References of "Perani, D"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailNeural correlates of anosognosia for cognitive impairment in Alzheimer's disease
Salmon, Eric ULg; Perani, D.; Herholz, K. et al

in Human Brain Mapping (2006), 27(7), 588-597

We explored the neural substrate of anosognosia for cognitive impairment in Alzheimer's disease (AD). Two hundred nine patients with mild to moderate dementia and their caregivers assessed patients ... [more ▼]

We explored the neural substrate of anosognosia for cognitive impairment in Alzheimer's disease (AD). Two hundred nine patients with mild to moderate dementia and their caregivers assessed patients' cognitive impairment by answering a structured questionnaire. Subjects rated 13 cognitive domains as not impaired or associated with mild, moderate, severe, or very severe difficulties, and a sum score was calculated. Two measures of anosognosia were derived. A patient's self assessment, unconfounded by objective measurements of cognitive deficits such as dementia severity and episodic memory impairment, provided an estimate of impaired self-evaluative judgment about cognition in AD. Impaired self-evaluation was related to a decrease in brain metabolism measured with 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in orbital prefrontal cortex and in medial temporal structures. In a cognitive model of anosognosia, medial temporal dysfunction might impair a comparison mechanism between current information on cognition and personal knowledge. Hypoactivity in orbitofrontal cortex may not allow AD patients to update the qualitative judgment associated with their impaired cognitive abilities. Caregivers perceived greater cognitive impairments than patients did. The discrepancy score between caregiver's and patient's evaluations, an other measure of anosognosia, was negatively related to metabolic activity located in the temporoparietal junction, consistent with an impairment of self-referential processes and perspective taking in AD. [less ▲]

Detailed reference viewed: 40 (5 ULg)
See detailHeterogeneity of brain glucose metabolism in mild cognitive impairment and clinical progression to Alzheimer disease
Anchisi, D.; Borroni, B.; Franceschi, M. et al

in Archives of Neurology (2005), 62(11), 1728-1733

Background: Subjects with amnesic mild cognitive impairment (aMCI) may include patients at high risk for progression to Alzheimer disease (AD) and a population with different underlying pathologic ... [more ▼]

Background: Subjects with amnesic mild cognitive impairment (aMCI) may include patients at high risk for progression to Alzheimer disease (AD) and a population with different underlying pathologic conditions. Objective: To evaluate the potential roles of positron emission tomography with fluodeoxyglucose F 18 ((18)FDG-PET) and memory scores in identifying subjects with aMCI and in predicting progression to dementia. Design, Setting, and Patients: Sixty-seven patients at European centers for neurologic and AD care who were diagnosed as having aMCI each underwent an extensive clinical and neuropsychological examination and an (18)FDG-PET study. Forty-eight subjects were followed up periodically for at least I year, and progression to dementia was evaluated. Main Outcome Measures: Brain glucose metabolism and memory scores. Results: Fourteen subjects with aMCI who converted to AD within 1 year showed bilateral hypometabolism in the inferior parietal, posterior cingulate, and medial temporal cortex. Subjects with "stable" aMCI presented with hypometabolism in the dorsolateral frontal cortex. The severity of memory impairment, as evaluated by the California Verbal Learning Test-Long Delay Free Recall scores, correlated with the following brain metabolic patterns: scores less than 7 were associated with a typical (18)FDG-PET AD pattern, and scores of 7 or higher were associated with hypornetabolism in the dorsolateral frontal cortex and no progression to AD. Conclusion: These data provide evidence for clinical and functional heterogeneity among subjects with aMCI and suggest that (18)FDG-PET findings combined with memory scores may be useful in predicting short-term conversion to AD. [less ▲]

Detailed reference viewed: 18 (0 ULg)
Full Text
Peer Reviewed
See detailAnosognosia in very mild Alzheimer's disease but not in mild cognitive impairment
Kalbe, E.; Salmon, Eric ULg; Perani, D. et al

in Dementia & Geriatric Cognitive Disorders (2005), 19(5-6), 349-356

Objective: To study awareness of cognitive dysfunction in patients with very mild Alzheimer's disease (AD) and subjects with mild cognitive impairment (MCI). Methods: A complaint interview covering 13 ... [more ▼]

Objective: To study awareness of cognitive dysfunction in patients with very mild Alzheimer's disease (AD) and subjects with mild cognitive impairment (MCI). Methods: A complaint interview covering 13 cognitive domains was administered to 82 AD and 79 MCI patients and their caregivers. The patient groups were comparable according to age and education, and Mini Mental State Examination (MMSE) scores were ≥ 24 in all cases. The discrepancy between the patients' and caregivers' estimations of impairments was taken as a measure of anosognosia. Results: Self-reports of cognitive difficulties were comparable for AD and MCI patients. However, while in comparison to caregivers MCI patients reported significantly more cognitive impairment (p < 0.05), AD patients complained significantly less cognitive dysfunctions (p < 0.001). Conclusions: While most MCI patients tend to overestimate cognitive deficits when compared to their caregiver's assessment, AD patients in early stages of disease underestimate cognitive dysfunctions. Anosognosia can thus be regarded as a characteristic symptom at a stage of very mild AD (MMSE ≥ 24) but not MCI. Accordingly, medical history even in mildly affected patients should always include information from both patient and caregiver. Copyright (C) 2005 S. Karger AG, Basel. [less ▲]

