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Objectifs L’anarthrie a ete decrite dans de nombreuses pathologies neurologiques, de facon isolee ou en association a une aphasie. Toutefois, l’anarthrie dans sa forme chronique peut egalement etre la seule manifestation d’un syndrome neuro-degeneratif rare, nomme anarthrie primaire progressive (AnPP). L’objectif principal de l’etude est la caracterisation en neuro-imagerie (TEP/TDM 18FDG et IRM) et au point de vue clinique de l’AnPP. Materiels et methodes Les patients avaient un diagnostic d’AnPP pose apres examen neurologique, neuropsychologique et orthophonique. Les criteres d’exclusion comprenaient la presence d’une aphasie ou des antecedents neurologiques. Des acquisitions TEP/TDM 18FDG et des IRM cerebrales (sequences T1, T2, diffusion, FLAIR) etaient realisees et comparees a un groupe de sujets temoins issu de la base ADNI, apparies pour l’âge. Les analyses statistiques etaient realisees avec le logiciel SPM8. Resultats Cinq patients presentant les criteres diagnostiques d’AnPP etaient inclus, d’âge moyen 70,4, sex-ratio F/M de 4/1. L’examen clinique montrait une anarthrie, une apraxie-oro-faciale, une dysarthrie et des troubles de la deglutition, d’intensite variable selon les sujets. Les analyses en 18FDG montraient un hypometabolisme des aires motrice supplementaire et premotrice gauches (parties mediane et laterale de l’aire de Broadman 6). En IRM, il existait une atrophie corticale significative dans les memes zones. Les marqueurs biologiques du LCR etaient normaux. Conclusions Notre etude (portant seulement sur 5 patients du fait du caractere rare de la pathologie), suggere l’existence de l’AnPP comme pathologie neurodegenerative a part entiere. Elle se caracterise par des signes cliniques et des patterns 18FDG et IRM specifiques, impliquant directement les aires motrice supplementaire et premotrice gauches, confirmant ainsi les hypotheses formulees dans de precedents travaux.

Objective: To determine the value of clinical assessment, MRI cortical thickness and [18FDG]-PET metabolism in predicting pathophysiology defined by cerebro-spinal fluid (CSF) biomarkers in patients suffering of predominant language difficulties of a neurodegenerative origin. Background Aphasia is common in neurodegenerative diseases, and may be the main symptom, as in all 3 variants of progressive primary aphasia (PPA). Some studies have tried to predict the underlying pathology. Each variant is associated with a predominant histopathology, but it can only reflect group-wide probabilities. We decided to consider the underlying pathology (Alzheimer9s (AD) or non-AD), and check subsequently if any clinical, structural or metabolic differences could emerge between both defined groups. Design/Methods: 26 aphasic patients underwent comprehensive language and neuropsychological assessments, structural MRI, [18FDG]-PET, and CSF analysis; eleven age-matched healthy controls (HC) underwent the same examinations except for the lumbar puncture. Biomarkers in CSF allowed us to classify patients as AD or non-AD. Results: 11 subjects had biomarkers consistent with AD, leaving 15 in the non-AD group. Compared to the HC, language impairment was the main symptom for all patients. However, no differences between groups emerged in language assessments. AD patients exhibit more praxis and visuo-spatial difficulties compared to the non AD group. The difference was significant but less marked for memory. MRI showed more posterior and symmetric cortical thickness reduction in the AD group. No difference in the medial temporal lobe was observed between the two patients groups. Temporo-parietal hypometabolism was more marked in the AD group but no difference in frontal cortex was found. Conclusions: Language impairment is not a reliable predictor of pathology in our patients, though it is the main symptom. Clinical presentation seems to depend on anatomic damage sites more than the underlying pathology. Disclosure: Dr. Sagot has nothing to disclose. Dr. Saint-Aubert has nothing to disclose. Dr. Bezy has nothing to disclose. Dr. Mirabel has nothing to disclose. Dr. Payoux has nothing to disclose. Dr. Dumas has nothing to disclose. Dr. Vincent has nothing to disclose. Dr. Peran has nothing to disclose. Dr. Barbeau has nothing to disclose. Dr. Puel has nothing to disclose. Dr. Chollet has nothing to disclose. Dr. Pariente has nothing to disclose.

Purpose Florbetapir (AV-45) has been shown to be a reliable tool for assessing in vivo amyloid load in patients with Alzheimer’s disease from the early stages. However, nonspecific white matter binding has been reported in healthy subjects as well as in patients with Alzheimer’s disease. To avoid this issue, cortical quantification might increase the reliability of AV-45 PET analyses. In this study, we compared two quantification methods for AV-45 binding, a classical method relying on PET template registration (route 1), and a MRI-based method (route 2) for cortical quantification. Methods We recruited 22 patients at the prodromal stage of Alzheimer’s disease and 17 matched controls. AV-45 binding was assessed using both methods, and target-to-cerebellum mean global standard uptake values (SUVr) were obtained for each of them, together with SUVr in specific regions of interest. Quantification using the two routes was compared between the clinical groups (intragroup comparison), and between groups for each route (intergroup comparison). Discriminant analysis was performed. Results In the intragroup comparison, differences in uptake values were observed between route 1 and route 2 in both groups. In the intergroup comparison, AV-45 uptake was higher in patients than controls in all regions of interest using both methods, but the effect size of this difference was larger using route 2. In the discriminant analysis, route 2 showed a higher specificity (94.1 % versus 70.6 %), despite a lower sensitivity (77.3 % versus 86.4 %), and D-prime values were higher for route 2. Conclusion These findings suggest that, although both quantification methods enabled patients at early stages of Alzheimer’s disease to be well discriminated from controls, PET template-based quantification seems adequate for clinical use, while the MRI-based cortical quantification method led to greater intergroup differences and may be more suitable for use in current clinical research. Electronic supplementary material The online version of this article (doi:10.1007/s00259-013-2656-8) contains supplementary material, which is available to authorized users.

International audience; BACKGROUND: Florbetapir (AV-45) has been shown to be a reliable tool to assess amyloid load in patients with Alzheimer's disease (AD) at demential stages. Longitudinal studies also suggest that AV-45 has the ability to bind amyloid in the early stages of AD. In this study, we investigated AV-45 binding and its relation with cognitive performance in a group of patients at the prodromal stage of Alzheimer's disease, recruited according to strict inclusion criteria. METHODS: We recruited patients at the prodromal stage of AD and matched control subjects. AV-45 binding was assessed using an innovative extraction method allowing quantifying uptake in the cortex only. AV-45 uptake was compared between groups in the precuneus, posterior cingulate, anterior cingulate, and orbito-frontal regions. Correlations between AV-45 uptake and cognitive performance were assessed. RESULTS: Twenty-two patients and 17 matched control subjects were included in the study. We report a significant increase of cortical AV-45 uptake in the patients compared to the control subjects in all regions of interest. Specific correlations were found within the patient group between mean global amyloid cortical load and cognitive performance in three different memory tests. CONCLUSIONS: These findings suggest that at the prodromal stage of AD, memory decline is linked to an increase of cortical β-amyloid load.