Decreased Thalamic Monoamine Availability in Drug-Induced Parkinsonism

2021 ◽  
Author(s):  
Yoon-Sang Oh ◽  
Sang-Won Yoo ◽  
Chul Hyoung Lyoo ◽  
Joong-Seok Kim
Keyword(s):  
Ventral Striatum ◽  
Brain Magnetic Resonance Imaging ◽  
Imaging Biomarker ◽  
Resonance Imaging ◽  
Drug Induced ◽  
Dopamine Transporter Imaging ◽  
Standardized Uptake Values ◽  
Positron Emission ◽  
Volume Of Interest ◽  
Normal Controls

Abstract Drug-induced parkinsonism (DIP) is caused by a dopamine receptor blockade and is a major cause of misleading diagnosis of Parkinson’s disease (PD). Striatal dopamine activity has been investigated widely in DIP; however, most studies with dopamine transporter imaging have focused on the clinical characteristics and prognosis. This study investigated differences in striatal subregional monoamine availability among patients with DIP, normal controls, and patients with early PD. Thirty-five DIP patients, the same number of age-matched PD patients, and 46 healthy controls were selected for this study. Parkinsonian motor status was examined. Brain magnetic resonance imaging and positron emission tomography with 18F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane were performed, and the regional standardized uptake values were analyzed with a volume-of-interest template and compared among the groups. Females were more predominant in the DIP group than in the PD group. Parkinsonian motor symptoms were similar in the DIP and PD groups. Monoamine availability in the thalamus of the DIP group was lower than that of the normal controls and similar to that of the PD group. In other subregions (putamen, globus pallidus, and ventral striatum), monoamine availability in the DIP group and normal controls did not differ and was higher than that in the PD group. These findings suggest that low monoamine availability in the thalamus could be an imaging biomarker of DIP.

scholarly journals Imaging of brain oxygenation with magnetic resonance imaging: A validation with positron emission tomography in the healthy and tumoural brain

2016 ◽  
Vol 37 (7) ◽  
pp. 2584-2597 ◽  
Author(s):  
Samuel Valable ◽  
Aurélien Corroyer-Dulmont ◽  
Ararat Chakhoyan ◽  
Lucile Durand ◽  
Jérôme Toutain ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Positron Emission Tomography ◽  
Magnetic Resonance ◽  
High Sensitivity ◽  
Emission Tomography ◽  
Imaging Biomarker ◽  
C6 Glioma Cells ◽  
Resonance Imaging ◽  
Positron Emission ◽  
The Brain

The partial pressure in oxygen remains challenging to map in the brain. Two main strategies exist to obtain surrogate measures of tissue oxygenation: the tissue saturation studied by magnetic resonance imaging (StO2-MRI) and the identification of hypoxia by a positron emission tomography (PET) biomarker with 3-[18F]fluoro-1-(2-nitro-1-imidazolyl)-2-propanol ([18F]-FMISO) as the leading radiopharmaceutical. Nonetheless, a formal validation of StO2-MRI against FMISO-PET has not been performed. The objective of our studies was to compare the two approaches in (a) the normal rat brain when the rats were submitted to hypoxemia; (b) animals implanted with four tumour types differentiated by their oxygenation. Rats were submitted to normoxic and hypoxemic conditions. For the brain tumour experiments, U87-MG, U251-MG, 9L and C6 glioma cells were orthotopically inoculated in rats. For both experiments, StO2-MRI and [18F]-FMISO PET were performed sequentially. Under hypoxemia conditions, StO2-MRI revealed a decrease in oxygen saturation in the brain. Nonetheless, [18F]-FMISO PET, pimonidazole immunohistochemistry and molecular biology were insensitive to hypoxia. Within the context of tumours, StO2-MRI was able to detect hypoxia in the hypoxic models, mimicking [18F]-FMISO PET with high sensitivity/specificity. Altogether, our data clearly support that, in brain pathologies, StO2-MRI could be a robust and specific imaging biomarker to assess hypoxia.

scholarly journals Machine Learning for Diagnosis of AD and Prediction of MCI Progression From Brain MRI Using Brain Anatomical Analysis Using Diffeomorphic Deformation

2021 ◽  
Vol 11 ◽  
Author(s):  
Ali Haidar Syaifullah ◽  
Akihiko Shiino ◽  
Hitoshi Kitahara ◽  
Ryuta Ito ◽  
Manabu Ishida ◽  
...  
Keyword(s):  
Machine Learning ◽  
Brain Structure ◽  
High Performance ◽  
Brain Mri ◽  
Model Performance ◽  
Imaging Biomarker ◽  
Support Vector ◽  
Resonance Imaging ◽  
Positron Emission ◽  
The Brain

