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Periocular recognition has emerged as a particularly valuable biometric identification method in challenging scenarios, such as partially occluded faces due to COVID-19 protective masks masks, in which face recognition might not be applicable. This work presents a periocular recognition framework based on deep learning, which automatically localises and analyses the most important areas in the periocular region. The main idea is to derive several parallel local branches from a neural network architecture, which in a semi-supervised manner learn the most discriminative areas in the feature map and solve the identification problem solely upon the corresponding cues. Here, each local branch learns a transformation matrix that allows for basic geometrical transformations (cropping and scaling), which is used to select a region of interest in the feature map, further analysed by a set of shared convolutional layers. Finally, the information extracted by the local branches and the main global branch are fused together for recognition. The experiments carried out on the challenging UBIRIS-v2 benchmark show that by integrating the proposed framework with various ResNet architectures, we consistently obtain an improvement in mAP of more than 4% over the "vanilla" architecture. In addition, extensive ablation studies were performed to better understand the behavior of the network and how the spatial transformation and the local branches influence the overall performance of the model. The proposed method can be easily adapted to other computer vision problems, which is also regarded as one of its strengths.
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Identificación Biométrica , COVID-19 , Humanos , Algoritmos , Redes Neurales de la Computación , Identificación Biométrica/métodos , Cara/anatomía & histologíaRESUMEN
The neurological manifestations of Crohn's disease and its prevalence are not well known. Here, we report five patients of confirmed Crohn's disease with different neurological presentations. The neurological presentations include anterior ischemic optic neuropathy, myelopathy, posterior reversible encephalopathy syndrome, chronic inflammatory demyelinating polyneuropathy, and chronic axonal sensory and motor polyneuropathy. These manifestations should be kept in mind in the assessment of Crohn's disease.
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BACKGROUND: Hemodynamic depression, including bradycardia and hypotension, is among the most common complications of carotid angioplasty and stenting. METHODS AND MATERIAL: A prospective, cross-sectional study was conducted at Shiraz University of Medical Sciences in southern Iran from 2011 to 2013. Consecutive patients undergoing carotid angioplasty and stenting were included. Demographic data, atherosclerotic risk factors, preprocedural blood pressure, the site of stenosis, the degree of stenosis, and data regarding technical factors were recorded. Hemodynamic depression was defined as a systolic blood pressure less than 90 mmHg and/or heart rate less than 50 beat/min. RESULTS: About 170 patients (67% male, mean age: 71+9.8, 55.9% right side, 82.9% symptomatic) were recruited. Mean degree of stenosis was 79.4% in operated side and 40.7% in nonoperated side. Predilation, postdilation, or both were conducted in 18(10.5%), 141(83%), 11(6.5%) patients respectively. Thirteen (7.6%), 41(24%), and 12(7%) of patients developed postprocedural bradycardia, hypotension or both, respectively. Two patients had a stroke after CAS and periprocedural mortality was 0%. Hemodynamic depression after CAS had a significant association with preprocedure blood pressure and the use of an open cell stent design, but not with atherosclerotic risk factors, site and/or degree of stenosis, predilation, or postdilation. Hemodynamic depression significantly increased hospital stay too. CONCLUSION: Preprocedural hydration and close-cell stents may decrease the risk of poststenting hemodynamic depression.
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BACKGROUND: Carotid angioplasty and stenting (CAS) is an accepted treatment to prevent stroke in patients with carotid artery stenosis. The purpose of this study is to identify risk factors for major complications after CAS. MATERIALS AND METHODS: This is a prospective study that was conducted at Shiraz University of Medical Sciences in southern Iran from March 2011 to June 2014. Consecutive patients undergoing CAS were enrolled. Both standard- and high-risk patients for endarterectomy were enrolled. Demographic data, atherosclerotic risk factors, site of stenosis, degree of stenosis, and data regarding technical factors were recorded. Thirty-day stroke, myocardial infarction, and/or death were considered as the composite primary outcomes of the study. RESULTS: A total of 251 patients were recruited (mean age: 71.1 ± 9.6 years; male: 65.3%). Of these, 178 (70.9%) were symptomatic, 73 (29.1%) were diabetic, 129 (51.4%) were hyperlipidemic, 165 (65.7%) were hypertensive, and 62 (24.7%) patients were smokers. CAS was performed for left internal carotid artery (ICA) in 113 (45.4%) patients. Fourteen (5.6%) patients had sequential bilateral stenting. Mean stenosis of operated ICA was 80.2 ± 13.8%. An embolic protection device was used in 203 (96.2%) patients. Pre- and postdilation were performed in 39 (18.5%) and 182 (86.3%) patients, respectively. Composite outcomes were observed in 3.6% of patients (3.2% stroke, 0% myocardial infarction, and 1.2% death). Left-sided lesions and the presence of diabetes mellitus were significantly associated with poor short-term outcome (p = 0.025 and p = 0.020, respectively). CONCLUSION: There was a higher risk of short-term major complications in diabetic patients and for left carotid artery intervention.
