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1.
Eur J Neurosci ; 55(5): 1373-1387, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35083790

RESUMEN

The aim of the present study was to investigate whether grey matter (GM) reductions in acute anorexia nervosa (AN) are (i) valid for adolescents (age 14-18 years), (ii) reversible following short-term psychotherapeutic and nutritional therapy and (iii) depend on psychological components like attachment trauma. 3T MRI including a high-resolution T1 MPRAGE was performed in 22 female adolescents in the acute state of AN (age: 15.2 ± 1.2 years) and after weight restoration (duration: 2.6 ± 1 months, n = 18) and compared with 18 gender-matched healthy controls. The Adult Attachment Projective Picture System was used to classify resolved and unresolved attachment patterns. GM decreases were localized in extensive cortical areas including the insula, prefrontal and cingulate cortices as well as subcortical regions during acute AN, which partially increased after therapy with a relative sparing of the hippocampus and parahippocampal gyrus. The resolved group showed more GM recovery in regions of the left hippocampus and parahippocampal gyrus, bilateral cerebellar regions, right precuneus and adjacent cingulate cortices relative to the unresolved pattern. Structural anomalies in adolescent AN that recovered after treatment may be primarily the consequence of malnutrition, whereas several regions did not display significant recovery. Attachment status seems to influence region-specific GM recovery.


Asunto(s)
Anorexia Nerviosa , Sustancia Gris , Adolescente , Adulto , Anorexia Nerviosa/diagnóstico por imagen , Anorexia Nerviosa/terapia , Encéfalo , Femenino , Sustancia Gris/diagnóstico por imagen , Giro del Cíngulo , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética
2.
J Neuroradiol ; 49(5): 370-379, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34871672

RESUMEN

BACKGROUND AND PURPOSE: Phosphorous magnetic resonance spectroscopy (31P-MRS) allows a non-invasive analysis of phosphorus-containing compounds in vivo. The present study investigated the influence of brain region, hemisphere, age, sex and brain volume on 31P-MRS metabolites in healthy adults. MATERIALS AND METHODS: Supratentorial brain 31P-MRS spectra of 125 prospectively recruited healthy volunteers (64 female, 61 male) aged 20 to 85 years (mean: 49.4 ± 16.9 years) were examined with a 3D-31P-MRS sequence at 3T, and the compounds phosphocreatine (PCr), inorganic phosphate (Pi) and adenosine triphosphate (ATP) were measured. From this data, the metabolite ratios PCr/ATP, Pi/ATP and PCr/Pi were calculated for different brain regions. In addition, volumes of gray matter, white matter and cerebrospinal fluid were determined. RESULTS: For all metabolite ratios significant regional differences and in several regions sex differences were found. In some brain regions and for some metabolites hemispheric differences were detected. In addition, changes with aging were found, which differed between women and men. CONCLUSIONS: The present results indicate that 31P-MRS metabolism varies throughout the brain, with age and between sexes, and therefore have important practical implications for the design and the interpretation of future 31P-MRS studies under physiological conditions and in patients with various cerebral diseases.


Asunto(s)
Encéfalo , Metabolismo Energético , Adenosina Trifosfato , Adulto , Femenino , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Fosfocreatina
3.
Gerontology ; 66(6): 582-592, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32980844

RESUMEN

INTRODUCTION: Previous studies have shown an association between a high health numeracy and good cognitive functioning. OBJECTIVE: To investigate the moderation effect of education on this relationship and which brain structures support health numeracy. METHODS: We examined 70 healthy older persons (66% females; mean ± SD: age, 75.73 ± 4.52 years; education, 12.21 ± 2.94 years). The participants underwent a T1-weighted 3-T MRI and a neuropsychological assessment including a health numeracy task. Statistical parametric mapping was applied to identify focal changes in cortical thickness throughout the entire brain and to correlate image parameters with behavioral measures. RESULTS: Executive functions and mental calculation emerged as predictors of health numeracy (B = 0.22, p < 0.05, and B = 0.38, p < 0.01). An interaction was found between education and executive functions (B = -0.16, p = 0.01) and between education and mental calculation (B = -0.11, p < 0.05). Executive functions and mental calculation had an impact on health numeracy in participants with a low to intermediate edu-cation (≤12 years) but not in those with a higher education (>12 years). Health numeracy scores were associated with cortical thickness in the right dorsomedial prefrontal cortex and the right superior temporal gyrus (p = 0.01). CONCLUSIONS: Older people with a higher education perform better in health numeracy tasks than those with a lower education. They have access to previously acquired knowledge about ratio concepts and do not need to rely on executive functions and computational skills. This is highly relevant when decisions about health care have to be made.


