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PURPOSE: Although tumor localization and 3,4-dihydroxy-6-18F-fluoro-L-phenylalanine (FDOPA) uptake may have an association, preferential tumor localization in relation to FDOPA uptake is yet to be investigated in lower-grade gliomas (LGGs). This study aimed to identify differences in the frequency of tumor localization between FDOPA hypometabolic and hypermetabolic LGGs using a probabilistic radiographic atlas. METHODS: Fifty-one patients with newly diagnosed LGG (WHO grade II, 29; III, 22; isocitrate dehydrogenase wild-type, 21; mutant 1p19q non-codeleted,16; mutant codeleted, 14) who underwent FDOPA positron emission tomography (PET) were retrospectively selected. Semiautomated tumor segmentation on FLAIR was performed. Patients with LGGs were separated into two groups (FDOPA hypometabolic and hypermetabolic LGGs) according to the normalized maximum standardized uptake value of FDOPA PET (a threshold of the uptake in the striatum) within the segmented regions. Spatial normalization procedures to build a 3D MRI-based atlas using each segmented region were validated by an analysis of differential involvement statistical mapping. RESULTS: Superimposition of regions of interest showed a high number of hypometabolic LGGs localized in the frontal lobe, while a high number of hypermetabolic LGGs was localized in the insula, putamen, and temporal lobe. The statistical mapping revealed that hypometabolic LGGs occurred more frequently in the superior frontal gyrus (close to the supplementary motor area), while hypermetabolic LGGs occurred more frequently in the insula. CONCLUSION: Radiographic atlases revealed preferential frontal lobe localization for FDOPA hypometabolic LGGs, which may be associated with relatively early detection.
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Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Di-Hidroxifenilalanina , Glioma/diagnóstico por imagem , Humanos , Isocitrato Desidrogenase , Gradação de Tumores , Tomografia por Emissão de Pósitrons , Estudos RetrospectivosRESUMO
Vascular endothelial growth factor (VEGF) is involved in the development of major depressive disorder (MDD). Recently, a genome-wide association study has revealed that four VEGF-related single nucleotide polymorphisms (SNPs) (i.e., rs4416670, rs6921438, rs6993770 and rs10738760) were independently associated with circulating VEGF levels. The current study investigated the relationship between brain volume and these four SNPs in first-episode drug-naïve MDD patients. A total of 38 first-episode drug-naïve MDD patients and 39 healthy subjects (HS) were recruited and underwent high-resolution T1-weighted imaging. Blood samples were collected from all the participants for serum VEGF assays and VEGF-related SNPs genotyping. Genotype-diagnosis interactions related to whole-brain cortical thickness and hippocampal subfield volumes were evaluated for the four SNPs. The results revealed a genotype-diagnosis interaction only for rs6921438 (i.e., the MDD patients and HS with the G/G genotype versus the MDD patients and HS with A-carrier genotype) in the subiculum of the left hippocampus (p < 0.05), and not the other SNPs. There was a volume reduction in the left subiculum of G/G genotype patients compared with the other groups. The "hypochondriasis" scores of the HAMD-17 scale were significantly higher in the G/G genotype patients than the A-carrier genotype patients. The association was observed between VEGF-related SNP rs6921438 and subiculum atrophy in first-episode drug-naïve MDD patients.
