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1.
Ultrasound Obstet Gynecol ; 61(5): 601-609, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36445348

RESUMO

OBJECTIVE: To investigate human femur development in fetal growth restriction (FGR) by analyzing femur morphometrics and distal epimetaphyseal features on prenatal magnetic resonance imaging (MRI). METHODS: This was a retrospective study of 111 fetuses (mean gestational age (GA), 27 + 2 weeks (range, 19-35 weeks)) with FGR associated with placental insufficiency without other major abnormalities and 111 GA-matched normal controls. On 1.5-Tesla echoplanar MRI, femur morphometrics, including diaphyseal length, epiphyseal length and epiphyseal width, were assessed. Using a previously reported grading system, epimetaphyseal features, including cartilaginous epiphyseal shape, metaphyseal shape and epiphyseal ossification, were analyzed qualitatively. To compare FGR cases and controls, the paired t-test was used to assess morphometrics, generalized estimating equations were used for epimetaphyseal features and time-to-event analysis was used to assess the visibility of epiphyseal ossification. RESULTS: There were significant differences in femur morphometrics between FGR cases and controls (all parameters, P < 0.001), with bone shortening observed in FGR. No significant differences were found in the distribution of epimetaphyseal features between FGR cases and controls (epiphyseal shape, P = 0.341; metaphyseal shape, P = 0.782; epiphyseal ossification, P = 0.85). Epiphyseal ossification was visible at a median of 33.6 weeks in FGR cases and at 32.1 weeks in controls (P = 0.008). CONCLUSIONS: On prenatal MRI, cases with FGR associated with placental insufficiency exhibit diaphyseal and epiphyseal shortening of the femur. However, FGR cases and normal controls share similarly graded distal epimetaphyseal features. Consequently, these features may not be appropriate MRI characteristics for the identification of FGR. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Retardo do Crescimento Fetal , Insuficiência Placentária , Gravidez , Feminino , Humanos , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/patologia , Insuficiência Placentária/diagnóstico por imagem , Placenta/diagnóstico por imagem , Estudos Retrospectivos , Fêmur/diagnóstico por imagem , Idade Gestacional , Imageamento por Ressonância Magnética/métodos , Ultrassonografia Pré-Natal
2.
Ultrasound Obstet Gynecol ; 62(3): 405-413, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37099530

RESUMO

OBJECTIVE: To provide quantitative magnetic resonance imaging (MRI) super-resolution-based three-dimensional volumetric reference data on the growth dynamics of the ganglionic eminence (GE) relative to cortical and total fetal brain volumes (TBV). METHODS: This was a retrospective study of fetuses without structural central nervous system anomalies or other confounding comorbidities that were referred for fetal MRI. Super-resolution reconstructions of 1.5- and 3-Tesla T2-weighted images were generated. Semiautomatic segmentation of TBV and cortical volume and manual segmentation of the GE were performed. Cortical volume, TBV and GE volume were quantified and three-dimensional reconstructions were generated to visualize the developmental dynamics of the GE. RESULTS: Overall, 120 fetuses that underwent 127 MRI scans at a mean gestational age of 27.23 ± 4.81 weeks (range, 20-37 weeks) were included. In the investigated gestational-age range, GE volume ranged from 74.88 to 808.75 mm3 and was at its maximum at 21 gestational weeks, followed by a linear decrease (R2 = 0.559) throughout the late second and third trimesters. A pronounced reduction in GE volume relative to cortical volume and TBV occurred in the late second trimester, with a decline in this reduction observed in the third trimester (R2 = 0.936 and 0.924, respectively). Three-dimensional rendering allowed visualization of a continuous change in the shape and size of the GE throughout the second and third trimesters. CONCLUSIONS: Even small compartments of the fetal brain, which are not easily accessible by standardized two-dimensional modalities, can be assessed precisely by super-resolution processed fetal MRI. The inverse growth dynamics of GE volume compared with TBV and cortical volume reflects the transitory nature and physiological involution of this (patho-)physiologically important brain structure. The normal development and involution of the GE is mandatory for normal cortical development. Pathological changes of this transient organ precede impairment of cortical structures, and their detection may allow an earlier diagnosis of such anomalies. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Gravidez , Feminino , Humanos , Lactente , Estudos Retrospectivos , Encéfalo/anormalidades , Imageamento por Ressonância Magnética/métodos , Feto , Cuidado Pré-Natal , Idade Gestacional
3.
Ultrasound Obstet Gynecol ; 58(1): 34-41, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32484578

