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1.
Brain ; 146(1): 337-348, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36374264

RESUMO

Higher vascular disease burden increases the likelihood of developing dementia, including Alzheimer's disease. Better understanding the association between vascular risk factors and Alzheimer's disease pathology at the predementia stage is critical for developing effective strategies to delay cognitive decline. In this work, we estimated the impact of six vascular risk factors on the presence and severity of in vivo measured brain amyloid-beta (Aß) plaques in participants from the population-based Rotterdam Study. Vascular risk factors (hypertension, hypercholesterolaemia, diabetes, obesity, physical inactivity and smoking) were assessed 13 (2004-2008) and 7 years (2009-2014) prior to 18F-florbetaben PET (2018-2021) in 635 dementia-free participants. Vascular risk factors were associated with binary amyloid PET status or continuous PET readouts (standard uptake value ratios, SUVrs) using logistic and linear regression models, respectively, adjusted for age, sex, education, APOE4 risk allele count and time between vascular risk and PET assessment. Participants' mean age at time of amyloid PET was 69 years (range: 60-90), 325 (51.2%) were women and 190 (29.9%) carried at least one APOE4 risk allele. The adjusted prevalence estimates of an amyloid-positive PET status markedly increased with age [12.8% (95% CI 11.6; 14) in 60-69 years versus 35% (36; 40.8) in 80-89 years age groups] and APOE4 allele count [9.7% (8.8; 10.6) in non-carriers versus 38.4% (36; 40.8) to 60.4% (54; 66.8) in carriers of one or two risk allele(s)]. Diabetes 7 years prior to PET assessment was associated with a higher risk of a positive amyloid status [odds ratio (95% CI) = 3.68 (1.76; 7.61), P < 0.001] and higher standard uptake value ratios, indicating more severe Aß pathology [standardized beta = 0.40 (0.17; 0.64), P = 0.001]. Hypertension was associated with higher SUVr values in APOE4 carriers (mean SUVr difference of 0.09), but not in non-carriers (mean SUVr difference 0.02; P = 0.005). In contrast, hypercholesterolaemia was related to lower SUVr values in APOE4 carriers (mean SUVr difference -0.06), but not in non-carriers (mean SUVr difference 0.02). Obesity, physical inactivity and smoking were not related to amyloid PET measures. The current findings suggest a contribution of diabetes, hypertension and hypercholesterolaemia to the pathophysiology of Alzheimer's disease in a general population of older non-demented adults. As these conditions respond well to lifestyle modification and drug treatment, further research should focus on the preventative effect of early risk management on the development of Alzheimer's disease neuropathology.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Diabetes Mellitus , Hipercolesterolemia , Hipertensão , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Hipercolesterolemia/patologia , Tomografia por Emissão de Pósitrons , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/patologia , Encéfalo/patologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/patologia , Hipertensão/epidemiologia , Hipertensão/patologia , Obesidade/patologia
2.
J Craniofac Surg ; 34(1): 312-317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35949016

RESUMO

Implementation of the Utrecht Cranial Shape Quantificator (UCSQ) classification method on 3D photogrammetry in patients with different types of craniosynostosis is the aim of the present study. Five children (age <1 year) of every group of the common craniosynostoses (scaphocephaly, brachycephaly, trigonocephaly, right-sided and left-sided anterior plagiocephaly) were randomly included. The program 3-Matic (v13.0) was used to import and analyze the included 3dMD photos. Three external landmarks were placed. Using the landmarks, a base plane was created, as well as a plane 4 cm superior to the base plane. Using UCSQ, we created sinusoid curves of the patients, the resulting curves were analyzed and values were extracted for calculations. Results per patient were run through a diagnostic flowchart in order to determine correctness of the flowchart when using 3D photogrammetry. Each of the patients (n=25) of the different craniosynostosis subgroups is diagnosed correctly based on the different steps in the flowchart. This study proposes and implements a diagnostic approach of craniosynostosis based on 3D photogrammetry. By using a diagnostic flowchart based on specific characteristics for every type of craniosynostosis related to specific skull deformities, diagnosis can be established. All variables are expressed in number and are therefore objective.


Assuntos
Craniossinostoses , Plagiocefalia , Criança , Humanos , Lactente , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Crânio , Ossos Faciais , Fotogrametria/métodos
3.
Cleft Palate Craniofac J ; 60(10): 1273-1283, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538856

RESUMO

OBJECTIVE: Objective differentiation between unilateral coronal synostosis (UCS) and positional posterior plagiocephaly (PPP) based on 3D photogrammetry according to Utrecht Cranial Shape Quantificator (UCSQ). DESIGN: Retrospective study. SETTING: Primary craniofacial center. PATIENTS, PARTICIPANTS: Thirty-two unoperated patients (17 UCS; 15 PPP) (age < 1 year). INTERVENTIONS: Extraction of variables from sinusoid curves derived using UCSQ: asymmetry ratio forehead and occiput peak, ratio of gradient forehead and occiput peak, location forehead and occiput peak. MAIN OUTCOME MEASURE(S): Variables, derived using 3D photogrammetry, were analyzed for differentiation between UCS and PPP. RESULTS: Frontal peak was shifted to the right side of the head in left-sided UCS (mean x-value 207 [192-220]), and right-sided PPP (mean x-value 210 [200-216]), and to the left in right-sided UCS (mean x-value 161 [156-166]), and left-sided PPP (mean x-value 150 [144-154]). Occipital peak was significantly shifted to the right side of the head in left-sided PPP (mean x-value 338 [336-340]) and to the left in right-sided PPP (mean x-value 23 [14-32]). Mean x-value of occipital peak was 9 (354-30) in left- and 2 (350-12) in right-sided UCS. Calculated ratio of gradient of the frontal peak is, in combination with the calculated asymmetry ratio of the frontal peak, a distinctive finding. CONCLUSIONS: UCSQ objectively captures shape of synostotic and positional plagiocephaly using 3D photogrammetry, we therefore developed a suitable method to objectively differentiate UCS from PPP using radiation-free methods.


