[Transient global amnesia - benign memory blackout]. / Transiente globale Amnesie ­ gutartiger "Blackout" im Gedächtnis.

Transient global amnesia (TGA) is a typical clinical syndrome characterized by acute, predominantly anterograde amnesia. New epidemiological data assume a significantly higher annual incidence than previously assumed, namely around 15 cases per 100,000 people. Those affected, usually over the age of 50, cannot remember new memory content for longer than 30-180 seconds and therefore ask repetitive questions about current events. All other cognitive functions are unimpaired, and everything previously learnt, e.g. driving or cooking, can be carried out. The episodes are self-limiting and by definition subside within 24 hours. At least 10% of those affected will experience 1-5 recurrences in the future. The punctate lesions in the hippocampus, which are found on MRI in at least 50% of patients after 24-72 hours, are distributed 2/3 unilaterally and 1/3 bilaterally. Using 7 Tesla MRI the frequency of detected lesions increases to 90% compared to 50% with 1.5 or 3 Tesla. Beyond the punctiform hippocampal lesions, other memory-related network disorders, including the default network, are also suggested to be involved in the pathomechanism of TGA. TGA etiology and pathophysiology are not known in detail. Vascular, migraine-like, epilepsy-like, and psychogenic mechanisms are discussed. Triggers of the episodes are often physical exertion with a Valsalva character. Management is aimed at identifying the syndrome based on the typical clinical presentation and ruling out possible differential diagnoses with similar symptoms. During the TGA, the usually anxious relatives should be reassured of the benign and inconsequential nature of the episode.

Amnesia global transitoria: una entidad infrecuente pero presente en Pediatría / Transient global amnesia: an infrequent entity but present in Pediatrics

Introducción: La amnesia global transitoria es una entidad caracterizada por la aparición súbita de amnesia anterógrada con amnesia retrógrada variable, conservando intacta la memoria inmediata. No asocia otros déficits neurológicos. La recuperación es progresiva en pocas horas, habitualmente menos de 12, aunque suele persistir amnesia del episodio y presentar posteriormente cefalea leve. Caso clínico. Niño de 10 años, sin antecedentes de interés, que consulta en Urgencias por aparición brusca de amnesia retrógrada de las últimas 48 horas, así como incapacidad para la fijación de nueva información. Se mostraba ansioso y desorientado, y repetía la misma pregunta varias veces. La exploración neurológica por lo demás era estrictamente normal y negaba cefalea u otra sintomatología asociada. No antecedente de traumatismo craneoencefálico. Se realiza analítica sanguínea y gasometría venosa, sin alteraciones significativas; tóxicos en orina, negativos; TAC cerebral que descarta patología intracraneal aguda y punción lumbar, que es normal. Ingresa en planta de hospitalización con evolución favorable, con cese espontáneo de la clínica a las 8 horas, permaneciendo amnesia del episodio, con resto de la memoria conservada. Comentarios. La fisiopatología de la amnesia global transitoria no está del todo aclarada, aunque hay trabajos que sugieren un origen vascular de la misma, produciéndose durante estos episodios una hipoperfusión del lóbulo temporal medial. Es una entidad típica de adultos de mediana edad y ancianos siendo excepcional en pediatría. Sin embargo, debemos considerar este diagnóstico ante niños con clínica típica, normalidad de la neuroimagen y resolución espontánea de los síntomas.(AU)

Introduction: Transient global amnesia is an entity characterized by the sudden onset of anterograde amnesia with variable retrograde amnesia, preserving immediate memory intact. It is not associated with other neurological deficits. Recovery is progressive in a few hours, usually less than 12 hours, although amnesia of the episode usually persists and later presents mild headache. Case report. A 10-year-old boy, with no previous history of interest, consulted the emergency department for sudden onset of retrograde amnesia of the last 48 hours, as well as inability to fix new information. He was anxious and disoriented and repeated the same question several times. The neurological examination was otherwise strictly normal, and he denied headache or other associated symptoms. There was no history of cranioencephalic trauma. Blood analysis and venous blood gas analysis were performed, with no significant alterations; urine toxins were negative; brain CAT scan ruled out acute intracranial pathology and lumbar puncture was normal. She was admitted to the hospital ward with favorable evolution, with spontaneous cessation of the clinical symptoms after 8 hours, remaining amnesia of the episode, with the rest of the memory preserved. Comments. The pathophysiology of transient global amnesia has not been fully clarified, although some studies suggest a vascular origin, with hypoperfusion of the medial temporal lobe occurring during these episodes. It is a typical entity of middle-aged and elderly adults, being exceptional in pediatrics. However, we should consider this diagnosis in children with typical clinical symptoms, normal neuroimaging and spontaneous resolution of symptoms.(AU)

