closely related with arteries. Digital substraction angiography (DSA) of the patient 1 demonstrated bilateral occipital artery-straight sinus DAVF treated with surgical excision. Four months later, the patient was consciousness with modified Rankin scale (mRS) score of 5. DSA of the patient 2 demonstrated DAVF supplied by the right external carotid artery and the symptoms were relieved after endovascular embolization. One year after operation, there was no recurrence and mRS score was 2. DSA of the patient 3 demonstrated occipital sinusional area DAVF treated with surgical excision. More than one year after surgery, the patient was conscious with mRS score of 5.Conclusions:DAVF-induced bithalamic lesions is a rare disorder in which clinical presentations are not specific.When cranial CT or MRI demonstrating bithalamic lesions, MRA or CTA showing venous or venous sinus closely related with arteries or presenting with disturbance of consciousness or cognitive decline, DAVF should be considered. DSA is the gold standard for diagnosis of DAVF. Endovascular embolization and surgical excision are the main treatments of DAVF.

Elastase injection into the cerebellomedullary cistern to induce a model of vertebrobasilar dolichoectasia in mice and evaluation of magnetic resonance angiography / 国际脑血管病杂志

Objective:To investigate the effect of magnetic resonance angiography (MRA) in evaluating the mouse model of vertebrobasilar dolichoectasia (VBD) induced by injection of elastase into cerebellomedullary cistern.Methods:Twenty-four male C57/BL6 mice were selected. The mice in the elastase group ( n=12) were injected in the cerebellomedullary cistern with 2.5 μl of phosphate buffer containing 25 mU elastase, and the mice in the saline control group ( n=12) were injected with the same volume of normal saline. MRA examination of the brains of living mice was performed 2 weeks after modeling. Successful modeling was defined as the basilar artery bending angle ≤170°, or the basilar artery bending length accounts for ≥10%, or the basilar artery deviated from the midline by more than 1 grade, or the percentage increase in artery diameter was ≥25%. Results:In the elastase group and the saline control group, 2 mice and 1 mouse did not wake up normally or died, respectively. The 11 surviving mice in the saline control group had no obvious vertebral artery and basilar artery abnormalities. The success rate of modeling in the 10 surviving mice in the elastase group was 80%, and the difference in the success rate between the two groups was statistically significant ( P<0.05). There were significant differences in mean basilar artery diameter (0.30 mm vs. 0.22 mm; P<0.05), mean basilar artery bending angle (115° vs. 170°; P<0.05), and proportion of mean basilar artery bending length (31% vs. 5%; P<0.05) of the surviving mice between the elastase group and the saline control group. Conclusion:MRA can better evaluate the mouse VBD model induced by elastase injection in the cerebellomedullary cistern.

Clinical significance of FLAIR vascular hyperintensities in patients with chronic atherosclerotic middle cerebral artery occlusion / 国际脑血管病杂志

Objective:To investigate the clinical significance of fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVHs) in patients with chronic atherosclerotic middle cerebral artery occlusion.Methods:From July 2016 to November 2020, patients admitted to the Department of Neurology, Jiangdu People's Hospital of Yangzhou and first found chronic atherosclerotic middle cerebral artery occlusion were enrolled. The demographic, clinical and MRI imaging data were collected. According to the presence or absence of acute cerebral infarction, they were divided into the non-acute cerebral infarction group and the acute cerebral infarction group. According to the modified Rankin Scale score at 3 months after the onset, patients with acute cerebral infarction were further divided into the good outcome group (≤2) and the poor outcome group (>2). A multivariate logistic regression model was used to analyze the independent correlation between FVHs and the risk of cerebral infarction in patients with chronic atherosclerotic middle cerebral artery occlusion and the outcome in patients with cerebral infarction. Results:A total of 94 patients with chronic atherosclerotic middle cerebral artery occlusion were enrolled, including 38 with non-acute cerebral infarction (40.4%) and 56 with acute cerebral infarction (59.6%). In patients with acute cerebral infarction, 13 (23.2%) had a poor outcome, and 43 (76.8%) had a good outcome. The fibrinogen level, the proportion of patients with FVHs and the FVHs score in the cerebral infarction group were significantly higher than those in the non-cerebral infarction group (all P<0.05). Multivariate logistic regression analysis showed that the FVHs score was significantly, independently, and positively correlated with the risk of acute cerebral infarction (odds ratio 2.524, 95% confidence interval 1.400-4.552; P=0.002). The National Institutes of Health Stroke Scale score at admission, the modified Rankin Scale score at admission, and FVHs score in the poor outcome group were significantly higher than those in the good outcome group (all P<0.05). Multivariate logistic regression analysis showed that there was a significant independent negative correlation between the FVHs score and the outcome of patients with cerebral infarction (odds ratio 0.144, 95% confidence interval 0.045-0.459; P=0.001). Conclusions:FVHs suggest that the blood supply is in a state of decompensation. When FVHs are present, the risk of cerebral infarction in patients with chronic middle cerebral artery occlusion is significantly increased; the wider the range of FVHs, the higher the risk of poor outcome after cerebral infarction.