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Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Córtex Cerebral/diagnóstico por imagem , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: Higher daytime cortisol levels because of a hyperactive hypothalamic-pituitary-adrenal axis have been reported in patients with major depressive disorder (MDD). The elevated glucocorticoids inhibit the proliferation of the oligodendrocytes that are responsible for myelinating the axons of white matter fibre tracts. AIMS: To evaluate the relationship between white matter integrity and serum cortisol levels during a first depressive episode in drug-naive patients with MDD (MDD group) using a tract-based spatial statistics (TBSS) method. METHOD: The MDD group (n = 29) and a healthy control group (n = 47) underwent diffusion tensor imaging (DTI) scans and an analysis was conducted using TBSS. Morning blood samples were obtained from both groups for cortisol measurement. RESULTS: Compared with the controls, the MDD group had significantly reduced fractional anisotropy values (P<0.05, family-wise error (FWE)-corrected) in the inferior fronto-occipital fasciculus, uncinate fasciculus and anterior thalamic radiation. The fractional anisotropy values of the inferior fronto-occipital fasciculus, uncinate fasciculus and anterior thalamic radiation had significantly negative correlations with the serum cortisol levels in the MDD group (P<0.05, FWE-corrected). CONCLUSIONS: Our findings indicate that the elevated cortisol levels in the MDD group may injure the white matter integrity in the frontal-subcortical and frontal-limbic circuits.
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Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/patologia , Imagem de Tensor de Difusão/métodos , Hidrocortisona/sangue , Substância Branca/patologia , Adulto , Idoso , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Substância Branca/diagnóstico por imagem , Adulto JovemRESUMO
OBJECTIVES: To evaluate whether quantitative susceptibility mapping (QSM) can be employed to detect abnormalities within normal-appearing basal ganglia on conventional MRI in patients with neuropsychiatric systemic lupus erythematosus (NPSLE). METHODS: For 33 SLE patients (13 NPSLE and 20 non-NPSLE patients) and 23 age/sex-matched controls, two radiologists independently measured the mean QSM and R2* values in various brain structures that appeared to be normal on conventional MR images. These values in each brain structure were compared among the two SLE groups and controls. RESULTS: Regarding the putamen, the NPSLE patients showed significantly higher QSM values than the non-NPSLE patients and controls (p < 0.05). For the lateral globus pallidus, both SLE groups showed significantly higher QSM values than the controls (p < 0.05). The R2* values were not significantly different between both SLE groups. The NPSLE patients showed a significant correlation between the mean QSM values in putamen and the disease duration (r = 0.63, p < 0.05). For the interobserver agreement, the QSM value was superior to the R2* value (0.690 vs. 0.446, Kendall W value). CONCLUSIONS: QSM can be used to identify increased susceptibility of the basal ganglia appearing to be normal on conventional MR images in NPSLE patients. KEY POINTS: ⢠QSM values in the putamen are significantly higher in NPSLE than non-NPSLE. ⢠NPSLE patients show correlation between QSM values in the putamen and disease duration. ⢠QSM is more sensitive than R2* mapping for detecting subtle changes.
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Gânglios da Base/patologia , Mapeamento Encefálico/métodos , Vasculite Associada ao Lúpus do Sistema Nervoso Central/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
OBJECTIVES: The aim of this study was to assess the susceptibility change in medial and lateral globus pallidus (GPm and GPl) related to age separately, using quantitative susceptibility mapping (QSM) and to determine whether QSM can depict GPm in Parkinson's disease (PD) patients. METHODS: QSM was performed in 19 PD patients and in 41 normal control (NC) subjects. First, we quantitatively analysed age-related changes in QSM value in NC for GPl and GPm by a manual region of interest (ROI) technique. Then, in PD patients and age-matched NC subjects, we evaluated the depiction of GPm on QSM images qualitatively. RESULTS: In NC, the QSM value within GPl significantly increased gradually with age (r = 0.32, p = 0.04), whereas it did not change with age in GPm. The average QSM value was significantly larger for GPl than for GPm (205 vs 191, p < 0.05). In both PD patients and age-matched NC, the depiction of GPm on QSM images was good in most cases (87 %, 33 of 38 sides in PD patients) mainly because of the differences in susceptibility between GPm and GPl. CONCLUSIONS: The QSM value in GPl increases gradually with age, which allows for the identification of GPm in elderly PD subjects.
