Transcortical mixed aphasia due to cerebral infarction in left inferior frontal lobe and temporo-parietal lobe

We present a case of transcortical mixed aphasia caused by a cerebral embolism. A 77-year-old right-handed man was admitted to our hospital with speech disturbance and a right hemianopia. His spontaneous speech was remarkably reduced, and object naming, word fluency, comprehension, reading and writing were all severely disturbed. However, repetition of phonemes and sentences and reading aloud were fully preserved. Although magnetic resonance imaging (MRI) showed cerebral infarcts in the left frontal and parieto-occipital lobe which included the inferior frontal gyrus and angular gyrus, single photon emission CT revealed a wider area of low perfusion over the entire left hemisphere except for part of the left perisylvian language areas. The amytal (Wada) test, which was performed via the left internal carotid artery, revealed that the left hemisphere was dominant for language. Hence, it appears that transcortical mixed aphasia may be caused by the isolation of perisylvian speech areas, even if there is a lesion in the inferior frontal gyrus, due to disconnection from surrounding areas.     

A study on restriction of the areas working in speech function--application of multivariate analysis of aphasia test data and of lesions on CT images, by composing a "restricted-aphasia-lesion-map"

Computed tomography (CT) gave a large contribution to morphological analysis of the aphasia syndromes. The aphasia problems are, however, still controversial and have many unresolved issues, even from a morphological point of view. In most cases with cerebral vascular lesion causing speech dysfunction, we are able to define an extent of density change on CT images. But its extent seems to be often not consistent with the area supposed to be deranged in functional work-up of speech. CT appearance of some areas may be little changed or normal when those areas are to be in poor condition in their functional maintenance. This may be due to such a vascular supply which permits brain tissues to be sustained but which does not work for their function to be normally performed. From 642 cases with cerebral vascular lesion we reviewed CT images of 382 cases: 171 cases having a lesion in the left hemisphere and 46 of them showing aphasia syndrome; 151, a lesion in the right hemisphere alone and 3, aphasic; and 60 cases having lesions on both sides and 7 showing aphasia syndrome. First, we determined anatomically the extent of CT change in 102 cases, all right-handed, with a lesion in the left hemisphere. The extents were piled and made up to a "non-aphasia-lesion-map". This map was used for eliminating those areas as not working in speech function. The other map of the areas was made out of CT images of aphasia cases (33 cases including one agraphia). The latter map was put upon the "non-aphasia-lesion-map", so that the very area working in speech function could be more restricted. The third map, "restricted-aphasia-lesion-map" demonstrated those areas related to speech function: (1) the region limited around the three rami in the Sylvian fissure (Broca A); (2) the inferior frontal gyrus and the posterior aspect of the middle frontal gyrus (Broca B); (3) the inferior aspect of the cortex and subcortex of the Reil's island; (4) most of the middle temporal gyrus, the posterior third of the superior temporal gyrus, a large portion of the supramarginal gyrus and a part of the limbic system; (5) a large portion of the limbic system; (6) the anterior aspect of the superior frontal gyrus; and (7) the corpus callosum. The Standard Language Test for Aphasia (SLTA) was applied for 33 cases of aphasia.(ABSTRACT TRUNCATED AT 400 WORDS)     

Imaging in primary progressive aphasia

Primary progressive aphasia (PPA) presents with aphasia, with or without other minor cognitive dysfunction. We report five patients with PPA to show the correlation between their clinical signs and imaging findings. The patients can be divided into those with nonfluent (group 1) and those with fluent (group 2) aphasia. The characteristic speech impairment was bradylalia in group 1 and word amnesia in group 2. Impairment of comprehension was common but mild in both groups. On MRI, patients in group 1 showed predominantly left frontal and perisylvian atrophy with reduced uptake in the same region on single photon emission computed tomography (SPECT) using technetium-99m hexamethyl propyleneamine oxime (^99mTc HMPAO). Patients in group 2 showed left temporal atrophy involving the superior, middle and inferior temporal gyri, hippocampus and parahippocampal gyrus on MRI and reduced uptake in the same region on SPECT. These findings correlated well with the functional anatomy of speech impairment. Received: 19 August 1996 Accepted: 9 September 1996     

Correlación neurorradiológica de las afasias. Mapa cortico-subcortical del lenguaje

Aphasia is an acquired language disorder due to a cerebral lesion; it is characterized by errors in production, denomination, or comprehension of language. Although most aphasias are mixed, from a practical point of view they are classified into different types according to their main clinical features: Broca's aphasia, Wernicke's aphasia, conduction aphasia, transcortical aphasia, and alexia with or without agraphia. We present the clinical findings for the main subtypes of aphasia, illustrating them with imaging cases, and we provide an up-to-date review of the language network with images from functional magnetic resonance imaging and tractography.     

