Hemorragia Intracerebral Imprevisible en un Hombre Joven: La Importancia de la Tomografía computarizada craneal post-mortem / Unpredictable Intracerebral Hemorrhage in a Young Male: The Importance of Post-Mortem Cranial Computed Tomography

La muerte súbita es aquella que ocurre dentro de las 24 horas posteriores al inicio de los síntomas y se caracteriza por ser clínicamente inexplicable, inesperada y repentina. Debido a la naturaleza de la muerte súbita, no es posible llegar a un diagnóstico preciso sin una autopsia. En esta comunicación breve, evaluaremos el caso de un empleado de crucero de 33 años, sin historial médico/farmacológico previo, el cual falleció súbitamente mientras reposaba en su camarote. Debido a las sospechas iniciales de una posible muerte causada por una sobredosis de cocaína, se le realizó un panel toxicológico abarcador el cual resultó negativo. Empero, una tomografía computarizada (TC) craneal sin contraste revirtió la hipótesis inicial y la autopsia neuropatológica -sorpresivamente- confirmó que la verdadera causa de muerte fue la ruptura de un aneurisma sacular desconocido en el polígono de Willis.

Sudden death occurs within 24 hours after the onset of symptoms and is characterized by being clinically inexplicable, sudden, and unexpected. Due to the nature of sudden death, it is not possible an accurate diagnosis without performing an autopsy. In this brief communication, we will evaluate the case of a 33-year-old cruise employee, with no prior medical/pharmacological history, who suddenly died while resting in his cabin. Due to initial suspicions of a possible cocaine overdose death, a comprehensive toxicology panel was performed, although yielding a negative result. A cranial computed tomography without contrast reversed the initial hypothesis and the neuropathological autopsy -surprisingly- confirmed that the true cause of death was the rupture of an unknown saccular aneurysm in the Circle of Willis.

Anatomical Variations and Clinical Significance of the Cerebral Arterial Circle in Turkish Cadavers / Variaciones Anatómicas y Significancia Clínica del Círculo Arterial Cerebral en Cadáveres Turcos

SUMMARY: The structure formed by the arteries, which is of great importance in the irrigation of the brain, is called the cerebral arterial circle (Polygon of Willis). Since the cerebral arterial circle provides brain nutrition, vascularabnormalities in this region are highly relevant. Therefore, the aim of our study was to examine the variations of the cerebral arterial circle in cadavers of Turkish individuals. In our study, 32 human cadavers obtained from three different universities were retrospectively examined. Brain tissue obtained from cadavers by craniotomy was kept in 20 % formaldehyde solution for an average of 10 days for fixation. Cerebral arterial circle diagrams were determined in all cadavers by staining and photographs were taken. As a result of the brain examinations, a variation of the cerebral arterial circle was detected in 24/32 brains. Vascular variations have an important place in congenital variations. For this reason, we believe that our brain study will contribute to clinical studies on this topic by investigating variations of the cerebral arterial circle.

La estructura formada por las arterias que tiene una gran importancia en la irrigación del cerebro se denomina círculo arterial cerebral (Polígono de Willis). Dado que el círculo arterial cerebral proporciona la irrigación cerebral, las anomalías vasculares en esta región son muy relevantes. Por lo tanto, el objetivo de nuestro estudio fue examinar las variaciones del círculo arterial cerebral en cadáveres de individuos turcos. En nuestro estudio, se examinaron retrospectivamente 32 cadáveres humanos obtenidos de tres universidades diferentes. El tejido cerebral de los cadáveres fue obtenido por craneotomía y se mantuvo en solución de formaldehído al 20 %, durante 10 días en promedio para su fijación. Se determinaron los diagramas de círculo arterial cerebral en todos los cadáveres mediante coloración y se tomaron fotografías. Como resultado de los exámenes, se detectó una variación del círculo arterial cerebral en 24/32 de los cerebros. Las variaciones vasculares tienen un lugar importante en las variaciones congénitas. Por esta razón, creemos que nuestro estudio contribuirá a estudios clínicos sobre el tema al pesquisar las variaciones del círculo arterial cerebral.

Thomas Willis' legacy on the 400th anniversary of his birth / O legado de Thomas Willis no 400° aniversário de seu nascimento

Abstract To celebrate the 400th anniversary of the birth of Thomas Willis, his main contributions to the development of neurosciences, in particular neurology, are presented. Willis coined the term neurology and contributed significantly to the field of neuroanatomy, with the description of the arterial circle—located at the base of the brain—, which bears his name. He also described the striatum and cranial nerves. Furthermore, as a clinical neurologist, Willis participated in the description of various diseases, including myasthenia gravis and restless legs syndrome.