Background: With the growing momentum for the adoption of machine learning (ML) in medical field, it is likely that reliance on ML for imaging will become routine over the next few years. We have developed a software named BAAD, which uses ML algorithms for the diagnosis of Alzheimer's disease (AD) and prediction of mild cognitive impairment (MCI) progression.Methods: We constructed an algorithm by combining a support vector machine (SVM) to classify and a voxel-based morphometry (VBM) to reduce concerned variables. We grouped progressive MCI and AD as an AD spectrum and trained SVM according to this classification. We randomly selected half from the total 1,314 subjects of AD neuroimaging Initiative (ADNI) from North America for SVM training, and the remaining half were used for validation to fine-tune the model hyperparameters. We created two types of SVMs, one based solely on the brain structure (SVMst), and the other based on both the brain structure and Mini-Mental State Examination score (SVMcog). We compared the model performance with two expert neuroradiologists, and further evaluated it in test datasets involving 519, 592, 69, and 128 subjects from the Australian Imaging, Biomarker & Lifestyle Flagship Study of Aging (AIBL), Japanese ADNI, the Minimal Interval Resonance Imaging in AD (MIDIAD) and the Open Access Series of Imaging Studies (OASIS), respectively.Results: BAAD's SVMs outperformed radiologists for AD diagnosis in a structural magnetic resonance imaging review. The accuracy of the two radiologists was 57.5 and 70.0%, respectively, whereas, that of the SVMst was 90.5%. The diagnostic accuracy of the SVMst and SVMcog in the test datasets ranged from 88.0 to 97.1% and 92.5 to 100%, respectively. The prediction accuracy for MCI progression was 83.0% in SVMst and 85.0% in SVMcog. In the AD spectrum classified by SVMst, 87.1% of the subjects were Aβ positive according to an AV-45 positron emission tomography. Similarly, among MCI patients classified for the AD spectrum, 89.5% of the subjects progressed to AD.Conclusion: Our ML has shown high performance in AD diagnosis and prediction of MCI progression. It outperformed expert radiologists, and is expected to provide support in clinical practice.

scholarly journals Diogenes syndrome in dementia: a case report

BJPsych Open ◽  
2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Luca Sacchi ◽  
Emanuela Rotondo ◽  
Sara Pozzoli ◽  
Alessio Fiorentini ◽  
Giuseppina Schinco ◽  
...  
Keyword(s):  
Verbal Fluency ◽  
Brain Magnetic Resonance Imaging ◽  
Superior Temporal Gyrus ◽  
Amyloid Pet ◽  
Resonance Imaging ◽  
Mental Functioning ◽  
Diagnostic Challenge ◽  
Positron Emission ◽  
Diogenes Syndrome ◽  
State Examination

Background Diogenes syndrome is a neurobehavioural syndrome characterised by domestic squalor, hoarding and lack of insight. It is an uncommon but high-mortality condition, often associated with dementia. Aims To describe the clinical features and treatment of Diogenes syndrome secondary to behavioural variant frontotemporal dementia (bvFTD). Method We describe a case of bvFTD in a 77-year-old man presenting with Diogenes syndrome. Results The patient's medical and psychiatric histories were unremarkable, but in recent years he had begun packing his flat with ‘art pieces’. Mental state examination revealed confabulation and more structured delusions. Neuropsychological evaluation outlined an impairment in selective attention and letter verbal fluency, but no semantic impairment, in the context of an overall preserved mental functioning. Brain magnetic resonance imaging and positron emission tomography (PET) with fluorodeoxyglucose showed mild bilateral temporo-insular atrophy and hypometabolism in the left-superior temporal gyrus respectively. An amyloid PET scan and genetic analysis covering the dementia spectrum were normal. A diagnosis of bvFTD was made. Conclusions The clinical framing of behavioural symptoms of dementia such as hoarding poses a diagnostic challenge. This case illustrates the importance of a deeper understanding of Diogenes syndrome, leading to timelier diagnosis and effective therapeutic strategies.

Reversible MRI Abnormalities in a Patient with Recurrent Status Migrainosus

Cephalalgia ◽  
2009 ◽  
Vol 29 (6) ◽  
pp. 687-690 ◽  
Author(s):  
S Gentile ◽  
I Rainero ◽  
D Daniele ◽  
E Binello ◽  
W Valfrè ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Positron Emission Tomography ◽  
Magnetic Resonance ◽  
Migraine Without Aura ◽  
Cerebral Oedema ◽  
Brain Magnetic Resonance Imaging ◽  
Emission Tomography ◽  
Resonance Imaging ◽  
Positron Emission ◽  
Status Migrainosus

Status migrainosus is a condition characterized by a migraine attack causing disability, with or without aura, lasting for > 72 h. The pathophysiological mechanisms underlying this complication of migraine remain a matter of debate. We describe a migraine without aura patient who presented two episodes of status migrainosus associated with recurrent and reversible brain magnetic resonance imaging abnormalities. These abnormalities, confirmed also by positron emission tomography, suggest that status migrainosus can be associated with a condition of vasogenic cerebral oedema.

scholarly journals Dilated Virchow-Robin Space and Dopamine Transporter Imaging in the Striatum of Patients with Parkinsonism