Magnetoencephalography in children with Landau-Kleffner syndrome and acquired epileptic aphasia

BACKGROUND AND PURPOSE: Landau-Kleffner syndrome (LKS) is epileptiform aphasia acquired during childhood and occurring in children with previously normal language development. The epileptiform activity in these children is thought to result in a functional ablation of eloquent speech areas. The purpose of this study was to investigate the usefulness of magnetoencephalography (MEG) for localizing the source of epileptiform activity in these patients. METHODS: Nineteen patients with acquired aphasia and a suspected diagnosis of LKS were referred for MEG evaluation. Patients ranged in age from 4 to 14 years. Fourteen MEG studies were performed on a 74-channel system, four on a 148-channel whole-head system, and one on a 37-channel system. RESULTS: Thirteen of the 19 patients had perisylvian MEG spikes. In 10 of the patients, the spikes were bilateral, and in three they were unilateral. Four other patients had non-sylvian spikes, and two patients had no spikes recorded. The results of MR imaging were normal or noncontributory for all 19 patients. CONCLUSIONS: MEG can play a useful role in evaluating children with LKS and acquired epileptiform aphasia, both in diagnosis and in aiding presurgical localization of epileptiform activity when surgery is being considered.     

The superior longitudinal fasciculus and speech arrest

We present a 59-year-old woman with recurrent glioblastoma multiforme involving the left medial frontal and cingulate gyri. Diffusion tensor imaging (DTI) showed inferior-lateral tumor border proximity to the superior-medial (supracallosal) portion of the left frontal superior longitudinal fasciculus (SLF). Dissections of the tumor border contacting the dominant SLF caused speech arrests 8 times, with full recovery. At postoperative day 2, edema caused transient mild aphasia and paraphasic errors. Postoperative DTI showed an inferior-lateral resection cavity in immediate proximity to the supracallosal aspect of the left SLF. The case demonstrates excellent correlation between tumor border proximity to the dominant SLF shown at DTI and speech deficits caused by intraoperative dissections and postoperative edema. The case is the first to demonstrate speech arrest associated with lesion proximity to the supracallosal aspect of the SLF. Other SLF-related deficits are reviewed.     

Subcortical aphasia after striatocapsular infarction: quantitative analysis of brain perfusion SPECT using statistical parametric mapping and a statistical probabilistic anatomic map.

This study examined the relationship between the severity of aphasia and regional cerebral perfusion on brain SPECT using statistical parametric mapping (SPM) and a statistical probabilistic anatomic map (SPAM) in patients with a striatocapsular infarction (SCI) along with the other clinical and imaging findings. METHODS: The subjects were 16 right-handed Korean-speaking patients with a left SCI who underwent 99mTc-ethylcyteinate dimer (99mTc-ECD) SPECT (8.1 +/- 4.8 d [mean +/- SD] after onset). MRI showed that no patient had any abnormality in the cerebral cortex (6.8 +/- 6.0 d after onset). The aphasia quotient (AQ), which is a measure of the severity of aphasia, was obtained by using the Korean version of the Western Aphasia Battery (5.3 +/- 3.9 d after onset). For quantitative evaluation of cerebral perfusion, the asymmetry indices (AIs) for subcortical and cortical areas were calculated using SPM and SPAM. The infarct size was measured using MRI. RESULTS: Aphasia occurred in 15 (2 global, 7 transcortical, and 6 anomic aphasia) of the 16 patients. Left cerebral cortical hypoperfusion was observed in all 15 patients with subcortical aphasia. Aphasia was more severe in 6 patients with extensive cerebral cortical hypoperfusion than in the remaining 10 patients (AQ = 41.8 +/- 25.2 points vs. 84.2 +/- 7.7 points [mean +/- SD], P = 0.001). There was an association between the AQ and age (rho = -0.665), infarct size (rho = -0.594), AIs of the frontal cortex (rho = -0.653), temporal cortex (rho = -0.782), parietal cortex (rho = -0.694), whole cerebral cortex (rho = -0.768), and the cerebellar cortex (rho = 0.765). Voxel-based SPM analysis showed a significant positive correlation between the AQ and the perfusion of the left temporal cortex and the right cerebellum. CONCLUSION: The severity of subcortical aphasia after a left SCI without cortical abnormalities on MRI is associated with the extent and severity of the left cerebral cortical hypoperfusion on brain perfusion SPECT performed during the subacute stage, particularly in the left temporal cortex. Quantitative brain perfusion SPECT using SPM and SPAM can help in evaluating subcortical aphasia in a SCI because it provides functional information that cannot be obtained by morphologic imaging.     