Resumo Na comemoração dos 400 anos de nascimento de Thomas Willis, são apresentadas as suas principais contribuições para o desenvolvimento das neurociências, em particular a neurologia. Willis cunhou o termo neurologia, contribuiu significativamente na área de neuroanatomia, com a descrição do círculo arterial localizado na base do cérebro, que tem o seu nome, além da descrição do corpo estriado, e de nervos cranianos. Da mesma forma, como neurologista clínico, Willis participou da descrição de várias doenças como a miastenia gravis e da síndrome das pernas inquietas, entre outras doenças.

Parameter Identification Algorithm of Lumped Parameter Model in the Circle of Willis / 医用生物力学

Objective To explore the application of three parameter identification methods (impedance modulus curve method, impedance component method, and genetic algorithm) in solving parameter identification problem of the 11-element lumped parameter model in the circle of Willis. Methods Using the flow and pressure waveforms of the internal carotid arteries and vertebral arteries on both sides as inlet conditions, parameter values of the model under normal and bilateral vertebral artery stenosis conditions were calculated. The recognition algorithm was verified by using Simulink models, and finally the stability of the recognition algorithm was verified by adding a certain noise to the flow. Results Under normal circumstances, the proximal resistances obtained by the impedance modulus curve method were larger, and the resistances of the anterior communicating artery obtained by the impedance component method were larger. The genetic algorithm could obtain relatively reasonable model parameter values. In the case of vertebral artery stenosis on both sides, the impedance modulus curve method could obviously get the results of the increasement in proximal resistances of the posterior circulation, but the results obtained by the impedance component method and the genetic algorithm mainly lied in that the distal resistance had a larger increase. Conclusions There are still differences between the pressure data calculated by the parameters identified by the above three methods and the actual data, which are considered as modeling errors, source data errors and calculation errors. The impedance modulus curve method has a certain effect in distinguishing changes of the proximal and distal resistances, but there exist large errors in identification of some parameters. The impedance component method can identify the parameters, but this method is unstable with large calculation errors. Genetic algorithm can obtain a better approximate solution, but it has certain problems in distinguishing vertebral artery stenosis. The combination of impedance modulus curve method and genetic algorithm may play a better role in future application of this model for disease diagnosis.

Fetal-type variant of the posterior cerebral artery and concurrent bilateral cerebral infarctions in a Korean male cadaver / Variante de tipo fetal de la arteria cerebral posterior e infartos cerebrales bilaterales concurrentes en un cadáver masculino coreano

SUMMARY: Fetal-type variant of the posterior cerebral artery is a relatively common variant of the cerebral arterial circle (circle of Willis), but concurrent cerebral pathologies have not been well reported. We describe a case of fetal-type variant of the posterior cerebral artery and concurrent bilateral cerebral infarctions in the territories of the middle cerebral artery in a 78-year-old Korean male cadaver. Fetal-type variant of the posterior cerebral artery was found the right cerebral arterial circle, arose from the internal carotid artery with larger diameter than the pre-communicating segment from the basilar artery. Histopathological examination revealed that left supramarginal gyrus and right infraparietal lobule showed characteristic cerebral infarctions with chronological changes, respectively. Knowledge on the variation in the posterior cerebral artery combined with clinical features including cerebral infarction plays a pivotal role to anatomists and clinicians.

RESUMEN: La variante de tipo fetal de la arteria cerebral posterior es una variante relativamente común del círculo arterial cerebral (polígono de Willis) de arterial cerebral, pero las patologías cerebrales concurrentes no han sido bien informadas. Describimos un caso de variante de tipo fetal de la arteria cerebral posterior e infartos cerebrales bilaterales concurrentes en los territorios de la arteria cerebral media en un cadáver masculino coreano de 78 años. La variante de tipo fetal de la arteria cerebral posterior se encontró en la parte de derecha del círculo arterial cerebral, surgido de la arteria carótida interna con mayor diámetro que el segmento precomunicante de la arteria basilar. El examen histopatológico reveló que el giro supramarginal izquierdo y el lóbulo infraparietal derecho mostraban infartos cerebrales característicos con cambios cronológicos, respectivamente. El conocimiento sobre la variación en la arteria cerebral posterior combinado con las características clínicas, incluido el infarto cerebral es fundamental para los anatomistas y los médicos.