Assuntos
Craniossinostoses , Plagiocefalia não Sinostótica , Plagiocefalia , Humanos , Lactente , Plagiocefalia não Sinostótica/diagnóstico por imagem , Estudos Retrospectivos , Crânio , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Fotogrametria
4.
Alzheimer Dis Assoc Disord ; 36(4): 327-334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36445223

RESUMO

BACKGROUND: Intracranial stenosis (ICS) and brain amyloid-beta (Aß) have been associated with cognition and dementia. We aimed to investigate the association between ICS and brain Aß and their independent and joint associations with cognition. METHODS: We conducted a cross-sectional study of 185 patients recruited from a memory clinic. ICS was measured on 3-dimensional time-of-flight magnetic resonance angiography and defined as stenosis ≥50%. Brain Aß was measured with [ 11 C] Pittsburgh compound B-positron emission tomography imaging. Cognition was assessed with a locally validated neuropsychological battery. RESULTS: A total of 17 (9.2%) patients had ICS, and the mean standardized uptake value ratio was 1.4 (±0.4 SD). ICS was not significantly associated with brain Aß deposition. ICS was significantly associated with worse global cognition (ß: -1.26, 95% CI: -2.25; -0.28, P =0.013), executive function (ß: -1.04, 95% CI: -1.86; -0.22, P =0.015) and visuospatial function (ß: -1.29, 95% CI: -2.30; -0.27, P =0.015). Moreover, in ICS patients without dementia (n=8), the presence of Aß was associated with worse performance on visuomotor speed. CONCLUSIONS: ICS was significantly associated with worse cognition and showed interaction with brain Aß such that patients with both pathologies performed worse on visuomotor speed specifically in those without dementia. Further studies may clarify if ICS and brain Aß deposition indeed have a synergistic association with cognition.


Assuntos
Cognição , Demência , Humanos , Constrição Patológica , Estudos Transversais , Peptídeos beta-Amiloides , Encéfalo
5.
Dev Med Child Neurol ; 64(1): 118-124, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265076

RESUMO

AIM: To assess the relationship of surface area of the cerebral cortex to intracranial volume (ICV) in syndromic craniosynostosis. METHOD: Records of 140 patients (64 males, 76 females; mean age 8y 6mo [SD 5y 6mo], range 1y 2mo-24y 2mo) with syndromic craniosynostosis were reviewed to include clinical and imaging data. Two hundred and three total magnetic resonance imaging (MRI) scans were evaluated in this study (148 patients with fibroblast growth factor receptor [FGFR], 19 patients with TWIST1, and 36 controls). MRIs were processed via FreeSurfer pipeline to determine total ICV and cortical surface area (CSA). Scaling coefficients were calculated from log-transformed data via mixed regression to account for multiple measurements, sex, syndrome, and age. Educational outcomes were reported by syndrome. RESULTS: Mean ICV was greater in patients with FGFR (1519cm3 , SD 269cm3 , p=0.016) than in patients with TWIST1 (1304cm3 , SD 145cm3 ) or controls (1405cm3 , SD 158cm3 ). CSA was related to ICV by a scaling law with an exponent of 0.68 (95% confidence interval [CI] 0.61-0.76) in patients with FGFR compared to 0.81 (95% CI 0.50-1.12) in patients with TWIST1 and 0.77 (95% CI 0.61-0.93) in controls. Lobar analysis revealed reduced scaling in the parietal (0.50, 95% CI 0.42-0.59) and occipital (0.67, 95% CI 0.54-0.80) lobes of patients with FGFR compared with controls. Modified learning environments were needed more often in patients with FGFR. INTERPRETATION: Despite adequate ICV in FGFR-mediated craniosynostosis, CSA development is reduced, indicating maldevelopment, particularly in parietal and occipital lobes. Modified education is also more common in patients with FGFR.


