Primary progressive aphasia presenting as conduction aphasia.

We report a case of a woman with primary progressive aphasia (PPA) who presented with conduction aphasia. A 60-year-old, right-handed, Japanese female suffering from progressive aphasia had difficulty in repeating words and phrases. She displayed phonemic paraphasias but had preserved comprehension and had no cognitive or behavior disorder for more than 6 years after the onset of the condition. She was able to continue to work successfully and to perform all her normal daily activities. T1-weighted magnetic resonance imaging revealed minute dilatation of the left inferior horn and sulci in the left hemisphere, and positron emission tomography revealed mild hypometabolism in the left supramarginal gyrus and its surrounding areas. Therefore, she was diagnosed as suffering from PPA presenting as conduction aphasia. We believe that the progressive conduction aphasia of the patient belongs to one of the fluent forms of PPA, and the ability to continue normal work along with the clinical portrayal of preserved memory and cognition skills may be features of a form of PPA presenting as conduction aphasia.     

原发性进行性失语的临床、影像及语言特征

目的 探讨原发性进行性失语（PPA）的临床、影像及语言特征.方法 PPA患者7例,其中语义性痴呆（SD）6例,进行性非流利性失语（PNFA）1例,收集患者的人口学资料、病史,进行头MRI检查,采用汉语失语成套测验进行语言评估.结果 患者平均发病年龄56岁,均缓慢起病,以语言表达、命名障碍为首发症状.MRI示左侧颞极萎缩为主,病程长的患者左侧额叶和顶叶、右侧颞叶也明显萎缩.语言评估发现所有患者的自发语言、复述、命名、听理解、阅读和书写均不同程度损害.SD患者言语流利,复述、朗读能力下降相对较轻,命名、复杂语句的理解能力损害突出.PNFA言语顿挫吃力,患者列名能力明显下降,但命名相对保存完好.结论 PPA多为老年前期发病,语言障碍为最早、最突出的症状.MRI特征性的改变为额叶和颞极萎缩,左侧为著.其中SD表现为命名性失语和经皮质感觉性失语,PNFA表现为经皮质运动性失语的特征.     

原发性进行性失语一例临床分析

目的 原发性进行性失语（PPA）是一种少见的中枢神经系统变性疾病，国内罕见报道。现报道1例，以提高临床医生对该病的认识。方法 采用韦氏一表、认知能力筛选检查、积木测验、数字广度测验和社会功能问卷等全套神经心理学量表方法，检查和描述了PPA的临床和神经心理学特征；并进行了MRI和PET影像学检查。结果 病人除有单纯性命名性失语外，不伴有其他类型的失语与智能损害及神经系统体征；MRI和PET检查均发现左颞叶明显萎缩。结论 PPA以缓慢进行性失语而不伴有认知功能障碍和神经系统体征为特点，优势半球局灶性额、颞叶病变有诊断意义。     

Brain atrophy in primary progressive aphasia involves the cholinergic basal forebrain and Ayala's nucleus

Primary progressive aphasia (PPA) is characterized by left hemispheric frontotemporal cortical atrophy. Evidence from anatomical studies suggests that the nucleus subputaminalis (NSP), a subnucleus of the cholinergic basal forebrain, may be involved in the pathological process of PPA. Therefore, we studied the pattern of cortical and basal forebrain atrophy in 10 patients with a clinical diagnosis of PPA and 18 healthy age-matched controls using high-resolution magnetic resonance imaging (MRI). We determined the cholinergic basal forebrain nuclei according to Mesulam's nomenclature and the NSP in MRI reference space based on histological sections and the MRI scan of a post-mortem brain in cranio. Using voxel-based analysis, we found left hemispheric cortical atrophy in PPA patients compared with controls, including prefrontal, lateral temporal and medial temporal lobe areas. We detected cholinergic basal forebrain atrophy in left predominant localizations of Ch4p, Ch4am, Ch4al, Ch3 and NSP. For the first time, we have described the pattern of basal forebrain atrophy in PPA and confirmed the involvement of NSP that had been predicted based on theoretical considerations. Our findings may enhance understanding of the role of cholinergic degeneration for the regional specificity of the cortical destruction leading to the syndrome of PPA.     