Estudio Transversal Hispano-Ecuatoriano: Discapacidades derivadas de Ictus cerebral / Hispano- Ecuadorian Cross-Sectional Study: Disabilities derived from cerebral stroke

INTRODUCCIÓN: En la actualidad el ictus es considerado una de las principales causas de discapacidad en el mundo. Globalmente 5 millones de personas adquieren discapacidad permanente cada año por esta causa; hasta el 30% de los pacientes afectados padecen algún tipo de discapacidad. El manejo temprano del paciente puede disminuir las secuelas derivadas de las lesiones. El objetivo de este estudio es conocer si existen diferencias en las discapacidades derivadas de ictus entre las ciudades de Madrid (España) y Cuenca (Ecuador), en relación a una atención temprana programada. MATERIALES Y MÉTODOS: El presente, es un estudio observacional, descriptivo, de corte transversal, multicéntrico. La muestra estuvo conformada por 40 pacientes diagnosticados de ACV, 20 pertenecientes al Grupo Cuencano, de Ecuador (GC) y 20 al Grupo Matritense, de España (GM). Los datos fueron obtenidos de las historias clínicas. Se compararon ambos grupos mediante la prueba Chi-cuadrado (X2) de Pearson para cada variable estudiada. RESULTADOS: En el GM el 80% de los ACV fueron de origen isquémico, en el GC fueron el 90%, sin asociación significativa. En los dos grupos el mayor porcentaje de secuelas se dieron por afectación del territorio de la arteria cerebral media (ACM). No se evidenció diferencia significativa en el porcentaje de discapacidades derivadas de ictus entre los grupos, el grupo matritense de España presentó una menor tasa de discapacidades derivadas que fue del 45%, frente al grupo cuencano de Ecuador que tuvo un 76% de capacidades derivadas, pero la diferencia no fue significativa (p=0.069); sin embargo la asociación entre el porcentaje de exitus entre los grupos si tuvo asociación estadísticamente significativa (p=0.003). CONCLUSIÓN: No se encontró asociación significativa en cuanto a etiología, factores de riesgos y características clínicas del Ictus entre los grupos. No hay diferencias significativas en las secuelas derivadas de ictus entre los grupos, pero si hay diferencias significativas en relación al porcentaje de exitus con la aplicación de un programa tipo "Código Ictus".

BACKGROUND: Currently, stroke is one of the main causes of disability in the world. Globally 5 million people acquire permanent disability each year for this cause; up to 30% of affected patients suffer from some type of disability. Early management of the patient can reduce the sequelae derived from the injury. The aim of this study is to find out if there are differences in disabilities derived from strokes, between the cities of Madrid (Spain) and Cuenca (Ecuador), in association with programmed early patient care. METHODS: This is an observational, descriptive, cross-sectional, multicenter study. The sample consisted of 40 patients diagnosed with stroke, 20 from Cuenca, Ecuador, and 20 from Madrid, Spain. Data was obtained from the patient's medical records. Both groups were compared using Pearson's Chi-square test (Χ2) for each studied variable. RESULTS: in the Madrid Group 80% of the strokes were ischemic, in the Cuenca Group 90% of the strokes were ischemic, there is not significant association. In both groups the highest percentage of sequelae occurred due to injury of the middle cerebral artery (MCA). There was no significant difference in the percentage of disabilities derived from stroke between the groups, the Madrid Group had a lower rate of derived disabilities (45%), compared to Cuenca Group (76%), but the differences was not significant (p=0.069); however, the association between the death percentage among the groups was statistically significant (p=0.003). CONCLUSION: No significant association was found in terms of etiology, risk factors and clinical characteristics of stroke between the groups. There are no significant differences in the sequelae derived from stroke between the groups, but there is significant difference in terms of death percentage between the groups, with the application of "Código Ictus" type of program.

Hemodynamics Study of Internal Carotid Artery：A Comparison Between Unidirectional and Bidirectional Coupled Multi-Scale Model / 医用生物力学

Objective To compare the hemodynamic characteristics in internal carotid artery models, which were obtained by multi-scale unidirectional and bidirectional coupling models, so as to provide references for selecting models in further studies. Methods Based on the nuclear magnetic resonance image of one patient with mild stenosis of internal carotid artery, the lumped parameter model of the circle of Willis and the three-dimensional model of internal carotid artery were constructed. Those two different multi-scale models were constructed by unidirectional and bidirectional coupling. Results With the increase of stenosis degree, the inlet and outlet blood pressure and the outlet blood flow of internal carotid artery all decreased under two kinds of coupling method. The distribution of low time average wall shear stress (TAWSS) and high oscillatory shear index (OSI) of the internal carotid artery both increased with the increase of stenosis degree under two kinds of coupling method in general. The anterior cerebral artery segment showed lower shear stress and higher OSI with bidirectional coupling in 70% stenosis, and the blood flow direction of posterior communicating artery was changed, which was significantly different from unidirectional coupling results. Conclusions At a low degree of stenosis, the result of those two kinds of coupling method were consistent in general, but there was a significant difference in 70% stenosis, and the result of bidirectional coupling was closer to physiological parameters. The research findings can be better applied to the hemodynamic study of cerebrovascular diseases.