Assuntos
Córtex Cerebral/anormalidades , Craniossinostoses/complicações , Malformações do Desenvolvimento Cortical/etiologia , Adolescente , Córtex Cerebral/diagnóstico por imagem , Criança , Pré-Escolar , Craniossinostoses/diagnóstico por imagem , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Adulto Jovem
6.
Stroke ; 52(3): 922-930, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33535785

RESUMO

BACKGROUND AND PURPOSE: Cortical cerebral microinfarcts (CMIs) have been linked with dementia and impaired cognition in cross-sectional studies. However, the clinical relevance of CMIs in a large population-based setting is lacking. We examine the association of cortical CMIs detected on 1.5T magnetic resonance imaging with cardiovascular risk factors, cerebrovascular disease, and brain tissue volumes. We further explore the association between cortical CMIs with cognitive decline and risk of stroke, dementia, and mortality in the general population. METHODS: Two thousand one hundred fifty-six participants (age: 75.7±5.9 years, women: 55.6%) with clinical history and baseline magnetic resonance imaging (January 2009-December 2013) were included from the Rotterdam Study. Cortical CMIs were graded based on a previously validated method. Markers of cerebrovascular disease and brain tissue volumes were assessed on magnetic resonance imaging. Cognition was assessed using a detailed neuropsychological test at baseline and at 5 years of follow-up. Data on incident stroke, dementia, and mortality were included until January 2016. RESULTS: Two hundred twenty-seven individuals (10.5%) had ≥1 cortical CMIs. The major risk factors of cortical CMIs were male sex, current smoking, history of heart disease, and stroke. Furthermore, presence of cortical CMIs was associated with infarcts and smaller brain volume. Persons with cortical CMIs showed cognitive decline in Stroop tests (color-naming and interference subtasks; ß for color-naming, 0.18 [95% CI, 0.04-0.33], P interaction ≤0.001 and ß for interference subtask, 1.74, [95% CI, 0.66-2.82], P interaction ≤0.001). During a mean follow-up of 5.2 years, 73 (4.3%) individuals developed incident stroke, 95 (5.1%) incident dementia, and 399 (19.2%) died. People with cortical CMIs were at an increased risk of stroke (hazard ratio, 1.18 [95% CI, 1.09-1.28]) and mortality (hazard ratio, 1.09 [95% CI, 1.00-1.19]). CONCLUSIONS: Cortical CMIs are highly prevalent in a population-based setting and are associated with cardiovascular disease, cognitive decline, and increased risk of stroke and mortality. Future investigations will have to show whether cortical CMIs are a useful biomarker to intervene upon to reduce the burden of stroke.


Assuntos
Infarto Encefálico/diagnóstico , Encéfalo/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Demência/diagnóstico , Imageamento por Ressonância Magnética/métodos , Idoso , Biomarcadores , Infarto Encefálico/epidemiologia , Cognição , Demência/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Modelos de Riscos Proporcionais , Fatores de Risco
7.
Neuroimage ; 227: 117646, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33338617

RESUMO

Alzheimer's disease (AD) is the most common form of dementia and is phenotypically heterogeneous. APOE is a triallelic gene which correlates with phenotypic heterogeneity in AD. In this work, we determined the effect of APOE alleles on the disease progression timeline of AD using a discriminative event-based model (DEBM). Since DEBM is a data-driven model, stratification into smaller disease subgroups would lead to more inaccurate models as compared to fitting the model on the entire dataset. Hence our secondary aim is to propose and evaluate novel approaches in which we split the different steps of DEBM into group-aspecific and group-specific parts, where the entire dataset is used to train the group-aspecific parts and only the data from a specific group is used to train the group-specific parts of the DEBM. We performed simulation experiments to benchmark the accuracy of the proposed approaches and to select the optimal approach. Subsequently, the chosen approach was applied to the baseline data of 417 cognitively normal, 235 mild cognitively impaired who convert to AD within 3 years, and 342 AD patients from the Alzheimers Disease Neuroimaging Initiative (ADNI) dataset to gain new insights into the effect of APOE carriership on the disease progression timeline of AD. In the ε4 carrier group, the model predicted with high confidence that CSF Amyloidß42 and the cognitive score of Alzheimer's Disease Assessment Scale (ADAS) are early biomarkers. Hippocampus was the earliest volumetric biomarker to become abnormal, closely followed by the CSF Phosphorylated Tau181 (PTAU) biomarker. In the homozygous ε3 carrier group, the model predicted a similar ordering among CSF biomarkers. However, the volume of the fusiform gyrus was identified as one of the earliest volumetric biomarker. While the findings in the ε4 carrier and the homozygous ε3 carrier groups fit the current understanding of progression of AD, the finding in the ε2 carrier group did not. The model predicted, with relatively low confidence, CSF Neurogranin as one of the earliest biomarkers along with cognitive score of Mini-Mental State Examination (MMSE). Amyloid ß42 was found to become abnormal after PTAU. The presented models could aid understanding of the disease, and in selecting homogeneous group of presymptomatic subjects at-risk of developing symptoms for clinical trials.


Assuntos
Algoritmos , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Apolipoproteínas E/genética , Idoso , Doença de Alzheimer/fisiopatologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Progressão da Doença , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Neuroimagem/métodos
8.
Am J Geriatr Psychiatry ; 29(2): 156-165, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32651052