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Mapeamento Encefálico/métodos , Globo Pálido/patologia , Doença de Parkinson/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos ProspectivosRESUMO
OBJECTIVE: In major depressive disorder (MDD) patients, higher morning cortisol levels due to a hyperactive hypothalamic-pituitary-adrenal (HPA) axis have been reported. The aim of the present study was to evaluate the relationship between cortical thinning and the serum cortisol levels during the first depressive episode in drug-naïve MDD patients using an automated surface-based morphometry (SBM) method. METHODS: The institutional review board approved this prospective study. MR imaging data were obtained using a 3T scanner by a three-dimensional fast-spoiled gradient recalled acquisition with steady state (3D-FSPGR). Thirty drug-naïve patients with MDD and 41 age- and gender-matched healthy subjects (controls) were enrolled. We then used the SBM method (Freesurfer) to generate cortical thickness maps, and measured the cortical thickness in each subject. Morning blood samples were drawn from all participants for cortisol measurements. RESULTS: We found the serum cortisol levels were significantly higher in the MDD patients than in the controls. The MDD patients manifested significant thinning of the left lateral orbitofrontal cortex compared with the controls. There was a significant negative linear correlation between the thickness of the left lateral orbitofrontal cortex and the serum cortisol levels in the MDD patients. CONCLUSIONS: In the early stage of MDD, the thickness of the lateral orbitofrontal cortex was significantly reduced, and also showed a significant inverse correlation with the serum cortisol levels. Since the lateral orbitofrontal cortex contains a high concentration of glucocorticoid receptor, glucocorticoid receptor-mediated signaling transductions could contribute to neurotoxicity, which might occur when there are high cortisol levels in patients with MDD.
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Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/patologia , Lobo Frontal/patologia , Hidrocortisona/sangue , Receptores de Glucocorticoides/metabolismo , Adulto , Estudos de Casos e Controles , Transtorno Depressivo Maior/metabolismo , Feminino , Lobo Frontal/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Imageamento Tridimensional , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Estudos Prospectivos , Transdução de Sinais , Adulto JovemRESUMO
BACKGROUND AND PURPOSE: Parkinson disease is a prevalent disease, with olfactory dysfunction recognized as an early nonmotor manifestation. It is sometimes difficult to differentiate Parkinson disease from atypical parkinsonism using conventional MR imaging and motor symptoms. It is also known that olfactory loss occurs to a lesser extent or is absent in atypical parkinsonism. To the best of our knowledge, no study has examined olfactory bulb changes to differentiate Parkinson disease from atypical parkinsonism, even in an early diagnosis, and its association with conventional MR imaging findings. Hence, we aimed to assess the utility of olfactory bulb measurements in differentiating Parkinson disease from atypical parkinsonism even in the early stage. MATERIALS AND METHODS: In this retrospective study, we enrolled 108 patients with Parkinson disease, 13 with corticobasal syndrome, 15 with multiple system atrophy, and 17 with progressive supranuclear palsy who developed parkinsonism. Thirty-nine age-matched healthy subjects served as controls. All subjects underwent conventional MR imaging and 3D FIESTA for olfactory bulb measurements using manual ROI quantification of the cross-sectional olfactory bulb area using the coronal plane. Bilateral olfactory bulb measurements were averaged. For group comparisons, we used the Welch t test, and we assessed diagnostic accuracy using receiver operating characteristic analysis. RESULTS: Patients with Parkinson disease had a mean olfactory bulb area of 4.2 (SD, 1.0 mm2), significantly smaller than in age-matched healthy subjects (6.6 [SD, 1.7 mm2], P < .001), and those with corticobasal syndrome (5.4 [SD, 1.2 mm2], P < .001), multiple system atrophy (6.5 [SD, 1.2 mm2], P < .001), and progressive supranuclear palsy (5.4 [SD, 1.2 mm2], P < .001). The receiver operating characteristic analysis for the olfactory bulb area measurements showed good diagnostic performance in differentiating Parkinson disease from atypical parkinsonism, with an area under the curve of 0.87, an optimal cutoff value of 5.1 mm2, and a false-positive rate of 18%. When we compared within 2 years of symptom onset, the olfactory bulb in Parkinson disease (4.2 [SD, 1.1 mm2]) remained significantly smaller than in atypical parkinsonism (versus corticobasal syndrome (6.1 [SD, 0.7 mm2]), P < .001; multiple system atrophy (6.3 [SD, 1.4 mm2]), P < .001; and progressive supranuclear palsy (5.2 [1.3 mm2], P = .003, respectively). CONCLUSIONS: 3D FIESTA-based olfactory bulb measurement holds promise for distinguishing Parkinson disease from atypical parkinsonism, especially in the early stage.