Asunto(s)
Envejecimiento/psicología , Cognición , Escolaridad , Función Ejecutiva , Matemática , Anciano , Anciano de 80 o más Años , Toma de Decisiones , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas/estadística & datos numéricos
4.
Eur Radiol ; 28(11): 4534-4541, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29728814

RESUMEN

OBJECTIVE: The aim was to investigate whether dual-energy computed tomography (DECT) reconstructions optimised for oedema visualisation (oedema map; EM) facilitate an improved detection of early infarctions after endovascular stroke therapy (EST). METHODS: Forty-six patients (21 women; 25 men; mean age: 63 years; range 24-89 years) were included. The brain window (BW), virtual non-contrast (VNC) and modified VNC series based on a three-material decomposition technique optimised for oedema visualisation (EM) were evaluated. Follow-up imaging was used as the standard for comparison. Contralateral side to infarction differences in density (CIDs) were determined. Infarction detectability was assessed by two blinded readers, as well as image noise and contrast using Likert scales. ROC analyses were performed and the respective Youden indices calculated for cut-off analysis. RESULTS: The highest CIDs were found in the EM series (73.3 ± 49.3 HU), compared with the BW (-1.72 ± 13.29 HU) and the VNC (8.30 ± 4.74 HU) series. The EM was found to have the highest infarction detection rates (area under the curve: 0.97 vs. 0.54 and 0.90, p < 0.01) with a cut-off value of < 50.7 HU, despite slightly more pronounced image noise. The location of the infarction did not affect detectability (p > 0.05 each). CONCLUSIONS: The EM series allows higher contrast and better early infarction detection than the VNC or BW series after EST. KEY POINTS: • Dual-energy CT EM allows better early infarction detection than standard brain window. • Dual-energy CT EM series allow better early infarction detection than VNC series. • Dual-energy CT EM are modified VNC based on water content of tissue.


Asunto(s)
Edema Encefálico/diagnóstico , Encéfalo/patología , Infarto Cerebral/diagnóstico , Diagnóstico Precoz , Procedimientos Endovasculares/métodos , Imagenología Tridimensional , Tomografía Computarizada Multidetector/métodos , Adulto , Anciano , Anciano de 80 o más Años , Edema Encefálico/etiología , Infarto Cerebral/complicaciones , Infarto Cerebral/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
5.
Eur Radiol ; 27(3): 907-917, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27255400

RESUMEN

OBJECTIVES: After intraarterial recanalisation (IAR), the haemorrhage and the blood-brain barrier (BBB) disruption can be distinguished using dual-energy computed tomography (DECT). The aim of the present study was to investigate whether future infarction development can be predicted from DECT. METHODS: DECT scans of 20 patients showing 45 BBB disrupted areas after IAR were assessed and compared with follow-up examinations. Receiver operator characteristic (ROC) analyses using densities from the iodine map (IM) and virtual non-contrast (VNC) were performed. RESULTS: Future infarction areas are denser than future non-infarction areas on IM series (23.44 ± 24.86 vs. 5.77 ± 2.77; p < 0.0001) and more hypodense on VNC series (29.71 ± 3.33 vs. 35.33 ± 3.50; p < 0.0001). ROC analyses for the IM series showed an area under the curve (AUC) of 0.99 (cut-off: <9.97 HU; p < 0.05; sensitivity 91.18 %; specificity 100.00 %; accuracy 0.93) for the prediction of future infarctions. The AUC for the prediction of haemorrhagic infarctions was 0.78 (cut-off >17.13 HU; p < 0.05; sensitivity 90.00 %; specificity 62.86 %; accuracy 0.69). The VNC series allowed prediction of infarction volume. CONCLUSIONS: Future infarction development after IAR can be reliably predicted with the IM series. The prediction of haemorrhages and of infarction size is less reliable. KEY POINTS: • The IM series (DECT) can predict future infarction development after IAR. • Later haemorrhages can be predicted using the IM and the BW series. • The volume of definable hypodense areas in VNC correlates with infarction volume.