RESUMO

OBJECTIVE: The impact of white matter hyperintensities (WMH) on language possibly depends on lesion location through disturbance of strategic white matter tracts. We examined the impact of WMH location on language in elderly Asians. DESIGN: Cross-sectional. SETTING: Population-based. PARTICIPANTS: Eight-hundred nineteen residents of Singapore, ages (≥65 years). MEASUREMENTS: Clinical, cognitive and 3T magnetic resonance imaging assessments were performed on all participants. Language was assessed using the Modified Boston Naming Test (MBNT) and Verbal Fluency (VF). Hypothesis-free region-of-interest-based (ROI) analyses based on major white matter tracts were used to determine the association between WMH location and language. Conditional dependencies between the regional WMH volumes and language were examined using Bayesian-network analysis. RESULTS: ROI-based analyses showed that WMH located within the anterior thalamic radiation (mean difference: -0.12, 95% confidence interval [CI]: -0.22; -0.02, p = 0.019) and uncinate fasciculus (mean difference: -0.09, 95% CI: -0.18; -0.01, p = 0.022) in the left hemisphere were significantly associated with worse VF but did not survive multiple testing. Conversely, WMH volume in the left cingulum of cingulate gyrus was significantly associated with MBNT performance (mean difference: -0.09, 95% CI: -0.17; -0.02, p = 0.016). Bayesian-network analyses confirmed the left cingulum of cingulate gyrus as a direct determinant of MBNT performance. CONCLUSION: Our findings identify the left cingulum of cingulate gyrus as a strategic white matter tract for MBNT, suggesting that language - is sensitive to subcortical ischemic damage. Future studies on the role of sporadic ischemic lesions and vascular cognitive impairment should not only focus on total WMH volume but should also take WMH lesion location into account when addressing language.


Assuntos
Idioma , Substância Branca/patologia , Idoso , Teorema de Bayes , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Singapura
9.
Eur J Pediatr ; 180(4): 1211-1217, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33151409

RESUMO

In this study, we diagnose skull shape deformities by analysing sinusoid curves obtained from standardized computed tomography (CT) slices of the skull for the common craniosynostoses (scaphocephaly, brachycephaly, trigonocephaly, right- and left-sided anterior plagiocephaly). Scaphocephaly has a high forehead peak and low troughs, in contrast to brachycephaly. Anterior plagiocephaly has asymmetry and shifting of the forehead peak. Trigonocephaly has a high and narrow frontal peak. Control patients have a symmetrical skull shape with low troughs and a high and broader frontal peak. Firstly, we included 5 children of every group of the common craniosynostoses and additionally 5 controls for extraction and calculation of characteristics. A diagnostic flowchart was developed. Secondly, we included a total of 51 craniosynostosis patients to validate the flowchart. All patients were correctly classified using the flowchart.Conclusion: Our study proposes and implements a new diagnostic approach of craniosynostosis. We describe a diagnostic flowchart based on specific characteristics for every type of craniosynostosis related to the specific skull deformities and control patients. All variables are expressed in number; therefore, we are able to use these variables in future research to quantify the different types of craniosynostosis. What is Known: • Premature fusion of one or more cranial sutures results in a specific cranial shape. • Clinical diagnosis is relatively simple; however, objective diagnosis based on distinctive values is difficult. What is New: • Using external landmarks and curve analysis, distinctive variables, and values for every type of craniosynostosis related to the specific skull deformities were determined and used to create a diagnostic flowchart for diagnosis. • Validation with an independent data set of 51 patients showed that all patients were correctly classified.


Assuntos
Craniossinostoses , Criança , Craniossinostoses/diagnóstico por imagem , Humanos , Lactente , Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X
10.
Alzheimers Dement ; 17(10): 1649-1662, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33792168

RESUMO

INTRODUCTION: There is increasing evidence that phosphorylated tau (P-tau181) is a specific biomarker for Alzheimer's disease (AD) pathology, but its potential utility in non-White patient cohorts and patients with concomitant cerebrovascular disease (CeVD) is unknown. METHODS: Single molecule array (Simoa) measurements of plasma P-tau181, total tau, amyloid beta (Aß)40 and Aß42, as well as derived ratios were correlated with neuroimaging modalities indicating brain amyloid (Aß+), hippocampal atrophy, and CeVD in a Singapore-based cohort of non-cognitively impaired (NCI; n = 43), cognitively impaired no dementia (CIND; n = 91), AD (n = 44), and vascular dementia (VaD; n = 22) subjects. RESULTS: P-tau181/Aß42 ratio showed the highest area under the curve (AUC) for Aß+ (AUC = 0.889) and for discriminating between AD Aß+ and VaD Aß- subjects (AUC = 0.903). In addition, P-tau181/Aß42 ratio was associated with hippocampal atrophy. None of the biomarkers was associated with CeVD. DISCUSSION: Plasma P-tau181/Aß42 ratio may be a noninvasive means of identifying AD with elevated brain amyloid in populations with concomitant CeVD.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/sangue , Povo Asiático/estatística & dados numéricos , Transtornos Cerebrovasculares/complicações , Fragmentos de Peptídeos/sangue , Proteínas tau/sangue , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/patologia , Atrofia/patologia , Biomarcadores/sangue , Encéfalo/patologia , Disfunção Cognitiva/patologia , Estudos de Coortes , Hipocampo/patologia , Humanos , Fosforilação , Tomografia por Emissão de Pósitrons , Singapura
11.
Cleft Palate Craniofac J ; 58(7): 832-837, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33078622