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Imageamento por Ressonância Magnética , Bulbo Olfatório , Doença de Parkinson , Transtornos Parkinsonianos , Humanos , Bulbo Olfatório/diagnóstico por imagem , Bulbo Olfatório/patologia , Masculino , Feminino , Doença de Parkinson/diagnóstico por imagem , Idoso , Diagnóstico Diferencial , Estudos Retrospectivos , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Transtornos Parkinsonianos/diagnóstico por imagem , Imageamento Tridimensional/métodos , Sensibilidade e Especificidade , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/diagnóstico por imagemRESUMO
Complex networks inside the hippocampus could provide new insights into hippocampal abnormalities in various psychiatric disorders and dementia. However, evaluating intra-networks in the hippocampus using MRI is challenging. Here, we employed a high spatial resolution of conventional structural imaging and independent component analysis to investigate intra-networks structural covariance in the hippocampus. We extracted the intra-networks based on the intrinsic connectivity of each 0.9â mm isotropic voxel to every other voxel using a data-driven approach. With a total volume of 3â cc, the hippocampus contains 4115 voxels for a 0.9â mm isotropic voxel size or 375 voxels for a 2â mm isotropic voxel of high-resolution functional or diffusion tensor imaging. Therefore, the novel method presented in the current study could evaluate the hippocampal intra-networks in detail. Furthermore, we investigated the abnormality of the intra-networks in major depressive disorders. A total of 77 patients with first-episode drug-naïve major depressive disorder and 79 healthy subjects were recruited. The independent component analysis extracted seven intra-networks from hippocampal structural images, which were divided into four bilateral networks and three networks along the longitudinal axis. A significant difference was observed in the bilateral hippocampal tail network between patients with major depressive disorder and healthy subjects. In the logistic regression analysis, two bilateral networks were significant predictors of major depressive disorder, with an accuracy of 78.1%. In conclusion, we present a novel method for evaluating intra-networks in the hippocampus. One advantage of this method is that a detailed network can be estimated using conventional structural imaging. In addition, we found novel bilateral networks in the hippocampus that were disturbed in patients with major depressive disorders, and these bilateral networks could predict major depressive disorders.
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PURPOSE: To develop a support vector machine (SVM) classifier using CT texture-based analysis in differentiating focal-type autoimmune pancreatitis (AIP) and pancreatic duct carcinoma (PD), and to assess the radiologists' diagnostic performance with or without SVM. MATERIALS AND METHODS: This retrospective study included 50 patients (20 patients with focal-type AIP and 30 patients with PD) who underwent dynamic contrast-enhanced CT. Sixty-two CT texture-based features were extracted from 2D images of the arterial and portal phase CTs. We conducted data compression and feature selections using principal component analysis (PCA) and produced the SVM classifier. Four readers participated in this observer performance study and the statistical significance of differences with and without the SVM was assessed by receiver operating characteristic (ROC) analysis. RESULTS: The SVM performance indicated a high performance in differentiating focal-type AIP and PD (AUC = 0.920). The AUC for all 4 readers increased significantly from 0.827 to 0.911 when using the SVM outputs (p = 0.010). The AUC for inexperienced readers increased significantly from 0.781 to 0.905 when using the SVM outputs (p = 0.310). The AUC for experienced readers increased from 0.875 to 0.912 when using the SVM outputs, however, there was no significant difference (p = 0.018). CONCLUSION: The use of SVM classifier using CT texture-based features improved the diagnostic performance for differentiating focal-type AIP and PD on CT.