Amnésia global transitória: epidemiologia, fisiopatologia, clínica e terapêutica / Global transient amnesia: epidemiology, pathophysiology, clinical features and therapeutics

A amnésia global transitória (AGT) é um quadro súbito de amnésia global, não acompanhada de outros déficits neurológicos, com duração de duas a 24 horas e cuja recuperação se dá espontaneamente. A incidência na população geral está estimada em 5-10 casos/100.000 pessoas/ano. Diferentes mecanismos fisiopatológicos, como fatores vasculares ou epiléticos, têm sido propostos para explicar a AGT, sendo consensual que haja acometimento transitório de regiões do hipocampo e do giro para-hipocampal. Além da amnésia anterógrada acompanhada por amnésia retrógrada, o paciente apresenta desorientação (tempo/espaço), estando preservadas outras habilidades cognitivas, como memória semântica e capacidades visuo-construtivas. Esses déficits tendem a remitir após 24h, sendo o prognóstico favorável na maioria dos casos. O diagnóstico diferencial de AGT é amplo e diversas condições clínicas, como eventos cérebro-vasculares, epilepsias, infecções e intoxicações podem mimetizá-lo, de modo que uma investigação clínica cuidadosa é imperativa. As recorrências não são frequentes nos quadros típicos. A AGT não requer tratamento específico, mas devem ser tratados fatores de risco cardiovascular eventualmente identificados durante a propedêutica de AGT. O clínico deve esclarecer o paciente a respeito do caráter benigno da AGT. Estudos com seguimento longitudinal dos pacientes são necessários para maior compreensão dos mecanismos fisiopatológicos da AGT e para melhor compreensão clínica e neuro- biológica dos déficits cognitivos apresentados por esses pacientes.

Global transient amnesia (GTA) is a clinical syndrome characterized by the sudden onset of anterograde and retrograde amnesia, without permanent neurological deficits, and which presents complete remission spontaneously within 2 to 24 hours. The incidence of GTA in the general population ranges from 5 to 10 cases per 100.000 individuals/ year. Different pathophysiological mechanisms have been proposed for GTA, such as vascular or epileptic factors, and it is consensual that there is transitory involvement of hippocampal and parahippocampal gyri in this condition. In addition to anterograde and retrograde amnesia, GTA patients typically present time-space disorientation, with the preservation of other cognitive abilities, such as semantic memory and visuoconstructive capacities. The differential diagnosis includes stroke, epilepsy, infections and intoxication, and a careful clinical investigation is essential to establish the GTA diagnosis. Recurrence is uncommon in typical cases and, in general, no specific treatment is required. However, clinical investigation of GTA may eventually disclose cardiovascular risk factors; these factors should be treated when identified. GTA is considered a benign condition, with good clinical and cognitive prognostics in most of the cases. More studies are needed to advance the current knowledge on the pathophysiology and on the neural basis of the transitory cognitive impairment observed in GTA.

Persistência de imagem de hiperintensidade no hipocampo após episódio de amnésia global transitória / Persistence of hyperintensity image in the hippocampus after an episode of transient global amnesia

A patogenia da amnésia global transitória (AGT) continua obscura. Estudos recentes demonstraram que, em alguns pacientes, a sequência de difusão (DWI) da ressonância magnética pode revelar apresença de sinal pequeno e pontual hipersinal no hipocampo, após a fase aguda do episódio. Esse sinal é principalmente visualizado nas primeiras 6 horas do início do evento, sendo 114 horas o tempo máximo que foi registrado até o momento. Estamos apresentando um caso em que essa imagem persistiu por 11 dias após o episódio. Discutem-se as conhecidas causas, as teorias da patogenia da AGT e a possível conexão entre um efeito vascular e a depressão alastrante, como relatada na enxaqueca com aura.

