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1.
Cereb Cortex ; 33(11): 6852-6861, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-36807411

RESUMO

Prenatal alcohol exposure (PAE) can change the normal trajectory of human fetal brain development and may lead to long-lasting neurodevelopmental changes in the form of fetal alcohol spectrum disorders. Currently, early prenatal patterns of alcohol-related central nervous system changes are unclear and it is unknown if small amounts of PAE may result in early detectable brain anomalies. This super-resolution fetal magnetic resonance imaging (MRI) study aimed to identify regional effects of PAE on human brain structure. Fetuses were prospectively assessed using atlas-based semi-automated 3-dimensional tissue segmentation based on 1.5 T and 3 T fetal brain MRI examinations. After expectant mothers completed anonymized PRAMS and TACE questionnaires for PAE, fetuses without gross macroscopic brain abnormalities were identified and analyzed. Linear mixed-effects modeling of regional brain volumes was conducted and multiple comparisons were corrected using the Benjamini-Hochberg procedure. In total, 500 pregnant women were recruited with 51 reporting gestational alcohol consumption. After excluding confounding comorbidities, 24 fetuses (26 observations) were identified with PAE and 52 age-matched controls without PAE were analyzed. Patients with PAE showed significantly larger volumes of the corpus callosum (P ≤ 0.001) and smaller volumes of the periventricular zone (P = 0.001). Even minor (1-3 standard drinks per week) PAE changed the neurodevelopmental trajectory.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Humanos , Gravidez , Feminino , Efeitos Tardios da Exposição Pré-Natal/diagnóstico por imagem , Encéfalo , Feto/diagnóstico por imagem , Corpo Caloso , Imageamento por Ressonância Magnética/métodos
2.
Cereb Cortex ; 33(9): 5613-5624, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36520481

RESUMO

Measuring and understanding functional fetal brain development in utero is critical for the study of the developmental foundations of our cognitive abilities, possible early detection of disorders, and their prevention. Thalamocortical connections are an intricate component of shaping the cortical layout, but so far, only ex-vivo studies provide evidence of how axons enter the sub-plate and cortex during this highly dynamic phase. Evidence for normal in-utero development of the functional thalamocortical connectome in humans is missing. Here, we modeled fetal functional thalamocortical connectome development using in-utero functional magnetic resonance imaging in fetuses observed from 19th to 40th weeks of gestation (GW). We observed a peak increase of thalamocortical functional connectivity strength between 29th and 31st GW, right before axons establish synapses in the cortex. The cortico-cortical connectivity increases in a similar time window, and exhibits significant functional laterality in temporal-superior, -medial, and -inferior areas. Homologous regions exhibit overall similar mirrored connectivity profiles, but this similarity decreases during gestation giving way to a more diverse cortical interconnectedness. Our results complement the understanding of structural development of the human connectome and may serve as the basis for the investigation of disease and deviations from a normal developmental trajectory of connectivity development.


Assuntos
Córtex Cerebral , Conectoma , Humanos , Tálamo , Imageamento por Ressonância Magnética/métodos , Encéfalo , Desenvolvimento Fetal , Conectoma/métodos , Vias Neurais
3.
Cereb Cortex ; 31(9): 4024-4037, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-33872347

RESUMO

Genetic, molecular, and physical forces together impact brain morphogenesis. The early impact of deficient midline crossing in agenesis of the Corpus Callosum (ACC) on prenatal human brain development and architecture is widely unknown. Here we analyze the changes of brain structure in 46 fetuses with ACC in vivo to identify their deviations from normal development. Cases of complete ACC show an increase in the thickness of the cerebral wall in the frontomedial regions and a reduction in the temporal, insular, medial occipital and lateral parietal regions, already present at midgestation. ACC is associated with a more symmetric configuration of the temporal lobes and increased frequency of atypical asymmetry patterns, indicating an early morphomechanic effect of callosal growth on human brain development affecting the thickness of the pallium along a ventro-dorsal gradient. Altered prenatal brain architecture in ACC emphasizes the importance of conformational forces introduced by emerging interhemispheric connectivity on the establishment of polygenically determined brain asymmetries.