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Pancreatite Autoimune , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Pancreatite Autoimune/diagnóstico por imagem , Estudos Retrospectivos , Diagnóstico Diferencial , Carcinoma Ductal Pancreático/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Aprendizado de Máquina , Ductos Pancreáticos , Radiologistas , Neoplasias PancreáticasRESUMO
Our purpose was to identify correlations between 18F-fluorodihydroxyphenylalanine (18F-FDOPA) uptake and physiologic MRI, including relative cerebral blood volume (rCBV) and apparent diffusion coefficient (ADC), in gliomas with different molecular subtypes and to evaluate their prognostic values. Methods: Sixty-eight treatment-naïve glioma patients who underwent 18F-FDOPA PET and physiologic MRI were retrospectively selected (36 with isocitrate dehydrogenase wild-type [IDHwt], 16 with mutant 1p/19q noncodeleted [IDHm-noncodel], and 16 with mutant codeleted [IDHm-codel]). Fluid-attenuated inversion recovery hyperintense areas were segmented and used as regions of interest. For voxelwise and patientwise analyses, Pearson correlation coefficients (rvoxelwise and rpatientwise) between the normalized SUV (nSUV), rCBV, and ADC were evaluated. Cox regression analysis was performed to investigate the associations between overall survival and rvoxelwise, maximum or median nSUV, median rCBV, or median ADC. Results: For IDHwt and IDHm-noncodel gliomas, nSUV demonstrated significant positive correlations with rCBV (rvoxelwise = 0.25 and 0.31, respectively; rpatientwise = 0.50 and 0.70, respectively) and negative correlations with ADC (rvoxelwise = -0.19 and -0.19, respectively; rpatientwise = -0.58 and -0.61, respectively) in both voxelwise and patientwise analyses. IDHm-codel gliomas demonstrated a significant positive correlation between nSUV and ADC only in voxelwise analysis (rvoxelwise = 0.18). In Cox regression analysis, rvoxelwise between nSUV and rCBV (hazard ratio, 28.82) or ADC (hazard ratio, 0.085) had significant associations with overall survival for only IDHwt gliomas. Conclusion: IDHm-codel gliomas showed distinctive patterns of correlations between amino acid PET and physiologic MRI. Stronger correlations between nSUV and rCBV or ADC may result in a worse prognosis for IDHwt gliomas.
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Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/fisiopatologia , Volume Sanguíneo Cerebral , Di-Hidroxifenilalanina/análogos & derivados , Glioma/diagnóstico por imagem , Glioma/fisiopatologia , Tomografia por Emissão de Pósitrons , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Difusão , Feminino , Glioma/patologia , Glioma/terapia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-IdadeRESUMO
There has been a growing interest in the abnormality of networks across the brain in major depressive disorder (MDD). We aimed to investigate the structural covariance networks in patients with first-episode and drug-naïve MDD using structural imaging. A total of 77 patients with first-episode and drug-naïve MDD and 79 healthy subjects (HS) were recruited, from whom high-resolution T1-weighted images were analysed. Incident component analysis was used to calculate the brain networks based on grey matter volume covariance. There were significant differences in salience network, medial temporal lobe network, default mode network and central executive network between MDD and HS (p < 0.05). Further, the disturbance of medial temporal lobe network was significantly correlated with the severity of depressive symptoms (p < 0.05). In conclusion, we found a novel abnormality in the brain network in the medial temporal lobe primarily involving the hippocampus and parahippocampal gyrus in patients with first-episode and treatment-naïve MDD.