High-resolution magnetic resonance imaging vascular wall characteristics and risk of ischemic stroke in patients with middle cerebral artery atherosclerotic stenosis / 国际脑血管病杂志

Objective:To investigate the correlation between the high-resolution magnetic resonance imaging (MRI) vessel wall characteristics and risk of ischemic stroke in patients with middle cerebral artery (MCA) atherosclerotic stenosis.Methods:Patients with ischemic cerebrovascular disease treated in the Department of Neurology, Nanjing First Hospital, Nanjing Medical University from January 2016 to January 2020 were enrolled prospectively. The patients presented with transient ischemic attack or acute ischemic stroke (AIS). Magnetic resonance angiography showed that the ipsilateral MCA had stenosis of 50%-99%, and it was identified as the responsible lesion. Routine MRI and the vessel wall imaging at the narrowest part of MCA were performed. The characteristics of vessels and plaques at MCA stenosis were compared between the AIS group and the non-AIS group. Multivariate logistic regression analysis was used to determine the independent risk factors for AIS. Receiver operating characteristic (ROC) curve was used to determine the predictive value of vessel wall characteristics for AIS. Results:A total of 65 patients with ischemic cerebrovascular disease and MCA stenosis were enrolled. The age of patients was 68±14 years, 50 were males (76.9%). There were 30 patients (46.2%) in the AIS group and 35 (53.8%) in the non-AIS group. There were no significant differences in demographic data, vascular risk factors and routine laboratory tests between the two groups. Compared with the non-AIS group, the narrowest lumen area in the AIS group (2.36±1.09 mm 2vs. 2.96±1.01 mm 2; t=2.274, P=0.027) was smaller, the plaque area (4.46 ±2.08 mm 2vs. 2.62±1.32 mm 2; t=4.315, P<0.001) was larger, the remodeling index (1.08±0.11 vs. 0.94±0.10; t=5.573, P<0.001) was higher, and the proportion of obvious enhanced plaque (63.3% vs. 11.4%; χ2=19.034, P<0.001) and positive remodeling plaque (80.0% vs. 20.0%; χ2=23.311, P<0.001) were higher. Multivariate logistic regression analysis showed that plaque area (odds ratio [ OR] 2.01, 95% confidence interval[ CI] 1.35-2.98; P=0.001), remodeling pattern ( OR 16.00, 95% CI 4.73-54.15; P=0.001), the narrowest lumen area ( OR 0.568, 95% CI 0.34-0.96; P=0.033) and degree of enhancement ( OR 21.85, 95% CI 5.13-93.00; P<0.001) were the independent risk factors for AIS. ROC curve analysis showed that the combination of plaque area, the narrowest lumen area and the degree of enhancement had the best prediction effect (area under the curve 0.927, 95% CI 0.84-0.96). Conclusion:AIS is more likely to occur when the plaque area at the narrowest part of the MCA is larger, the lumen area is smaller, and there is obvious plaque enhancement.

Correlation of fluid-attenuation inversion recovery vascular hyperintensity and clinical outcome in patients with middle cerebral artery M1 occlusive stroke / 国际脑血管病杂志