Assuntos
Agenesia do Corpo Caloso/patologia , Encéfalo/embriologia , Feto/patologia , Lateralidade Funcional , Adulto , Agenesia do Corpo Caloso/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Córtex Cerebral/embriologia , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/patologia , Corpo Caloso/embriologia , Corpo Caloso/crescimento & desenvolvimento , Corpo Caloso/patologia , Feminino , Feto/diagnóstico por imagem , Idade Gestacional , Humanos , Imageamento por Ressonância Magnética , Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos , Lobo Temporal/embriologia , Lobo Temporal/crescimento & desenvolvimento , Lobo Temporal/patologia
4.
Cereb Cortex ; 31(8): 3713-3722, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33772541

RESUMO

Knowledge about structural brain asymmetries of human fetuses with body lateralization defects-congenital diseases in which visceral organs are partially or completely incorrectly positioned-can improve our understanding of the developmental origins of hemispheric brain asymmetry. This study investigated structural brain asymmetry in 21 fetuses, which were diagnosed with different types of lateralization defects; 5 fetuses with ciliopathies and 26 age-matched healthy control cases, between 22 and 34 gestational weeks of age. For this purpose, a database of 4007 fetal magnetic resonance imagings (MRIs) was accessed and searched for the corresponding diagnoses. Specific temporal lobe brain asymmetry indices were quantified using in vivo, super-resolution-processed MR brain imaging data. Results revealed that the perisylvian fetal structural brain lateralization patterns and asymmetry indices did not differ between cases with lateralization defects, ciliopathies, and normal controls. Molecular mechanisms involved in the definition of the right/left body axis-including cilium-dependent lateralization processes-appear to occur independently from those involved in the early establishment of structural human brain asymmetries. Atypically inverted early structural brain asymmetries are similarly rare in individuals with lateralization defects and may have a complex, multifactorial, and neurodevelopmental background with currently unknown postnatal functional consequences.


Assuntos
Encéfalo/anormalidades , Encéfalo/embriologia , Feto/anormalidades , Lateralidade Funcional/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Cílios/fisiologia , Estudos de Coortes , Feminino , Feto/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Gravidez , Terminologia como Assunto
5.
Prenat Diagn ; 40(1): 110-124, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31802515

RESUMO

Human cytomegalovirus (CMV) is an ubiquitous pathogen, with a high worldwide seroprevalence. When acquired in the prenatal period, congenital CMV (cCMV) is a major cause of neurodevelopmental sequelae and hearing loss. cCMV remains an underdiagnosed condition, with no systematic screening implemented in pregnancy or in the postnatal period. Therefore, imaging takes a prominent role in prenatal diagnosis of cCMV. With the prospect of new viable therapies, accurate and timely diagnosis becomes paramount, as well as identification of fetuses at risk for neurodevelopmental sequelae. Fetal magnetic resonance imaging (MRI) provides a complementary method to ultrasound (US) in fetal brain and body imaging. Anterior temporal lobe lesions are the most specific finding, and MRI is superior to US in their detection. Other findings such as ventriculomegaly, cortical malformations and calcifications, as well as hepatosplenomegaly, liver signal changes and abnormal effusions are unspecific. However, when seen in combination these should raise the suspicion of fetal infection, highlighting the need for a full fetal assessment. Still, some fetuses deemed normal on prenatal imaging are symptomatic at birth or develop delayed cCMV-associated symptoms, leaving room for improvement of diagnostic tools. Advanced MR sequences may help in this field and in determining prognosis, but further studies are needed.


Assuntos
Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/diagnóstico por imagem , Hidrocefalia/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Encefalopatias/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Deficiências do Desenvolvimento , Imagem de Tensor de Difusão/métodos , Feminino , Doenças Fetais/diagnóstico por imagem , Perda Auditiva Neurossensorial , Hepatomegalia/diagnóstico por imagem , Humanos , Espectroscopia de Ressonância Magnética/métodos , Placenta/diagnóstico por imagem , Gravidez , Diagnóstico Pré-Natal/métodos , Esplenomegalia/diagnóstico por imagem
6.
Prenat Diagn ; 40(1): 6-17, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31618472

RESUMO

Fetal MRI is an increasingly used tool in the field of prenatal diagnosis. While US remains the first line screening tool, as an adjuvant imaging tool, MRI has been proven to increase diagnostic accuracy and change patient counseling. Further, there are instances when US may not be sufficient for diagnosis. As a multidisciplinary field, it is important that every person involved in the referral, diagnosis, counseling and treatment of the patients is familiar with the basic principles, indications and findings of fetal MRI. The purpose of the current paper is to equip radiologists and non-radiologists with basic MRI principles and essential topics in patient preparation and provide illustrative examples of when fetal MRI may be used. This aims to aid the referring clinician in better selecting and improve patient counseling prior to arrival in the radiology department and, ultimately, patient care.