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Transtorno Depressivo Maior/patologia , Imageamento por Ressonância Magnética , Rede Nervosa/patologia , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Mapeamento Encefálico , Estudos de Casos e Controles , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologiaRESUMO
BACKGROUND: Although structural correlation network (SCN) analysis is an approach to evaluate brain networks, the neurobiological interpretation of SCNs is still problematic. Brain-derived neurotrophic factor (BDNF) is well-established as a representative protein related to neuronal differentiation, maturation, and survival. Since a valine-to-methionine substitution at codon 66 of the BDNF gene (BDNF Val66Met single nucleotide polymorphism (SNP)) is well-known to have effects on brain structure and function, we hypothesized that SCNs are affected by the BDNF Val66Met SNP. To gain insight into SCN analysis, we investigated potential differences between BDNF valine (Val) homozygotes and methionine (Met) carriers in the organization of their SCNs derived from inter-regional cortical thickness correlations. METHODS: Forty-nine healthy adult subjects (mean age = 41.1 years old) were divided into two groups according to their genotype (n: Val homozygotes = 16, Met carriers = 33). We obtained regional cortical thickness from their brain T1 weighted images. Based on the inter-regional cortical thickness correlations, we generated SCNs and used graph theoretical measures to assess differences between the two groups in terms of network integration, segregation, and modularity. RESULTS: The average local efficiency, a measure of network segregation, of BDNF Met carriers' network was significantly higher than that of the Val homozygotes' (permutation p-value = 0.002). Average shortest path lengths (a measure of integration), average local clustering coefficient (another measure of network segregation), small-worldness (a balance between integration and segregation), and modularity (a representative measure for modular architecture) were not significantly different between group (permutation p-values ⧠0.01). DISCUSSION AND CONCLUSION: Our results suggest that the BDNF Val66Met polymorphism may potentially influence the pattern of brain regional morphometric (cortical thickness) correlations. Comparing networks derived from inter-regional cortical thickness correlations, Met carrier SCNs have denser connections with neighbors and are more distant from random networks than Val homozygote networks. Thus, it may be necessary to consider potential effects of BDNF gene mutations in SCN analyses. This is the first study to demonstrate a difference between Val homozygotes and Met carriers in brain SCNs.
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PURPOSE: To assess atrophy differences among brain regions and time-dependent changes after whole-brain radiation therapy (WBRT). MATERIALS AND METHODS: Twenty patients with lung cancer who underwent both WBRT and chemotherapy (WBRT group) and 18 patients with lung cancer who underwent only chemotherapy (control group) were recruited. Three-dimensional T1WI were analyzed to calculate volume reduction ratio after WBRT in various brain structures. The volume reduction ratio of the hippocampus was compared among following 3 periods: 0-3, 4-7, and 8-11 months after WBRT. RESULTS: The volume reduction ratio of the hippocampus was significantly higher in the WBRT group than in the control group (p < 0.05). In WBRT group, the volume reduction ratio of the hippocampus was significantly higher than that of the cortex and white matter (p < 0.05). There were significant differences in the volume reduction ratio between of 0-3 months and that of 4-7 months (p = 0.02) and between 4-7 months and that of 8-11 months (p = 0.01). CONCLUSION: The hippocampus is more vulnerable to the radiation compared with other brain regions and may become atrophic even in the early stage after WBRT.
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Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Irradiação Craniana/efeitos adversos , Hipocampo/patologia , Hipocampo/efeitos da radiação , Neoplasias Pulmonares/patologia , Idoso , Atrofia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/efeitos da radiação , Mapeamento Encefálico/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estudos RetrospectivosRESUMO
The authors wish to replace the Table 1.