Objective:To investigate the correlation of fluid-attenuation inversion recovery (FLAIR) vascular hyperintensity (FVH) and clinical outcome in patients with middle cerebral artery M1 occlusive stroke.Methods:Patients with acute middle cerebral artery M1 occlusive stroke admitted to the Department of Neurology, the Second Affiliated Hospital of Anhui Medical University from June 2018 to September 2019 were enrolled retrospectively. The demographic and clinical data were collected. Diffusion-weighted imaging (DWI)-Alberta Stroke Program Early CT Score (ASPECTS) and FVH score were performed with MRI images. The modified Rankin Scale (MRS) was used to evaluate the clinical outcome at 90 d after onset. 0-2 was defined as good outcome, and >2 was defined as poor outcome. Multivariate logistic regression analysis was used to determine the independent correlation between FVH and the outcome. Results:A total of 65 patients with acute middle cerebral artery M1 occlusive stroke were enrolled, including 37 males (56.9%). Their age was 64.35±12.13 years. Twenty-nine patients (44.6%) had a good outcome, and 36 (55.4%) had a poor outcome. There were significant differences in triglyceride ( P=0.037), antihypertensive drug treatment ( P=0.037), baseline National Institutes of Health Stroke Scale (NIHSS) score ( P<0.001), DWI-ASPECTS ( P=0.017) and FVH score ( P<0.001) between the poor outcome group and the good outcome group. Multivariate logistic regression analysis showed that FVH score (odds ratio 6.477, 95% confidence interval 1.570-26.716; P=0.010) and NIHSS score (odds ratio 1.869, 95% confidence interval 1.326-2.635; P<0.001) were significantly independently correlated with the poor outcome. However, there was no significant independent correlation between DWI-ASPECTS and the outcome (odds ratio 0.451, 95% confidence interval 0.068-2.988; P=0.410). Conclusions:FVH score is an independent risk factor for poor outcome in patients with acute middle cerebral artery M1 occlusive stroke.

Risk factors and early neurological deterioration in proximal single subcortical infarction: comparison with distal single subcortical infarction / 国际脑血管病杂志

Objective:To investigate the risk factors for different types of single subcortical infarction (SSI) in middle cerebral artery territory and the risk factors for early neurologic deterioration (END).Methods:Patients with SSI in middle cerebral artery territory admitted to the Department of Neurology, People's Hospital Affiliated to Jiangsu University from January 2020 to April 2021 were enrolled retrospectively. According to the distribution of infarction, the patients were divided into proximal SSI (pSSI) and distal SSI (dSSI). The demographics, vascular risk factors and baseline clinical data were collected. END was defined as new signs and/or symptoms of neurological deficit or aggravation of any neurological deficit within 2 weeks after onset. Multivariate logistic regression analysis was used to determine the independent risk factors for pSSI and END. Results:Seventy-six patients with acute SSI in the middle cerebral artery territory were included, 41 patients (53.9%) in the pSSI group, 35 (46.1%) in the dSSI group; 13 (17.1%) in the END group, and 63 (82.9%) in the non-END group. There were no significant differences in age, gender, vascular risk factors and baseline National Institutes of Health Stroke Scale score between the pSSI group and the dSSI group. The total cholesterol, fasting blood glucose levels and the ratio of pSSI in the END group were significantly higher than those in the non-END group ( P<0.05), while the high-density lipoprotein cholesterol level was significantly lower than that of the non-END group ( P<0.05). Multivariate logistic regression analysis showed that pSSI was an independent risk factor for the occurrence of END in patients with SSI (odds ratio 6.75, 95% confidence interval 1.26-36.23; P=0.026). Conclusion:There was no significant difference in risk factors between pSSI and dSSI, but patients with pSSI were more prone to END.

Clinical Value of 1.5-T Non-contrast Whole-heart Magnetic Resonance Coronary Angiography in Evaluating the Severity of Coronary Stenosis / 中国医学科学院学报

Objective To evaluate the diagnostic performance of 1.5-T non-contrast free-breathing whole-heart magnetic resonance coronary angiography(MRCA)for≥50% and≥70% coronary artery stenosis in coronary artery disease(CAD).Methods Forty-one patients clinically scheduled for invasive coronary angiography(ICA)underwent 1.5-T non-contrast free-breathing whole-heart MRCA.The diagnostic performance for≥50% and≥70% stenosis was evaluated and compared using ICA as a reference standard.Results MRCA was completed in all the 41 patients with the total acquisition time of(10.1 ± 2.2)min.The sensitivity,specificity,and accuracy of MRCA for≥50% and≥70% stenosis were 100%(95%

Carotid web: septo o banda carotídea: presentación de dos casos / Carotid web: "septo o banda carotidea": Two case reports

RESUMEN Carotid web es un término usado para describir en imágenes una anomalía vascular del desarrollo del sistema braquiocefálico. Se trata de una causa poco reconocida de accidente cerebrovascular, especialmente en pacientes jóvenes. Su frecuencia en la población general no se ha determinado y se asocia con eventos cerebrovasculares isquémicos de tipo embólico. En este reporte describimos dos casos de web carotídeo sintomático, uno que se manifiesta como un ataque isquémico transitorio (AIT) y el otro como infarto cerebral. Hasta el momento, no existe un método diagnóstico establecido como óptimo; la angiografía por resonancia magnética y por tomo-grafía se presentan como una opción confiable y alternativa a la angiografía convencional. Una vez identificado el carotid web, la evidencia es escasa con respecto a su manejo; algunas opciones con las que contamos son antiagregación, anticoagulación y manejo invasivo con endarterectomía y colocación de stent. Se dispone de poca literatura en español sobre web carotídeo. A efectos de una mejor comprensión proponemos el término de septo o banda carotídea para denominar a esta anomalía vascular.