Asunto(s)
Barrera Hematoencefálica/diagnóstico por imagen , Hemorragia Cerebral/diagnóstico por imagen , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/cirugía , Procedimientos Endovasculares , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Barrera Hematoencefálica/fisiopatología , Hemorragia Cerebral/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
6.
BMC Med Imaging ; 16: 17, 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26911278

RESUMEN

BACKGROUND: Spondylosis leads to an overestimation of bone mineral density (BMD) with dual-energy x-ray absorptiometry (DXA) but not with quantitative computed tomography (QCT). The correlation between degenerative changes of the spine and QCT-BMD was therefore investigated for the first time. METHODS: One hundred thirty-four patients (66 female and 68 male) with a mean age of 49.0 ± 14.6 years (range: 19-88 years) who received a CT scan and QCT-BMD measurements of spine and hip were evaluated retrospectively. The occurrence and severity of spondylosis, osteochondrosis, and spondylarthrosis and the height of the vertebral bodies were assessed. RESULTS: A negative correlation was found between spinal BMD and number of spondylophytes (ρ = -0.35; p < 0.01), disc heights (r = -0.33; p < 0.01), number of discal air inclusions (ρ = -0.34; p < 0.01), the number of Schmorl nodules (ρ = -0.25; p < 0.01), the number (ρ = -0.219; p < 0.05) and the degree (ρ = -0.220; p < 0.05) of spondylarthrosis. Spinal and hip BMD correlated moderately, but the latter did not correlate with degenerative changes of the spine. In linear regression models age, osteochondrosis and spondylarthrosis were factors influencing spinal BMD. CONCLUSION: Degenerative spinal changes may be associated with reduced regional spinal mineralization. This knowledge could lead to a modification of treatment of degenerative spine disease with early treatment of osteopenia to prevent secondary fractures.


Asunto(s)
Cadera/diagnóstico por imagen , Enfermedades Neurodegenerativas/diagnóstico por imagen , Columna Vertebral/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Neurodegenerativas/patología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
7.
Neonatology ; 121(2): 213-221, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38052194

RESUMEN

INTRODUCTION: Preterm infants are at risk for impairment in brain maturation at term equivalent age (TEA). Diffusion tensor imaging (DTI) is a powerful magnetic resonance imaging (MRI) technique, quantitatively reflecting microstructural brain development of white matter regions with parameters such as fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Amplitude-integrated electroencephalography (aEEG) assesses electrocortical activity and brain function. METHODS: Aim of this study was to investigate a possible correlation between functional and microstructural brain maturation using neonatal aEEG and DTI-MRI at TEA. The study was conducted as a retrospective single-center study in 446 infants born below 32 gestational weeks. Spearman rank's correlation coefficients were calculated between aEEG (total maturation score) and FA/ADC value. To compare aEEG and DTI-MRI to neurodevelopmental outcome at 24 months of corrected age, we performed a multivariate linear regression analysis. RESULTS: Analysis showed an all-time significant correlation between total maturation score and FA/ADC values of the corpus callosum at TEA with the strongest correlation at day 2, day 3, week 3, and week 4. After including perinatal variables in the model, this correlation remained highly significant at day 2 and 3. When comparing the association of aEEG and DTI-MRI to outcome, both the total maturation score at day 2, day 3, and FA/ADC of the splenium of the corpus callosum showed a significant correlation. CONCLUSION: This study indicates that early monitoring of functional brain maturation may predict later assessment of microstructural brain development of corpus callosum in preterm infants with a relation to neurodevelopmental outcome.


Asunto(s)
Recien Nacido Prematuro , Sustancia Blanca , Lactante , Humanos , Recién Nacido , Imagen de Difusión Tensora/métodos , Estudios Retrospectivos , Imagen por Resonancia Magnética , Sustancia Blanca/diagnóstico por imagen , Encéfalo/diagnóstico por imagen
8.
Diagnostics (Basel) ; 14(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38667486

RESUMEN

One of the main causes of the dismal prognosis in patients who survive the initial bleeding after aneurysmal subarachnoidal hemorrhage is the delayed cerebral ischaemia caused by vasospasm. Studies suggest that cerebral magnesium and pH may potentially play a role in the pathophysiology of this adverse event. Using phosphorous magnetic resonance spectrocopy (31P-MRS), we calculated the cerebral magnesium (Mg) and pH levels in 13 patients who suffered from aSAH. The values between the group that developed clinically significant vasospasm (n = 7) and the group that did not (n = 6) were compared. The results of this study show significantly lower cerebral Mg levels (p = 0.019) and higher pH levels (p < 0.001) in the cumulative group (all brain voxels together) in patients who developed clinically significant vasospasm. Further clinical studies on a larger group of carefully selected patients are needed in order to predict clinically significant vasospasm.