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PURPOSE: The purpose of our study is to develop deep convolutional neural network (DCNN) for detecting hip fractures using CT and MRI as a gold standard, and to evaluate the diagnostic performance of 7 readers with and without DCNN. METHODS: The study population consisted of 327 patients who underwent pelvic CT or MRI and were diagnosed with proximal femoral fractures. All radiographs were manually checked and annotated by radiologists referring to CT and MRI for selecting ROI. At first, a DCNN with the GoogLeNet model was trained by 302 cases. The remaining 25 cases and 25 control subjects were used for the observer performance study and for the testing of DCNN. Seven readers took part in this study. A continuous rating scale was used to record each observer's confidence level. Subsequently, each observer interpreted with the DCNN outputs and rated them again. The area under the curve (AUC) was used to compare the fracture detection. RESULTS: The average AUC of the 7 readers was 0.832. The AUC of DCNN alone was 0.905. The average AUC of the 7 readers with DCNN outputs was 0.876. The AUC of readers with DCNN output were higher than those without(pâ¯<â¯0.05). The AUC of the 2 experienced readers with DCNN output exceeded the AUC of DCNN alone. CONCLUSION: For detecting the hip fractures on radiographs, DCNN developed using CT and MRI as a gold standard by radiologists improved the diagnostic performance including the experienced readers.
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Aprendizado Profundo , Fraturas do Quadril/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Pelve/diagnóstico por imagem , Curva ROC , Intensificação de Imagem Radiográfica/métodos , Radiografia Abdominal/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: This study aims to investigate hippocampal subfield volumes in patients with hippocampal sclerosis (HS) without visually detectable MRI abnormalities and to determine the diagnostic accuracy using hippocampal subfield volumes. MATERIALS AND METHODS: We examined 46 patients with unilateral HS who had a histopathological diagnosis, and 54 controls. The patients were divided into two groups; visually detectable HS (n = 26) and undetectable HS (n = 20) on MRI. The volumes of hippocampal subfield using FreeSurfer were compared among the three groups. Diagnostic accuracy was calculated as the AUC of ROC using cutoff values for each individual subfield. RESULTS: Compared with the controls, visually detectable HS showed significantly reduced volumes of all the hippocampal subfields and entire hippocampus, whereas visually undetectable HS showed significant atrophy only in the CA3 and hippocampus-amygdala-transition-area. To diagnose visually undetectable HS, the CA3 volumes had AUC of 0.719, which was higher than AUC of 0.614 based on the entire hippocampal volumes. CONCLUSION: Visually undetectable HS demonstrated volume reductions in the CA3. Further, the CA3 volumes was more useful to diagnose visually undetectable HS compared with the entire hippocampal volumes.
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Epilepsia do Lobo Temporal/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Atrofia/patologia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Feminino , Humanos , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes , Esclerose/patologiaRESUMO
PURPOSE: To evaluate the potential of full-iterative reconstruction (IR) for improving image quality of the cystic artery on CT angiography and to assess observer performance. METHODS: Thirty patients who underwent both liver dynamic CT and conventional angiography were included in this retrospective study. All CT data were reconstructed through filtered back projection (FBP), adaptive iterative dose reduction 3D (AIDR3D), and forward-projected, model-based, iterative reconstruction solution (FIRST), respectively. In objective study, we analyzed mean ΔCT numbers (the difference between the HU peak of the vessel and the background) and full-width at tenth-maximum (FWTM) of three parts of the cystic artery by profile curve method comparing the three reconstructions. Subjectively, visualization was evaluated using a four-point scale performed by two blinded observers. ANOVA was used for statistical analysis. RESULTS: In all parts of the cystic artery, the mean ΔCT number of FIRST was shown to be significantly better than that of FBP and AIDR3D (p < 0.05). FWTM in FIRST was the smallest in all of the vessels. The mean visualization score was significantly better with FIRST than with other CT reconstructions (p < 0.05). CONCLUSIONS: The FIRST algorithm led to improved CTA visualization of the cystic artery.