RESUMO

OBJECTIVES: Corpus callosal agenesis (CCA) is one of the most common brain malformations and is generally associated with a good outcome when isolated. However, up to 25% of patients are at risk of neurodevelopmental delay, which currently available clinical and imaging parameters are inadequate to predict. The objectives of this study were to apply and validate a fetal magnetic resonance imaging (MRI) anatomical scoring system in a cohort of fetuses with isolated CCA and to evaluate the correlation with postnatal neurodevelopmental outcome. METHODS: This was a retrospective cohort study of cases of prenatally diagnosed isolated CCA (as determined on ultrasound and MRI), with normal karyotype and with known postnatal neurodevelopmental outcome assessed by standardized testing. A fetal brain MRI anatomical scoring system based on seven categories (gyration, opercularization, temporal lobe symmetry, lamination, hippocampal position, basal ganglia and ventricular size) was developed and applied to the cohort; a total score of 0-11 points could be given, with a score of 0 representing normal anatomy. Images were scored independently by two neuroradiologists blinded to the outcome. For the purpose of assessing the correlation between fetal MRI score and neurodevelopmental outcome, neurodevelopmental test results were scored as follows: 0, 'below average' (poor outcome); 1, 'average'; and 2, 'above average' (good outcome). Spearman's rank coefficient was used to assess correlation, and inter-rater agreement in the assessment of fetal MRI score was calculated. RESULTS: Twenty-one children (nine females (42.9%)) fulfilled the inclusion criteria. Thirty-seven fetal MRI examinations were evaluated. Mean gestational age was 28.3 ± 4.7 weeks (range, 20-38 weeks). All fetuses were delivered after 35 weeks' gestation with no perinatal complications. Fetal MRI scores ranged from 0 to 6 points, with a median of 3 points. Inter-rater agreement in fetal MRI score assessment was excellent (intraclass correlation coefficient, 0.959 (95% CI, 0.921-0.979)). Neurodevelopmental evaluation was performed on average at 2.6 ± 1.46 years (range, 0.5-5.8 years). There was a significant negative correlation between fetal MRI score and neurodevelopmental outcome score in the three areas tested: cognitive (ρ = -0.559, P < 0.0001); motor (ρ = -0.414, P = 0.012) and language (ρ = -0.565, P < 0.0001) skills. Using fetal MRI score cut-offs of ≤ 3 (good outcome) and ≥ 4 points (high risk for poor outcome), the correct prognosis could be determined in 20/21 (95.2% (95% CI, 77.3-99.2%)) cases. CONCLUSION: By assessing structural features of the fetal brain on MRI, it may be possible to better stratify prenatally the risk of poor neurodevelopmental outcome in CCA patients. © 2020 Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Agenesia do Corpo Caloso/diagnóstico por imagem , Feto/diagnóstico por imagem , Imageamento por Ressonância Magnética/estatística & dados numéricos , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Agenesia do Corpo Caloso/complicações , Agenesia do Corpo Caloso/embriologia , Encéfalo/diagnóstico por imagem , Encéfalo/embriologia , Pré-Escolar , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/embriologia , Corpo Caloso/fisiopatologia , Feminino , Feto/embriologia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Masculino , Transtornos do Neurodesenvolvimento/etiologia , Valor Preditivo dos Testes , Gravidez , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Estatísticas não Paramétricas , Ultrassonografia Pré-Natal
4.
Ultrasound Obstet Gynecol ; 58(6): 837-845, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34097330