Surgery of a Posterior Communicating Artery Aneurysm with Fetal-Type Circulation

Inadvertent occlusion of a fetal-type posterior communicating artery in aneurysm surgery could result in posterior circulation infarction and neurological morbidity. The case of a patient with an unruptured posterior communicating artery aneurysm with lateral projection and a fetal-type posterior communicating artery is presented. The utility of the carotid-oculomotor window as a surgical corridor to safely find the fetaltype posterior communicating artery is discussed.

A oclusão da artéria comunicante posterior do tipo fetal em cirurgia de aneurisma pode resultar em infarto da circulação posterior e morbidade neurológica. Apresentamos o caso de um paciente com aneurisma não roto da artéria comunicante posterior com projeção lateral e uma artéria comunicante posterior do tipo fetal. Discutimos a utilidade da janela carótida-oculomotora como um corredor cirúrgico para encontrar com segurança a artéria comunicante posterior do tipo fetal.

Blood Vessel and Intraplaque Hemorrhage Simultaneous Imaging Sequence in Evaluation of the Integrity of Willis Circle / 中国医学影像学杂志

Purpose To investigate the value of simultaneousnon-contrast angiographyand intra-plaquehemorrhage (SNAP) in assessing Willis circle integrity of the brain using three-dimensional time of flight (TOF) MRA as a reference. Materials and Methods According to the inclusion criteria, a total of 62 patients with stroke symptoms within 3 months were collected. All patients underwent head SNAP and TOF on Philips 3.0T MR scanner. TOF and SNAP were treated respectively at the Philips workstation using maximum and minimum intensity projections to generate non-enhanced MRA images which were, afterwards, interpreted using blind reading to determine the presence or absence of individual blood vessels in the circle of Willis. In order to assess the consistency of the interpretation, all images were interpreted again 2 weeks later to avoid memory bias. Finally, The consistency of the two interpretations was analyzed, and the ability of SNAP and TOF in evaluating the integrity of Willis circle was compared. In addition, for 15 patients with VISTA images, the plaque of Willis circle vascular wall was evaluated using SNAP and VISTA images to compare their evaluation ability. Results The results of the first and second interpretations of SNAP and TOF were highly consistent. The arteries with exactly the same interpretation included left anterior cerebral artery A1 (LA1), right anterior cerebral artery A1 (RA1), left posterior cerebral artery P1 (LP1) and right posterior cerebral artery P1 (RP1) (Kappa=1.000). The results in terms of left posterior communicating artery (LPCoA) (Kappa=0.926 and 0.924, respectively), right posterior communicating artery (RPCoA) (Kappa=0.931 and 0.732, respectively) and integrity (Kappa=0.815 and 0.816, respectively) were relatively consistent, while there was a relatively low consistency in terms of anterior communicating artery (ACoA) (Kappa=0.640 and 0.675, respectively). In evaluating the constituent vessels of the circle of Willis and its integrity, SNAP and TOF showed good consistency. Vessels with identical SNAP and TOF interpretations include LA1, RA1, LP1, and RP1 (Kappa=1.000). The interpretation consistency of the two imaging techniques on LPCoA (Kappa=0.852 and 0.848), RPCoA (Kappa=0.796 and 0.796, respectively), and integrity (Kappa=0.701 and 0.742, respectively) was relatively high. While the consistency of SNAP and TOF in terms of ACoA was slightly lower (Kappa=0.680 and 0.714, respectively). In assessing the plaque of Willis circle vascular wall, the evaluation results of SNAP and VISTA were consistent. Conclusion As a non-enhanced angiography technique, the magnetic resonance SNAP sequence can well evaluate the integrity of Willis circle, as well as the presence or absence of plaque on Willis circle vascular wall.

MSCT analysis of integrity of Willis circle and the correlation with aneurysm / 中国介入影像与治疗学

Objective To observe the relationship between the integrity of Willis circle and aneurysm with MSCT angiography.Methods CTA data of 580 patients with intracranial vascular lesions were retrospectively analyzed.The morphological structure of Willis circle and the occurrence of aneurysm were observed based on axial thin-layer,VR,MIP and MPR images.According to the integrity,Willis circle were divided into type Ⅰ (Willis circle complete),type Ⅱ (the anterior circulation complete but the posterior circulation incomplete),type Ⅲ (the anterior circulation incomplete but the posterior circulation complete) and type Ⅳ (both the anterior and posterior circulation incomplete) for statistical analysis.Results For the classification of Willis circle,there were 118 cases of type Ⅰ (118/580,20.34％),344 of type Ⅱ (344/580,59.31％),25 of type Ⅲ (25/580,4.31％) and 93 cases of type Ⅳ (93/580,16.03％).The incidence of Ⅰ-Ⅳtypes of Willis circle with aneurysm accounted for 16.10％ (19/118),14.83％ (51/344),32.00％ (8/25) and 23.66％ (22/93),respectively.The incidences of aneurysm in patients with different types of Willis circlewere statistically significant (x2=8.013,P=0.046).There was statistical difference of the type of Willis circle between different genders (x2=12.631,P=0.006),and the incidence of aneurysm in females was higher than that in males (25.00％ [63/252] vs 11.28％ [37/328];x2 =18.80,P＜0.025).Conclusion Most Willis circle were not complete,and incomplete Willis circle aneurysm tended to occur in females with higher aneurysm rate.