SUMMARY Carotid web is a term used to describe by images a vascular abnormality of development of the brachiocephalic system. It is an under-recognized cause of stroke, especially in young patients. Its frequency in the general population has not been determined and is associated with ischemic cerebrovascular events of embolic type. Two cases of symptomatic carotid web are reported, one manifested as a transient ischemic attack (TIA) and the other as a cerebral infarction. There is not an established optimal diagnostic method, MRI and CT angiography are presented as a good option and alternative to conventional angiography. Once the carotid web has been identified, the evidence is scarce regarding its management, there are some options such as antiplatelets, anticoagulation and invasive management with endarterectomy and stent placement, there is little information in Spanish literature on carotid web so we propose the term septo o banda carotidea to name this vascular abnormality.

Signo de la arteria cerebral media hiperdensa e ictus isquémico con transformación hemorrágica / Hyperdense Middle Cerebral Artery Sign and Ischemic Stroke with Hemorrhagic Transformation

RESUMEN El signo de la arteria cerebral media hiperdensa es un patrón imagenológico que tiene una incidencia de un 30 a un 40 % de las oclusiones de esta arteria demostrada angiográficamente. Representa un signo temprano de ictus isquémico de mala evolución. Se presenta el caso de un paciente de 56 años de edad que comenzó con manifestaciones clínicas de afasia y hemiparesia derecha a predominio crural. En la tomografía al ingreso se observó hiperdensidad del trayecto de la arteria cerebral media izquierda que correspondió con un ictus isquémico extenso con conversión hemorrágica en escaneo evolutivo a las 72 horas. Se presenta el caso por lo poco frecuente que resulta realizar este diagnóstico a partir de los resultados hallados en la tomografía axial monocorte y porque hubo correlación entre las imágenes encontradas y el deterioro clínico posterior del paciente.

ABSTRACT The hyperdense middle cerebral artery sign is an imaging pattern that has an incidence from 30 to 40 % of occlusions of this artery demonstrated angiographically. It represents an early sign of poorly progressive ischemic stroke. A 56-year-old patient who began with clinical manifestations of aphasia and right hemiparesis, predominantly femoral it is presented. On admission tomography, hyperdensity of the left middle cerebral artery trajectory was observed, corresponding to an extensive ischemic stroke with hemorrhagic conversion in evolutionary scan at 72 hours. The case is presented because of how infrequent it is to make this diagnosis based on the results found in the single slice axial tomography and because there was a correlation between the images found and the subsequent clinical deterioration of the patient.

Unenhanced magnetic resonance angiography as an accurate alternative in the preoperative assessment of potential living kidney donors with contraindications to computed tomography angiography and to contrast-enhanced magnetic resonance angiography / Angiografia por ressonância magnética sem contraste como uma alternativa acurada na avaliação pré-operatória de possíveis doadores vivos de transplante renal com contraindicações para angiografia por tomografia computadorizada e para angiografia por ressonância magnética com contraste

Abstract Objective: To evaluate the accuracy of steady-state free precession (SSFP) unenhanced magnetic resonance angiography (MRA) at 1.5 T for the identification of multiple renal arteries, using computed tomography angiography (CTA) as the reference standard. Materials and Methods: This was a prospective study involving 39 patients (26 males; mean age, 62.6 years) who underwent CTA and unenhanced MRA to evaluate the proximal and middle segments of the renal arteries. The analysis was performed in two phases: the quality of unenhanced MRA images was classified as diagnostic or nondiagnostic for the presence of multiple renal arteries by two independent readers; two other independent readers then evaluated the images previously classified as being of diagnostic quality. The sensitivity, specificity, and overall accuracy of unenhanced MRA were calculated, CTA being used as the reference standard. The kappa statistic was used in order to calculate interobserver agreement. Results: The image quality of unenhanced MRA was considered diagnostic in 70-90% of the extrarenal arterial segments. The CTA examination revealed 19 multiple renal arteries (8 on the right and 11 on the left). The accuracy of unenhanced MRA for the identification of multiple renal arteries was greater than 90%, with a sensitivity of 72.7-100% and a specificity of 96.3-100%. Conclusion: Unenhanced MRA provides high quality imaging of the extrarenal segments of renal arteries. This method may be used as an alternative for the evaluation of the renal arteries, given that it has an accuracy comparable to that of CTA.