RESUMO

OBJECTIVES: Severity of unilateral coronal synostosis (UCS) can vary. Quantification is important for treatment, expectations of treatment and natural outcome, and education of the patient and parents. DESIGN: Retrospective study. SETTING: Primary craniofacial center. PATIENTS, PARTICIPANTS: Twenty-three preoperative patients with unilateral coronal craniosynostosis (age < 2 years). INTERVENTION: Utrecht Cranial Shape Quantifier (UCSQ) was used to quantify severity using the variables: asymmetry ratio of frontal peak and ratio of frontal peak gradient. MAIN OUTCOME MEASURES(S): The UCSQ variables were combined and related to visual score using Pearson correlation coefficient; UCSQ and visual score were additionally compared to Di Rocco classification by one-way analysis of variance or Kruskal-Wallis test. All measurements were made on computed tomography scans. RESULTS: Good correlation between UCSQ and visual score was found (r = 0.67). No statistically significant differences were found between group means of UCSQ in the 3 categories of Di Rocco classification (F2,20 = 0.047; P > .05). Kruskal-Wallis test showed no significant differences between group means of visual score in the 3 categories of Di Rocco classification (Kruskal-Wallis H (2) = 0.871; P > .05). CONCLUSIONS: Using UCSQ, we can quantify UCS according to severity using characteristics, it outperforms traditional methods and captures the whole skull shape. In future research, we can apply UCSQ to 3D-photogrammetry due to the utilization of external landmarks.


Assuntos
Craniossinostoses , Sinostose , Pré-Escolar , Suturas Cranianas , Craniossinostoses/diagnóstico por imagem , Humanos , Lactente , Fotogrametria , Estudos Retrospectivos , Crânio , Tomografia Computadorizada por Raios X
12.
Eur J Nucl Med Mol Imaging ; 47(2): 319-331, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31863136

RESUMO

PURPOSE: The analysis of the [11C]PiB-PET amyloid images of a unique Asian cohort of 186 participants featuring overlapping vascular diseases raised the question about the validity of current standards for amyloid quantification under abnormal conditions. In this work, we implemented a novel pipeline for improved amyloid PET quantification of this atypical cohort. METHODS: The investigated data correction and amyloid quantification methods included motion correction, standardized uptake value ratio (SUVr) quantification using the parcellated MRI (standard method) and SUVr quantification without MRI. We introduced a novel amyloid analysis method yielding 2 biomarkers: AßL which quantifies the global Aß burden and ns that characterizes the non-specific uptake. Cut-off points were first determined using visual assessment as ground truth and then using unsupervised classification techniques. RESULTS: Subject's motion impacts the accuracy of the measurement outcome but has however a limited effect on the visual rating and cut-off point determination. SUVr computation can be reliably performed for all the subjects without MRI parcellation while, when required, the parcellation failed or was of mediocre quality in 10% of the cases. The novel biomarker AßL showed an association increase of 29.5% with the cognitive tests and increased effect size between positive and negative scans compared with SUVr. ns was found sensitive to cerebral microbleeds, white matter hyperintensity, volume, and age. The cut-off points for SUVr using parcellated MRI, SUVr without parcellation, and AßL were 1.56, 1.39, and 25.5. Finally, k-means produced valid cut-off points without the requirement of visual assessment. CONCLUSION: The optimal processing for the amyloid quantification of this atypical cohort allows the quantification of all the subjects, producing SUVr values and two novel biomarkers: AßL, showing important increased in their association with various cognitive tests, and ns, a parameter sensitive to non-specific retention variations caused by age and cerebrovascular diseases.


Assuntos
Doença de Alzheimer , Transtornos Cerebrovasculares , Amiloide , Peptídeos beta-Amiloides , Compostos de Anilina , Biomarcadores , Transtornos Cerebrovasculares/diagnóstico por imagem , Humanos , Tomografia por Emissão de Pósitrons
13.
Dev Med Child Neurol ; 62(7): 799-805, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32060907

RESUMO

AIM: To evaluate the impact of risk factors for intracranial hypertension (ICH) on cerebral cortex thickness in syndromic craniosynostosis. METHOD: ICH risk factors including papilloedema, hydrocephalus, obstructive sleep apnea (OSA), cerebellar tonsillar position, occipitofrontal circumference (OFC) curve deflection, age, and sex were collected from the records of patients with syndromic craniosynostosis (Apert, Crouzon, Pfeiffer, Muenke, Saethre-Chotzen syndromes) and imaging. Magnetic resonance images were analysed and exported for statistical analysis. A linear mixed model was developed to determine correlations with cerebral cortex thickness changes. RESULTS: In total, 171 scans from 107 patients (83 males, 88 females [including repeated scans], mean age 8y 10mo, range 1y 1mo-34y, SD 5y 9mo) were evaluated. Mean cortical thickness in this cohort was 2.78mm (SD 0.17). Previous findings of papilloedema (p=0.036) and of hydrocephalus (p=0.007) were independently associated with cortical thinning. Cortical thickness did not vary significantly by sex (p=0.534), syndrome (p=0.896), OSA (p=0.464), OFC (p=0.375), or tonsillar position (p=0.682). INTERPRETATION: Detection of papilloedema or hydrocephalus in syndromic craniosynostosis is associated with significant changes in cortical thickness, supporting the need for preventative rather than reactive treatment strategies. WHAT THIS PAPER ADDS: Papilloedema is associated with thinning of the cerebral cortex in syndromic craniosynostosis, independently of hydrocephalus.