RESUMO

OBJECTIVE: Heterotaxy or isomerism of the atrial appendages is a congenital disorder with variable presentation, associated with both cardiac and non-cardiac anomalies, which may have a serious impact on fetal outcome. The aim of this exploratory study was to assess the value of fetal magnetic resonance imaging (MRI), as a complementary tool to ultrasound, for describing the morphological spectrum encountered in heterotaxy. METHODS: This retrospective study included 27 fetuses that underwent fetal MRI following prenatal suspicion of heterotaxy on ultrasound from 1998 to 2019 in a tertiary referral center. Heterotaxy was classified as left atrial isomerism (LAI) or right atrial isomerism (RAI) based on fetal echocardiography (FE) examination. In addition to routine prenatal ultrasound, fetal MRI was offered routinely to enhance the diagnosis of non-cardiac anomalies, which might have been missed on ultrasound. Prenatal findings on ultrasound, FE and MRI were reviewed systematically and compared with those of postnatal imaging and autopsy reports. RESULTS: Twenty-seven fetuses with heterotaxy and cardiovascular pathology, of which 19 (70%) had LAI and eight (30%) had RAI, were included. Seven (7/19 (37%)) fetuses with LAI had normal intracardiac anatomy, whereas all fetuses with RAI had a cardiac malformation. All 27 fetuses had non-cardiac anomalies on fetal MRI, including situs and splenic anomalies. In 12/19 (63%) fetuses with LAI, a specific abnormal configuration of the liver was observed on MRI. In three fetuses, fetal MRI revealed signs of total anomalous pulmonary venous connection obstruction. An abnormal bronchial tree pattern was suspected on prenatal MRI in 6/19 (32%) fetuses with LAI and 3/8 (38%) fetuses with RAI. CONCLUSIONS: Visualization on MRI of non-cardiac anomalies in fetuses with suspected heterotaxy is feasible and can assist the complex diagnosis of this condition, despite its limitations. This modality potentially enables differentiation of less severe cases from more complex ones, which may have a poorer prognosis. Fetal MRI can assist in prenatal counseling and planning postnatal management. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Feto/diagnóstico por imagem , Síndrome de Heterotaxia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Imagem Multimodal/métodos , Diagnóstico Pré-Natal/métodos , Adulto , Ecocardiografia/métodos , Estudos de Viabilidade , Feminino , Feto/anormalidades , Síndrome de Heterotaxia/embriologia , Humanos , Fenótipo , Gravidez , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos
5.
Ultrasound Obstet Gynecol ; 58(2): 254-263, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32730667

RESUMO

OBJECTIVES: To characterize spatiotemporal growth differences of prenatal brainstem substructures and cerebellum, using linear biometry and planimetry on fetal magnetic resonance imaging (MRI). METHODS: In this retrospective study, we included fetuses with normal brain and a precise midsagittal T2-weighted brain MRI sequence obtained between May 2003 and April 2019. The cross-sectional area, rostrocaudal diameter and anteroposterior diameter of the midbrain, pons (basis pontis and pontine tegmentum), medulla oblongata and cerebellar vermis, as well as the transverse cerebellar diameter, were quantified by a single observer. The diameters were also assessed by a second observer to test inter-rater variability. RESULTS: We included 161 fetuses with normal brain and a precise midsagittal MRI sequence, examined at a mean ± SD gestational age of 25.7 ± 5.4 (range, 14 + 0 to 39 + 2) weeks. All substructures of the fetal brainstem and the cerebellum could be measured consistently (mean ± SD interobserver intraclass correlation coefficient, 0.933 ± 0.065). We provide reference data for diameters and areas of the brainstem and cerebellum in the second and third trimesters. There was a significant quadratic relationship between vermian area and gestational age, and all other measured parameters showed a significant linear growth pattern within the observed period (P < 0.001). A significant change in the relative proportions of the brainstem substructures occurred between the beginning of the second trimester and the end of the third trimester, with an increase in the area of the pons (P < 0.001) and a decrease in that of the midbrain (P < 0.001), relative to the total brainstem area. CONCLUSIONS: The substructures of the fetal brainstem follow a distinct spatiotemporal growth pattern, characterized by a relative increase in the pons and decrease in the midbrain, between 15 and 40 weeks of gestation. Caution is needed when interpreting fetal brainstem appearance during the early second trimester, as the brainstem proportions differ significantly from the adult morphology. The reference data provided herein should help to increase diagnostic accuracy in detecting disorders of defective hindbrain segmentation. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Tronco Encefálico/diagnóstico por imagem , Feto/diagnóstico por imagem , Diagnóstico Pré-Natal , Tronco Encefálico/crescimento & desenvolvimento , Feminino , Idade Gestacional , Humanos , Imageamento por Ressonância Magnética , Gravidez , Valores de Referência , Estudos Retrospectivos
6.
Ultrasound Obstet Gynecol ; 56(1): 78-85, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31595598