Cerebrovascular reserve in patients with acute atherosclerotic cerebral infarction and its application value in the short-term prognosis / 中华神经科杂志

Objective To assess the cerebrovascular reserve (CVR)and the relationship of CVR with the short-term prognosis in patients with acute atherosclerotic cerebral infarction.Methods A total of 106 patients with unilateral acute (within 72 h) atherosclerotic cerebral infarction (trial group) were selected from December 2016 to December 2017 in the Department of Neurology of the First People's Hospital of Hefei,which were divided into two groups including the lesion group (106 cases) and the nonlesion group (106 cases).The median score of NIHSS in patients was 4(2,5).The control group included 40 healthy controls.The cerebral blood flow reserve and pulsatility index were measured by transcranial Doppler combined with CO2 inhalation test in both the trial group and the control group.According to the rate of change of cerebral blood flow velocity (CBFV),all subjects were divided into two groups including the normal group and the impaired cerebral blood flow reserve group.The changes of CBFV were compared in the control group and the trial group,which was divided into two groups including the group with lesion side and the group with non-lesion side.To evaluate the brain structure reserve the circle of Willis in the trial group was assessed by MRA.According to the integrity of the circle of Willis anterior and posterior circulation all subjects were divided into four groups (type Ⅰ,type Ⅱ,type Ⅲ and type Ⅳ).The effect of the factors,such as diabetes,hypertension,low density lipoprotein (LDL),high density lipoprotein (HDL),smoking,and drinking history,on cerebral blood flow reserve was measured by single-factor analysis.The correlation of NIHSS scores,infarct size and volume with CVR was also measured.All patients in the trial group were treated with drugs and were followed-up for three months.The modified Rankin Scale (Mrs) was used to evaluate the prognosis of the patients.It means poor prognosis if the value of Mrs was more than three.The effects of factors,such as sex,HDL,LDL,diabetes,hypertension,smoking history,drinking history,cerebral blood flow reserve,NIHSS scores,brain structure reserve,infarct location,age,on the prognosis were measured by multivariate Logistic regression.Results The increase rate of CBFV in the lesion-side of patients with atherosclerotic cerebral infarction was 5.94％ (2.18％,10.49％),and the increase rate of pulsatility index was 10.77％ (2.21％,22.62％),which were both lower than the control group (CBFV:11.54％ (5.01％,17.96％),Z =2.547,P＜0.05);pulsatility index:48.36％ (33.93％,64.51％),Z =6.604,P ＜ 0.01).There was significant difference (x2 =4.328,P ＜ 0.05) in the distribution of diabetes,which was 2/14 in the normal group and 43.48％ (40/92) in the impaired cerebral blood flow reserve group.And in the trial group the brain structural reserve was positively correlated to the infarct volume and the NIHSS score,and the rank correlation coefficient was 0.219 and 0.238 respectively (P ＜ 0.05).The prognosis of cerebral blood flow reserve in the normal group was better than the impaired group (x2 =4.155,P ＜ 0.05),for example,the proportion of patients with good prognosis and normal CBFV was 18.84％ (13/69),the proportion of patients with good prognosis but decreased CBFV was 81.16％ (56/69),the proportion of patients with poor prognosis but normal CBFV was 2.70％ (1/37),the proportion of patients with poor prognosis and decreased CBFV was 97.30％ (36/37).The proportion of patients with type Ⅰ and type Ⅲ of the brain structure reserve was 37.68％ (26/69) and 5.80％ (4/69) respectively,whose prognosis was better (x2 =8.456,P ＜ 0.05) than patients with type Ⅱ and type Ⅳ,whose proportion was 43.48％ (30/69) and 13.04％ (9/69).Multivariate Logistic regression analysis showed that NIHSS score,age,and brain structural reserve were risk factors for poor prognosis in the trial group.Normal cerebral blood flow reserve was a protective factor for good prognosis.Conclusions CVR in patients with acute atherosclerotic cerebral infarction is significantly reduced.CVR can be used as an index to evaluate the prognosis of patients who were followed-up for three months.