The pathogenesis of transient global amnesia (TGA) remains obscure.Recent studies revealed that small and punctate signal on diffusion-weighted imaging (DWI) in the hippocampus after the post-acute phase. This signal is mainly seen in the first 6 hours of the onset of the event, and so far the maximum time registered was 114 hours. We present one case where this image persisted for 11 days after the episode. Known causes, theories on pathogenesis of TGA and a possible relation between a vascular mechanism and the spreading depression, as reported in migraine with aura, are discussed.

Higher Lesion Detection by 3.0T MRI in Patient with Transient Global Amnesia

PURPOSE: Transient global amnesia (TGA) patients were retrospectively reviewed to determine the usefulness of high-field strength MRI in detecting probable ischemic lesions in TGA. MATERIALS AND METHODS: We investigated the lesion detection rate in patients with TGA using 1.5T and 3.0T MRI. Acute probable ischemic lesions were defined as regions of high-signal intensity in diffusion weighted image with corresponding low-signal intensity in apparent diffusion coefficient map. RESULTS: 3.0T MRI showed 11 out of 32 patients with probable ischemic lesions in the hippocampus with mean lesion size of 2.8 +/- 0.6 mm, whereas 1.5T MRI detected no lesion in any of 11 patients. There were no significant differences in clinical characteristics between the groups of 1.5 and 3.0T MRI. CONCLUSION: High-field strength MRI has a higher detection rate of probable ischemic lesions than low-field strength MRI in patients with TGA.

Utilidad de la electroencefalografía en la valoración de la amnesia global transitoria / Usefulness of electroencephalograms in evaluating transient global amnesia

Introducción. La amnesia global transitoria (AGT) es un cuadro clínico perfectamente definido, pero hoy día aún representa una incógnita desde el punto de vista etiológico. Las tres teorías más aceptadas sugieren un origen vascular del episodio, una relación con la fisiopatología de la migraña o un carácter epileptiforme. Objetivo. Analizar si existe algún patrón electroencefalográfico que se repita de manera consistente en una serie de electroencefalogramas (EEG) de pacientes con AGT. Pacientes y métodos. Análisis retrospectivo de una muestra de 345 pacientes remitidos para la realización de EEG tras un episodio de AGT. Resultados. En casi el 20% de los EEG se encontró algún hallazgo fuera de la normalidad, si bien la mayor parte de ellos (64%) era de escaso significado patológico. Del 26% restante cabe destacar la presencia de dos pacientes con descargas electroencefalográficas rítmicas subclínicas del adulto (patrón de significado incierto que previamente ya se ha asociado con AGT). Conclusiones. Existe un porcentaje no despreciable de pacientes con AGT y alteraciones en el EEG, si bien la mayor parte de ellas es de escaso significado patológico o atribuible a otra patología de base. No hemos sido capaces de identificar ningún patrón que se repita de manera consistente. Nuestros resultados sugieren que el EEG es una prueba con bajo rendimiento diagnóstico en esta patología y que habría que plantearse la necesidad de realizarla sistemáticamente ante una AGT (AU)

Introduction. Transient global amnesia (TGA) is a perfectly well defined clinical picture, but nevertheless even today its aetiology remains unknown. The three most widely accepted theories suggest it has a vascular origin, it is related with the pathophysiology of migraine or it is of an epileptiform nature. Aim. To analyse whether there is an electroencephalographic pattern that is consistently repeated in a series of electroencephalograms (EEG) carried out on patients with TGA. Patients and methods. The study consists in a retrospective analysis of a sample of 345 patients referred to have an EEG after an episode of TGA. Results. In almost 20% of the EEGs something that could be considered abnormal was found, although most of these findings (64%) were of little pathological significance. Of the remaining 26%, attention should be drawn to the cases of two patients with subclinical rhythmic electroencephalogram discharges of adults (a pattern with a meaning that is not altogether clear and which has previously been associated with TGA). Conclusions. A considerable percentage of patients have TGA and EEG alterations, although most of them are of scarce pathological significance or can be attributed to some other underlying condition. We have not succeeded in identifying any pattern that is consistently repeated. Our results suggest that the EEG is a test with low diagnostic effectiveness in this pathology and it is necessary to reconsider the need to systematically perform such tests in suspected cases of TGA (AU)