RESUMO

OBJECTIVE: Normal cognitive development usually requires a structurally intact and complete cerebellar vermis. The aim of this study was to evaluate whether quantification by fetal magnetic resonance imaging (MRI) of vermis- and brainstem-specific imaging markers improves the definition of cystic posterior fossa malformations (cPFM). METHODS: Fetuses diagnosed with cPFM that had an available midsagittal plane on T2-weighted MRI were identified retrospectively and compared with gestational-age (GA) matched brain-normal controls. Fetuses with cPFM were assigned to three groups, according to standard criteria (vermian size and brainstem-vermis (BV) angle): normal vermian area and BV angle < 25° (Group 1); reduced vermian area and/or BV angle of 25-45° (Group 2); and reduced vermian area and BV angle > 45° (Group 3; Dandy-Walker malformation (DWM) group). The number of differentiable vermian lobules and the areas of the vermis, mesencephalon, pons and medulla oblongata were quantified, correlated with and controlled for GA, and compared between the study groups. RESULTS: In total, 142 cases of cPFM were included, with a mean GA of 25.20 ± 5.11 weeks. Cases comprised Blake's pouch cyst (n = 46), arachnoid cyst (n = 12), inferior vermian hypoplasia (n = 5), megacisterna magna (n = 35) and classic DWM (n = 44). In the control group, 148 fetuses were included, with a mean GA of 25.26 ± 4.12 weeks. All quantified areas and the number of differentiable vermian lobules had a significant positive correlation with GA. The number of vermian lobules and the areas of all quantified regions, except for that of the medulla oblongata, differed significantly between the study groups (P ≤ 0.015 for all). The control group had the highest number of differentiable vermian lobules and the DWM group had the lowest (P < 0.01). CONCLUSIONS: Prenatal MRI assessment of vermian lobules is a useful addition to standard neuroradiological and neurosonographic techniques. The quantification of vermian lobules using fetal MRI allows further differentiation of cPFM into subgroups and thereby improves the classification of hindbrain malformations. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Síndrome de Dandy-Walker/diagnóstico por imagem , Malformações do Sistema Nervoso/diagnóstico por imagem , Adulto , Fossa Craniana Posterior/anormalidades , Fossa Craniana Posterior/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes , Gravidez , Diagnóstico Pré-Natal
7.
Ultrasound Obstet Gynecol ; 53(6): 816-826, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30985045

RESUMO

OBJECTIVE: To assess the clinical feasibility and validity of fetal magnetic resonance imaging (MRI)-based three-dimensional (3D) reconstruction to locate, classify and quantify diaphragmatic defects in congenital diaphragmatic hernia (CDH). METHODS: This retrospective study included 46 cases of CDH which underwent a total of 69 fetal MRI scans (65 in-vivo and four postmortem) at the Medical University of Vienna during the period 1 January 2002 to 1 January 2017. Scans were performed between 16 and 38 gestational weeks using steady-state free precession, T2-weighted and T1-weighted sequences. MRI data were retrieved from the hospital database and manual segmentation of the diaphragm was performed with the open-source software, ITK-SNAP. The resulting 3D models of the fetal diaphragm and its defect(s) were validated by postmortem MRI segmentation and/or comparison of 3D model-based classification of the defect with a reference classification based on autopsy and/or surgery reports. Surface areas of the intact diaphragm and of the defect were measured and used to calculate defect-diaphragmatic ratios (DDR). The need for prosthetic patch repair and, in cases with repeated in-vivo fetal MRI scans, diaphragm growth dynamics, were analyzed based on DDR. RESULTS: Fetal MRI-based manual segmentation of the diaphragm in CDH was feasible for all 65 (100%) of the in-vivo fetal MRI scans. Based on the 3D diaphragmatic models, one bilateral and 45 unilateral defects (n = 47) were further classified as posterolateral (23/47, 48.9%), lateral (7/47, 14.9%) or hemidiaphragmatic (17/47, 36.2%) defects, and none (0%) was classified as anterolateral. This classification of defect location was correct in all 37 (100%) of the cases in which this information could be verified. Nineteen cases had a follow-up fetal MRI scan; in five (26.3%) of these, the initial CDH classification was altered by the results of the second scan. Thirty-three fetuses underwent postnatal diaphragmatic surgical repair; 20 fetuses (all of those with DDR ≥ 54 and 88% of those with DDR > 30) received a diaphragmatic patch, while the other 13 underwent primary surgical repair. Individual DDRs at initial and at follow-up in-vivo fetal MRI correlated significantly (P < 0.001). CONCLUSIONS: MRI-based 3D reconstruction of the fetal diaphragm in CDH has been validated to visualize, locate, classify and quantify the defect. Planning of postnatal surgery may be optimized by MRI-based prediction of the necessity for patch placement and the ability to personalize patch design based on 3D-printable templates. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Feminino , Hérnias Diafragmáticas Congênitas/cirurgia , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Retrospectivos
8.
Ultrasound Obstet Gynecol ; 52(5): 623-630, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28782259