Application and efficacy of induced hypertension and hypotension in carotid endarterectomy / 中华普通外科杂志

Objective To evaluate the safety and efficacy of induced hypotension and hypotension in carotid endarterectomy (CEA).Methods Data of 1 486 patients who underwent CEA in multicenters from Aug 2012 to Aug 2018 were retrospectively analyzed.After screening,a total of 1 448 patients met the inclusion criteria.Induced hypertension and hypotension was used in all thees patients.Results 87.8％ of the patients were with severe carotid stenosis.The average operative time was (51.8 ± 6.1) min,and the internal carotid artery clamping time was (11.4 ± 3.1) min.After induced hypertension,the stump pressure were higher than that before,of which 1 438 (99.3％) were greater than 50 mmHg.Monitoring of EEG oxygen saturation showed that the value of ipsilateral rSO2 was significantly lower than that of the contralateral [(56％ ± 3％) vs.(64％ ± 4％),P ＜ 0.05] before induced hypertension.After induced hypertension and clamp removal,the value of ipsilateral rSO2 was lower than that of the contralateral,but there was not significant difference (all P ＞ 0.05).Perioperative cerebral infarction occurred in 2 cases,ipsilateral cerebral hemorrhage in 1 case,contralateral cerebral hemorrhage in 1 case and myocardial infarction in 2 cases.Connclusion The technique of induced hypotension and hypotension play a temporary role in brain protection for patients undergoing CEA.This study demonstrated the safety and effectiveness of induced hypertension and hypotension technique.

The association of the circle of Willis anomaly and risk of stroke in patients with carotid artery disease / A associação de anomalia de Círculo de Willis e o risco de AVC em pacientes com doença carotídea

ABSTRACT The circle of Willis is an important collateral system that maintains perfusion to the stenotic area from the contralateral carotid and basilar artery to the region of reduced brain perfusion. The aim of the present study was to compare the circle of Willis anomaly in patients with unilateral symptomatic and asymptomatic carotid artery disease. Results In this retrospective study, we analyzed 175 patients who presented at our outpatient stroke clinic between January, 2013 and June, 2015 with either unilateral symptomatic or asymptomatic carotid artery disease, and who had had CT angiography imaging performed. Demographic properties, carotid artery stenosis and the anomaly of the circle of Willis was recorded. Conclusion There was no statistically significant difference in patients with symptomatic and asymptomatic carotid artery disease in terms of the anomaly of the circle of Willis.

RESUMO O Círculo de Willis é um importante sistema colateral que mantém a perfusão à área estenótica da carótida contralateral e da artéria basilar para a região de perfusão cerebral reduzida. O objetivo do presente estudo foi comparar a anomalia do Círculo de Willis em pacientes com doença carotídea assintomática e sintomática unilateral. Resultados Neste estudo retrospectivo, foram analisados 175 pacientes que foram à nossa clínica ambulatorial de AVC, entre janeiro de 2013 e junho de 2015, com doença carotídea assintomática ou sintomática unilateral, e que fizeram angiografia por tomografia computadorizada. Propriedades demográficas, estenose da artéria carótida e anomalia do Círculo de Willis foram registradas. Conclusão Não houve diferença estatisticamente significativa em pacientes com doença carotídea sintomática e assintomática em termos de anomalia do Círculo de Willis.

Circle of Willis variants and white matter lesions / 国际脑血管病杂志

Circle of Willis is the most important intracranial collateral circulation system,it has many types of variation.Circle of Willis variants reduce intracranial blood perfusion and increase the risks of ischemic cerebrovascular diseases and white matter lesions.White matter lesions are white matter damage caused by a variety of causes.With the wide application of neuroimaging technology,the detection rate of white matter lesions is significantly higher,and it is closely associated with the ischemic cerebrovascular disease.This article reviews the correlation between circle of Willis variants and white matter lesions.

MRA Classification of the Artery Structures at the Base of the Brain / 中国医科大学学报

Objective To observe and classify the structure of the circle of Willis by using magnetic resonance angiographic(MRA)method. Methods A total of 2104 MRA head images from October 2013 to May 2015 in Shenyang Weikang Hospital was retrospective analyzed ,and the structure was classified by anterior circle or posterior circle according to the actual situation of the cerebral basilar artery. Results According to the origin of anterior cerebral artery and whether there was anterior communicating artery or not ,anterior circle was classified into three types:type Ⅰ,type Ⅱ and type Ⅲ. Type Ⅱ was classified into two subtypes,namely,type ⅡR and type ⅡL. Posterior circle,on the basis of whether there was posterior communicating artery or not,was classified into three types,which were type Ⅰ,type Ⅱ and type Ⅲ. According to the origin of posterior cerebral artery,type Ⅰ was classified into four subtypes,including type ⅠB,type ⅠC,type ⅠRC and type ⅠLC;type Ⅱ was classified into eight subtypes,including type ⅡBR,type ⅡBL,type ⅡCR,type ⅡCL,type ⅡRCR,type ⅡRCL,type ⅡLCR and type ⅡLCL;type Ⅲ was classified into four subtypes,including type ⅢB,type ⅢC,type ⅢRC,type ⅢLC. Conclusion There is a correlation among the different types of cerebral basi-lar artery,and each type of artery has their own sources of blood supply and the traits of communication compensation. When the anterior circle and posterior circle were both type Ⅲ,the complete ring structure of cerebral basilar artery,namely the circle of Willis,was formed. The existing rate of the circle of Willis was about 10.7%. Understanding of the differences among the individual types of arteries has great significance to the prevention and treatment of the cerebrovascular disease.