9.
Diagnostics (Basel) ; 14(14)2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39061670

RESUMEN

INTRODUCTION: Aneurysmal wall enhancement (AWE) of non-ruptured sacular intracranial aneurysms (IA) after endovascular treatment (ET) is a frequently observed imaging finding using AWE-sequences in brain magnetic resonance imaging (MRI). So far, its value remains unclear. We aimed to investigate the effect of AWE on aneurysm reperfusion rates in a longitudinal cohort. METHODS: This is a retrospective MRI study over the timespan of up to 5 years, assessing the correlation of increased AWE of non-ruptured IAs and events of aneurysm reperfusion and retreatment, PHASES Score and grade of AWE. T1 SPACE fat saturation (FS) and T1 SE FS blood suppression sequences after contrast administration were used for visual interpretation of increased AWE. The IAs' sizes were assessed via the biggest diameter. The grade of enhancement was defined in a grading system from grade 1 to grade 3. RESULTS: 127 consecutive non ruptured IA-patients (58.9 ± 9.0 years, 94 female, 33 male) who underwent elective aneurysm occlusion were included. AWE was observed in 40.2% of patients (51/127) after ET, 6 patients already showed AWE before treatment. In large IAs (which were defined as a single maximum diameter of over 7.5 mm), AWE was significantly associated with aneurysm reperfusion in contrast to large aneurysm without AWE). All grades of AWE were significantly associated with reperfusion. CONCLUSIONS: Our data suggests that in patients with initially large IAs, AWE is correlated with aneurysm reperfusion.

10.
J Am Heart Assoc ; 13(9): e031816, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38639365

RESUMEN

BACKGROUND: Data on impact of COVID-19 vaccination and outcomes of patients with COVID-19 and acute ischemic stroke undergoing mechanical thrombectomy are scarce. Addressing this subject, we report our multicenter experience. METHODS AND RESULTS: This was a retrospective analysis of patients with COVID-19 and known vaccination status treated with mechanical thrombectomy for acute ischemic stroke at 20 tertiary care centers between January 2020 and January 2023. Baseline demographics, angiographic outcome, and clinical outcome evaluated by the modified Rankin Scale score at discharge were noted. A multivariate analysis was conducted to test whether these variables were associated with an unfavorable outcome, defined as modified Rankin Scale score >3. A total of 137 patients with acute ischemic stroke (48 vaccinated and 89 unvaccinated) with acute or subsided COVID-19 infection who underwent mechanical thrombectomy attributable to vessel occlusion were included in the study. Angiographic outcomes between vaccinated and unvaccinated patients were similar (modified Thrombolysis in Cerebral Infarction ≥2b: 85.4% in vaccinated patients versus 86.5% in unvaccinated patients; P=0.859). The rate of functional independence (modified Rankin Scale score, ≤2) was 23.3% in the vaccinated group and 20.9% in the unvaccinated group (P=0.763). The mortality rate was 30% in both groups. In the multivariable analysis, vaccination status was not a significant predictor for an unfavorable outcome (P=0.957). However, acute COVID-19 infection remained significant (odds ratio, 1.197 [95% CI, 1.007-1.417]; P=0.041). CONCLUSIONS: Our study demonstrated no impact of COVID-19 vaccination on angiographic or clinical outcome of COVID-19-positive patients with acute ischemic stroke undergoing mechanical thrombectomy, whereas worsening attributable to COVID-19 was confirmed.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Accidente Cerebrovascular Isquémico , Trombectomía , Vacunación , Humanos , COVID-19/complicaciones , COVID-19/terapia , COVID-19/mortalidad , Masculino , Femenino , Accidente Cerebrovascular Isquémico/mortalidad , Accidente Cerebrovascular Isquémico/cirugía , Estudios Retrospectivos , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Vacunas contra la COVID-19/efectos adversos , SARS-CoV-2 , Anciano de 80 o más Años
11.
Neonatology ; 120(6): 727-735, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37634498