RESUMO

OBJECTIVES: To optimize the imaging assessment of fetal hindbrain malformations, this observational magnetic resonance imaging (MRI) study aimed to assess whether fetal vermian lobulation can be quantified accurately and whether the relative growth of vermian lobules is uniform. METHODS: This retrospective study included singleton fetuses which underwent T2-weighted MRI in vivo with a 1.5-Tesla (T) scanner or within 24 h postmortem with a 3-T scanner between January 2007 and November 2016 at the Medical University of Vienna. We included only those showing normal structural brain development on ultrasound and MRI and which had image quality appropriate for quantitative analysis, i.e. good image quality and a precise midsagittal slice. Fetal brains were segmented and, for all discernible vermian lobules, we determined the mean relative area contribution (MRAC, the proportion of the lobule relative to the total vermian area, in terms of number of voxels). Inter- and intrarater measurement variability of a representative selection (21 cases) was determined by intraclass correlation coefficient (ICC) for voxel-based differences. A linear regression model was used to assess the correlation between the relative size of each vermian lobule (i.e. MRAC) and gestational age. RESULTS: A total of 78 fetuses scanned in vivo aged 18-32 gestational weeks and seven fetuses scanned postmortem aged 16-30 weeks had a precise midsagittal slice and image quality sufficient for quantitative analysis. After 22 weeks of gestation, seven of the nine known vermian lobules could be discriminated reliably. The MRAC showed a mean ± SD difference of only 2.89 ± 3.01% between in-vivo and postmortem measurements. The ICC of voxel-based interrater differences was mean ± SD, 0.91 ± 0.05 and the intrarater ICC was 0.95 ± 0.03. Growth of cerebellar lobules was non-uniform: the MRAC of culmen and DFT (declive + folium + tuber) increased with gestational age, whereas that of lingula, centralis, pyramis and nodulus decreased. The growth of the uvula showed no significant correlation with gestational age. CONCLUSIONS: Fetal vermian lobulation can be assessed accurately and reliably after 22 weeks on precise midsagittal sequences with 1.5-T T2-weighted MRI. Fetal vermian lobules show non-uniform growth, with expansion of DFT and culmen at the expense of the other vermian lobules. Evaluation and elucidation of vermian lobulation in normal fetuses should enable better characterization of fetuses with hindbrain malformations. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Vermis Cerebelar/anormalidades , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Autopsia , Vermis Cerebelar/diagnóstico por imagem , Vermis Cerebelar/embriologia , Feminino , Idade Gestacional , Humanos , Valor Preditivo dos Testes , Gravidez
11.
Radiologe ; 56(4): 375-86; quiz 387-8, 2016 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-27025384

RESUMO

The occipitocervical junction comprises of the occiput condyles, the atlas, and the axis. The radiological evaluation of this region is supported by craniometric measurement methods which are based on predefined anatomical landmarks. The main pathologies of the occipitocervical junction are traumatic injuries, congenital anomalies or normal variants, infections, arthropathies, and tumors. In this article, the anatomy of the occipitocervical junction as well as the most important craniometric measurement methods are explained. Moreover various pathologies and similar appearing normal variants are presented.


Assuntos
Articulação Atlantoaxial/diagnóstico por imagem , Articulação Atlantoaxial/lesões , Articulação Atlantoccipital/diagnóstico por imagem , Articulação Atlantoccipital/lesões , Malformações do Sistema Nervoso/diagnóstico por imagem , Doenças da Coluna Vertebral/diagnóstico por imagem , Articulação Atlantoaxial/patologia , Articulação Atlantoccipital/patologia , Cefalometria/métodos , Diagnóstico Diferencial , Diagnóstico por Imagem/métodos , Humanos , Malformações do Sistema Nervoso/patologia , Doenças da Coluna Vertebral/patologia
12.
Eur Radiol ; 25(1): 106-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25194707

