短暂性脑缺血发作的DWI异常表现和临床特点的关系

目的探讨磁共振弥散成像(DWI)责任病灶在短暂性脑缺血发作(TIA)诊断与治疗中的价值及相关因素分析。方法 124例TIA患者在发病3天内行头颅MRI及DWI检查,根据DWI有无异常,分为两组(DWI正常组及DWI异常组),并比较这两组的临床资料情况。结果 48例患者有DWI异常(38.7%),76例无异常(61.3%),发作持续时间较长(≥60min)、发作频繁、有运动障碍、失语、脑卒中或TIA史及糖尿病的TIA患者更易于出现DWI异常。结论在临床诊断的TIA患者中,症状持续时间较长、发作频繁、运动障碍、失语、脑卒中或TIA史及糖尿病是与DWI异常显著相关的因素。     

Thalamic aphasia associated with mitochondrial encephalopathy,lactic acidosis,and stroke-like episodes: A case report

BackgroundMitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with aphasia is a rare disorder, with the associated aphasia reported as either Wernicke’s or Broca’s. Herein, we report a patient with MELAS complicated by thalamic aphasia.CaseA 15-year-old right-handed girl presented with headache, nausea, right homonymous hemianopsia, and aphasia. She could repeat words said by others, but had word-finding difficulty, paraphasia, and dysgraphia. Brain MRI revealed abnormal signals from the left occipital lobe to the temporal lobe and left thalamus, but Wernicke’s area and Broca’s area were not involved. Additionally, she had short stature, lactic acidosis, bilateral sensorineural hearing loss, and a maternal family history of diabetes and mild deafness. Based on clinical findings and the presence of a mitochondrial A3243G mutation, she was diagnosed with MELAS. With treatment, the brain MRI lesions disappeared and her symptoms improved. Her aphasia was classified as amnesic aphasia because she could repeat words, despite having word-finding difficulty, paraphasia, and dysgraphia. Based on MRI findings of a left thalamic lesion, we diagnosed her with thalamic aphasia.ConclusionThalamic aphasia may be caused by MELAS. Assessment of whether repetition is preserved is important for classifying aphasia.     

Aphasic or amnesic status epilepticus detected on PET but not EEG

Purpose:   To describe five patients with ictal aphasia and one patient with ictal amnesia, who had focal positron emission tomography (PET) hypermetabolism but no clear ictal activity on electroencephalography (EEG).
Methods:   ¹⁸F-Fluorodeoxyglucose (FDG)–PET scans with concomitant EEG were obtained in five patients with suspected ictal aphasia or ictal amnesia without ictal activity on EEG. We reviewed medical history, EEG, imaging data, and treatment outcome.
Results:   Brain magnetic resonance imaging (MRI) showed no structural abnormalities in any of the patients. EEG showed left temporal irregular delta activity in three patients, with aphasia and nonspecific abnormalities in two other patients, all without clear ictal pattern. All patients demonstrated focal hypermetabolism on PET scan. The hypermetabolism was in the left frontotemporal region in patients with ictal aphasia and in the bilateral hippocampal region in the patient with amnesia. Three patients who received intravenous benzodiazepines during their episodes had transient clinical improvement. With antiepileptic drug (AED) treatment, symptoms gradually resolved in all patients. Concomitant resolution of PET hypermetabolism was documented in three patients who had follow up scans. One patient with ictal aphasia later developed recurrent episodes, each with recurrent PET hypermetabolism. This patient and one other patient required immune-modulating therapy in addition to AEDs.
Discussion:   FDG-PET imaging should be considered as a diagnostic tool in patients with suspected ictal aphasia or amnesia, who fail to show clear evidence of ictal activity on EEG.     