Memoria y metamemoria durante la amnesia global transitoria: estudio comparativo sobre su evolución a largo plazo / Memory and metamemory during transient global amnesia: a comparative study about long-term follow up

Introducción. Los criterios diagnósticos de la amnesia global transitoria (AGT) establecen que el funcionamiento de la memoria se debe restablecer, como máximo, en 24 horas. Sin embargo, existen datos contradictorios sobre si aparecen secuelas a largo plazo. Además, no está claro qué herramienta es la más adecuada para controlar la evolución de estos pacientes. Objetivos. Evaluar la afectación de la memoria episódica de los pacientes con AGT durante el episodio amnésico y a los 7, 30 y 90 días después, con la tarea de recuerdo libre y con el test minimental, y estudiar la metamemoria de estos pacientes. Sujetos y métodos. Se han evaluado 17 pacientes con AGT y 17 voluntarios igualados en edad, sexo y nivel educativo con el grupo de pacientes. Se ha realizado un estudio longitudinal (cuatro evaluaciones) factorial (con el grupo de pacientes y el grupo control). Resultados. Durante la AGT, los pacientes muestran afectación de la memoria episódica tanto utilizando la tarea de recuerdo libre como el test minimental. Sin embargo, sólo la prueba de recuerdo libre detecta una mejoría a lo largo del tiempo y una puntuación alterada tres meses después. Por otra parte, se ha evidenciado que la metamemoria de estos pacientes es poco precisa. Conclusiones. Tanto la tarea de recuerdo libre como el test minimental detectan alteración durante la AGT, pero sólo la primera es una prueba sensible a la alteración de la memoria a largo plazo asociada a este tipo de amnesia (AU)

Introduction. Diagnostic criteria of transient global amnesia (TGA) establishes that memory functioning has to be recovered in 24 hours. However, there are contradictory data about the existence of long-term sequelae. Furthermore, there is no consensus about which is the most suitable tool in order to use in the assessment of the follow up of these patients. Aims. To assess episodic memory of TGA patients during amnesic episode and 7, 30 and 90 days after with free recall and Mini-Mental tasks. Moreover, it has been measured patient’s metamemory. Subjects and methods. 17 TGA patients and 17 healthy volunteers, matched by age, sex, and educational level were assessed. A longitudinal (four assessments) and factorial (patients and control group) study was carried out. Results. During TGA, free recall and Mini-Mental tasks were significantly affected. However, only free recall task showedimprovement along time and impairment after three months. It has been also detected that metamemory of TGA patients is imprecise. Conclusions. Comparing with control group, both free recall and Mini-Mental tasks have significant lower levels during TGA, but only the first one is sensitive enough to show long-term disturbance associated with this amnesia (AU)

Estudio de shunt derecha-izquierda en la amnesia global transitoria / study of right-left shunt in transient global amnesia

Introducción: La amnesia global transitoria (AGT) es una entidad de etiopatogenia incierta. En recientes estudios se cita la posible asociación entre la AGT y el shunt derechaizquierda (SDI). Por ello estudiamos la presencia de SDI en una serie de pacientes con AGT de nuestra población y la comparamos con otra población de pacientes con ataque isquémico transitorio (AIT). Pacientes y métodos: Recogimos de forma consecutiva 66 pacientes con AGT en los que se realizó un estudio de SDI mediante Doppler transcraneal. Comparamos las características clínicas del episodio, los factores de riesgo vascular, el antecedente de migraña, la recurrencia de AGT y la neuroimagen entre las AGT con y sin SDI. Comparamos la prevalencia de SDI con la de una serie de 59 casos de AIT de origen indeterminado. Resultados: En el grupo de AGT la prevalencia de SDI fue del 21,2%. La presencia de SDI se asoció con el antecedente de migraña (el 40 frente al 13%; p = 0,014) y una maniobra de Valsalva como factor desencadenante (el 50 frente al 14,5%; p = 0,022). Se observó una mayor frecuencia de SDI en el grupo de AIT (el 55,9 frente al 21,2%; p < 0,001). Conclusiones: La prevalencia de SDI en los pacientes con AGT es similar a la descrita en la población general, pero significativamente inferior a su prevalencia en aquellos con AIT de origen indeterminado. La asociación con una maniobra de Valsalva como desencadenante del episodio en las AGT con SDI podría implicar un mecanismo etiopatogénico en este subgrupo (AU)