Hipertensión intracraneal y grosor cortical en craneosinostosis sindrómica OBJETIVO: Evaluar el impacto de los factores de riesgo de hipertensión intracraneal (HIC) en el grosor de la corteza cerebral en la craneosinostosis sindrómica. MÉTODO: La neuroimagen, y, los factores de riesgo para HIC que incluyeron papiledema, hidrocefalia, apnea obstructiva del sueño (SAOS), posición de la tonsila cerebelosa, edad de desviación de la curva de circunferencia occipitofrontal (CFO) y el sexo, se recogieron de los registros de pacientes con craneosinostosis sindrómica (Apert, Crouzon, Pfeiffer, Muenke, Saethre-Chotzensis). Las imágenes de resonancia magnética fueron analizadas y exportadas para análisis estadístico. Se desarrolló un modelo mixto lineal para determinar las correlaciones con los cambios en el espesor de la corteza cerebral. RESULTADOS: En total se evaluaron 171 exploraciones de 107 pacientes (83 varones, 88 mujeres [incluyendo escaneos repetidos], edad media 8 años 10 meses, rango 1 año 1 mes - 34 años, DE 5 años 9 meses). El espesor medio cortical en esta cohorte fue de 2,78 mm (DS 0,17). Los hallazgos anteriores de papiledema (p=0,036) y de hidrocefalia (p=0,007) se asociaron de forma independiente con el adelgazamiento cortical. El grosor cortical no varió significativamente por sexo (p=0,534), síndrome (p=0,896), SAOS (p=0,464), CFO (p=0,375), o posición tonsilar (p=0,682). INTERPRETACIÓN: La detección de papiledema o hidrocefalia en la craneosinostosis sindrómica, se asocia con cambios significativos en el grosor cortical. Esto apoya la necesidad de estrategias de tratamiento preventivo en lugar de tratamientos reactivos.


Hipertensão intracrianiana e espessura cortical na craniossinostose sindrômica OBJETIVO: Avaliar o impacto de fatores de risco para hipertensão intracraniana (HIC) na espessura cortical em craniossinostose sindrômica. MÉTODO: Fatores de risco para HIC incluindo papiloedema, hidrocefalia, apnéia obstrutiva do sono (AOS), posição das tonsilas do cerebelo, idade de deflexão da curva da circunferência occipitofrontal (COF), e sexo foram coletados dos registros de pacientes com craniossinostose sindrômica (síndromes de Apert, Crouzon, Pfeiffer, Muenke, Saethre-Chotzen) e imagens. As imagens de ressonância magnética foram analisadas e exportadas para análise estatística. Um modelo linear misto foi desenvolvido para determinar correlações com mudanças na espessura do córtex cerebral. RESULTADOS: No total, 171 imagens de 107 pacientes (83 do sexo masculino, 88 do sexo feminino [incluindo varreduras repetidas], média de idade 8a 10m, variação 1a 1m-34a, DP 5a 9m) foram avaliados. A espessura cortical média nesta coorte foi 2,78mm (DP 0,17). Achados prévios de papiloedema (p=0,036) e de hidrocefalia (p=0,007) foram independentemente associados com a redução cortical. A espessura cortical não variou significativamente com o sexo (p=0,534), síndrome (p=0,896), AOS (p=0,464), COF (p=0,375), ou posição tonsilar (p=0,682). INTERPRETAÇÃO: A detecção do papiloedema ou hidrocefalia na craniossinostose sindrômica se associa com mudanças significativas na espessura cortical, sustentando a necessidade de estratégias de tratamento preventivas e não reativas.


Assuntos
Córtex Cerebral/patologia , Craniossinostoses/diagnóstico , Hidrocefalia/diagnóstico , Hipertensão Intracraniana/diagnóstico , Papiledema/diagnóstico , Adolescente , Adulto , Córtex Cerebral/diagnóstico por imagem , Criança , Pré-Escolar , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/patologia , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/patologia , Lactente , Hipertensão Intracraniana/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Papiledema/diagnóstico por imagem , Papiledema/patologia , Fatores de Risco , Síndrome , Adulto Jovem
14.
Eur J Pediatr ; 179(10): 1569-1577, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32303825

RESUMO

We present a novel technique for classification of skull deformities due to most common craniosynostosis. We included 5 children of every group of the common craniosynostoses (scaphocephaly, brachycephaly, trigonocephaly, and right- and left-sided anterior plagiocephaly) and additionally 5 controls. Our outline-based classification method is described, using the software programs OsiriX, MeVisLab, and Matlab. These programs were used to identify chosen landmarks (porion and exocanthion), create a base plane and a plane at 4 cm, segment outlines, and plot resulting graphs. We measured repeatability and reproducibility, and mean curves of groups were analyzed. All raters achieved excellent intraclass correlation scores (0.994-1.000) and interclass correlation scores (0.989-1.000) for identifying the external landmarks. Controls, scaphocephaly, trigonocephaly, and brachycephaly all have the peak of the forehead in the middle of the curve (180°). In contrary, in anterior plagiocephaly, the peak is shifted (to the left of graph in right-sided and vice versa). Additionally, controls, scaphocephaly, and trigonocephaly have a high peak of the forehead; scaphocephaly has the lowest troughs; in brachycephaly, the width/frontal peak ratio has the highest value with a low frontal peak.Conclusion: We introduced a preliminary study showing an objective and reproducible methodology using CT scans for the analysis of craniosynostosis and potential application of our method to 3D photogrammetry. What is Known: • Diagnosis of craniosynostosis is relatively simple; however, classification of craniosynostosis is difficult and current techniques are not widely applicable. What is New: • We introduce a novel technique for classification of skull deformities due to craniosynostosis, an objective and reproducible methodology using CT scans resulting in characteristic curves. The method is applicable to all 3D-surface rendering techniques. • Using external landmarks and curve analysis, specific and characteristic curves for every type of craniosynostosis related to the specific skull deformities are found.