Parkinson’s disease showing progressive conduction aphasia

Patients with Parkinson’s disease (PD) may develop progressive dementia late in their clinical course. Dementia in PD is mostly related to neuropathological findings of extensive Lewy bodies (LBs), with or without the coexistence of Alzheimer’s disease (AD) pathology. Aphasia has been reported in patients with LB diseases with AD pathology; however, there have been no reports of typical PD patients developing progressive aphasia during their clinical course. We describe a female PD patient who later developed progressive conduction aphasia characterized by phonemic paraphasia and disturbance in repetition of short sentences without disturbance in writing or auditory comprehension. No episodes of fluctuations of attention, memory complaints, or planning errors were observed. She experienced episodes of visual hallucination. Her low scores on the Mini-Mental State Examination suggested impairment of orientation and attention, and her scores on Raven’s Coloured Progressive Matrices test indicated impaired visuospatial functions. However, her cognitive deficits were not sufficiently severe to impair her daily life. Brain magnetic resonance images revealed atrophy of the left superior temporal gyrus and widening of the left sylvian fissure. [¹⁸F]-fluorodeoxyglucose positron emission tomography revealed glucose hypometabolism in the left cerebral hemisphere. These findings may be related to conduction aphasia. During the progression of PD lesions, the brainstem LB is assumed to take an upward course, extend to the limbic system, and then extend to the neocortex. Conduction aphasia observed in our patient may be associated with an unusual progression of the LB pathology from the brainstem to the left temporoparietal lobe.     

Recurrent aphasic status epilepticus after prolonged generalized tonic-clonic seizures versus a special feature of Todd's paralysis

Postictal aphasia may be a feature of Todd's paralysis or the presentation of aphasic nonconvulsive status epilepticus (NCSE). We describe a 74-year-old woman with three episodes of aphasic status epilepticus after prolonged generalized tonic-clonic seizures. In the first episode, the NCSE was not definitively diagnosed, but an increase in the epileptic medication led to resolution of the epileptic activity within 2 weeks. During the second episode, NCSE was terminated within 7 days under intensified antiepileptic treatment. In the third episode, phenytoin treatment led to intoxication and resulted in further treatment on an intensive care unit. The patient required several months to recover from this episode. NCSE in the elderly is difficult to recognize, especially when it presents as a prolonged postictal deficit like aphasia. Once diagnosed it has to be treated carefully, because in the elderly, aggressive treatment strategies may be associated with a high risk of adverse events.     

Neuroanatomic correlation of the post-stroke aphasias studied with imaging

BACKGROUND AND PURPOSE: Stroke is the leading cause of disability in many countries. Aphasia is a common sign of stroke that is observed in about one-third of stroke patients and contributes to disease morbidity. However, the relationship between anatomy and different forms of aphasia remains poorly understood. We intend to study the characteristics of aphasia in the acute stage of stroke and to identify neuroanatomical correlates using MRI. METHODS: Lesion sites were selected from 1198 patients with cerebral infarction, who were hospitalized in the stroke unit of our hospital between March 2002 and March 2006. We enrolled 325 patients who fulfilled our criteria. All patients received an MRI examination within 1 week after admission and were evaluated with the Western battery aphasia (WAB) test, in order to determine what type of aphasia they had. The severity of their language deficit was further classified using the Boston diagnostic aphasia examination (BDAE) severity grading standard. RESULTS: Among 1198 cases, five cases with Broca's areas and four cases with Wernicke's areas lesions on MRI works were free of language deficits. Within the 325 patients who demonstrated clinical signs of aphasia, the results of WAB showed that there were 83 Broca' aphasia cases, 48 Wernicke's aphasia cases, 12 conduction aphasia cases, 36 transcortical motor aphasia cases, 17 transcortical sensory aphasia cases, 19 transcortical mixed aphasia cases, 58 global aphasia cases and 52 anomic aphasia cases. Two hundred and eighty-eight cases were located within classical language centers while 37 cases were located at other sites. In 325 aphasia patients with grade criteria of BDAE of grades 0, 1, 2, 3 or 4, there were 84, 79, 77, 63 and 22 cases respectively. Many of cases with grades 0 and 1 were distributed within classical language centers. CONCLUSION: This study showed that it is possible to draw a neuroanatomical map of aphasia that encompasses the 95% of aphasia cases. It also demonstrates that the main determinant of aphasic disorders is the neuroanatomical location of the lesion. Furthermore, this study shows that most lesion locations associated with specific aphasic disorders fit classical data associated with previous aphasia research. More importantly, the language disorders of patients whose lesions were located at classical language centers were more serious. Consequently, this paper demonstrates the power of MRI in prognosticating the potential for a patient to recover from aphasia due to stroke.     

Crossed aphasia: a PET follow up study of two cases.