Introduction: Transient global amnesia (TGA) is a disorder of unknown aetiology. In recent studies, TGA was associated with a right to left shunt (RLS). We studied the presence of the RLS in patients with TGA and we compared this series with patients who had suffered a transient ischaemic attack (TIA). Patients and methods: We included 66 consecutive TGA patients. In these patients a transcranial Doppler was performed to determine the presence of a RLS. We collected data on the TGA episode, vascular risk factors, migraine history, recurrence of TGA and neuroimaging in patients with and without RLS. We compared the prevalence of the RLS in TGA series with 59 patients with TIA. Results: The prevalence of RLS was 21.2% in patients with TGA. The RLS was associated with the migraine history (40% versus 13%; p = 0.014) and a Valsalva manoeuvre as a triggering factor (50% versus 14.5%; p = 0.022). A greater prevalence of RLS was detected in patients with TIA (55.9% versus 21.2%; p < 0.001). Conclusions: The RLS prevalence in TGA patients is similar to the general population but significantly lower than the prevalence in TIA patients. The association with a Valsalva manoeuvre as a precipitating factor in the TGA patients with RLS could play a role in the aetiopathogenesis of the TGA (AU)

Amnesia topográfica transitoria: descripción de una serie de ocho casos / Transient topographical amnesia: a description of a series of eight cases

Introducción. La afectación de la memoria, en concreto la orientación espacial, está presente en patologías como la demencia, accidentes cerebrovasculares o traumatismos craneoencefálicos. Más raramente ocurre de forma transitoria en personas sanas sin daño cerebral evidente, denominándose amnesia topográfica transitoria (ATT). El objetivo de este trabajo es describir una serie de ocho casos de ATT valorados en una consulta de neurología. Casos clínicos. Serie de ocho pacientes diagnosticados de ATT entre los años 2002-2008. Como criterios de inclusión, seconsideraron aquéllos que habían presentado al menos un episodio de desorientación espacial episódica sin pérdida de memoria ni conciencia, pudiendo describir los eventos ocurridos, en ausencia de deterioro cognitivo previo y con exploración neurológica normal. Las características demográficas fueron: predominio de sexo femenino (75%) y edad media de 69,13 ± 8,79 años. El número medio de episodios fue de 1,75 (rango: 1-3), con una duración media de 24,5 minutos. Tres de los ocho pacientes asociaban factores de riesgo vascular. Los ocho pacientes tenían estudios de neuroimagen donde no se observaron hallazgos de interés, salvo un caso con un área porencefálica frontal bilateral antigua a un traumatismo craneoencefálico. Se realizó tomografía simple por emisión de fotón único cerebral y ecografía Doppler a dos pacientes, con resultados normales, así como electroencefalograma, que fue también normal. Hubo un seguimiento a todos los pacientes, sin observarse ningún cambio clínico, salvo un paciente que desarrolló demencia a los seis años del episodio de amnesia. Conclusiones. La ATT se trata posiblemente de una entidad infradiagnosticada, que creemos que debe incluirse en el diagnóstico diferencial de pacientes remitidos por sospecha de deterioro cognitivo (AU)

Introduction. Impaired memory, and more particularly spatial orientation, occurs in pathologies such as dementia, cerebrovascular accidents or traumatic brain injuries. Less frequently it also appears as a transient disorder in healthy people with no apparent brain damage, in which case it is known as transient topographical amnesia (TTA). The aim of this work is to report on a series of eight cases of TTA that were evaluated in a neurology unit. Case reports. We study the cases of eight patients diagnosed with TTA over the period 2002-2008. Patients were considered to fulfil eligibility criteria if they had presented at least one episode of spatial disorientation, with no loss of memory or consciousness, and were able to describe the events that had taken place, without any previous cognitive impairment and with a normal neurological examination. The demographic characteristics taken into account in the study were: predominance of females (75%) and a mean age of 69.13 ± 8.79 years. The mean number of episodes was 1.75 (range: 1-3), which lasted an average of 24.5 minutes. Three of the eight patients had associated vascular risk factors. Neuroimaging studies did not reveal any relevant findings in any of the eight patients, except one case of a bilateral frontal porencephalic area resulting from a traumatic brain injury suffered in the past. Simple single-photon emission tomography and Doppler ultrasound imaging scans of the brain, as well as an electroencephalogram, were performed on two patients, the results being normal in all cases. Follow-ups were performed on all the patients, without any kind clinical change being observed, except for one patient who developed dementia at six years after the episode of amnesia. Conclusions. TTA is possibly an underdiagnosed condition which we believe should be included in the differential diagnosis of patients who are referred owing to suspected cognitive impairment (AU)