A case of developmental deep dyslexia: What's left is right

Primary progressive aphasia (PPA) is a progressive neurodegenerative disorder characterized by the deterioration of language functions. The Han language bears some unique features from the Latin languages; however, the features of PPA in the Han language-speaking population are not well understood. In this study, we performed a 3-year follow-up on a Han language-speaking PPA patient with corresponding changes in magnetic resonance imaging (MRI). During the early stage, linguistic analysis revealed several symptoms including difficulty with auditory comprehension, right–left disorientation, reading disorders, and agraphia, specifically the execution of serial oral instructions. This Chinese PPA patient presented with a reading disorder, but his word comprehension ability remained intact. There are two different possible modalities of incorrect writing in this case. The patient also presented with noun–verb double dissociation. The early-stage MRI showed atrophy of the left frontal lobe, which was most severe in the inferior frontal gyrus. Three years later, the patient was found to have progressive atrophy in the parietal, frontal, and temporal lobes, among which the frontal lobe remained the most severely affected region. The brain imaging of the Chinese-speaking PPA patient showed changes similar to those of a Latin language-speaking PPA patient. The prominent change was asymmetrical atrophy in the frontal and temporal lobes. This is the first report of noun–verb double dissociation existing in a Chinese-language speaking PPA patient. The dissociation may be related to an impaired function of the inferior frontal gyrus, which is likely associated with verb-naming in Chinese-speaking people. Several unique features were observed in this case, including impairment in writing ability.     

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.     

An autopsy case of Alzheimer's disease presenting with primary progressive aphasia: A clinicopathological and immunohistochemical study

This report describes an autopsied Alzheimer's disease (AD) patient with primary progressive aphasia (PPA) as an early symptom. The patient developed a progressive speech disturbance at the age of 70 years, and difficulty in comprehension became apparent 2 years later. Magnetic resonance imaging scan disclosed asymmetrical brain atrophy, predominantly on the left temporal lobe. At the age of 74 years, the patient's dementia rapidly progressed with parkinsonism and he died after a disease duration of 6 years. At autopsy, the brain showed a marked temporo‐frontal lobe atrophy, predominantly on the left side. There was severe neuronal loss with gliosis and tissue rarefaction in the atrophied cerebral cortex and amygdala. Many neurofibrillary tangles with neuropil threads were found in the cerebral cortex. Numerous amyloid deposits were distributed throughout the cerebral cortex, accompanied by amyloid angiopathies. This patient was clinically diagnosed with temporal lobe‐dominant Pick's disease, although the possibility of corticobasal degeneration was made. The neuropathological diagnosis was AD with asymmetrical brain atrophy and widespread amyloid angiopathies.     

Aphasia and dementia

Primary progressive aphasia (PPA) is an uncommon neurodegenerative syndrome characterized by a relatively isolated dissolution of language function at the beginning, followed by deterioration of general cognitive function and of activities of daily living after 2 or more years. On account of neuropathological and clinical findings, PPA is supposed to form part of the spectrum of frontotemporal lobar degeneration. We present a case study of a 66-year-old woman with a probable fluent progressive aphasia. She initially experienced word amnesia and developed after 2 - 3 years gradual regression of word comprehension, over-fluent speech with semantic paraphasias, and at last generalized dementia. In addition to minor bilateral cortical volume reduction on CCT, MRI showed left temporal lobe atrophy involving hippocampus, SPECT revealed reduced uptake left frontal and temporal.     

Validating new diagnostic imaging criteria for primary progressive aphasia via anatomical likelihood estimation meta‐analyses

Recently, diagnostic clinical and imaging criteria for primary progressive aphasia (PPA) have been revised by an international consortium (Gorno‐Tempini et al. Neurology 2011;76:1006‐14). The aim of this study was to validate the specificity of the new imaging criteria and investigate whether different imaging modalities [magnetic resonance imaging (MRI) and fluorodeoxyglucose positron emission tomography (FDG‐PET)] require different diagnostic subtype‐specific imaging criteria. Anatomical likelihood estimation meta‐analyses were conducted for PPA subtypes across a large cohort of 396 patients: firstly, across MRI studies for each of the three PPA subtypes followed by conjunction and subtraction analyses to investigate the specificity, and, secondly, by comparing results across MRI vs. FDG‐PET studies in semantic dementia and progressive nonfluent aphasia. Semantic dementia showed atrophy in temporal, fusiform, parahippocampal gyri, hippocampus, and amygdala, progressive nonfluent aphasia in left putamen, insula, middle/superior temporal, precentral, and frontal gyri, logopenic progressive aphasia in middle/superior temporal, supramarginal, and dorsal posterior cingulate gyri. Results of the disease‐specific meta‐analyses across MRI studies were disjunct. Similarly, atrophic and hypometabolic brain networks were regionally dissociated in both semantic dementia and progressive nonfluent aphasia. In conclusion, meta‐analyses support the specificity of new diagnostic imaging criteria for PPA and suggest that they should be specified for each imaging modality separately.     