RESUMEN

INTRODUCTION: There are some data indicating a negative impact of postnatal cytomegalovirus (CMV) infection on long-term neurodevelopmental outcome of preterm infants. So far, there is only little knowledge about a cerebral imaging correlate of these neurodevelopmental alterations induced by postnatal CMV infection in preterm infants. The aim of the current study was to investigate the effect of postnatal CMV infection on the incidence of brain injury and on microstructural brain maturation in very preterm infants at term-equivalent age. METHODS: Infants <32 gestational weeks (02/2011-11/2018) received cerebral MRI including axial diffusion-weighted images at term-equivalent age. All infants were screened for CMV infection using urine/saliva samples, and infection was regarded as acquired postnatal if a sample became positive >5 postnatal days. We compared brain injury as well as fractional anisotropy and apparent diffusion coefficient in 14 defined cerebral regions between infants with and without postnatal CMV infection. RESULTS: 401 infants were eligible, of whom 18 (4.5%) infants had a postnatal CMV infection. There were no significant differences in rates of brain injury or in microstructural brain development between both groups. This applied equally to the subgroup of infants <28 gestational weeks. CONCLUSION: Although infants with postnatal CMV infection were born more immature and more frequently suffered from complications related to immaturity, we neither observed a higher rate of preterm brain injury nor disadvantageous alterations in microstructural brain maturation at term-equivalent age.


Asunto(s)
Lesiones Encefálicas , Infecciones por Citomegalovirus , Enfermedades del Prematuro , Lactante , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Citomegalovirus , Infecciones por Citomegalovirus/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Retardo del Crecimiento Fetal , Lesiones Encefálicas/diagnóstico por imagen , Lesiones Encefálicas/etiología , Edad Gestacional , Encéfalo/diagnóstico por imagen
12.
Neonatology ; 120(6): 768-775, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37643585

RESUMEN

INTRODUCTION: There are data linking gestational diabetes mellitus (GDM) with adverse neurodevelopmental outcome in the offspring. We investigated the effect of GDM on microstructural brain development and neurodevelopmental outcome of very preterm infants. MATERIALS AND METHODS: Preterm infants <32 gestational weeks of mothers with GDM obtained cerebral magnetic resonance imaging (MRI) including diffusion-tensor imaging at term-equivalent age. For every infant, two gestational age-, sex-, and MRI scanner type-matched controls were included. Brain injury was assessed and fractional anisotropy (FA) and apparent diffusion coefficient (ADC) measured in 14 defined cerebral regions. Neurodevelopmental outcome was quantified at the corrected age of 24 months using the Bayley Scales of Infant Development. RESULTS: We included 47 infants of mothers with GDM and 94 controls. There were no differences in neonatal morbidity between the groups, nor in any type of brain injury. The GDM group showed significantly higher FA values in the centrum semiovale, the posterior limb of the internal capsule and the pons bilaterally, in the corpus callosum and the right occipital white matter, as well as lower ADC values in the right centrum semiovale, the right occipital white matter and the corpus callosum. Neurodevelopmental outcome did not differ between the groups. CONCLUSION: We found no impairment of brain development in GDM-exposed infants compared to matched controls, but differences in white matter microstructure in specific regions indicating an enhanced maturation. However, neurodevelopmental outcome was equal in both groups. Further studies are needed to better understand brain maturation in preterm infants exposed to GDM.


Asunto(s)
Lesiones Encefálicas , Diabetes Gestacional , Sustancia Blanca , Lactante , Femenino , Embarazo , Niño , Humanos , Recién Nacido , Preescolar , Recien Nacido Prematuro , Diabetes Gestacional/patología , Encéfalo/patología , Recién Nacido de muy Bajo Peso , Lesiones Encefálicas/diagnóstico por imagen , Lesiones Encefálicas/etiología , Lesiones Encefálicas/patología
13.
J Eat Disord ; 11(1): 35, 2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36879292