Resumo Objetivo: Avaliar, prospectivamente, a acurácia da angiografia por ressonância magnética (angio-RM) sem contraste, com a sequência steady-state free precession (SSFP) 1,5 T, para a identificação de artérias renais múltiplas, usando para isso a angiografia por tomografia computadorizada (angio-TC) como padrão de referência. Materiais e Métodos: Trinta e nove pacientes (26 do sexo masculino; idade média de 62,6 anos) foram submetidos a angio-TC e angio-RM para avaliação dos segmentos proximais e médios das artérias renais. A análise dividiu-se em duas partes: inicialmente, a qualidade das imagens de angio-RM foi classificada como diagnóstica ou não diagnóstica por dois avaliadores independentes; posteriormente, outros dois avaliadores analisaram as imagens consideradas diagnósticas quanto à presença de múltiplas artérias renais. Sensibilidade, especificidade e acurácia da angio-RM foram calculadas utilizando-se a angio-TC como referência. Estatística kappa foi utilizada para cálculo da concordância interobservador. Resultados: A qualidade das imagens de angio-RM foi considerada diagnóstica em 70-90% dos segmentos arteriais extrarrenais. A angio-TC revelou 19 artérias renais múltiplas (8 direitas e 11 esquerdas). A acurácia da angio-RM para identificação de artérias renais múltiplas foi maior que 90%, com sensibilidade variando de 72,7% a 100% e especificidade variando de 96,3% a 100%. Conclusão: A angio-RM sem contraste proporciona imagens de alta qualidade dos segmentos extrarrenais das artérias renais. Este método pode ser alternativamente utilizado para avaliação renal, com acurácia comparável à da angio-TC.

Feasibility of Non-contrast-enhanced Coronary Magnetic Resonance Angiography at 3.0T / 中国医学科学院学报

To evaluate the feasibility of non-contrast-enhanced magnetic resonance angiography (NCE-MRA) on a 3.0T scanner. Totally 36 volunteers and 24 patients with clinically suspected coronary artery disease underwent NCE-MRA. The quality of the NCE-MRA images was graded for each segment on a four-point scale. The subjects were divided into two groups according to image quality. The age,body mass index (BMI),heart rate,end-expiratory diaphragm displacement,and respiratory diaphragm motion amplitude were evaluated and compared. The average image quality score of every segment was above 2 points. The proximal and middle segments of left anterior descending artery had significantly higher quality scores than the distal segments (=0.000) and the proximal segment of left circumflex coronary artery had significantly higher quality scores than the distal segments (=0.000),the proximal segment of right coronary artery also had a significant higher quality score than its distal segment (=0.001). The image quality was good in 38 subjects (64.4%). The heart rate [(66.35±9.39) beat/min (75.32±11.67) beat/min] (=0.002) and the body mass index [(24.72±3.33) kg/m (27.82±3.61) kg/m ] (=0.002) were significantly different between the good image quality group and the poor image quality group. The end-expiratory diaphragm displacement in good image quality group was (4.43±2.07)mm,which was significantly lower than that in poor image quality group [(9.26±7.62)mm](=0.013). The respiratory diaphragm motion amplitude [(21.35±6.02) mm] in good image quality group was significantly lower than that in poor image quality group [(30.68±14.20)mm](=0.012). NCE-MRA on 3.0T is a feasible tool for visualization of the proximal and middle segments of coronary arteries,and the image quality can be optimized by controlling heart rate and respiration in the future.