CT identification of cortical speech areas in the human brain

In four human left cerebral hemispheres the cortical speech areas were identified, having been marked by differential color code before transverse sectioning. The results from the anatomic dissection specimens were compared with thin CT sections in normal individuals, the CT plane being aligned to the orbitomeatal plane as an external reference, and thus closely parallel to the bicommissural plane, as an internal reference. The same cortical structures were identified in the CT sections. A strategic approach to CT examination of the cortical speech areas is formulated, based on the external-internal system of reference.     

Language disturbances from mesencephalo-thalamic infarcts

Summary The authors report the cases of two patients with CT-documented paramedian mesencephalo-thalamic infarcts, showing language disturbances. The first patient showed a non fluent, transcortical motor-like language disorder. The CT study disclosed that it was the dorso-median thalamic nucleus that was mostly involved in both cases. These findings agree with a few previous pathological studies suggesting that the paramedian thalamic nuclei, particularly the dorso-median nucleus may play some role in language disturbances. However the anatomical basis for thalamic aphasia remains speculative, taking into account the importance of cortical connections in the origin of subcortical neuropsychological disturbances.     

Proton chemical shift imaging in pick complex

BACKGROUND AND PURPOSE: Pick complex (PC) is the name given to a group of diseases comprising Pick disease and its variations, all of which have a large degree of pathologic and clinical overlap. Because of this overlap, the observation of neuropathologic changes in vivo is difficult, although these changes play important roles in the criteria used for classification. The purpose of this study was to evaluate changes in brain metabolism in PC with proton chemical shift imaging ((1)H-CSI). METHODS: Nine patients with PC (three each with frontotemporal dementia, corticobasal degeneration [CBD], and primary progressive aphasia [PPA]) and five healthy subjects underwent (1)H-CSI. Volumes of interest were selected at the level of the basal ganglia by using a spin-echo sequence (TR/TE, 2000/13). Peak areas and ratios of N-acetylaspartate (NAA), creatine (Cr), and choline (Cho) were calculated in voxels in the basal ganglia and perisylvian regions. RESULTS: Reduced NAA/Cho ratios were observed in the right basal ganglia of the patients with PC. In patients with CBD or PPA, low NAA/Cr values were detected in the right perisylvian region. CONCLUSION: In PC, (1)H-CSI decreased NAA values in a wide area. Significantly reduced NAA levels in the right hemisphere in patients with PC suggests a neurodegenerative change and may reflect cases in which the right hemisphere is dominantly affected, compared with the left hemisphere. (1)H-CSI provided information that could not be obtained with other imaging techniques. Thus, (1)H-CSI may provide useful information for understanding the pathologic process underlying PC.     

Brain SPECT imaging in progressive aphasia.

Progressive aphasia without dementia is a relatively uncommon neurobehavioral syndrome. The initial presentation of progressive aphasia without cognitive impairment may pose a diagnostic dilemma. The authors report a patient with progressive aphasia. The initial neuro-imaging studies (MRI, CT) were not diagnostically helpful. However, brain SPECT imaging with Tc-99m HMPAO clearly demonstrated a left temporal lobe abnormality. This report discusses the potential clinical usefulness of brain SPECT imaging in the evaluation of neurobehavioral disorders.     