Métodos de avaliação do olfato em pacientes vítimas de hemorragia subaracnóidea: revisão sistemática / Methods of evaluation of smell in victims of subarachnoid hemorrhage patients: a systematic review

RESUMO Objetivos: Revisar de forma sistemática os métodos para avaliação do olfato em vítimas de hemorragia subaracnóidea aneurismática, e identificar as alterações encontradas com a utilização desses métodos. Estratégia de pesquisa: A pesquisa bibliográfica foi realizada na plataforma de busca PubMed e nas bases de dados Web of Science, Scopus, PsycINFO, CINAHL e ScienceDirect, tendo a busca de dados ocorrida em agosto e setembro de 2014. Critérios de seleção: Artigos originais publicados em qualquer língua que abordassem as alterações de olfato na hemorragia subaracnóidea aneurismática, com objetivo de avaliar essa função através de métodos específicos. Foram excluídos estudos de revisão; estudos de caso; capítulos de livro; editoriais e estudos que abordassem a hemorragia subaracnóidea não aneurismática. Análise dos dados: Foram consideradas como variáveis na análise dos dados: autor/ano, país, amostra/idade, tratamento, método utilizado, momento da avaliação do olfato e resultados. Resultados: A busca de artigos resultou em 1.763 artigos, desses, 9 artigos originais foram selecionados para esta revisão. Foi observado que todos os artigos foram desenvolvidos em países europeus e asiáticos e na avaliação do olfato utilizou-se desde testes padronizados e não padronizados a questionários, cujos objetivos variaram entre avaliar o olfato antes e/ou após o tratamento cirúrgico nessa população. Conclusão: Foi observada heterogeneidade nos métodos utilizados para avaliação do olfato na hemorragia subaracnóidea aneurismática, como também no momento selecionado para aplicação das avaliações. Além disso, os estudos evidenciaram a existência de déficit olfatório nos pacientes, e a relação entre o tratamento cirúrgico e a disfunção olfatória.

ABSTRACT Purpose: To systematically review the methods for evaluation of smell in aneurysmal subarachnoid hemorrhage victims and to identify the changes found with the use of these methods. Research strategy: The literature search was performed in PubMed search platform and in the databases Web of Science, Scopus, PsycINFO, CINAHL, and ScienceDirect in August and September 2014. Selection criteria: Original articles published in any language, which addressed smell changes in aneurysmal subarachnoid hemorrhage and addressed to evaluate this function through specific methods were included. Review studies, case studies, book chapters, editorial, and studies that address the nonaneurysmal subarachnoid hemorrhage were excluded. Data analysis: The following variables were considered in data analysis: author/year, country, sample/age, treatment, method, the moment of smell evaluation, and results. Results: The search for articles resulted in 1,763 articles, of which, 9 original articles were selected for this review. It was observed that all articles were from European and Asian countries. Standardized and nonstandardized tests and questionnaires were used in olfactory assessment, and the goals ranged from assessing the smell before and/or after surgery in this population. Conclusion: Heterogeneity was observed in the methods used to evaluate the smell in aneurysmal subarachnoid hemorrhage and in the methods selected for application of evaluations. In addition, studies have demonstrated the existence of olfactory deficits in patients and the relationship between surgery and olfactory dysfunction.

Clinical study of the relationship between Willis arterial loop variation and intracranial aneurysms / 中国医师杂志