RESUMO

OBJECTIVES: To compare the contrast agent effect of a full dose and half the dose of gadobenate dimeglumine in brain tumours at 7 Tesla (7 T) MR versus 3 Tesla (3T). METHODS: Ten patients with primary brain tumours or metastases were examined. Signal intensities were assessed in the lesion and normal brain. Tumour-to-brain contrast and lesion enhancement were calculated. Additionally, two independent readers subjectively graded the image quality and artefacts. RESULTS: The enhanced mean tumour-to-brain contrast and lesion enhancement were significantly higher at 7 T than at 3T for both half the dose (91.8 ± 45.8 vs. 43.9 ± 25.3 [p = 0.010], 128.1 ± 53.7 vs. 75.5 ± 32.4 [p = 0.004]) and the full dose (129.2 ± 50.9 vs. 66.6 ± 33.1 [p = 0.002], 165.4 ± 54.2 vs. 102.6 ± 45.4 [p = 0.004]). Differences between dosages at each field strength were also significant. Lesion enhancement was higher with half the dose at 7 T than with the full dose at 3T (p = .037), while the tumour-to-brain contrast was not significantly different. Subjectively, contrast enhancement, visibility, and lesion delineation were better at 7 T and with the full dose. All parameters were rated as good, at the least. CONCLUSION: Half the routine contrast agent dose at 7 T provided higher lesion enhancement than the full dose at 3T which indicates the possibility of dose reduction at 7 T. KEY POINTS: • The contrast effect of gadobenate dimeglumine was assessed at 7 T and 3T. • In brain tumours, contrast effect was higher at 7 T than at 3T. • Tumour-to-brain contrast at 7 T half dose and 3T full dose were comparable. • 7 T half dose lesion enhancement was higher than 3T full dose enhancement. • Our results indicate the possibility of contrast agent dose reduction at 7 T.


Assuntos
Neoplasias Encefálicas/patologia , Adulto , Idoso , Artefatos , Meios de Contraste/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Meglumina/administração & dosagem , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos/administração & dosagem , Estudos Prospectivos
13.
Ultrasound Obstet Gynecol ; 45(5): 618-21, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24913039

RESUMO

Tuberous sclerosis complex (TSC) is a genetic disorder characterized by abnormal cell proliferation and tumor growth in a number of organ systems, primarily the brain, kidneys, eyes and heart. Clinical symptoms vary according to the location of the tumor. The most common disorders are seizures, neurodevelopmental disorders, renal failure and arrhythmias. TSC was found to be influenced by inhibitors of the protein kinase mammalian target of rapamycin (mTOR), which regulates abnormal cellular proliferation. mTOR inhibitors have been studied effectively in patients with subependymal giant-cell astrocytomas and renal angiolipomas in the context of TSC. We describe a prenatally diagnosed case of giant rhabdomyoma, due to right ventricular outflow tract obstruction, which presented as a duct-dependent lesion. Postnatal treatment with the mTOR inhibitor everolimus initiated significant regression of the cardiac tumor. This finding suggests that mTOR inhibitor therapy is an option for giant rhabdomyomas that develop in the neonatal period.


Assuntos
Antineoplásicos/administração & dosagem , Ecocardiografia Doppler , Everolimo/administração & dosagem , Neoplasias Cardíacas/patologia , Rabdomioma/patologia , Esclerose Tuberosa/patologia , Adulto , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Neoplasias Cardíacas/tratamento farmacológico , Neoplasias Cardíacas/embriologia , Humanos , Recém-Nascido , Uso Off-Label , Gravidez , Diagnóstico Pré-Natal , Rabdomioma/tratamento farmacológico , Rabdomioma/embriologia , Resultado do Tratamento , Esclerose Tuberosa/tratamento farmacológico , Esclerose Tuberosa/embriologia , Carga Tumoral/efeitos dos fármacos
15.
Nervenarzt ; 85(10): 1298-303, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-25148869