RESUMEN

BACKGROUND: Mostly, visual food stimuli paradigms for functional Magnetic Resonance Imaging are used in studies of eating disorders. However, the optimal contrasts and presentation modes are still under discussion. Therefore, we aimed to create and analyse a visual stimulation paradigm with defined contrast. METHODS: In this prospective study, a block-design fMRI paradigm with conditions of randomly altering blocks of high- and low-calorie food images and images of fixation cross was established. Food pictures were rated in advance by a group of patients diagnosed with anorexia nervosa to address the dedicated perception of patients with eating disorders. To optimize the scanning procedure and fMRI contrasts we have analysed neural activity differences between high-calorie stimuli versus baseline (H vs. X), low-calorie stimuli versus baseline (L vs. X) and high- versus low-calorie stimuli (H vs. L). RESULTS: By employing the developed paradigm, we were able to obtain results comparable to other studies and analysed them with different contrasts. Implementation of the contrast H versus X led to increased blood-oxygen-level-dependent signal (BOLD) mainly in unspecific areas, such as the visual cortex, the Broca´s area, bilaterally in the premotor cortex and the supplementary motor area, but also in thalami, insulae, the right dorsolateral prefrontal cortex, the left amygdala, the left putamen (p < .05). When applying the contrast L versus X, an enhancement of the BOLD signal was detected similarly within the visual area, the right temporal pole, the right precentral gyrus, Broca´s area, left insula, left hippocampus, the left parahippocampal gyrus, bilaterally premotor cortex and thalami (p < .05). Comparison of brain reactions regarding visual stimuli (high- versus low-calorie food), assumed to be more relevant in eating disorders, resulted in bilateral enhancement of the BOLD signal in primary, secondary and associative visual cortex (including fusiform gyri), as well as angular gyri (p < .05). CONCLUSIONS: A carefully designed paradigm, based on the subject's characteristics, can increase the reliability of the fMRI study, and may reveal specific brain activations elicited by this custom-built stimuli. However, a putative disadvantage of implementing the contrast of high- versus low-calorie stimuli might be the omission of some interesting outcomes due to lower statistical power. Trial registration NCT02980120.


Although the relationship with food is crucial for living, its underlying mechanisms (e.g., neurological, cognitive, physiological) are still not fully discovered. The development of functional magnetic resonance imaging made it possible to explore brain's responses to images of food. However, a proper methodological analysis of the research paradigm is still lacking. Here, we present the optimization of visual food stimuli paradigms achieved by comparison of neural activations of 20 female healthy adolescents after applying particular contrasts (i.e., high- versus low-calorie food images, high-calorie food images versus baseline, low-calorie food images versus baseline). Application of the contrast high- versus low-calorie food images resulted in stronger neural activation in visual cortex (including fusiform gyri) and angular gyri. This study highlights the importance of choosing a proper contrast regarding the study hypothesis, as it may induce more specific results. However, it may lead to loss of some outcomes, due to lower statistical power. Additionally, we have performed an evaluation of visual food stimuli chosen by patients diagnosed with anorexia nervosa. They have selected images of the most and the least willingly eaten meals. Although they didn't know the exact calorie content, they chose intuitively photos later classified as extremely high- or low-caloric.

14.
Cancers (Basel) ; 15(5)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36900177

RESUMEN

Different results have been reported concerning the relationship of the apparent diffusion coefficient (ADC) values and the status of methylation as the promoter gene for the enzyme methylguanine-DNA methyltransferase (MGMT) in patients with glioblastomas (GBs). The aim of this study was to investigate if there were correlations between the ADC values of the enhancing tumor and peritumoral areas of GBs and the MGMT methylation status. In this retrospective study, we included 42 patients with newly diagnosed unilocular GB with one MRI study prior to any treatment and histopathological data. After co-registration of ADC maps with T1-weighted sequences after contrast administration and dynamic susceptibility contrast (DSC) perfusion, we manually selected one region-of-interest (ROI) in the enhancing and perfused tumor and one ROI in the peritumoral white matter. Both ROIs were mirrored in the healthy hemisphere for normalization. In the peritumoral white matter, absolute and normalized ADC values were significantly higher in patients with MGMT-unmethylated tumors, as compared to patients with MGMT-methylated tumors (absolute values p = 0.002, normalized p = 0.0007). There were no significant differences in the enhancing tumor parts. The ADC values in the peritumoral region correlated with MGMT methylation status, confirmed by normalized ADC values. In contrast to other studies, we could not find a correlation between the ADC values or the normalized ADC values and the MGMT methylation status in the enhancing tumor parts.