La amnesia global transitoria: entidad infrecuente en la infancia / Transient global amnesia: an uncommon disorder in childhood

Introducción: La amnesia global transitoria (AGT) es un cuadro de presentación súbita caracterizado por una intensa amnesia anterógrada y una amnesia retrógada variable. La memoria inmediata está conservada y el resto de la exploración neurológica es normal. La recuperación es progresiva en pocas horas. Suele presentarse en pacientes adultos de mediana edad y en ancianos. Caso clínico: Niña de 9 años de edad que presenta una amnesia anterógrada de inicio brusco, con memoria inmediata conservada y algún trastorno de la memoria retrógada, asociados a cefalea de intensidad leve. La exploración neurológica es normal. El episodio cede de forma espontánea en unas 4 horas. Posteriormente, la paciente presenta una cefalea leve y una amnesia del episodio. Se realiza una tomografía computarizada craneal, que es normal, por lo que el cuadro se orienta como AGT. Discusión: La clínica descrita es característica de la AGT. La aparición de este cuadro suele ser espontánea, aunque puede existir un factor desencadenante. Se ha postulado que podría deberse a un fenómeno vascular amplio con isquemia transitoria del territorio de la vertebrobasilar, o a un fenómeno epiléptico o migrañoso. La migraña confusional aguda, típica de la infancia, tiene manifestaciones clínicas similares a las de la AGT. El diagnóstico de este proceso es clínico. Tiene un excelente pronóstico, con poca tendencia a la recidiva. Dada la presentación poco habitual en la edad pediátrica, en nuestro caso se realizó una prueba de imagen para descartar un accidente cerebrovascular. La clínica típica y la normalidad de las pruebas de imagen deben hacernos considerar este diagnóstico también en la edad pediátrica

Introduction: Transient global amnesia (TGA) is a clinical condition characterized by sudden loss of anterograde memory and a varying degree of retrogade amnesia. Immediate memory is preserved and the neurological examination is normal. The memory deficit resolves within a few hours. This condition is frequent in middle-aged or elderly patients. Case report: A 9-year-old girl developed sudden anterograde amnesia with preserved immediate memory and a certain degree of retrogade memory deficit, associated with a mild headache. The neurological examination was normal. The clinical condition resolved spontaneously in 4 hours. The patient was left with a mild headache and no memory of the attack. As the brain computed tomographic (CT) scan was normal, the clinical condition suggested a case of TGA. Discussion: The clinical features reported here are characteristic of TGA. This neurological disorder appears spontaneously, but several precipitating factors may exist. The pathogenetic hypotheses include a vascular etiology with transient vertebrobasilar ischemia, an epileptic phenomenon or a migraine-related event. Acute confusional migraine, typical of childhood, presents with clinical manifestations similar to TGA. The diagnosis of this process is based on clinical findings. It has an excellent prognosis and little tendency to recur. Given the fact that TGA is not frequent in childhood, we performed a CT scan to rule out the possibility of a cerebral ischemic attack. The presence of the typical clinical symptoms and a normal neuroimaging study should lead us to consider this diagnosis in childhood as well

Causas vasculares de amnesia global transitoria / Vascular causes of transient global amnesia

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La policitemia como factor predisponente de amnesia global transitoria / Policithaemia as a ready factor of transitory global amnesia