Local cortical hypoperfusion imaged with CT perfusion during postictal Todd’s paresis

Introduction Postictal (“Todd’s”) paralysis, or “epileptic hemiplegia,” is a well-known complication of focal or generalized epileptic seizures. However, it is unclear whether the pathophysiology of Todd’s paralysis is related to alterations in cerebral perfusion. We report CT perfusion findings in a patient presenting with postictal aphasia and right hemiparesis. Methods A 62-year-old woman with a history of alcohol abuse, closed head injury and posttraumatic epilepsy, presented with acute onset aphasia and right hemiparesis. A non-contrast head CT scan demonstrated no acute hemorrhage. Left hemispheric ischemia was suspected, and the patient was considered for acute thrombolytic therapy. MRI revealed a subtle increase in signal intensity involving the left medial temporal, hippocampal and parahippocampal regions on both T2-weighted FLAIR and diffusion-weighted sequences. CT angiography and CT perfusion study were performed. The CT perfusion study and CT angiography demonstrated a dramatic reduction in cerebral blood flow and blood volume involving the entire left hemisphere, but with relative symmetry of mean transit time, ruling out a large vessel occlusion. Results Clinical resolution of the aphasia and hemiparesis occurred within a few hours, and correlated with normalization of perfusion to the left hemisphere (detected by MR perfusion). Conclusion This unique case is the first in which clinical evidence of Todd’s paralysis has been correlated with reversible postictal hemispheric changes on CT and MR perfusion studies. This is important because CT perfusion study is being used more and more in the diagnosis of acute stroke, and one needs to be careful to not misinterpret the data.     

99mTc-HMPAO brain SPECT in a case of HSV encephalitis

We present a case of encephalitis caused by Herpes Simplex Virus in a 57 year old woman. The acute picture was suggestive of viral infection without associated neurological symptoms. Due to the posterior appearance of neurological focality, cerebral spinal fluid (CSF) was analyzed. It showed pleocytosis and lymphocytosis, inflammatory process data, and serological test with positivity for Simple Herpes Virus (SHV) subtypes I and II. During admission, other complementary tests were performed: EEG, CT, MRI, cerebral perfusion SPECT; the later supplied significant data regarding anatomical neuroimaging (CT, MRI) in regards to bihemispheral extension of the encephalic condition. Furthermore, after clinical discharge, persistent metabolic abnormality was demonstrated in temporal cortex, responsible for concomitant mixed aphasia.     

Regional brain blood flow in congenital dysphasia: studies with technetium-99m HM-PAO SPECT

Congenital dysphasia is a developmental speech disorder not explained by deafness, phonation disorder, mental retardation, neurologic lesion, or psychiatric disease. The existence of brain lesions has often been postulated but conventional investigations fail to demonstrate any cerebral abnormality. By means of [99mTc]hexamethyl-propyleneamine oxime (HM-PAO) brain single photon emission computed tomography (SPECT) we have studied 14 children suffering from congenital dysphasia. The brain computed tomographic scan was normal in all cases. In two patients with expression impairment the SPECT study demonstrated a hypoperfusion in the inferior frontal convolution of the left hemisphere, involving the Broca's area. In nine of 12 patients with global dysphasia (deficits in both comprehension and expression), SPECT study showed two hypoperfused areas: an abnormality in the left temporoparietal region and a hypoactivity in the upper and middle areas of the right frontal lobe. These results suggest that congenital dysphasia could be due, like acquired aphasia, to specific impairment of the language cerebral areas and that brain SPECT studies with [99mTc]HM-PAO could be useful for a better comprehension of the physiopathology of these disorders.     

Broca失语症语言功能区相关白质结构的DTI研究

目的:通过扩散张量成像(DTI)对Broca失语症患者的语言功能区相关纤维结构进行研究,探讨Broca失语症脑内白质结构改变的特征。方法:使用Siemens Trio 3.0T MR扫描机对30例Broca失语症患者和20例健康成人进行常规序列及DTI扫描,在Siemens Leonado工作站上进行后处理,计算Broca区、Wernicke区及弓状束的各向异性(FA)参数。结果:30例Broca失语症病变均位于左侧大脑半球。失语组左、右侧Broca区FA平均值分别为0.208±0.053及0.284±0.056,对照组左侧Broca区FA平均值为0.296±0.054,失语组左侧Broca区FA平均值与右侧及对照组差异均具有显著性意义(P均<0.05);失语组Wernicke区FA平均值左、右两侧差异无显著性意义(P=0.445>0.05);失语组左侧弓状束FA平均值较右侧及对照组左侧降低(以前部及中部为著),且差异均具有极显著性意义(P均<0.001)。结论:语言功能区的损伤可引起Broca失语症,其纤维通路的损伤亦可导致失语症的发生。     