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Angiografia por Tomografia Computadorizada/métodos , Processamento de Imagem Assistida por Computador/métodos , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Artérias/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Estudos RetrospectivosRESUMO
BACKGROUND: A genome-wide association study using megadata identified 17 single-nucleotide polymorphisms (SNPs) in candidate genes for major depressive disorder (MDD). These MDD susceptibility polymorphisms may affect white matter (WM) integrity. This study aimed to investigate the relationship between WM alterations and 17 SNPs in candidate genes for MDD in the first depressive episode of drug-naive MDD patients using a tract-based spatial statistics (TBSS) method. METHODS: Thirty-five drug-naive MDD patients with a first depressive episode and 47 age-and sex-matched healthy subjects underwent diffusion tensor imaging scans and genotyping. The genotype-diagnosis interactions related to WM integrity were evaluated using TBSS for the 17 SNPs. RESULTS: For the anterior thalamic radiation, cingulum, corticospinal tract, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, superior longitudinal fasciculus, uncinate fasciculus, forceps major, and forceps minor, the genotype effect significantly differed between diagnosis groups (P<0.05, family-wise error corrected) in only one SNP, rs301806, in the arginine-glutamic acid dipeptide (RE) repeats (RERE) gene. CONCLUSION: The RERE polymorphism was associated with WM alterations in first-episode and drug-naive MDD patients, which may be at least partially related to the manifestation of MDD. Future studies are needed to explore the gene-environment interactions with regard to individual WM integrity.
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Purpose: Compared with healthy subjects (HS), patients with major depressive disorder (MDD) exhibit volume differences that affect the volume changes in several areas such as the limbic, cortical, subcortical, and white matter. Catechol-O-methyltransferase (COMT) is a methylation enzyme that catalyzes endogenous catecholamines. The Val158Met polymorphism of COMT has been reported to affect the dopamine (DA) levels, which plays an important role in psychiatric diseases. However, the relationships among both DA levels, COMT genotype, and brain morphology are complicated and controversial. In previous studies that investigated the hippocampal subfields, the greatest brain abnormalities in MDD patients were observed in Cornu Ammonis (CA)1 and the subiculum, followed by that in CA2-3. We have prospectively demonstrated the relationship between the single-nucleotide polymorphism of the Val158Met COMT gene (rs4680) and the hippocampal subfields in drug-naive MDD patients. Patients and methods: In this study, we compared 27 MDD patients and 42 HS who were divided into groups based on their COMT genotype. The effects of the diagnosis, genotype, and genotype-diagnosis interaction related to CA1 and the subiculum volumes, as well as the whole-brain cortical thickness, were evaluated by performing a FreeSurfer statistical analysis of high-resolution magnetic resonance imaging (MRI) findings. Results: The results revealed that there was a statistically significant interaction between the effects of diagnosis and genotype on the right subiculum (a component of the hippocampus). Conclusion: This Val158Met COMT polymorphism may influence the subiculum volume in drug-naive, first-episode MDD patients.
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OBJECTIVE: Recently, a genome-wide association study successfully identified genetic variants associated with major depressive disorder (MDD). The study identified 17 independent single-nucleotide polymorphisms (SNPs) significantly associated with diagnosis of MDD. These SNPs were predicted to be enriched in genes that are expressed in the central nervous system and function in transcriptional regulation associated with neurodevelopment. The study aimed to investigate associations between 17 SNPs and brain morphometry using magnetic resonance imaging (MRI) in drug-naïve patients with MDD and healthy controls (HCs). METHODS: Forty-seven patients with MDD and 42 HCs were included. All participants underwent T1-weighted structural MRI and genotyping. The genotype-diagnosis interactions associated with regional cortical thicknesses were evaluated using voxel-based morphometry for the 17 SNPs. RESULTS: Regarding rs301806, an SNP in the RERE genomic regions, we found a significant difference in a genotype effect in the right-lateral orbitofrontal and postcentral lobes between diagnosis groups. After testing every possible diagnostic comparison, the genotype-diagnosis interaction in these areas revealed that the cortical thickness reductions in the MDD group relative to those in the HC group were significantly larger in T/T individuals than in C-carrier ones. For the other SNPs, no brain area was noted where a genotype effect significantly differed between the two groups. CONCLUSIONS: We found that a RERE gene SNP was associated with cortical thickness reductions in the right-lateral orbitofrontal and postcentral lobes in drug-naïve patients with MDD. The effects of RERE gene polymorphism and gene-environment interactions may exist in brain structures of patients with MDD.