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) are characterized by recurrent optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM) as well as the serological detection of antibodies to aquaporin-4 (AQP4-ab). However, longitudinal extensive spinal cord lesions are not pathognomonic for NMOSD as they can also occur in systemic autoimmune diseases or mimic spinal cord tumors. OBJECTIVES/METHODS: We report a female patient who initially presented with a subacute spinal syndrome and a longitudinal spinal cord lesion on magnetic resonance imaging (MRI). As the brain MRI showed only unspecific white matter lesions and the cerebrospinal fluid was normal, a spinal cord biopsy was performed to exclude malignancies and revealed inflammatory demyelinating changes. In addition, after several deep vein thromboses and the detection of antiphospholipid antibodies, an antiphospholipid syndrome (APS) was diagnosed. Many years after the spinal cord biopsy, AQP4-ab were tested and found to be positive. We discuss the important differential diagnoses of LETM, give an overview of previously reported NMOSD cases in which a spinal cord biopsy was performed and highlight the crucial role of AQP4-ab testing for the differential diagnosis of longitudinal spinal cord lesions. RESULTS/CONCLUSIONS: Considering possible serious sequelae of spinal biopsy procedures, testing for AQP4-ab is mandatory in patients with unclear longitudinally extensive spinal cord lesions and should be performed preoperatively in all cases. In light of the heterogeneity of available assays, different detection methods should be used in doubtful cases. The relationship between NMO and APS needs further clarification; however, AQP4 IgG testing is recommended in patients presenting with APS and myelitis, optic neuritis or brainstem encephalitis.


Assuntos
Mielite Transversa/patologia , Neuromielite Óptica/patologia , Neurite Óptica/patologia , Medula Espinal/patologia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Radiologe ; 53(2): 123-9, 2013 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-23354851

RESUMO

CLINICAL/METHODICAL ISSUE: Diagnosis and differential diagnosis of fetal thoracic and abdominal malformations. STANDARD RADIOLOGICAL METHODS: Ultrasound and magnetic resonance imaging (MRI). METHODICAL INNOVATIONS: In cases of suspected pathologies based on fetal ultrasound MRI can be used for more detailed examinations and can be of assistance in the differential diagnostic process. PERFORMANCE: Improved imaging of anatomical structures and of the composition of different tissues by the use of different MRI sequences. ACHIEVEMENTS: Fetal MRI has become a part of clinical routine in thoracic and abdominal malformations and is the basis for scientific research in this field. PRACTICAL RECOMMENDATIONS: In cases of thoracic or abdominal malformations fetal MRI provides important information additional to ultrasound to improve diagnostic accuracy, prognostic evaluation and surgical planning.


Assuntos
Abdome/anormalidades , Abdome/patologia , Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal/métodos , Tórax/anormalidades , Tórax/patologia , Abdome/embriologia , Humanos , Tórax/embriologia
18.
Radiologe ; 53(2): 109-15, 2013 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-23340683

RESUMO

CLINICAL/METHODICAL ISSUE: Evaluation and confirmation of fetal pathologies previously suspected or diagnosed with ultrasound. STANDARD RADIOLOGICAL METHODS: Ultrasound and magnetic resonance imaging (MRI). METHODICAL INNOVATIONS: Technique for prenatal fetal examination. PERFORMANCE: Fetal MRI is an established supplementary technique to prenatal ultrasound. ACHIEVEMENTS: Fetal MRI should only be used as an additional method in prenatal diagnostics and not for routine screening. PRACTICAL RECOMMENDATIONS: Fetal MRI should only be performed in perinatal medicine centers after a previous level III ultrasound examination.


Assuntos
Anormalidades Congênitas/embriologia , Anormalidades Congênitas/patologia , Doenças Fetais/patologia , Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal/métodos , Humanos
19.
Radiologe ; 53(2): 136-40, 2013 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-23371433

RESUMO

CLINICAL/METHODICAL ISSUE: Evaluation of the normal and pathological fetal brain. STANDARD RADIOLOGICAL METHODS: Magnetic resonance imaging (MRI). METHODICAL INNOVATIONS: Advanced MRI of the fetal brain. PERFORMANCE: Diffusion tensor imaging (DTI) is used in clinical practice, all other methods are used at a research level. ACHIEVEMENTS: Serving as standard methods in the future. PRACTICAL RECOMMENDATIONS: Combined structural and functional data for all gestational ages will allow more specific insight into the developmental processes of the fetal brain. This gain of information will help provide a common understanding of complex spatial and temporal procedures of early morphological features and their impact on cognitive and sensory abilities.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Encéfalo/embriologia , Imagem de Tensor de Difusão/métodos , Diagnóstico Pré-Natal/métodos , Humanos
20.
Ultrasound Obstet Gynecol ; 50(6): 805, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29205582
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