Objective To explore the relationship between the changes of the cerebral arterial circle of Willis and the occurrence of intracranial aneurysms in the diagnosis of digital angiography.Methods From December 2014 to January 2014,144 cases of intracranial aneurysms were treated in the First Affiliated Hospital of Luzhou Medical University.According to the location of the aneurysm of all patients,the patients were divided into the anterior communicating artery and the posterior communicating artery aneurysms.The relationship between two groups of patients was compared by the sex,age,and the length of the intracranial aneurysms.The relationship was analyzed between the Willis ring and the intracranial aneurysms.The sensitivity and specificity were compared with the surgical results.Results A total of 144 cases of intracranial aneurysms were detected by digital angiography,68 patients in anterior communicating artery aneurysms,and posterior communicating artery aneurysm in 76 cases.There were no significant differences in sex distribution,age distribution,and length of tumor in the patients with anterior communicating artery aneurysms and the patients with a group of patients with a posterior communicating artery aneurysm.The anterior communicating artery aneurysm group,A1 segment of slender or absence rate was up to 79.41％,and communicating artery aneurysm group A1 segment of slender or absence rate was only 52.63％,two groups were compared with statistical significance (P ＜ 0.05).In the anterior communicating artery,the posterior cerebral artery was 63.24％,and the right and left (unilateral) embryonic cerebral artery was 59.21％ in the middle cerebral artery.There was no significant difference in the sensitivity and specificity of CT angiography (CTA) test results between two groups(P ＞ 0.05).Conclusions Digital angiography can be more accurate in the diagnosis of intracranial aneurysms.Anterior communicating artery aneurysm occurrence is closely related to A1 segment of slender,and absent and bilateral embryo brain artery.Communicating artery aneurysms is more closely related to unilateral embryonic brain artery.

Role of balloon occlusion test in the treatment of permanent internal carotid artery occlusion / 局解手术学杂志

Objective To investigate the relation between the balloon occlusion test ( BOT) and the anatomy of the circle of Willis ( CW) , and to explore the role of balloon occlusion test in the treatment of internal carotid artery permanent occlusion. Methods Selected the clinical data of 49 patients (52 sides) who had BOT in our hospital from October 2009 to June 2015,and analyzed the relationship be-tween the occurrence rate of anterior communicating artery ( AcoA) / posterior communicating artery ( PcoA) and the positive rate of BOT retrospectively. Results The occurrence rate of the AcoA was 97. 9%, and the occurrence rate of PcoA in one side was 82. 7%. Negative rate BOT accounted for 92. 3% and AcoA occurred in all, while the positive rate accounted for 7. 7%, including 2 cases of right superior ar-teria cerebri anterior combined with ipsilateral PcoAs absence, 1 case of left superior arteria cerebri anterior combined with ipsilateral PcoAs absence, and 1 case of AcoA and PcoAs absence. Conclusion Before the permanent occlusion of the internal carotid artery, it’ s necessary to clarify the redistribution of the compensatory way of blood flow in the AcoA-absent cases. Implementing permanent occlusion for cases with complete circle of Willis would cause less ischemic risk.

Differentiating Carotid Terminus Occlusions into Two Distinct Populations Based on Willisian Collateral Status / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: The outcomes of acute internal carotid artery (ICA) terminus occlusions are poor. We classified ICA terminus occlusions into 2 groups according to the occlusion pattern of the circle of Willis and hypothesized that clinical outcomes would significantly differ between them. METHODS: Consecutive patients with acute ICA terminus occlusions evaluated by baseline computed tomographic angiography were enrolled. We investigated the occlusion patterns in the circle of Willis, retrospectively classified patients into simple ICA terminus occlusion (STO; with good Willisian collaterals from neighboring cerebral circulation) and complex ICA terminus occlusion (CTO; with one or more of A2 anterior cerebral artery, fetal posterior cerebral artery occlusion, or hypoplastic/absent contralateral A1; or with poor collaterals from anterior communicating artery) groups, and compared their baseline characteristics and outcomes. RESULTS: The STO group (n=58) showed smaller infarct volumes at 72 hours than the CTO group (n=34) (median, 81 mL [interquartile range, 38-192] vs. 414 mL [193-540], P<0.001) and more favorable outcomes (3-month modified Rankin Scale 0-3, 44.8% vs. 8.8%, P<0.001; 3-month mortality, 24.1% vs. 67.6%, P<0.001). In multivariable analyses, STO remained an independent predictor for favorable outcomes (odds ratio 6.1, P=0.010). CONCLUSIONS: Favorable outcomes in STO group suggested that the outcomes of acute ICA terminus occlusions depend on Willisian collateral status. Documenting the subtypes on computed tomographic angiography would help predict patient outcome.

Investigation of morphologic variations of circle of Willis using 3D-TOF MR angiography in medical examination and its importance / 中国医学装备

Objective:To investigate morphologic variations of circle of Willis in healthy adults using 3D-TOF MR angiography in medical examination and its clinical significance. Methods:To analyze the characteristics of the vascular morphology in 442 healthy adults of head 3D-TOF MRA in the post processing workstation retrospectively. Results: All the 442 cases, the variations of circle of Willis were found in 152,the variations of A1, A2, ACoA, PCoA, P1 were found in 76(50.00%), 23(15.13%), 7(4.61%), 101(66.45%), 68(44.74%). The variation of A1 was positively correlated with PCoA, the variation of PCoA in female was more than in male. Conclusion:Medical examination-3D-TOF MRA has important value to display morphologic variations of circle of Willis in healthy adults, which can provide important guide value in the clinical.