15.
Eur J Radiol ; 161: 110722, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36758278

RESUMEN

AIMS: To determine the phase-contrast cardiovascular magnetic resonance imaging (PC-CMR) slice-position above aortic leaflet-attachment-plane (LAP) that provides flow-velocity, -volume and aortic valve area (AVA) measurements with best agreement to invasive and echocardiographic measurements in aortic stenosis (AS). METHODS AND RESULTS: Fifty-five patients with moderate/severe AS underwent cardiac catheterization, transthoracic echocardiography (TTE) and CMR. Overall, 171 image-planes parallel to LAP were measured via PC-CMR between 22 mm below and 24 mm above LAP. AVA via PC-CMR was calculated as flow-volume divided by peak-velocity during systole. Stroke volume (SV) and AVA were compared to volumetric SV and invasive AVA via the Gorlin-formula, respectively. Above LAP, SV by PC-CMR showed no significant dependence on image-plane-position and correlated strongly with volumetry (rho: 0.633, p < 0.001, marginal-mean-difference (MMD): 1 ml, 95 % confidence-interval (CI): -4 to 6). AVA assessed in image-planes 0-10 mm above LAP differed significantly from invasive measurement (MMD: -0.14 cm2, 95 %CI: 0.08-0.21). In contrast, AVA-values by PC-CMR measured 10-20 mm above LAP showed good agreement with invasive determination without significant MMD (0.003 cm2, 95 %CI: -0.09 to 0.09). Within these measurements, a plane 15 mm above LAP resulted in the lowest bias (MMD: 0.02 cm2, 95 %CI:-0.29 to 0.33). SV and AVA via TTE correlated moderately with volumetry (rho: 0.461, p < 0.001; bias: 15 ml, p < 0.001) and cardiac catheterization (rho: 0.486, p < 0.001, bias: -0.13 cm2, p < 0.001), respectively. CONCLUSION: PC-CMR measurements at 0-10 mm above LAP should be avoided due to significant AVA-overestimation compared to invasive determination. AVA-assessment by PC-CMR between 10 and 20 mm above LAP did not differ from invasive measurements, with the lowest intermethodical bias measured 15 mm above LAP.


Asunto(s)
Estenosis de la Válvula Aórtica , Válvula Aórtica , Humanos , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/patología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/patología , Imagen por Resonancia Magnética , Ecocardiografía , Volumen Sistólico
16.
Brain Sci ; 13(5)2023 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-37239270

RESUMEN

In the present study, we explore the role of attachment for microstructural white matter (WM) changes in adolescents with anorexia nervosa (AN) before and after exposure to short-term and nutritional treatment. The case sample consisted of 22 female adolescent inpatients with AN (mean age: 15.2 ± 1.2 years) and the control sample were 18 gender-matched healthy adolescents (mean age: 16.8 ± 0.9 years). We performed a 3T MRI in the patient group during the acute state of AN and after weight restoration (duration: 2.6 ± 1 months) and compared the data to a healthy control group. To classify attachment patterns, we used the Adult Attachment Projective Picture System. In the patient sample, over 50% were classified with an attachment trauma/unresolved attachment status. Prior to treatment exposure, fractional anisotropy (FA) reductions and concordant mean diffusivity (MD) increases were evident in the fornix, the corpus callosum and WM regions of the thalamus, which normalized in the corpus callosum and the fornix post-therapy in the total patient sample (p < 0.002). In the acute state, patients with an attachment trauma demonstrated significant FA decreases compared to healthy controls, but no MD increases, in the corpus callosum and cingulum bilaterally, which remained decreased after therapy. Attachment patterns seem to be associated with region-specific changes of WM alterations in AN.

17.
J Neurophysiol ; 107(1): 134-47, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21975446

RESUMEN

Studies with patients and functional magnetic resonance imaging investigations have demonstrated that the cerebellum plays an essential role in adaptation to visuomotor rotation and force field perturbation. To identify cerebellar structures involved in the two tasks, we studied 19 patients with focal lesions after cerebellar infarction. Focal lesions were manually traced on magnetic resonance images and normalized using a new spatially unbiased template of the cerebellum. In addition, we reanalyzed data from 14 patients with cerebellar degeneration using voxel-based morphometry. We found that adjacent regions with only little overlap in the anterior arm area (lobules IV to VI) are important for adaptation in both tasks. Although adaptation to the force field task lay more anteriorly (lobules IV and V), lobule VI was more important for the visuomotor task. In addition, regions in the posterolateral cerebellum (Crus I and II) contributed to both tasks. No consistent involvement of the posterior arm region (lobule VIII) was found. Independence of the two kinds of adaptation is further supported by findings that performance in one task did not correlate to performance in the other task. Our results show that the anterior arm area of the cerebellum is functionally divided into a more posterior part of lobule VI, extending into lobule V, related to visuomotor adaption, and a more anterior part including lobules IV and V, related to force field adaption. The posterolateral cerebellum may process common aspects of both tasks.