Assuntos
Doenças Fetais/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Feminino , Feto/diagnóstico por imagem , Neuroimagem Funcional/métodos , Humanos , Campos Magnéticos , Espectroscopia de Ressonância Magnética/métodos , Gravidez , Diagnóstico Pré-Natal , Ondas de Rádio , Ultrassonografia Pré-Natal
7.
Radiology ; 292(1): 159-169, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31084478

RESUMO

Background The cortical plate (future cortex) is readily identifiable in utero at MRI. However, MRI evaluation of the remaining brain layers is limited by the poor T2 contrast between the subplate and the underlying intermediate zone (IZ). Purpose To compare the delineation of fetal brain lamination between T2-weighted single-shot fast spin-echo (SSFSE) and echo-planar imaging (EPI) fluid-attenuated inversion recovery (FLAIR) images, and to quantify differences in the depiction of brain layering between the two sequences. Materials and Methods Consecutive fetal brain MRI examinations performed between January 2014 and March 2018 with T2-weighted SSFSE and EPI-FLAIR images were reviewed. Two neuroradiologists evaluated the visibility of brain layers by using a three-point grading system, and findings were compared by using the sign test. One rater performed region-of-interest analysis in the cortical plate (CP), subplate (gyral crest and sulcal bottom), and IZ. Signal intensity (SI) ratios between adjacent brain compartments were calculated and compared by using the paired t test. Reader agreement was assessed by using weighted κ values. Results A total of 259 MRI examinations (mean gestational age [GA], 26.9 weeks ± 5.6) were included in the qualitative analysis, and 72 MRI examinations (mean GA, 27.4 weeks ± 5.5) were included in the quantitative analysis. Subplate identification on EPI-FLAIR images was superior to that on T2-weighted SSFSE images (subplate visualization [complete + partial]: frontal lobe, n = 243 vs n = 117; temporal lobe, n = 244 vs n = 137; parietal lobe n = 240 vs n = 93; and occipital lobe, n = 241 vs n = 97, respectively; P < .001), with higher interrater reliability (κ = 0.91-0.95 for EPI-FLAIR images and 0.80-0.87 for T2-weighted SSFSE images). SI ratios between the IZ and subplate were significantly higher on EPI-FLAIR images in all lobes (EPI-FLAIR images: 1.6-2.1; T2-weighted SSFSE images:1.2-1.2; P < .001). Subplate-to-CP ratios were not statistically significant between the two sequences (EPI-FLAIR:1.8-2.4; T2-weighted SSFSE: 2.0-2.2; P < .001). Conclusion The echo-planar fluid-attenuated inversion recovery sequence improves visualization of fetal brain lamination compared with the T2-weighted single-shot fast spin-echo sequence, as established by quantitative and qualitative methods. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Rossi in this issue.


Assuntos
Córtex Cerebral/anatomia & histologia , Córtex Cerebral/embriologia , Imagem Ecoplanar/métodos , Imageamento por Ressonância Magnética/métodos , Estudos de Coortes , Feminino , Humanos , Gravidez , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos
8.
Eur Radiol ; 29(12): 7063-7072, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31286188