Dynamic contrast enhanced MRI quantitative parameters for evaluation of liver fibrosis in children with congenital choledochal cyst / 中国医学影像技术

Objective: To investigate the value of dynamic contrast enhanced MRI (DCE-MRI) quantitative parameters for evaluation of liver fibrosis caused by pediatric congenital choledochal cyst (CCC). Methods: Totally 33 CCC children with liver fibrosis were included into case group, while 14 children were selected as control group. All children underwent liver DCE-MRI. Quantitative parameters were acquired with Tofts model,including volume transfer constant from blood plasma to extravascular extracellular space (Ktrans), transfer rate constant between extravascular extracellular space and blood plasma (Kep) and volume of extravascular extracellular space (Ve). The differences and correlations of the above parameters among different liver fibrosis stages were analyzed, and AUC of each parameter in diagnosing different grades of liver fibrosis were drawn. Results: Ktrans and Kep were significantly different among fibrosis subgroups (all P0.05) and negative correlation with liver fibrosis staging (r=-0.249, P>0.05). AUC for identifying normal vs fibrosis and mild vs advanced fibrosis by Ktrans and Kep were 0.949, 0.748 and 0.933, 0.731, and the cutoff values were 0.239,.0.186 and 1.814, 1.663, respectively. Conclusion: DCE-MRI perfusion parameters such as Ktrans and Kep are valuable for diagnosing and staging of liver fibrosis caused by CCC in children.

Magnetic resonance angiography and transcranial Doppler ultrasound findings in patients with a clinical diagnosis of vertebrobasilar insufficiency

OBJECTIVE: To evaluate the findings of magnetic resonance angiography (MRA) and transcranial Doppler ultrasound (TCD) in patients with a clinical diagnosis of vertebrobasilar insufficiency (VBI). METHOD: From our outpatient neurotology clinic, we selected patients (using the criteria proposed by Grad and Baloh) with a clinical diagnosis of VBI. We excluded patients with any definite cause for vestibular symptoms, a noncontrolled metabolic disease or any contraindication to MRA or TCD. The patients in the study group were sex- and age-matched with subjects who did not have vestibular symptoms (control group). Our final group of patients included 24 patients (study, n=12; control, n=12). RESULTS: The MRA results did not demonstrate significant differences in the findings between our study and control groups. TCD demonstrated that the systolic pulse velocity of the right middle cerebral artery, end diastolic velocity of the basilar artery, pulsatility index (PI) of the left middle cerebral artery, PI of the right middle cerebral artery, and PI of the basilar artery were significantly higher in the study group than in the control group, suggesting abnormalities affecting the microcirculation of patients with a clinical diagnosis of VBI compared with controls. CONCLUSION: MRA failed to reveal abnormalities in patients with a clinical diagnosis of VBI compared with controls. The PI of the basilar artery, measured using TCD, demonstrated high sensitivity (91%) and specificity (91%) for detecting clinically diagnosed VBI.

Síndromes compresivos vasculares: un desafío diagnóstico / Vascular Compressive Syndromes: A Challenge Diagnosis

Resumen Los síndromes de compresión vascular constituyen un grupo de patologías poco frecuentes con prevalencia incierta, no solo por el desconocimiento que se tiene de estos, sino también por su presentación clínica inespecífica. Eso conlleva a que sean infradiagnosticados o detectados en etapas tardías, con secuelas a largo plazo. Su fisiopatología y clínica dependen del tipo de vaso comprometido, el sitio anatómico afectado y la causa subyacente que lo esté produciendo. La anamnesis, el examen físico dirigido y el uso de métodos complementarios como la ultrasonografía Doppler y la angiografía por tomografía computarizada (ATC) o angiografía por resonancia magnética (ARM), son herramientas vitales para su correcto diagnóstico, planificación terapéutica y seguimiento.

Abstract Vascular compression syndromes constitute a group of rare pathologies with uncertain prevalence not only because of their unawareness, but also for its nonspecific clinical presentation. This leads to their underdiagnosis, or detection in late stages with long-term sequelae. Its pathophysiology and presentation depends on the type of vessel involved, the affected anatomical site and the underlying cause producing it. Clinical history, physical examination and use of complementary methods such as Doppler ultrasonography, Computed Tomography Angiography (CTA) or Magnetic Resonance Angiography (MRA), are essential tools for its proper diagnosis, therapeutic planning and follow-up.

Enfermedad quística adventicial de la arteria poplítea: presentación imagenológica de una causa rara de claudicación intermitente / Adventitial cystic disease of the popliteal artery as a cause of intermittent claudication: not your usual suspect: report of one case

Adventitial cystic disease of the popliteal artery is a rare condition of uncertain etiology, which presents as intermittent claudication of the lower extremity in middle-age patients. We report a 44-year-old man presenting with intermittent claudication of his left leg. MR angiography showed cystic parietal lesions that caused compression with partial occlusion of the left popliteal artery. Surgical resection of the affected segment was performed, with venous graft interposition. The histopathological analysis of the surgical specimen was consistent with cystic adventitial disease.