Eleni Dedousi

Evaluation of Dopaminergic Function in Frontotemporal Dementia Using 123I-FP-CIT Single Photon Emission Computed Tomography

Extrapyramidal symptoms are observed in frontotemporal dementia (FTD). 123I-FP-CIT (DaT scan) single photon emission computed tomography (SPECT) can detect loss of presynaptic dopamine transporters in the striatum. We aimed to evaluate the dopaminergic status of the striatum in patients with FTD using DaT scan. Seven patients (age range 65–76 years), who fulfilled the Neary criteria and in whom the diagnosis of FTD was confirmed by hexamethylpropyleneamine oxime SPECT, were included in the study. The severity of the extrapyramidal symptoms was evaluated by the motor part of the Unified Parkinson’s Disease Rating Scale (UPDRS). SPECT using 123I-FP-CIT was done. A (region – occipital)/occipital ratio was calculated for the striatum, putamen and caudate nucleus. The results were compared with those of the 7 age-matched normal controls. The uptake of the radiotracer in the right and left striatum was reduced to 62% (p = 0.000) and 68% (p = 0.000), respectively, compared to controls. The motor UPDRS score of the patients with FTD showed a negative correlation to the uptake of the radiotracer. The presynaptic dopamine transporter in FTD is impaired, related to the severity of the extrapyramidal symptoms. Since an effective treatment for FTD is still to be established, there is a need for evaluating the efficacy of dopaminergic drugs.

Plasma Levels of Amyloid β1-42 Are Independent of Neuronal Function in Alzheimer's Disease

The aggregation of amyloid-beta42 (Abeta42) constitutes one of the major pathogenic events in Alzheimers disease (AD), and the study of regional cerebral blood flow (rCBF), using single photon emission computed tomography (SPECT), aids the diagnosis of AD. In this study, we evaluated whether there was a correlation between rCBF in brain regions and plasma levels of Abeta1-42 in AD. 29 patients (mean age 71 +/- 9) with a diagnosis of AD who fulfilled NINCDS-ADRDA criteria with a mean Mini-Mental Status Examination score of 15 +/- 9 and 16 normal controls (mean age 64 +/- 8) underwent SPECT brain imaging with hexamethylpropylene amine oxime, and semiquantitative analysis of rCBF was performed. Plasma samples were collected the same day of the SPECT and plasma Abeta1-42 measured by ELISA. A significant reduction of rCBF was observed in most regions in AD compared to controls, whereas mean plasma Abeta42 did not differ between the two groups. There was no correlation between rCBF in any region and plasma Abeta42 nor any correlations between gender, age, and severity with plasma levels of Abeta42. Since rCBF is coupled to neuronal activity, we conclude that plasma Abeta1-42 concentration is independent of neuronal function in every single region of the brain.

High plasma Amyloid β42 and P-tau in mild cognitive impairment as risk factors of the disease

Background Patients with mild cognitive impairment (MCI) is reported to develop Alzheimers disease (AD) at the rate of 12% per year, greatly exceeding the 1% to 2% incidence of normal controls. Several studies have shown an increase in plasma Aβ42 in MCI compared to normal and AD patients. The efficiency of Aβ peptides elimination in earlier stages of AD has proven in animal models. We found no study measuring phospho-tau (p-tau) level in plasma.

Right inferior parietal region hypoperfusion as a reflection of anosognosia in dementia

Materials and methods Seventy three patients in mild or moderate stage of dementia of different types are included in the study. After a clinical interview with the patients and their relatives, the patients were divided into two groups: a) anosognosia consisted of 41 patients (mean age 73±11 y) (mean MMSE 17±5), who were not aware of their disease. b) no anosognosia including 32 patients (mean age 71±8 y) (mean MMSE 23±4), who had full awareness of their disorder. The patients underwent HMPAO single photon emission computed tomography (SPECT) and rCBF was measured using region of interest (ROI) in right and left prefrontal, frontal, superior and inferior parietal, lateral and medial temporal, occipital and Posterior cingulate.

The contribution of brain perfusion SPECT and magnetic resonance imaging in early diagnosis of neurodegenerative dementia

Materials and methods 107 patients underwent MRI and SPECT using HMPAO at the Department of Radiology and Nuclear Medicine of AHEPA University Hospital. Our patients based on clinical diagnosis were categorized into 3 groups: a) Neurodegenerative dementia (ND) consisted of 61 patients (mean age71±9) with Alzheimers disease (AD), frontotemporal dementia (FTD), dementia with Lewy bodies (DLB) and mixed dementia, b) Vascular cognitive impairment VCI consisted 27 patients (mean age 70±7), and c) Normal group included 19 persons (mean age 64±7).

Plasma level of Amyloid β42 Is independent of neuronal function in Alzheimer's Disease

Background Amyloid β42 (Aβ42) accumulation is said to be one of the major pathogenic events in Alzheimers disease (AD). Regional cerebral blood flow (rCBF) studies using SPECT aid the diagnosis of AD. We evaluated any correlation between rCBF in different regions of the brain and plasma Aβ1-42 in patients with AD. To date we have found no study in this concern. Any correlation between age and sex of the subjects with plasma Aβ42 and rCBF is studied too.