RESUMO

OBJECTIVES: The software "SyMRI" generates different MR contrasts and characterizes tissue properties based on a single acquisition of a multi-dynamic multi-echo (MDME)-FLAIR sequence. The aim of this study was to assess the applicability of "SyMRI" in the assessment of myelination in preterm and term-born neonates. Furthermore, "SyMRI" was compared with conventional MRI. METHODS: A total of 30 preterm and term-born neonates were examined at term-equivalent age using a standardized MRI protocol. MDME sequence (acquisition time, 5 min, 24 s)-based post-processing was performed using "SyMRI". Myelination was assessed by scoring seven brain regions on quantitative T1-/T2-maps, generated by "SyMRI" and on standard T1-/T2-weighted images, acquired separately. Analysis of covariance (ANCOVA) (covariate, gestational age (GA) at MRI (GAMRI)) was used for group comparison. RESULTS: In 25/30 patients (83.3%) (18 preterm and seven term-born neonates), "SyMRI" acquisitions were successfully performed. "SyMRI"-based myelination scores were significantly lower in preterm compared with term-born neonates (ANCOVA: T1: F(1, 22) = 7.420, p = 0.012; T2: F(1, 22) = 5.658, p = 0.026). "SyMRI"-based myelination scores positively correlated with GAMRI (T1: r = 0.662, n = 25, p ≤ 0.001; T2: r = 0.676, n = 25, p ≤ 0.001). The myelination scores based on standard MRI did not correlate with the GAMRI. No significant differences between preterm and term-born neonates were detectable. CONCLUSIONS: "SyMRI" is a highly promising MR technique for neonatal brain imaging. "SyMRI" is superior to conventional MR sequences in the visual detection of delayed myelination in preterm neonates. KEY POINTS: • By providing multiple MR contrasts, "SyMRI" is a time-saving method in neonatal brain imaging. • Differences concerning the myelination in term-born and preterm infants are visually detectable on T1-/T2-weighted maps generated by "SyMRI". • "SyMRI" allows a faster and more sensitive assessment of myelination compared with standard MR sequences.


Assuntos
Encéfalo/diagnóstico por imagem , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética/métodos , Software , Meios de Contraste/farmacologia , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Fibras Nervosas Mielinizadas
9.
Pediatr Neurosurg ; 54(4): 258-264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31266045

RESUMO

Prenatal counselling following the diagnosis of fetal ventriculomegaly is challenging. Fetal MRI (magnetic resonance imaging) can be helpful in characterizing ventriculomegaly severity and associated anomalies, hence contributing to prognosis establishment. Choroid plexus hyperplasia (CPH) is a rare entity characterized by enlargement of the choroid plexuses, usually progressing to severe hydrocephalus with an associated poor outcome. We present a case of CPH diagnosed by fetal MRI at 23 weeks of gestation following referral for ventriculomegaly. The pregnancy was carried to term and the child was monitored clinically and radiologically. Despite the persistence of enlarged choroid plexuses, the ventricular size has progressively decreased, and at the 4-year follow-up the child presented normal psychomotor development. This case highlights the added value of MRI in prenatal diagnosis of fetal ventriculomegaly and its management. The unusual benign outcome in this case can be considered for parental counselling when faced with a fetus with similar findings.


Assuntos
Plexo Corióideo , Feto/anormalidades , Hidrocefalia/diagnóstico , Diagnóstico Pré-Natal , Ventrículos Cerebrais/patologia , Pré-Escolar , Feminino , Humanos , Hiperplasia , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Gravidez , Prognóstico , Ultrassonografia Pré-Natal
11.
Animals (Basel) ; 14(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38396604

RESUMO

The use of recombinant bovine somatotropin (rbST) leads to an increase in variable amounts of milk production in buffalo, but there is a lack of information on the influence of rbST on their metabolism. This study looked at the effects of a single 500 mg dose of rbST on the lipid profile, liver and kidney function, and physical, chemical, and cellular constitution of milk in 14 buffalo over 14 days, from the 100th day of lactation, compared with 14 animals in a control group. From the first day after rbST, there was a rise in beta-hydroxybutyrate (ß-HBO), possibly due to higher dry matter intake or the biotransformation of NEFA into ß-HBO. The treatment did not influence blood glucose, non-esterified fatty acids (NEFAs), triglycerides, cholesterol, total protein, albumin, AST, GGT, bilirubin, urea, or creatinine levels. In 71.3% of the buffalo, there was a gradual increase in milk production, with the maximal response occurring in the first week followed by a gradual decrease, whilst in 21.4%, the increase in production occurred between 7 and 10 days. Only 7.1% of the animals did not respond. On the 3rd, 5th, 7th, and 10th days after treatment, an increase was found in daily milk production between the two groups equal to 1.04, 1.52, 1.42, and 1.06 L, respectively. In relative terms, this means an increase in milk production, respectively, of 15.1%, 21.0%, 19.8%, and 15.1%. The constitution of the milk showed no difference in the amounts of fat, lactose, total solids, or somatic cell count; however, on the third day after rbST administration, there was a decrease in protein. Notably, from the fifth day, the protein values showed no statistical difference. It can be concluded that the use of rbST in buffalo from the 100th day of lactation is metabolically safe since the treatment neither caused imbalances in fat metabolism nor overloaded the liver or renal function, and the changes in milk composition were transient and limited to a decrease in milk protein.