La amnesia global transitoria (AGT) es un trastorno de memoria anterógrada de inicio brusco y de una duración inferior a 24 h que se ha relacionado con causas isquémicas, comiciales y migrañosas. Por otro lado, la policitemia está clasificada como un trastorno protrombótico que puede producir múltiples manifestaciones en el sistema nervioso central, desde ictus hasta trastornos psiquiátricos de tipo ansioso, y todos relacionados con la hipoperfusión cerebral secundaria a la hiperviscosidad. Presentamos dos pacientes que presentaron un episodio de amnesia global transitoria y que tenían una policitemia previa; además, en uno de los casos se encontró un hemangioblastoma cerebeloso. Hay numerosos casos en la literatura de lesiones intracraneales diagnosticadas a raíz de un episodio de AGT; sin embargo, no se ha descrito la relación entre la policitemia y la AGT. En la amnesia global transitoria se ha llegado a constatar una hipoperfusión de las regiones temporales y esto puede ser un mecanismo desencadenante; planteamos al posibilidad de que la policitemia sea un trastorno protrombótico que predisponga a padecer la amnesia global transitoria

Transitory global amnesia (TGA) is an upheaval where the patient has anterograde memory lost of abrupt beginning and an inferior duration to 24 h, that has been related to ischaemic, epileptogenic and migranous ethiology. On the other hand polycythaemia is classified like a prothrombotic disorder that can produce manifold manifestations in the central nervous system, from strokes to psychiatric disturbances of anxious type, and all related to the secondary cerebral hipoperfusión due to hyperviscosity. Two patients, who had a prevous diagnostic of polycythaemia suffered an episode of TGA, in addition in one of the two cases a cerebellar hemangioblastoma was found. There are numerous cases reported of brain tumors and other CNS findings diagnosed as a result of an episode of TGA, nevertheless on has not described to the relation between polycythaemia and the TGA. In the TGA a hipoperfusion of the temporal brain hemisphere has been documented and this can be a leading mechanism, so we propose that polycythaemia could ready to suffer a TGA

Estudio de los factores de riesgo en la amnesia global transitoria y su diferenciación del accidente isquémico transitorio / A study of the risk factors in transient global amnesia and its differentiation from a transient ischemic attack

Introduction. Transient global amnesia (TGA) is a clinical condition that has been described in many studies, but its pathophysiology is not fully understood. In recent years the theory of valvular insufficiency in the jugular vein has been added to the classical hypotheses that link it to migraine, to epilepsy and –the most widely accepted– to transient ischemic attacks (TIA), although the real origin of the condition has still not been determined. Patients and methods. In a retrospective study we compared 131 patients diagnosed with TGA between 1993 and 2004 with 262 patients who were diagnosed as having TIA over the same period. Results. Mean age was 65.94 years in TGA versus 71.11 years in the case of TIA. There was a higher rate of arterial hypertension among the patients with TGA and diabetes mellitus was more frequent among those with TIA (p < 0.05 in both cases). Emboligenic heart disease was scarce among patients with TGA. The number of patients with a history of ischaemic heart disease and a history and the development of cerebrovascular diseases was greater among those with TIA than in cases of TGA (p < 0.05). The TGA recurrence rate was 12%. The percentage of pathological findings in the CAT brain scan was higher in patients with TIA (p < 0.05). There are no significant differences between patients with TGA and TIAas far as treatment on hospital discharge is concerned. Conclusions. TGA does not seem to be a symptom of an arteriosclerotic pathology nor does it appear to offer a higher risk of heart or cerebrovascular disease and, therefore, antiaggregating therapy would not be indicated in such cases (AU)

Introducción. La amnesia global transitoria (AGT) es una manifestación clínica descrita en muchos estudios, pero cuya fisiopatología no está aclarada. A las hipótesis clásicas de asociación con migraña, epilepsia y la más aceptada de evento isquémico transitorio (AIT), se ha añadido en los últimos años la teoría de insuficiencia valvular yugular sin poder establecerse el origen real del cuadro. Pacientes y métodos. Estudio retrospectivo de 131 pacientes diagnosticados de AGT entre 1993 y 2004 comparados con 262 pacientes con AIT diagnosticados durante el mismo período. Resultados. Edad media de 65,94 años en AGT frente a 71,11 años en AIT. Mayor frecuencia de hipertensión arterial entre los pacientes con AGT y de diabetes mellitus en pacientes con AIT (p < 0,05 en ambos casos). Escasa cardiopatía embolígena en pacientes con AGT. Mayor frecuencia de antecedentes de cardiopatía isquémica y de antecedentes y desarrollo de enfermedad cerebrovascular en los pacientes con AIT respecto a la AGT (p < 0,05). Recurrencia de la AGT del 12%. Mayor porcentaje de hallazgos patológicos en la TC cerebral en pacientes con AIT (p < 0,05). No hay diferencias significativas en cuanto al tratamiento al alta entre los pacientes con AGT y AIT. Conclusión. La AGT no parece ser una manifestación de la patología arterioesclerótica ni presentar mayor riesgo de enfermedad cardio o cerebrovascular y, por lo tanto, no estaría indicado el tratamiento antiagregante (AU)