Detailed reference viewed: 44 (2 ULg)
Full Text
Peer Reviewed
See detailMCI conversion to dementia and the APOE genotype : A prediction study with FDG-PET
Mosconi, L.; Perani, D.; Sorbi, S. et al

in Neurology (2004), 63(12), 2332-2340

Objectives: To investigate whether the combination of fluoro-2-deoxy-D-glucose (FDG) PET measures with the APOE genotype would improve prediction of the conversion from mild cognitive impairment (MCI) to ... [more ▼]

Objectives: To investigate whether the combination of fluoro-2-deoxy-D-glucose (FDG) PET measures with the APOE genotype would improve prediction of the conversion from mild cognitive impairment (MCI) to Alzheimer disease ( AD). Method: After 1 year, 8 of 37 patients with MCI converted to AD (22%). Differences in baseline regional glucose metabolic rate (rCMRglc) across groups were assessed on a voxel-based basis using a two-factor analysis of variance with outcome (converters [n = 8] vs nonconverters [n = 29]) and APOE genotype (E4 carriers [E4+] [n = 16] vs noncarriers [E4-] [n = 21]) as grouping factors. Results were considered significant at p < 0.05, corrected for multiple comparisons. Results: All converters showed reduced rCMRglc in the inferior parietal cortex (IPC) as compared with the nonconverters. Hypometabolism in AD-typical regions, that is, temporoparietal and posterior cingulate cortex, was found for the E4+ as compared with the E4- patients, with the E4+/converters (n = 5) having additional rCMRglc reductions within frontal areas, such as the anterior cingulate (ACC) and inferior frontal (IFC) cortex. For the whole MCI sample, IPC rCMRglc predicted conversion to AD with 84% overall diagnostic accuracy (p = 0.003). Moreover, ACC and IFC rCMRglc improved prediction for the E4+ group, yielding 100% sensitivity, 90% specificity, and 94% accuracy (p < 0.0005), thus leading to an excellent discrimination. Conclusion: Fluoro-2-deoxy-D-glucose-PET measures may improve prediction of the conversion to Alzheimer disease, especially in combination with the APOE genotype. [less ▲]

Detailed reference viewed: 26 (0 ULg)
Full Text
Peer Reviewed
See detailDiscrimination between Alzheimer dementia and controls by automated analysis of multicenter FDG PET
Herholz, K.; Salmon, Eric ULg; Perani, D. et al

in Neuroimage (2002), 17(1), 302-316

A new diagnostic indicator of FDG PET scan abnormality, based on age-adjusted t statistics and an automated voxel-based procedure, is presented and validated in a large data set comprising 110 normal ... [more ▼]

A new diagnostic indicator of FDG PET scan abnormality, based on age-adjusted t statistics and an automated voxel-based procedure, is presented and validated in a large data set comprising 110 normal controls and 395 patients with probable Alzheimer's disease (AD) that were studied in eight participating centers. The effect of differences in spatial resolution of PET scanners was minimized effectively by filtering and masking. In controls FDG uptake declined significantly with age in anterior cingulate and frontolateral perisylvian cortex. In patients with probable AD decline of FDG uptake in posterior cingulate, temporoparietal, and prefrontal association cortex was related to dementia severity. These effects were clearly distinct from age effects in controls, suggesting that the disease process of AD is not related to normal aging. Women with probable AD had significantly more frontal metabolic impairment than men. The new indicator of metabolic abnormality in AD-related regions provided 93% sensitivity and specificity for distinction of mild to moderate probable AD from normals, and 84% sensitivity at 93% specificity for detection of very mild probable AD (defined by Mini Mental Score 24 or better). All regions related to AD severity were already affected in very mild AD, suggesting that all vulnerable areas are affected to a similar degree already at disease onset. Ventromedial frontal cortex was also abnormal. In conclusion, automated analysis of multicenter FDG PET is feasible, provides insights into AD pathophysiology, and can be used potentially as a sensitive biomarker for early AD diagnosis. (C) 2002 Elsevier Science (USA). [less ▲]

Detailed reference viewed: 34 (2 ULg)
Peer Reviewed
See detailImpairment of neocortical metabolism predicts progression in Alzheimer's disease
Herholz, K.; Nordberg, A.; Salmon, Eric ULg et al

in Dementia & Geriatric Cognitive Disorders (1999), 10(6), 494-504

Studied prediction of progression rates of Alzheimer's disease (AD) in a prospective multicenter cohort study of 186 patients (mean age 63.2 yrs) with possible or probable AD, mostly with presenile onset ... [more ▼]

Studied prediction of progression rates of Alzheimer's disease (AD) in a prospective multicenter cohort study of 186 patients (mean age 63.2 yrs) with possible or probable AD, mostly with presenile onset. In a cross-sectional analysis at entry, impairment of glucose metabolism in temporoparietal or frontal association areas measured with positron emission tomography was significantly associated with dementia severity, clinical classification as possible vs probable AD, presence of multiple cognitive deficits and history of progression. A prospective longitudinal analysis showed a significant association between initial metabolic impairment and subsequent clinical deterioration. In patients with mild cognitive deficits at entry, the risk of deterioration was up to 4.7 times higher if the metabolism was severely impaired than with mild or absent metabolic impairment. [less ▲]

Detailed reference viewed: 22 (2 ULg)