12.
Clin Neuroradiol ; 34(2): 421-429, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38289377

RESUMO

PURPOSE: Neonates born at < 28 weeks of gestation are at risk for neurodevelopmental delay. The aim of this study was to identify quantitative MR-based metrics for the prediction of neurodevelopmental outcomes in extremely preterm neonates. METHODS: T1-/T2-relaxation times (T1R/T2R), ADC, and fractional anisotropy (FA) of the left/right posterior limb of the internal capsule (PLIC) and the brainstem were determined at term-equivalent ages in a sample of extremely preterm infants (n = 33). Scores for cognitive, language, and motor outcomes were collected at one year corrected-age. Pearson's correlation analyses detected relationships between quantitative measures and outcome data. Stepwise regression procedures identified imaging metrics to estimate neurodevelopmental outcomes. RESULTS: Cognitive outcomes correlated significantly with T2R (r = 0.412; p = 0.017) and ADC (r = -0.401; p = 0.021) (medulla oblongata). Furthermore, there were significant correlations between motor outcomes and T1R (pontine tegmentum (r = 0.346; p = 0.049), midbrain (r = 0.415; p = 0.016), right PLIC (r = 0.513; p = 0.002), and left PLIC (r = 0.504; p = 0.003)); T2R (right PLIC (r = 0.405; p = 0.019)); ADC (medulla oblongata (r = -0.408; p = 0.018) and pontine tegmentum (r = -0.414; p = 0.017)); and FA (pontine tegmentum (r = -0.352; p = 0.045)). T2R/ADC (medulla oblongata) (cognitive outcomes (R2 = 0.296; p = 0.037)) and T1R (right PLIC)/ADC (medulla oblongata) (motor outcomes (R2 = 0.405; p = 0.009)) revealed predictive potential for neurodevelopmental outcomes. CONCLUSION: There are relationships between relaxometry­/DTI-based metrics determined by neuroimaging near term and neurodevelopmental outcomes collected at one year of age. Both modalities bear prognostic potential for the prediction of cognitive and motor outcomes. Thus, quantitative MRI at term-equivalent ages represents a promising approach with which to estimate neurologic development in extremely preterm infants.


Assuntos
Lactente Extremamente Prematuro , Imageamento por Ressonância Magnética , Humanos , Recém-Nascido , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/etiologia , Cápsula Interna/diagnóstico por imagem , Valor Preditivo dos Testes
13.
Animals (Basel) ; 12(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35739897

RESUMO

The aim of the present study is to evaluate the erythrogram and iron serum profiles of neonatal calves born spontaneously or born by elective cesarean section with or without dexamethasone induction. The research was performed on 38 newborn Nellore calves. Three groups of calves were assigned according to the type of birth: calves born by spontaneous vaginal calving (n = 10), calves born by elective cesarean section without inducing labor (n = 14), and calves born by elective cesarean section with labor induction with dexamethasone (n = 14). Blood samples to assess red blood cell count (RBC), hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), concentration of mean corpuscular hemoglobin (MCHC), serum iron (SFe), total capacity to bind iron to transferrin (TIBIC), and transferrin saturation index (TSI) were performed at calving (0, 3, 6, and 12 h of life) and on 1, 2, 3, 5, 7, 10, 15, and 30 days of life. Regardless of the experimental group (calves born spontaneously, or born by elective cesarean section with or without dexamethasone induction), in the first day of life there was a decrease in the number of red blood cells, hemoglobin rates, and values of the globular volume. In the period of the first 10 days of life, animals from spontaneous vaginal delivery quickly recovered values of erythrocytes, hemoglobin, and packed cell volume, whereas animals born by elective C-section (induced and uninduced) did not recover as quickly in their rates of hemoglobin and packed cell volume values. In calves born by elective C-section (induced and uninduced), it was observed in their period between 10 and 30 days of life that the MCV and MCH were reduced by passing the presenting microcytic hypochromic when compared with calves obtained by spontaneous vaginal delivery. In the period between 10 and 30 days of life, the levels of SFe and TSI in animals born by elective C-section (induced and uninduced) are significantly lower. The differences in the erythrogram values between Nellore calves born spontaneously and those by elective C-section with or without induction must be considered consequent to the process of neonatal adaptation to extrauterine life. Iron supplementation in the first month of life in calves from cesarean could be recommended to prevent anemia of this iron deficiency.