Two cases of aphasia after right hemispheric stroke in right handed patients are described. The first patient had a severe mixed transcortical aphasia, apraxia and neglect after a lesion involving the right lenticular nucleus and periventricular white matter; aphasia was still present after three months. The second patient had a mild, transient fluent aphasia after a small right hemispheric periventricular lesion. Studies with [18F]FDG and positron emission tomography (PET) showed functional depression extending to the structurally unaffected left hemisphere in both patients in the acute stage. After three months, in the patient with persistent aphasia, metabolism was still reduced in the right hemisphere, with some recovery of hypometabolism on the left, while metabolic values had returned to normal in the patient with full language recovery. A close parallelism between glucose metabolism and clinical course in crossed aphasia is shown, as well as the presence of a functional involvement of the structurally unaffected left hemisphere in the acute stage.     

Non-convulsive status epilepticus presenting with Wernicke's aphasia

Ictal aphasia in adults is a rare phenomenon. Most reported cases manifest with non-fluent (Broca) aphasia. Ictal fluent (Wernicke) aphasia is less common. We report a 47-year-old, right-handed woman that presented with recurrent episodes of non-convulsive seizures in the form of Wernicke's aphasia for 2 weeks. An MRI of the brain showed an old cerebral infarction in the left parieto-occipital area. Scalp EEG revealed continuous periodic sharp waves at the left temporal regions with diffusion to the whole left hemisphere and at occasions to the right. This is followed by variable periods of post ictal slowing. Recurrence of the described ictal pattern was noted. Management of status epilepticus was started in the form of intravenous diazepam and a loading dose of phenytoin and phenobarbitone. After treatment, she improved clinically and the EEG improved with disappearance of the left temporal ictal rhythm and normalization of the EEG background. Thus, establishing the diagnosis of non-convulsive partial status epilepticus manifesting as ictal aphasia.     

Strokes restricted to the insular cortex

OBJECTIVE: To characterize clinically acute insular strokes from four patients with a first ever acute stroke restricted to the insula on MRI. METHODS: The authors studied the clinical presentation of four patients with a first ever acute stroke restricted to the insula on MRI. RESULTS: The authors found five main groups of clinical presentations: 1) somatosensory deficits in three patients with posterior insular stroke (two with a transient pseudothalamic sensory syndrome, one with partial distribution); 2) gustatory disorder in a patient with left posterior insular infarct; 3) vestibular-like syndrome, with dizziness, gait instability, and tendency to fall, but no nystagmus, in three patients with posterior insular strokes; 4) cardiovascular disturbances, consisting of hypertensive episodes in a patient with a right posterior insular infarct; and 5) neuropsychological disorders, including aphasia (left posterior insula), dysarthria, and transient somatoparaphrenia (right posterior insula). CONCLUSION: Strokes restricted to the posterior insula may present with pseudothalamic sensory and vestibular-like syndromes as prominent clinical manifestations, but also dysarthria and aphasia (in left lesions), somatoparaphrenia (right lesions) and gustatory dysfunction and blood pressure with hypertensive episodes in right lesions; we did not find acute dysphagia reported in anterior, insular strokes.     

Episodic receptive aphasia in a child with Landau-Kleffner Syndrome: PET correlates

We report a four-year-old boy with Landau-Kleffner Syndrome (LKS) characterized by episodic receptive aphasia lasting for few weeks followed by gradual recovery of baseline language functions. Neuropsychological evaluation during an episode showed severe impairment in verbal skills and comprehension, but relative preservation of non-verbal skills. Although he could carry on a conversation during remission, neuropsychological evaluation demonstrated findings reflective of receptive language deficits. Prolonged EEG disclosed frequent sharp-wave activity in the left and right temporal regions but no electrographic seizures. Glucose metabolism PET scan during the fourth episode of aphasia revealed intense hypermetabolism in the left temporal neocortex. Awake EEG during the PET tracer uptake period showed 6.0 spikes/min in the left temporal region and 4.0 spikes/min in the right. A repeat PET scan during remission showed hypometabolism in the left temporal cortex. Awake EEG during the FDG uptake period showed 16.0 spikes/min in the right temporal region and 0.3 spikes/min in the left. During his fifth aphasic episode, EEG (without PET) showed 0.16 spikes/min in the right temporal region and none in the left. Intermittent short episodes of predominantly receptive aphasia with near-total recovery between episodes can be one of the clinical presentations of LKS. This case illustrates the dynamic changes of glucose metabolism in the temporal lobe during episodes of aphasia and remission in a case with LKS. The clinical course of our patient with transient EEG and PET findings suggest that glucose metabolism in LKS cannot be attributed solely to interictal epileptiform activities on scalp EEG.     