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BACKGROUND: Large artery disease (LAD) is a common cause of stroke, but a little is known regarding its role in Iranian stroke patients. The current study investigates the prevalence and risk factors for cervicocephalic arterial stenosis in the patients with ischemic stroke using digital subtraction angiography (DSA). METHODS: This was a prospective cross-sectional study performed in hospitals affiliated to Shiraz University of Medical Sciences from March 2011 to March 2013. Patients with ischemic stroke underwent noninvasive vascular and cardiac investigations to find the etiology of the stroke. Patients suspected of having large artery stenosis underwent DSA. The severity of the stenosis was calculated according to the North American Symptomatic Carotid Endarterectomy (NASCET) and Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) Trial criteria. The presence of cigarette smoking, hyperlipidemia, hypertension, and diabetes mellitus were documented for all subjects. RESULTS: A total of 3703 stroke patients were identified. Of them, 342 patients (62.3%, male) underwent DSA for LAD. The mean age at the time of angiography was 66.7±10.3 years. Extracranial and intracranial arteries were involved in 305 (89.2%) and 162 (47.4%), respectively. And 301 patients (88%) had anterior circulation and 128 patients (37.4%) had posterior circulation involvement. Diabetes mellitus but not age, sex, hypertension, hyperlipidemia, or smoking was significantly associated with intracranial involvement. (P = 0.002). CONCLUSION: It can be concluded that the distribution of the large arterial atherosclerotic disease in Iran is similar to that seen in North America and Europe. Intracranial stenosis was more prevalent in diabetic patients.
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BACKGROUND: This randomized clinical trial compared rates of stroke or transient ischemic attack recurrence or death in patients with cryptogenic stroke and patent foramen ovale (PFO) who received medical treatment with aspirin or warfarin. MATERIALS AND METHODS: Forty-four Iranian patients with cryptogenic stroke and patent foramen ovale participated in this randomized, single-blind trial between July 2007 and June 2010. All patients underwent transesophageal echocardiography and contrast-transcranial Doppler sonography to confirm the presence of patent foramen ovale. The patients were randomly assigned to receive aspirin or warfarin and were followed for 18 months for the recurrence of ischemic events or death. The principal investigator was blind to the group assignment. This trial is registered under number IRCT138805192323N1. RESULTS: Five (11.4%) patients had a stroke, 2 (4.5%) had a transient ischemic attack and 2 (4.5%) died. There was no difference in the rate of ischemic events or death between the aspirin- and warfarin-treated groups (hazard ratio: 0.45; 95% CI: 0.1-1.8; P = 0.259). CONCLUSION: There was no difference in ischemic event recurrence, death rates or side-effects between patients with cryptogenic stroke and patent foramen ovale who were treated with aspirin vs. warfarin.
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We aimed to compare cerebral artery velocity and relevant clinical factors in patients with ß-thalassemia intermedia (ß-TI), ß-thalassemia major (ß-TM), and healthy individuals. For this study, 60 patients with ß-TM and 64 with ß-TI were randomly selected. Sixty healthy adults comprised the control group. Time average maximum mean velocity (TAMMV) was measured in large cerebral arteries with transcranial Doppler (TCD) ultrasonography. In all arteries, TAMMV was significantly higher in the ß-TI group than that of ß-TM or controls (P < .001). Patients with ß-TM had significantly higher TAMMV than controls in most arteries evaluated (P < .001). Overall, the lack of regular blood transfusions, splenectomy, and lower age (to a lesser extent) was found to be independent influencing factors contributing to high cerebral artery velocities. Further detailed longitudinal studies are needed to confirm these results and to determine the risk of silent infarction and stroke in patients with thalassemia and abnormal TCD, with particular focus on patients with ß-TI.