14.
Clin Neuroradiol ; 31(2): 315-323, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32161995

RESUMO

PURPOSE: The purpose of this study was to assess the diagnostic accuracy of T1-weighted and T2-weighted contrasts generated by the MR data postprocessing software SyMRI (Synthetic MR AB, Linköping, Sweden) for neonatal brain imaging. METHODS: In this study 36 cases of neonatal MRI were retrospectively collected, which included T1-weighted and T2-weighted sequences as well as multi-dynamic multi-echo (MDME) sequences. Of the 36 neonates 32 were included in this study and 4 neuroradiologists independently assessed neonatal brain examinations on the basis of conventional and SyMRI-generated T1-weighted and T2-weighted contrasts, in order to determine the presence or absence of lesions. The sensitivity and specificity of both methods were calculated and compared. RESULTS: Compared to conventionally acquired T1 and T2-weighted images, SyMRI-generated contrasts showed a lower sensitivity but a higher specificity (SyMRI sensitivity 0.88, confidence interval (CI): 0.72-0.95; specificity 1, CI: 0.89-1/conventional MRI: sensitivity: 0.94, CI: 0.80-0.98; specificity: 0.94, CI: 0.80-0.98). CONCLUSION: The T1-weighted and T2-weighted images generated by SyMRI showed a diagnostic accuracy comparable to that of conventionally acquired contrasts. In addition to semiquantitative imaging data, SyMRI provides diagnostic images and leads to a more efficient use of available imaging time in neonatal brain MRI.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Meios de Contraste , Feminino , Humanos , Recém-Nascido , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
J Clin Med ; 9(11)2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114485

RESUMO

Dental anomalies coincide with genetic disorders, and prenatal identification may contribute to a more accurate diagnosis. The aim of this study was to assess whether fetal Magnet Resonance Imaging (MRI) is suitable to visualize and investigate intrauterine dental development in the upper jaw, and to compare the quality of visibility of tooth buds between 1.5 Tesla (T) and 3T images. MR images of fetuses Gestational Week (GW) 26.71 ± 4.97 from 286 pregnant women with diagnoses unrelated to dental anomalies were assessed by three raters. We compared the visibility between groups and field strengths in five gestational age groups, using chi square and Fisher's exact tests. All ten primary tooth buds were identifiable in 5.4% at GW 18-21, in 75.5% at GW 26-29, and in 90.6% at GW 34+. Before GW 30, more tooth buds were identifiable on 3T images than on 1.5T images. Statistical significance was only reached for identification of incisors (p = 0.047). Therefore, 1.5T and 3T images are viable to visualize tooth buds, particularly after GW 25, and their analysis may serve as diagnostic criterion. MRI tooth bud data might have an impact on various fields of research, such as the maldevelopment of teeth and their causes. Analyzing tooth buds as an additional diagnostic criterion is not time consuming, and could lead to an improvement of syndrome diagnosis.