Assuntos
Craniossinostoses , Criança , Craniossinostoses/diagnóstico por imagem , Humanos , Lactente , Reprodutibilidade dos Testes , Projetos de Pesquisa , Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X
15.
Neuroimage ; 189: 432-444, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30659958

RESUMO

Structural brain markers are studied extensively in the field of neurodegeneration, but are thought to occur rather late in the process. Functional measures such as functional connectivity are gaining interest as potentially more subtle markers of neurodegeneration. However, brain structure and function are also affected by 'normal' brain ageing. More information is needed on how functional connectivity relates to aging, particularly in the absence of overt neurodegenerative disease. We investigated the association of age with resting-state functional connectivity in 2878 non-demented persons between 50 and 95 years of age (54.1% women) from the population-based Rotterdam Study. We obtained nine well-known resting state networks using data-driven methodology. Within the anterior default mode network, ventral attention network, and sensorimotor network, functional connectivity was significantly lower with older age. In contrast, functional connectivity was higher with older age within the visual network. Between resting state networks, we found patterns of both increases and decreases in connectivity in approximate equal proportions. Our results reinforce the notion that the aging brain undergoes a reorganization process, and serves as a solid basis for exploring functional connectivity as a preclinical marker of neurodegenerative disease.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Conectoma/métodos , Rede Nervosa/fisiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Países Baixos
16.
Eur Radiol ; 27(9): 3716-3724, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28289940

RESUMO

OBJECTIVES: Diminished function of the posterior cingulate cortex (PCC) is a typical finding in early Alzheimer's disease (AD). It is hypothesized that in early stage AD, PCC functioning relates to or reflects hippocampal dysfunction or atrophy. The aim of this study was to examine the relationship between hippocampus function, volume and structural connectivity, and PCC activation during an episodic memory task-related fMRI study in mild cognitive impairment (MCI). METHOD: MCI patients (n = 27) underwent episodic memory task-related fMRI, 3D-T1w MRI, 2D T2-FLAIR MRI and diffusion tensor imaging. Stepwise linear regression analysis was performed to examine the relationship between PCC activation and hippocampal activation, hippocampal volume and diffusion measures within the cingulum along the hippocampus. RESULTS: We found a significant relationship between PCC and hippocampus activation during successful episodic memory encoding and correct recognition in MCI patients. We found no relationship between the PCC and structural hippocampal predictors. CONCLUSIONS: Our results indicate a relationship between PCC and hippocampus activation during episodic memory engagement in MCI. This may suggest that during episodic memory, functional network deterioration is the most important predictor of PCC functioning in MCI. KEY POINTS: • PCC functioning during episodic memory relates to hippocampal functioning in MCI. • PCC functioning during episodic memory does not relate to hippocampal structure in MCI. • Functional network changes are an important predictor of PCC functioning in MCI.


Assuntos
Disfunção Cognitiva/fisiopatologia , Giro do Cíngulo/fisiopatologia , Hipocampo/patologia , Hipocampo/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Memória Episódica , Rede Nervosa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Atrofia/patologia , Estudos de Casos e Controles , Disfunção Cognitiva/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Análise de Regressão , Lobo Temporal/fisiopatologia
17.
Alzheimer Dis Assoc Disord ; 29(1): 12-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24731981

RESUMO

Extracranial carotid artery disease has been shown to be related to cognitive deficits. However, limited data are available on intracranial stenosis (ICS) and cognitive impairment. We investigate the association between ICS and cognitive impairment in Chinese. Subjects (n=278), recruited from the Epidemiology of Dementia in Singapore Study, underwent comprehensive clinical evaluation, neuropsychological testing, and brain magnetic resonance imaging (MRI), including 3-dimensional-time-of-flight magnetic resonance angiography (MRA). Cognitive function was expressed as composite and domain-specific Z-scores. Cognitive impairment no dementia and dementia were diagnosed according to internationally accepted diagnostic criteria. Linear and logistic regression models were adjusted for age, sex, education, vascular risk factors, and other MRI markers. A total of 29 (10.4%) persons had ICS on MRA, which was significantly associated with both composite cognitive Z-scores [mean difference in Z-score, presence vs. absence of ICS: -0.37 (95% confidence interval: -0.63, -0.12)] and specific domains including executive function, language, visuomotor speed, verbal memory, and visual memory. ICS was also related to significant cognitive impairment (odds ratio: 5.10 [1.24 to 21.02]). With respect to other MRI markers, adjusted for the presence of lacunar infarcts, the associations of ICS with both composite and domain-specific Z-scores, and significant cognitive impairment became nonsignificant; however, adjustment for other MRI markers did not alter these associations. In this Chinese population, presence of ICS was associated with cognitive impairment independent of vascular risk factors. These associations may be mediated through the presence of infarcts.