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Talasemia beta/diagnóstico por imagen , Adulto , Velocidad del Flujo Sanguíneo , Estudios de Casos y Controles , Arterias Cerebrales/diagnóstico por imagen , Arterias Cerebrales/fisiopatología , Estudios Transversales , Femenino , Humanos , Masculino , Ultrasonografía Doppler Transcraneal/métodos , Adulto Joven , Talasemia beta/sangre , Talasemia beta/clasificación , Talasemia beta/fisiopatologíaRESUMEN
Introduction. Patients with ß-thalassemia intermedia have a higher incidence of thromboembolic events compared to the general population. Previous studies have shown that patients with sickle cell disease, who are also prone to ischemic events, have higher intracranial arterial blood flow velocities measured by transcranial Doppler sonography (TCD). The aim of this study is to evaluate intracranial arterial flow velocities in patients with ß-thalassemia intermedia and compare the results with those found in healthy subjects. Methods. Sixty-four patients with ß-thalassemia intermedia and 30 healthy subjects underwent transcranial Doppler sonography. Results. Significantly higher flow velocities were found in intracranial arteries of patients compared to controls (P = 0.001). Previously splenectomized patients with thrombocytosis showed higher flow velocities than nonsplenectomized patients without thrombosis. Conclusion. The increased flow velocities in patients with ß-thalassemia intermedia may point to a higher risk of ischemic events. Preventive measures such as blood transfusion or antiplatelet treatment may be beneficial in these patients.
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BACKGROUND: To evaluate the incidence, frequency, and contributing factors of microembolic signals (MESs) in patients with cryptogenic stroke with or without patent foramen ovale (PFO). METHODS: Transcranial Doppler monitoring for MESs detection was performed for 62 patients with acute cryptogenic stroke with PFO (PFO(+)) and 34 patients with acute cryptogenic stroke without PFO (PFO(-)). RESULTS: The incidence of MESs was not significantly higher in PFO(+) patients (17/62, 27.4%) in comparison to PFO(-) patients (6/34, 17.6%; odds ratio 1.76, 95% confidence interval 0.62-5.00; P = .327). The frequency of MESs in PFO(+) patients was statistically higher than that of PFO(-) patients (0.70 ± 1.47 v 0.23 ± 0.55; P = .026). MESs was presented with higher incidence in a subgroup of patients suffering from both patent foramen ovale and atrial septal aneurysm (P = .044). CONCLUSIONS: The likelihood of PFO as a source of MESs is higher when associated with atrial septal aneurysm.
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Foramen Oval Permeable/epidemiología , Aneurisma Cardíaco/epidemiología , Embolia Intracraneal/epidemiología , Accidente Cerebrovascular/epidemiología , Anciano , Estudios de Casos y Controles , Angiografía Cerebral/métodos , Distribución de Chi-Cuadrado , Ecocardiografía Transesofágica , Femenino , Foramen Oval Permeable/diagnóstico por imagen , Aneurisma Cardíaco/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Humanos , Incidencia , Embolia Intracraneal/diagnóstico por imagen , Irán/epidemiología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Accidente Cerebrovascular/diagnóstico por imagen , Ultrasonografía Doppler TranscranealRESUMEN
OBJECTIVES: To determine the frequency, nature, and risk factors associated with physical injuries in patients with epilepsy. METHODS: In this retrospective cohort study, patients 18years of age and older with active epilepsy for at least 1year were included. A questionnaire (including age, gender, education, type of epilepsy, seizure frequency, having aura, drug compliance, polypharmacy, comorbidity, type and place of injury) was completed from patients and healthy individuals. Statistical analyses were performed using multiple logistic regression and Chi-square tests. RESULTS: 264 patients with epilepsy and 289 healthy participants were studied. Among patients, 8.7% reported severe injuries and 44.3% had mild injuries. Most patients reported soft tissue injuries, followed by dental injury, burn, and head injury. Severe injuries were 2.9 times more frequent among patients having generalized tonic-clonic seizures (GTCS) compared to healthy control; this was not statistically significant (P=0.07). No patient reported having severe injuries due to SPS, myoclonic or absence seizures. Mild injuries were 10.3 times more frequent among those with GTCS compared to healthy control (P=0.001). The relative risk for having injury in patients compared to control group was 3.42 (95% confidence interval: 2.50-4.69). Injury was significantly related to having GTCSs, illiteracy, having fall with seizures, comorbidity and having uncontrolled seizures. CONCLUSION: Physical injuries are common in patients with epilepsy; however most of these injuries are mild. Severe injuries rarely occur in patients with seizures other than GTCS.