De-novo simple partial status epilepticus presenting as Wernicke's aphasia

Language disturbances manifesting as brief periods of speech arrest occur with seizures originating in the frontal or temporal lobes. These language disturbances are usually present with other features of seizures or may occur in an episodic fashion suggesting their likely epileptic origin. Sustained but reversible aphasia as the sole manifestation of partial status epilepticus is rare, particularly without a history of prior seizures. A few cases have been described in the literature where Broca's or mixed aphasia seems to be more common than Wernicke's aphasia. Here we describe a patient who presented with Wernicke's aphasia secondary to simple partial status epilepticus but without any other features of seizures. The diagnosis was confirmed on EEG and the aphasia reversed after antiepileptic treatment.     

Subcortical infarction resulting in acquired stuttering

Stuttering is an uncommon presentation of acute stroke. Reported cases have often been associated with left sided cortical lesions, aphasia, and difficulties with other non-linguistic tests of rhythmic motor control. Three patients with subcortical lesions resulting in stuttering are discussed. In one patient the ability to perform time estimations with a computerised repetitive time estimation task was characterised.One patient had a pontine infarct with clinical evidence of cerebellar dysfunction. A second patient had a left basal ganglionic infarct and a disruption of timing estimation. A third patient had a left subcortical infarct and a mild aphasia.These findings expand the reported distribution of infarction that can result in acquired stuttering. Subcortical mechanisms of speech control and timing may contribute to the pathophysiology of acquired stuttering.     

Crossed aphasia with jargon aphasia in two right-handed patients (author's transl)]

Two cases of crossed aphasia in right-handed patients are reported. The oral language of these two patients was characterized by a reduction in its lexical and grammatical content. Their written language, however, was a veritable jargon with anosognosia. The jargon aphasia of the first patient consisted mainly of neologisms. The written language of the second patient was slightly less disorganized and corresponded to an asemantic jargon. The existence of this jargon aphasia gives these two observations an exceptional character in relation to other cases of crossed aphasia in right-handed patients. It supplies new information which can be the basis for discussion on the relations between cerebral laterlization of language functions and manual preference.     

Wernicke's aphasia reflects a combination of acoustic-phonological and semantic control deficits: a case-series comparison of Wernicke's aphasia, semantic dementia and semantic aphasia

Wernicke's aphasia (WA) is the classical neurological model of comprehension impairment and, as a result, the posterior temporal lobe is assumed to be critical to semantic cognition. This conclusion is potentially confused by (a) the existence of patient groups with semantic impairment following damage to other brain regions (semantic dementia and semantic aphasia) and (b) an ongoing debate about the underlying causes of comprehension impairment in WA. By directly comparing these three patient groups for the first time, we demonstrate that the comprehension impairment in Wernicke's aphasia is best accounted for by dual deficits in acoustic-phonological analysis (associated with pSTG) and semantic cognition (associated with pMTG and angular gyrus). The WA group were impaired on both nonverbal and verbal comprehension assessments consistent with a generalised semantic impairment. This semantic deficit was most similar in nature to that of the semantic aphasia group suggestive of a disruption to semantic control processes. In addition, only the WA group showed a strong effect of input modality on comprehension, with accuracy decreasing considerably as acoustic-phonological requirements increased. These results deviate from traditional accounts which emphasise a single impairment and, instead, implicate two deficits underlying the comprehension disorder in WA.     

The syndrome of Gogi (word meaning) aphasia. Selective impairment of kanji processing.

In 1943, Imura described an aphasic syndrome shown by Japanese patients and designated it as Gogi ("word-meaning") aphasia. Salient features are selective impairment of processing kanji or Chinese characters and difficulty in finding access to the lexicon in both production and reception, with preservation of processing kana or phonetic signs, and fluent oral repetition. A patient with this syndrome is presented, with emphasis on the nature of his kanji impairment. Cases of Gogi aphasia in the literature are reviewed and contrasted to cases of Broca's aphasia with selective impairment of kana processing. The implications for a neurolinguistic model of language processing in aphasia are discussed.     