16.
Neuroradiol J ; 32(3): 179-188, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30777482

RESUMO

BACKGROUND: Computed tomography (CT) perfusion has been studied as a tool to predict delayed cerebral ischemia (DCI) and clinical outcome in spontaneous subarachnoid hemorrhage (SAH). The purpose of the study was to determine whether quantitative CT perfusion performed within 72 hours after admission can predict the occurrence of DCI and clinical outcome as measured with a modified Rankin scale (mRS) at 3 months after ictus. METHODS: Cerebral perfusion was assessed in a prospective cohort of patients with acute SAH. CT perfusion parameters at <72 h post SAH were quantitatively measured in the main vascular territories and represented as whole-brain means. Spearman rank correlation coefficient and generalized additive regression models for binary outcome were used. RESULTS: A total of 66 patients underwent CT perfusion at <72 h. Poor clinical grade on admission was correlated with worse cerebral perfusion in all parameters. Multivariable analysis yielded an association of time to peak (TTP; odds ratio (OR) = 0.89; 95% confidence interval (CI): 0.77, 1.02; p = 0.083) with the occurrence of DCI. We also found an association of TTP values with poor outcome, with an 8% increase in the odds of mRS > 3 for each one second increase in TTP at admission (OR = 1.08; 95% CI: 1.00, 1.17; p = 0.061). CONCLUSIONS: We identified an association of early TTP changes with DCI and poor clinical outcome. However, there were no associations with cerebral blood flow or mean transit time and DCI/clinical outcome. CT perfusion still remains to be validated as a tool in predicting outcome in SAH.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Angiografia Cerebral/métodos , Angiografia por Tomografia Computadorizada/métodos , Hemorragia Subaracnóidea/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Isquemia Encefálica/fisiopatologia , Meios de Contraste , Feminino , Humanos , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Interpretação de Imagem Radiográfica Assistida por Computador , Recuperação de Função Fisiológica , Hemorragia Subaracnóidea/fisiopatologia , Fatores de Tempo
17.
J Neurointerv Surg ; 9(7): 698-701, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27365143

RESUMO

BACKGROUND: Basilar tip aneurysms (BTA) are multifactorial in origin, with luminal forces playing a major role in their formation. Considering the reduced hemodynamic stress on the basilar apex in the fetal-type posterior cerebral artery (fPCA), we hypothesize that BTA should be less common in patients with this variant. OBJECTIVE: To investigate, in a retrospective case-control study, the frequency of fPCA in patients with and without BTA. MATERIALS AND METHODS: We collected clinical and imaging data from consecutive patients with BTA undergoing catheter angiography between July 2010 and July 2015, and from a randomly selected, age- and sex-matched non-BTA control population from our prospective database. Anatomical variants of the distal basilar artery region were assessed in the two groups and compared using parametric and non-parametric tests. RESULTS: Fifty-nine BTA cases and 337 controls were included. fPCA was present in 3% of patients with BTA and 23% in the control group (p<0.001; OR=0.11, 95% CI 0.03 to 0.48). Basilar tip disposition was cranial in 49% of BTA and 63% of non-BTA cases (p=0.04; OR=0.57, 95% CI 0.33 to 0.99); a caudal disposition was found in 24% and 6% of cases, respectively (p<0.001; OR=4.65, 95% CI 2.21 to 9.80). CONCLUSIONS: We found a statistically significant association between the absence of fPCA and BTA. Our findings underline the importance of hemodynamic stress in the formation of intracranial aneurysms, and suggest that fPCA is a protective variant for formation of BTA.


Assuntos
Artéria Basilar/diagnóstico por imagem , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/epidemiologia , Artéria Cerebral Posterior/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Angiografia Cerebral/métodos , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Estudos Retrospectivos
18.
Br J Radiol ; 90(1069): 20160362, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27768394

RESUMO

Fetal MR now plays an important role in the clinical work-up of pregnant females. It is performed mainly at 1.5 T. However, the desire to obtain a more precise fetal depiction or the fact that some institutions have access only to a 3.0 T scanner has resulted in a growing interest in performing fetal MR at 3.0 T. The aim of this article was to provide a reference for the use of 3.0 T MRI as a prenatal diagnostic method.


Assuntos
Imagem de Tensor de Difusão , Doenças Fetais/diagnóstico , Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal/métodos , Feminino , Humanos , Gravidez , Doses de Radiação , Medição de Risco , Sensibilidade e Especificidade
19.
Brain Lang ; 174: 9-15, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28709112

RESUMO

Situs inversus totalis is a rare condition where the visceral organs are organized as a mirror image of default organ position. In this study we picture the co-development between brain and visceral organs in a case of situs inversus totalis from a fetal stage to adolescence and compare our findings to an age-, gender-, and education-matched control with normal position of thoracic and abdominal organs. We show that in this case of situs inversus, functional and structural brain lateralization do not coincide with visceral organ situs. Furthermore, cognitive development in situs inversus is normal. To our knowledge, this is the first report of antenatal cerebral origins of structural and functional brain asymmetry in a case of situs inversus totalis.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Lateralidade Funcional , Idioma , Situs Inversus/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Cognição/fisiologia , Alemanha , Humanos , Lactente , Recém-Nascido , Masculino
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