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Epilepsia/complicaciones , Convulsiones/complicaciones , Heridas y Lesiones/epidemiología , Adulto , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
PURPOSE: To evaluate a technique for contrast agent preparation as mixing the patients' blood with agitated saline and to compare it with agitated saline alone in diagnosis of cardiac right-to-left shunt in regard to their sensitivity, time window, and distribution of artificially induced microembolic signals. METHODS: Fifty-two patients with stroke who had Transesophageal echocardiography proven right-to-left shunt underwent contrast-transcranial Doppler sonography with injection of agitated (i) 9 ml saline with 1 ml air with Valsalva maneuver, (ii) 9 ml saline with 1 ml air without Valsalva maneuver, (iii) 8 ml saline, 1 ml of the patient's fresh blood and 1 ml air with Valsalva maneuver, and (iv) 8 ml saline, 1 ml of the patient's fresh blood and 1 ml air without Valsalva maneuver. RESULTS: The sensitivity of the bilateral middle cerebral artery monitoring in diagnosis of right-to-left shunt was 94.2%, 71.2%, 96.2% and 76.9% for agitated saline with Valsalva maneuver, agitated saline without Valsalva maneuver, agitated saline and blood with Valsalva maneuver, and agitated saline and blood without Valsalva maneuver methods, respectively. Severe right-to-left shunt was detected in 100% of patients when agitated saline and blood with Valsalva maneuver was used. Application of Valsalva maneuver resulted in detection of more right-to-left shunt (P = 0.002). CONCLUSION: Agitated saline mixed with blood with Valsalva maneuver is a sensitive method to detect right-to- left shunt, especially in the case of severe shunt. Mixing agitated saline with blood may increase the sensitivity of the test.
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Medios de Contraste , Foramen Oval Permeable/diagnóstico por imagen , Cloruro de Sodio , Ultrasonografía Doppler Transcraneal/métodos , Adulto , Anciano , Estudios Transversales , Ecocardiografía Transesofágica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Maniobra de ValsalvaRESUMEN
This study compared the diagnostic efficacy of transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) for patients with stroke. Examination with TTE was followed by TEE. Stroke causes were classified according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) and Causative Classification of Stroke (CCS) criteria before and after TEE to determined, cryptogenic or unclassified groups. We identified that 55.1% of patients had a determined etiology for stroke with TTE; adding TEE to the examinations increased the proportion of patients with determined stroke etiology to 69.4% (κ = 0.79). TTE alone showed fair agreement with the combined results of TTE and TEE in determining the cause of stroke in young adults (κ = 0.38). TEE improved the detection of cardio-aortic sources, but had no impact on patients who had a determined cause for stroke with other examinations. TEE examination was most useful in young adults with stroke and in patients with an undetermined cause for stroke despite TTE examination and other standard investigations.
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Isquemia Encefálica/diagnóstico por imagen , Ecocardiografía Transesofágica , Ecocardiografía , Accidente Cerebrovascular/diagnóstico por imagen , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Accidente Cerebrovascular/etiologíaRESUMEN
BACKGROUND: World Health Organization declared pandemic phase of human infection with novel influenza A (H1N1) in April 2009. There are very few reports about the neurological complications of H1N1 virus infection in the literature. Occasionally, these complications are severe and even fatal in some individuals. The aims of this study were to report neurological complaints and/or complications associated with H1N1 virus infection. METHODS: The medical files of all patients with H1N1 influenza infection admitted to a specified hospital in the city of , from October through November 2009 were reviewed. More information about the patients were obtained by phone calls to the patients or their care givers. All patients had confirmed H1N1 virus infection with real-time PCR assay. RESULTS: Fifty-five patients with H1N1 infection were studied. Twenty-three patients had neurological signs and/or symptoms. Mild neurological complaints may be reported in up to 42% of patients infected by H1N1 virus. Severe neurological complications occurred in 9% of the patients. The most common neurological manifestations were headache, numbness and paresthesia, drowsiness and coma. One patient had a Guillain-Barre syndrome-like illness, and died in a few days. Another patient had focal status epilepticus and encephalopathy. CONCLUSIONS: The H1N1 infection seems to have been quite mild with a self-limited course in much of the world, yet there appears to be a subset, which is severely affected. We recommend performing diagnostic tests for H1N1influenza virus in all patients with respiratory illness and neurological signs/symptoms. We also recommend initiating treatment with appropriate antiviral drugs as soon as possible in those with any significant neurological presentation accompanied with respiratory illness and flu-like symptoms.
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The differentiation of vasovagal syncope and epileptic seizure is sometimes problematic, since vasovagal syncope may mimic epileptic seizures in many ways. The present report describes a patient who had been diagnosed and treated as having epilepsy with medically-refractory seizures for 16 years. Often, unlike epileptic seizures, tonic-clonic convulsions and postictal confusion are uncommon features of vasovagal syncope, but these may occur. Our patient was subjected to subcutaneous injection of one ml normal saline, which caused asystole leading to hypoxia and consequently a typical tonic-clonic convulsion. This patient was proved to have vasovagal syncope. The findings in the present case suggest that the possibility of vasovagal syncope should always be taken into consideration when evaluating patients with medically-refractory or unusual pattern of seizures. In such a circumstance, simultaneous video-electroencephalogram/electocardiogram monitoring may help achieve the correct diagnosis.