Assuntos
Povo Asiático/etnologia , Doenças Arteriais Cerebrais/diagnóstico , Doenças Arteriais Cerebrais/etnologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etnologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Arteriais Cerebrais/psicologia , Transtornos Cognitivos/psicologia , Constrição Patológica/diagnóstico , Constrição Patológica/etnologia , Constrição Patológica/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
18.
Neuroepidemiology ; 42(2): 131-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24481144

RESUMO

BACKGROUND: Previous studies have assessed the association between ankle-brachial index (ABI) and cognition, mainly using brief cognitive tests. We investigated whether ABI was associated with cognition independent of neuroimaging markers of cerebrovascular disease. METHODS: Chinese subjects (n = 278, aged ≥60 years) were recruited from the ongoing Epidemiology of Dementia in Singapore (EDIS) Study. Ankle and brachial blood pressures were measured, and low ABI was defined as ≤0.9. A neuropsychological battery was utilized to determine cognition. Cognitive impairment no dementia (CIND) and dementia were diagnosed according to standard diagnostic criteria. Magnetic resonance imaging (MRI) was used to obtain semiquantitative and quantitative markers of cerebrovascular disease and atrophy. RESULTS: A low ABI was related to the presence of intracranial stenosis (odds ratio, OR = 1.71; 95% confidence interval, CI: 1.13-2.59), but not with the presence of infarcts, microbleeds or grey matter, white matter and white matter lesion volumes. Furthermore, a low ABI was associated with poorer overall cognitive function and CIND-moderate/dementia (OR = 2.26; 95% CI: 1.11-4.59), independent of cardiovascular risk factors, and the MRI markers related to cerebrovascular disease and atrophy. CONCLUSION: We found an association between a low ABI and cognitive impairment, independent of any MRI marker of cerebral small vessel disease or large artery atherosclerotic disease.


Assuntos
Índice Tornozelo-Braço , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cognitivos/diagnóstico , Idoso , China , Constrição Patológica , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos
19.
Alzheimer Dis Assoc Disord ; 28(2): 106-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24322485

RESUMO

Cerebral microbleeds (CMBs) are considered to be a novel marker of cerebral small vessel disease. However, the link with cognitive impairment remains unclear. We investigated whether CMBs-independent of other traditional markers of cerebral small vessel disease-are related to cognition. Chinese subjects from the population-based Singapore Chinese Eye Study, who failed an initial cognitive screening and were recruited into the ongoing Epidemiology of Dementia in Singapore Study, underwent neuropsychological testing and 3 T brain magnetic resonance imaging. The presence and number of CMBs were graded using Brain Observer Microbleed Scale on susceptibility-weighted images. Other magnetic resonance imaging lesions that were graded included presence of lacunes, white matter lesion, and total brain volumes. A comprehensive neuropsychological battery was administered and cognitive function was summarized as composite and domain-specific Z-scores. Among 282 subjects, 91 had any CMBs (32.3%), of whom 36 (12.8%) had multiple CMBs. CMBs were-independent of cardiovascular risk factors and other markers of cerebral small vessel disease-significantly associated with poorer cognitive function as reflected by composite Z-score (mean difference per CMB increase: -0.06; 95% confidence interval: -0.11, -0.01] and with domain-specific Z-scores including executive function, attention, and visuoconstruction. Among Chinese subjects CMBs were, independent of other concomitant markers of cerebral small vessel disease, associated with poorer cognitive function.


Assuntos
Hemorragia Cerebral/epidemiologia , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Transtornos Cognitivos/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Atenção/fisiologia , Encéfalo/patologia , Hemorragia Cerebral/patologia , Doenças de Pequenos Vasos Cerebrais/patologia , Transtornos Cognitivos/fisiopatologia , Função Executiva/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de Risco , Singapura/epidemiologia
20.
Alzheimers Dement (Amst) ; 16(2): e12576, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605996

RESUMO

INTRODUCTION: While elevated blood glial fibrillary acidic protein (GFAP) has been associated with brain amyloid pathology, whether this association occurs in populations with high cerebral small vessel disease (CSVD) concomitance remains unclear. METHODS: Using a Singapore-based cohort of cognitively impaired subjects, we assessed associations between plasma GFAP and neuroimaging measures of brain amyloid and CSVD, including white matter hyperintensities (WMH). We also examined the diagnostic performance of plasma GFAP in detecting brain amyloid beta positivity (Aß+). RESULTS: When stratified by WMH status, elevated brain amyloid was associated with higher plasma GFAP only in the WMH- group (ß = 0.383; P < 0.001). The diagnostic performance of plasma GFAP in identifying Aß+ was significantly higher in the WMH- group (area under the curve [AUC] = 0.896) than in the WMH+ group (AUC = 0.712, P = 0.008). DISCUSSION: The biomarker utility of plasma GFAP in detecting brain amyloid pathology is dependent on the severity of concomitant WMH. Highlight: Glial fibrillary acidic protein (GFAP)'s association with brain amyloid is unclear in populations with high cerebral small vessel disease (CSVD).Plasma GFAP was measured in a cohort with CSVD and brain amyloid.Plasma GFAP was better in detecting amyloid in patients with low CSVD versus high CSVD.Biomarker utility of GFAP in detecting brain amyloid depends on the severity of CSVD.

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