2015 ◽  
Vol 42 (4) ◽  
pp. 248-254 ◽  
Author(s):  
Dokyung Lee ◽  
Il Ki Hong ◽  
Tae-Beom Ahn
Keyword(s):  
Dopamine Transporter ◽  
Clinical Status ◽  
Brain Magnetic Resonance Imaging ◽  
Caudate Nuclei ◽  
Dopamine Transporter Imaging ◽  
Positron Emission ◽  
Mini Mental Status Examination ◽  
The Relationship ◽  
Virchow Robin Space

AbstractObjective: The radiological and clinical significance of a dilated Virchow-Robin space (dVRS) in the striatum (STR) remains unclear. We investigated the role of dVRS in STR on parkinsonism and dopamine transporter positron emission tomography (DaT-PET) findings. Methods: Patients with parkinsonism who underwent both brain magnetic resonance imaging and DaT-PET were included. Clinical status was evaluated by Hoehn and Yahr (HY) stage, Korean-Mini Mental Status Examination (K-MMSE), Montreal Cognitive Assessment Korea (MoCA-K), and Frontal Assessment Battery (FAB). dVRS was assessed by semi-quantitative and quantitative scales in each of the three segments of STR (caudate nuclei, anterior and posterior putamen) and was expressed as a dVRS score. DaT-PET was qualitatively assessed as either normal or abnormal in each segment. The relationship between dVRS and DaT-PET abnormality (ab-DaT-PET) was designated in each segment as either concordant or discordant. A concordant segment was defined by the presence of dVRS with ab-DaT-PET [Concordance rate (CR)=number of concordant segments/number of concordant and discordant segments]. Results: Eleven patients were included. There was no significant correlation between the presence of dVRS and ab-DaT-PET. The mean CR was 0.39. CR was not significantly correlated with any clinical or neuroimaging scales. The dVRS score was significantly correlated with K-MMSE, MoCA-K, and FAB (r=−0.675, −0.847, and −0.868, respectively) but not with HY stage. Conclusion: dVRS in STR played no significant role on dopaminergic innervation revealed by DaT-PET and made little contribution to clinical parkinsonism; however, it was correlated with cognitive impairment.

scholarly journals Brain Glucose Metabolism in Cerebral Amyloid Angiopathy

Stroke ◽  
2021 ◽  
Vol 52 (4) ◽  
pp. 1478-1482
Author(s):  
Sébastien Bergeret ◽  
Mathieu Queneau ◽  
Mathieu Rodallec ◽  
Brigitte Landeau ◽  
Gaël Chetelat ◽  
...  
Keyword(s):  
Brain Magnetic Resonance Imaging ◽  
Standardized Uptake Value ◽  
Regions Of Interest ◽  
Emission Tomography ◽  
Amyloid Angiopathy ◽  
Resonance Imaging ◽  
Cortical Areas ◽  
Symptomatic Intracerebral Hemorrhage ◽  
Positron Emission ◽  
Cerebral Amyloid

Background and Purpose: The in vivo diagnosis of cerebral amyloid angiopathy (CAA) is currently based on the Boston criteria, which largely rely on hemorrhagic features on brain magnetic resonance imaging. Adding to these criteria 18 F-fluoro-deoxy-D-glucose (FDG) positron emission tomography, a widely available imaging modality, might improve their accuracy. Here we tested the hypothesis that FDG uptake is reduced in posterior cortical areas, particularly the primary occipital cortex, which pathologically bear the brunt of vascular Aβ deposition. Methods: From a large memory clinic database, we retrospectively included all patients in whom both brain magnetic resonance imaging and FDG positron emission tomography had been obtained as part of routine clinical care and who fulfilled the Boston criteria for probable CAA. None had a history of symptomatic intracerebral hemorrhage. FDG data processing involved (1) spatial normalization to the Montreal Neurology Institute/International Consortium for Brain Mapping 152 space and (2) generation of standardized FDG uptake (relative standardized uptake value; relative to the pons). The relative standardized uptake value data obtained in 13 regions of interest sampling key cortical areas and the cerebellum were compared between the CAA and age-matched control groups using 2 separate healthy subject databases and image-processing pipelines. The presence of significant hypometabolism (2-tailed P <0.05) was assessed for the bilaterally averaged regions-of-interest relative standardized uptake values. Results: Fourteen patients fulfilling the Boston criteria for probable CAA (≥2 exclusively lobar microbleeds) were identified. Significant hypometabolism ( P range, 0.047 to <0.0001) consistently affected the posterior cortical areas, including the superior and inferior parietal, primary visual, lateral occipital, lateral temporal, precuneus, and posterior cingulate regions of interest. The anterior cortical areas were marginally or not significantly hypometabolic, and the cerebellum was spared. Conclusions: Supporting our hypothesis, significant glucose hypometabolism predominantly affected posterior cortical regions, including the visual cortex. These findings from a small sample may have diagnostic implications but require replication in larger prospective studies. In addition, whether they generalize to CAA-related symptomatic intracerebral hemorrhage warrants specific studies.

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