Two cases of frontotemporal dementia with predominant temporal lobe atrophy

Frontotemporal dementia (FTD) is a subtype of frontotemporal lobar degeneration, which also includes semantic dementia (SD) and progressive non‐fluent aphasia. Frontotemporal dementia is characterized by changes in personality and behavioral abnormalities, generally associated with predominant frontal lobe atrophy. Conversely, SD is typically characterized by Gogi (word meaning) aphasia based on semantic memory impairment and is associated with predominant temporal lobe atrophy. However, in the present cases, we diagnosed FTD on the basis of clinical symptoms, such as disinhibition, indifference, and stereotypy, without semantic memory impairment, even though neuroimaging showed predominant temporal lobe atrophy. We suggest that clinical symptoms are the most important cues for an accurate clinical diagnosis and there is no exclusive relationship between the syndrome and atrophy of the temporal lobes.     

Longitudinal imaging and deterioration in word comprehension in primary progressive aphasia: Potential clinical significance

Background: Three variants of primary progressive aphasia (PPA), distinguished by language performance and supportive patterns of atrophy on imaging, have different clinical courses and the prognoses for specific functions. For example, semantic variant PPA alone is distinguished by impaired word comprehension. However, sometimes individuals with high education show normal performance on word-comprehension tests early on, making classification difficult. Furthermore, as the condition progresses, individuals with other variants develop word-comprehension deficits and other behavioural symptoms, making distinctions between variants less clear. Longitudinal brain imaging allows identification of specific areas of atrophy in individual patients, which identifies the location of disease in each patient.

Aims: We hypothesised that the areas of atrophy in individual PPA participants would be closely correlated with the decline in word comprehension over time. We propose that areas where tissue volume is correlated with word comprehension are areas that: (1) are essential for word comprehension, (2) compensate for word comprehension in some individuals with semantic variant PPA early in the course, and (3) show atrophy in individuals with logopenic and nonfluent variant PPA only late in the course.

Methods and Procedures: Fifteen participants with PPA (five logopenic variant PPA; eight semantic variant PPA; two nonfluent/agrammatic variant PPA; mean age 67.8), underwent high resolution magnetic resonance imaging and cognitive tests at least 9 months apart. The correlations between change in regional volumes and change in auditory word-comprehension scores were investigated using Spearman test.

Outcomes & Results: While scores on auditory word comprehension at Time 1 were correlated with volume loss in right and left temporal pole and left inferior temporal cortex (areas of atrophy associated with semantic variant PPA), deterioration in auditory word comprehension from Time 1 to Time 2 was associated with individual atrophy in left middle temporal cortex, left angular gyrus, and right inferior and middle temporal cortex.

Conclusions: Progressive atrophy in focal areas surrounding left temporal pole and left inferior temporal cortex, and right homologous area is closely related to progressive decline in auditory word comprehension. These correlations likely reflect areas that compensate for subtle deficits early in the course of semantic variant PPA, as well as areas that are critical for auditory word comprehension that eventually atrophy in individuals with other variants of PPA. Individual patterns of atrophy also help us understand and predict the clinical course of individuals, such as associated behavioural or motor deficits.     

A case of Gogi aphasia with predominantly left temporal and parietal lobe atrophy]

We report a 68-year-old right-handed Japanese woman who had a history of progressive difficulty in understanding speech and naming. Neuropsychological examination presented Gogi (word meaning) aphasia and impairment of semantic memory for some common objects. She also presented acalculia and mild constructional impairment. There was no evidence of impairment in elementary perception and motor skills. Her memory performance of visual task was within normal range. She had neither personality change nor behavioral disorder. Magnetic resonance (MR) imaging showed atrophy in the left temporal lobe and the left parietal lobe. Single photon emission computed tomography (SPECT) scans demonstrated a decrease of regional cerebral blood flow in the atrophic sites and the left frontal lobe. We pointed out that the atrophy of the parietal lobe was atypical in the early stage of cortical degenerative disease presenting Gogi aphasia, in addition to in the light of classification of Fronto-Temporal Lobar Degeneration (FTLD).     

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.     

From primary progressive aphasia to corticobasal syndrome: two clinical and rCBF functional reports

We describe two cases, both presenting with a 2-year history of isolated language disorders, one compatible with logopenic variant and the other with non-fluent variant of primary progressive aphasia (PPA). Afterwards, each developed a corticobasal syndrome (CBS) with alien limb phenomenon and a multi-domain cognitive impairment. Regional cerebral perfusion (rCBF) study using 99mTc-ECD single photon emission computed tomography (SPECT) revealed hypoperfusion patterns consistent with these aphasia types and with the presence of limb apraxia. We report two cases of PPA variants associated with CBS and we suggest that SPECT rCBF correlates can be useful in making a differential diagnosis within the PPA spectrum.     