Amnesia global transitoria y factores de riesgo vascular / Transient global amnesia and vascular risk factors

Introducción. La amnesia global transitoria (AGT) es un síndrome clínico determinado por un episodio de duración inferior a 24 horas consistente en desorientación temporospacial, amnesia retrógrada y anterógrada, con total recuperación posterior. Objetivos. Determinar si la presencia o ausencia de factores de riesgo vascular (FRV) en pacientes con AGT se asocia con datos clínicos y/o exploratorios diferentes. Pacientes y métodos. Estudio retrospectivo de dos grupos de 13 y 12 pacientes con AGT, que presentaban o no FRV, respectivamente. Se determinaron las variables: FRV, edad, antecedentes de migraña, factores desencadenantes, duración y repetición de los episodios, síntomas neurológicos asociados y hallazgos obtenidos mediante neuroimagen, eco-Doppler de troncos supraórticos y Doppler transcraneal. Los datos obtenidos fueron sometidos a estudio estadístico mediante análisis univariante con el test de probabilidad exacta de Fisher. Resultados. Los estudios estadísticos no mostraron diferencias significativas de las variables obtenidas entre los grupos de pacientes. Conclusiones. La AGT se ha relacionado preferentemente con la migraña, epilepsia y con la patología vascular cerebral, aunque su etiología no ha sido totalmente determinada. En el presente estudio se comparan los datos clínicos entre dos grupos de pacientes con y sin FRV que han sufrido AGT. La ausencia de diferencias significativas entre ambos inclina a desestimar la etiología vascular como único origen de este síndrome. Se ha propuesto recientemente como mecanismo fisiopatológico la depresión propagada de Leao. Según esta teoría, la patología vascular podría actuar como desencadenante, pero no probablemente como factor etiológico. Los hallazgos del presente estudio podrían apoyar esta tesis (AU)

Introduction. Transient global amnesia (TGA) is a clinical syndrome determined by an episode of less than 24 hours consisting of temporo-spatial disorientation with retrograde and anterograde amnesia followed by complete recovery. Objectives. To determine whether the presence or absence of vascular risk factors (VRF) in patients with TGA is associated with different clinical data and/or examination findings. Patients and methods. A retrospective study was made of two groups of 13 and 12 patients with TGA, who presented with and without VRF, respectively. The following variables were determined: VRF, age, a previous history of migraine, triggering factors, duration and repetition of the episodes, associated neurological symptoms and findings obtained by neuroimaging, eco-Doppler of the supra-aortic trunks and transcranial Doppler. The data were subjected to statistical analysis by univariate analysis with Fischer’s exact probability test. Results. The statistical studies showed no significant differences between the variables obtained in the two groups of patients. Conclusions. Transient global amnesia has been particularly related to migraine, epilepsy and cerebral vascular pathology, although its aetiology has not been fully determined. In this study we compare clinical data between the two groups of patients with and without VRF who have had TGA. The lack of significant differences between them tends to rule out a vascular aetiology as the sole cause of this syndrome. Recently Leao’s propagated depression has been suggested as the physiopathological mechanism involved. According to this theory, the vascular pathology might act as the trigger but probably not as the aetiological factor. The findings of our study may support this thesis (AU)

Estado crepuscular y delito. A propósito de un caso / Dreamy state and crime. A propose of a case

Presentamos un caso de delitos cometidos por un varón joven en un contexto de estado crepuscular. Estudiamos los aspectos clínicos, haciendo los diversos diagnósticos diferenciales y los aspectos psiquiátrico-forenses relacionados con los delitos imputados. Igualmente tratamos de establecer una hipótesis etiopatogénica de los mismos (AU)