Crossed aphasia: Two new cases

Crossed aphasia is caused by a right-hemisphere lesion in a right-handed person. Although this unusual language lateralisation pattern is a defining characteristic, there is disagreement among authors on additional diagnostic criteria. In addition, there is a significant amount of variability between patients as to the associated symptomatology, such as the presence of apraxic or visuospatial signs. Because of the rarity of crossed aphasia, the understanding of this clinical entity depends entirely on the analysis of published case studies. This paper presents two new cases of crossed aphasia, and discusses the major issues related to crossed aphasia diagnosis and symptomatology. Procedures for the assessment of crossed aphasia patients are also suggested.     

Recurrent limbic and extralimbic encephalitis associated with thymoma

A 33-year-old woman, with a 7-year clinical history of invasive thymoma treated at ages 26 and 30 years by thymectomy and radiation, presented with a generalized convulsion and loss of consciousness. Following the seizure there was no neurological deficit and normal tendon reflexes. Magnetic resonance imaging (MRI) of the brain without gadolinium enhancement revealed multiple small lesions of high signal intensity on T2 and diffusion weighted images located in the cortical area beyond the temporal lobes. Brain biopsy demonstrated encephalitis with activated microglias and activated T-cell infiltration. Within 4 months of treatment with nothing other than anticonvulsant therapy, the lesions visible on the original MRI had completely disappeared and the patient was discharged with no neurological symptoms. The patient subsequently had two more episodes with a variety of symptoms such as incontinence, confusion, aphasia, apallial syndrome, and motor paresis. MRI following these episodes again revealed multiple lesions of similar appearance to those of the first episode, although in different locations, and much larger and more numerous. The patient had steroid pulse therapy after both episodes and the lesions noted on brain MRI disappeared within a few months with minimal neurological complications.     

A case of unilateral opercular syndrome associated with a subcortical lesion

Summary A patient who developed a unilateral opercular syndrome following a cerebrovascular accident is described. Computed tomography showed that the lesion did not affect the opercular cortex, but involved deep white matter and the head of the caudate nucleus of the left hemisphere. Persistent hypophonia and transient aphasia were associated. Comparison with previous cases is discussed.     

Epileptiform Activity in Aphasia of Childhood:An Epiphenomenon?

Isolated aphasia with associated EEG epileptiform activity is a recognized syndrome in children. The relationship of the EEG abnormality and the type and severity of the speech impairment has not been well described. This relationship was studied in two children with severe expressive and receptive aphasia with generalized spike-wave discharges on EEG using prolonged EEG FM radiotelemetry and video recording (TEEG-VR). Speech was compared with 10 children with absence seizures with similar EEG abnormalities also evaluated using TEEG-VR. In addition, 43 cases of aphasia with epileptiform activity on the EEG reported in the English literature were reviewed. Speech abnormalities in absence seizures consisted of speech arrest, decreased speed of speech, and brief periods of partial or complete receptive and expressive aphasia, always directly associated with a spike-wave ictus. Speech abnormalities in acquired or congenital aphasia were not related to epileptiform activity and were characterized by severe articulation difficulties, syntactic transformation, paraphasia, and receptive and expressive aphasia. Anticonvulsants did not alter speech. Based on these two cases and the 43 others reviewed in the literature, it is proposed that epileptiform activity in this syndrome is an epiphenomenon reflecting underlying abnormalities of speech areas rather than the cause of the aphasia.     

Thalamic aphasia secondary to glioblastoma multiforme

BackgroundThalamic aphasia is an unusual clinical presentation of brain neoplasm with few cases reported. Herein, we present a case of an adult woman with thalamic aphasia due to glioblastoma of the thalamus.Case presentationA 57-year-old female patient presented with difficulty walking, slow speech and cognition and altered mental status. At baseline, she was conversant and interactive. Physical examination showed right hemiparesis in addition to word finding difficulties, an impaired naming of objects and semantic paraphasia but preserved repetition and comprehension. The remaining neurological exam was otherwise unremarkable. Brain CT and brain MRI scans showed a left thalamic lesion that is centrally necrotic and peripherally enhancing suggestive of a high-grade neoplasm. Eventually, histopathological examination of brain biopsy confirmed the diagnosis of glioblastoma multiforme. Thalamic aphasia was proposed as an explanation for the neurological symptoms observed in this patient.ConclusionsThis patient demonstrates an unusual presentation of glioblastoma multiforme as thalamic aphasia. It may also point to the potential contribution of the understanding of how thalamic aphasia evolves to characterize the role of the thalamus in language functions.