Progressive anomia without semantic or phonological impairment

We describe a 59-year-old woman, M.T., with a progressive language impairment and neuroimaging findings of decreased perfusion (SPECT) and focal atrophy (MRI) in the left temporal region. The most prominent feature of her cognitive profile was a profound and progressive impairment in naming. In spite of this, she performed normally on tests of semantic processing and phonological output. Her spontaneous speech was fluent with preserved syntax and articulation but with notable word-finding problems. All other cognitive abilities were relatively stable and intact. These features are not typical of either fluent or non-fluent forms of neurodegenerative language disturbance. The cognitive mechanisms that may underlie this case are discussed.     

Abstracts Presented at the British Neuropsychological Society Autumn Meeting,October/November 2006

Classifying primary progressive aphasia (PPA) into variants that may predict the underlying pathology is important. However, some PPA patients cannot be classified. A 78-year-old woman had unclassifiable PPA characterized by anomia, dysarthria, and apraxia of speech without agrammatism. Magnetic resonance imaging revealed left mesial temporal atrophy and 18-flourodeoxy-glucose positron emission tomography showed left anterior temporal and posterior frontal (premotor) hypometabolism. Autopsy revealed a mixed tauopathy (argyrophilic grain disease) and transactive response-DNA-binding-protein-43 proteinopathy. Dual pathologies may explain the difficulty classifying some PPA patients and recognizing this will be important as new imaging techniques (particularly tau-positron emission tomography) are introduced and patients begin enrollment in clinical trials targeting the underlying proteinopathy.     

Primary progressive aphasia and Pick complex

Ten autopsied patients from a prospectively followed, clinically defined, neuropsychologically and radiologically documented cohort with primary progressive aphasia were histologically characterized. All were variants of frontotemporal degeneration (Pick complex): Pick body dementia, n=3, corticobasals degeneration (CBD), n=4, and tau and synuclein negative ubiquitinated inclusions of the motor neuron disease type, n=3. All shared superficial cortical spongiosis, neuronal loss, and gliosis. Although most patients had fluent anomic aphasia at onset, all progressed to a nonfluent or mute state. Comprehension, episodic memory, and activities of daily living were initially preserved. Three cases with Pick body dementia had verbal apraxia and stuttering at onset. Two of the patients with CBD pathology were older than the average primary progressive aphasia (PPA). All patients developed secondary syndromes either of frontotemporal dementia (FTD) and/or extrapyramidal-apraxic manifestations (CBD). By the time autopsy was obtained, the pathology appeared outside the language areas. Progressive aphasias secondary to Alzheimer's disease (AD) were excluded on the basis of early loss of memory and comprehension.Rather than the previously emphasized histological heterogeneity, clinically probable PPA has a predictive value of a group of related pathologies, collectively named frontotemporal degeneration, or Pick complex. This series of autopsied cases provides evidence for the clinical and pathological overlap of PPA with FTD and CBD, and contributes to the diagnostic and neuropsychological definition of PPA.     

Analysis of Clinical and Neuroimaging Course of Four Patients with Left Side Dominant Fronto-temporal Lobar Atrophy

Background : Patients with left side dominant fronto-temporal lobar atrophy, as an example of primary progressive aphasia (PPA), are occasionally recognized. The concept of PPA is based on symptomatology. The aim of the present study was to investigate the clinical course and follow-up neuroimaging in patients with left side dominant atrophy, especially, during the incipient stage.
Methods : The subjects consist of four right-handed patients showing left side dominant fronto-temporal lobar atrophy on brain computed tomography or magnetic resonance imaging. They were analyzed using changes in clinical symptoms, electroencephalopathy (EEG), and neuroimaging course within a few years of diagnosis.
Results : Three of four patients had symptoms of PPA incipiently. The neuroimaging of three patients revealed a reduction in the asymmetrical anterior temporal gyri including the hippocampus on the left and progressed to bilateral fronto-temporal lobar atrophy within a few years.
Conclusion : One patient was clinically diagnosed as having Pick's disease, and three patients had probable Alzheimer's disease (AD), based on the clinical course and the findings of EEG and brain neuroimaging including single photon emission computed tomography (SPECT). These results suggest the possibilities that the patients with PPA may eventually develop AD. Moreover we confirmed that patients with left side dominant atrophy may generally progress to bilateral fronto-temporal lobar atrophy within a few years.     

Distinguishing logopenic from semantic & nonfluent variant primary progressive aphasia: Patterns of linguistic and behavioral correlations

While language characteristics of logopenic variant primary progressive aphasia (lvPPA) are well-defined, behavioral characteristics are less understood. We investigated correlations between language and behavioral scores across three variants of primary progressive aphasia (PPA) and found language performance and behavioral disturbances are correlated in lvPPA, but not other PPA subtypes. Results suggest that unlike other PPA variants, patients diagnosed with lvPPA do not develop negative behaviors until language deficits are severe. This is consistent with the underlying neuropathology of lvPPA, Alzheimer's Disease. Such findings are crucial to clinical prognosis, especially when considering the progressive nature of this disease.