Pseudo-reorganization of language cortical function at fMR imaging: a consequence of tumor-induced neurovascular uncoupling

A left-handed patient with a grade II left frontal lobe astrocytoma had spontaneous seizures causing speech arrest and uncontrolled right upper extremity movements. Word-generation functional MR (fMR) imaging showed activity nearly exclusively in the right inferior frontal gyrus. The clinical history of the speech arrest and the intraoperative mapping proved left-hemisphere language dominance. Tumor involvement of the left inferior frontal gyrus caused uncoupling of the blood oxygenation level-dependent (BOLD) and neuronal response, leading to the erroneous fMR imaging appearance of right-hemisphere language dominance. Discrepancies between BOLD and intraoperative mapping in areas near lesions illustrate the complementary nature of these techniques.     

Clinical characteristics of speech-language dysfunctions in thalamic aphasia

The aim of this study was to investigate the characteristic symptom cluster and the course of aphasia in 12 patients with single left thalamic lesion verified by CAT scan. The testing of language disorder was performed by standard linguistic tests for aphasia in the acute stage and one month after the insult. Although this clinical syndrome varied greatly it was possible to point out some common characteristics. Spontaneous speech was fluent, easily articulated, grammatically correct, with preserved melodic line. Word finding and understanding were impaired. The impaired comprehension and naming were prominent in all patients with different severity. Repetition skills were intact. During the naming testing patients accomplished better results after semantic help than after phonetic help. Verbal paraphasia errors appeared more frequently (9.78) than neologistic (2.22) and literal paraphasias (1.78). Results of the language fluency tests were worse during semantic categorization tests (5.50) than during animal naming (9.89). On the basis of these facts it was presumed that aphasia in patients with dominant thalamic lesion was the result of lexicosemantic language disorder. It was statistically proved that recovery from aphasia in these cases tended to be significant and rapid.     

Transient ischemic attack due to multiple spontaneous calcified embolus of the cerebral arteries on a calcified mitral and aortic stenosis

We report a case of calcified mitral and aortic stenosis revealed by a reversible ischemic stroke. A 59-year-old male patient, with background of hypertension, kidney failure, diabetes, and dyslipidemia, presented with neither acute onset of right-sided hemiparesis without aphasia nor any loss of consciousness. Head computed tomography (CT) revealed multiple rounded and amorph calcified high-density calcifications within the distal segments of both sylvian and posterior cerebral arteries. Angiographic CT of the carotids didn''t reveal any stenosis or atherosclerotic plaques. Thoracic CT showed massive mitral and aortic valvular calcifications with a left ventricular hypertrophy.     

腹内未降睾丸巨大纯精原细胞瘤六例CT资料分析

目的 探讨螺旋CT对腹内未降睾丸巨大纯精原细胞瘤的诊断价值.方法 回顾性分析经手术病理证实的6例巨大的腹内未降睾丸纯精原细胞瘤的螺旋CT表现.结果 6例肿块长轴与同侧肾下极和腹股沟内环的连线一致.供血动脉均为同侧睾丸动脉,5例显示睾丸静脉引流.同侧睾丸及精索未显示,2例肿块尾端见未退化的睾丸引带.同侧肾脏受压上移.肿块呈囊实混合型,内侧坏死明显,其内可见条状纤维血管分隔,实性部分轻度均匀强化.所有肿块内未见钙化或脂肪.结论 螺旋CT是腹内巨大精原细胞瘤术前定位定性诊断的一种有用的影像手段.     

脑卒中后命名性失语病灶部位分布及失语恢复情况

 目的 观察脑卒中后命名性失语病灶部位分布及失语恢复情况。方法 收集2011-01至2012-07在垂杨柳医院神经内科住院存在失语症的脑卒中患者93例,9例为命名性失语,对其中6例发病后1、2、4、6个月的失语恢复情况进行随访观察,采用西部失语症成套检查(Western Aphasia Battery, WAB)进行语言评价,计算出失语商(aphasia quotient, AQ),根据AQ值的变化,判断失语恢复的程度。结果 命名性失语患者病灶的部位不仅位于左侧颞枕交界区、左侧颞叶,而且还可发生于左侧基底节区、放射冠。命名性失语失语程度较轻,患者在前2个月内恢复显著,第4个月时AQ值为94.42±2.30,已完全恢复。结论 命名性失语发生的部位存在多样性,命名性失语程度较轻,恢复较好。