Asunto(s)
Enfermedades Cerebelosas/fisiopatología , Cerebelo/fisiopatología , Movimiento , Red Nerviosa/fisiopatología , Plasticidad Neuronal , Percepción Visual , Adaptación Fisiológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Neurológicos
18.
Cancers (Basel) ; 14(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35804969

RESUMEN

Preoperative grade prediction is important in diagnostics of glioma. Even more important can be follow-up after chemotherapy and radiotherapy of high grade gliomas. In this review we provide an overview of MR-spectroscopy (MRS), technical aspects, and different clinical scenarios in the diagnostics and follow-up of gliomas in pediatric and adult populations. Furthermore, we provide a recap of the current research utility and possible future strategies regarding proton- and phosphorous-MRS in glioma research.

19.
Front Neurol ; 13: 831537, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295831

RESUMEN

Background: Acute changes of cerebral energy metabolism in early brain injury (EBI) after aneurysmal subarachnoid hemorrhage (aSAH) may play a crucial role for overall neurological outcome. However, direct detection of these alterations is limited. Phosphorous magnetic resonance spectroscopy (31P-MRS) is a molecular-based advanced neuroimaging technique allowing measurements of pathophysiological processes and tissue metabolism based on various phosphorous compound metabolites. This method may provide objective assessment of both primary and secondary changes. Objective: The aim of this pilot study was to evaluate the feasibility and the diagnostic potential of early 31P-MRS in aSAH. Methods: Patients with aSAH treated for ruptured aneurysms between July 2016 and October 2017 were prospectively included in the study. 3-Tesla-MRI including 31P-MRS was performed within the first 72 h after hemorrhage. Data of the vascular territories of the anterior, middle, and posterior cerebral arteries (ACA, MCA, PCA) and the basal ganglia were separately analyzed and compared with data of a healthy age- and sex-matched control group. Phosphorous compound metabolites were quantified, and ratios of these metabolites were further evaluated. Influence of treatment modality, clinical conditions, and analgosedation were analyzed. Results: Data of 13 patients were analyzed. 31P-MRS showed significant changes in cerebral energy metabolism after aSAH in all cerebrovascular territories. Both PCr/ATP and PCr/Pi ratio were notably increased (P < 0.001). Also, Pi/ATP was significantly decreased in all cerebrovascular territories (P = 0.014). PME/PDE ratio was overall significant decreased (P < 0.001). Conclusion: 31P-MRS is a promising non-invasive imaging tool for the assessment of changes in energy metabolism after aSAH. It allows a detailed insight into EBI and seems to harbor a high potential for clinical practice.

20.
Artif Intell Med ; 132: 102384, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36207089

RESUMEN

Segmentation of specific brain tissue from MRI volumes is of great significance for brain disease diagnosis, progression assessment, and monitoring of neurological conditions. Manual segmentation is time-consuming, laborious, and subjective, which significantly amplifies the need for automated processes. Over the last decades, the active development in the field of deep learning, especially convolutional neural networks (CNNs), and the associated performance improvements have increased the demand for the application of CNN-based methods to provide consistent measurements and quantitative analyses. In this paper, we present an efficient deep learning approach for the segmentation of brain tissue. More specifically, we address the problem of segmentation of the posterior limb of the internal capsule (PLIC) in preterm neonates. To this end, we propose a CNN-based pipeline comprised of slice-selection modules and a multi-view segmentation model, which exploits the 3D information contained in the MRI volumes to improve segmentation performance. One special feature of the proposed method is its ability to identify one desired slice out of the whole image volume, which is relevant for pediatricians in terms of prognosis. To increase computational efficiency, we apply a strategy that automatically reduces the information contained in the MRI volumes to its relevant parts. Finally, we conduct an expert rating alongside standard evaluation metrics, such as dice score, to evaluate the performance of the proposed framework. We demonstrate the benefit of the multi-view technique by comparing it with its single-view counterparts, which reveals that the proposed method strikes a good balance between exploiting the available image information and reducing the required computing power compared to 3D segmentation networks. Standard evaluation metrics as, well as expert-based assessment, confirm the good performance of the proposed framework, with the latter being more relevant in terms of clinical applicability. We demonstrate that the proposed deep learning pipeline can compete with the experts in terms of accuracy. To prove the generalisability of the proposed method, we additionally assess our deep learning pipeline to data from the Developing Human Connectome Project (dHCP).


Asunto(s)
Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Recién Nacido , Cápsula Interna , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación
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