RESUMO
BACKGROUND: A significant number of patients with mild traumatic brain injury (mTBI) would experience cognitive deficit. PURPOSE: To investigate the brain structural changes in sub-acute mTBI by diffusion kurtosis imaging (DKI) and volumetric analysis, and to assess the relationship between brain structural changes and cognitive functions. MATERIAL AND METHODS: A total of 23 patients with sub-acute mTBI and 24 control participants were recruited. All the participants underwent examinations of neuropsychological tests, DKI, and magnetic resonance imaging (MRI)-based morphological scans. Images were investigated using whole brain-based analysis and further regions of interest-based analysis for subcortical nuclei. The neuropsychological tests were compared between the mTBI and the control group. Correlation analysis was performed to examine the relationship between gray matter (GM) volume, DKI parameters, and cognitive functions. RESULTS: Compared with control participants, mTBI patients performed worse in the domains of verbal memory, attention and executive function (P < 0.05). No regional GM volume differences were observed between the mTBI and control groups (P > 0.05). Using DKI, patients with mTBI showed lower mean kurtosis (MK) in widespread white matter (WM) regions and several subcortical nuclei (P < 0.05), and higher mean diffusivity (MD) in the right pallidum (P < 0.05). Lower MK value of multiple WM regions and several subcortical nuclei correlated with cognitive impairment (P < 0.05). CONCLUSION: DKI was sensitive in detecting brain microstructural changes in patients with sub-acute mTBI showing lower MK value in widespread WM regions and several subcortical nuclei, which were statistically associated with cognitive deficits.
Assuntos
Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Imagem de Tensor de Difusão/métodos , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricosRESUMO
Background Previous studies revealed that subcortical nuclei were harmed in the process of Alzheimer's disease (AD). Purpose To investigate the volumetric and diffusion kurtosis imaging (DKI) parameter changes of subcortical nuclei in AD and their relationship with cognitive function. Materials and Methods A total of 17 mild AD patients, 15 moderate to severe AD patients, and 16 controls underwent neuropsychological tests and magnetic resonance imaging (MRI) scans. Volume, mean kurtosis (MK), mean diffusivity (MD), and fractional anisotropy (FA) were measured in hippocampus, thalamus, caudate, putamen, pallidum, and amygdala. MRI parameters were compared. Correlation analysis was performed between subcortical nuclei volume, DKI parameters, and MMSE score. Results Significant volume reduction was seen in the left hippocampus in mild AD, and the bilateral hippocampus, thalamus, putamen, left caudate, and right amygdala in moderate to severe AD ( P < 0.05). Increased MD values were observed in the left hippocampus, left amygdala, and right caudate in mild AD, and the bilateral hippocampus and right amygdala in moderate to severe AD ( P < 0.05). Decreased MK values were observed only in the bilateral hippocampus in moderate to severe AD ( P < 0.05). No group significances were found in FA value. MMSE score was positively correlated with the volume of the bilateral hippocampus, thalamus, and putamen, and MK value of the left hippocampus ( P < 0.05). A negative correlation was found with the MD value of the bilateral hippocampus and left amygdala ( P < 0.05). Conclusion Mild AD mainly has microscopic subcortical changes revealed by increased MD value, and moderate to severe AD mainly has macroscopic subcortical changes revealed by volume reduction. MK is more sensitive in severe AD than mild AD.
Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Mapeamento Encefálico/métodos , Imagem de Tensor de Difusão/métodos , Imageamento por Ressonância Magnética/métodos , Idoso , Doença de Alzheimer/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Cognição , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Tamanho do ÓrgãoRESUMO
PURPOSE: This study aims to elucidate the frequency, nondetection rate, and clinical importance of incidental extracerebral findings (IECFs) on brain nonenhanced magnetic resonance imaging (MRI). METHODS: A total of 8284 brain MRIs performed between January 1, 2015 and December 31, 2015 were evaluated for the presence of IECFs and the distribution of IECFs was analyzed. IECFs were categorized as E1 (clinically unimportant, e.g., sinus mucosal thickening); E2 (likely unimportant, e.g., pharyngeal mucosal symmetrical thickening); and E3 (potentially important, e.g., pharyngeal mucosal asymmetrical thickening). The nondetection rate was determined by comparing the results of the structured approach with the initial MRI reports. The medical records were examined for patients with E3 IECFs to assess clinical importance and outcome of these lesions. RESULTS: A total of 5992 IECFs were found in 4469 of the 8284 patients (54.0%). E1 findings constituted 82.2% (4924/5992) of all IECFs; E2 constituted 16.6% (995/5992) and E3 constituted 1.2% (73/5992). Overall IECFs and E1 findings were significantly more common in male patients (P < 0.05). Statistically significant difference was also seen between the different age groups (P < 0.001). The nondetection rate was 56.9% (3409/5992) for overall IECFs and 32.9% (24/73) for E3 IECFs. Of the 73 patients with E3 IECFs, 34 (46.6%) received final diagnosis and appropriate treatment during the study period. CONCLUSIONS: IECFs are prevalent in clinical patients on brain MR images with a nondetection rate of 32.9% for potentially important (E3) findings. The reporting of IECFs according to clinical importance is helpful for patients' management.
Assuntos
Encefalopatias/diagnóstico por imagem , Achados Incidentais , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: To investigate the value of contrast-enhanced MRI in differentiation between benign nasopharyngeal lymphoid hyperplasia (NPLH) and T1 stage nasopharyngeal carcinoma (NPC). METHODS: Eighty-six NPLH patients and 38 T1 stage NPC patients who underwent a contrast-enhanced MRI and an endoscopic biopsy were included. The patients' symptoms and MRI features of nasopharyngeal mucosal thickening like location, symmetry, nasopharyngeal bubble, superficial mucus, nasopharyngeal retention cysts, serrated protrusions, contrast-enhancement type were documented. Accompanying signs such as sinus mucosal thickening, middle ear effusion, and cervical lymph nodes enlargement were also recorded. These MRI features were compared by Chi-square tests. Logistic regression analysis was done to identify the most predictive MRI features of malignancy. RESULTS: NPLH patients had more symptoms of pharynx discomfort or pain, while T1 stage NPC patients had more symptom of neck mass (P < 0.05). The most common pattern of nasopharyngeal mucosal thickening in NPLH was diffuse wall thickening (38.37%), while unilateral posterolateral wall thickening (39.47%) was more in T1 stage NPC. Nasopharyngeal bubble, retention cysts, serrated protrusions, symmetry, homogeneous enhancement, slight enhancement and vertical stripes were more common in NPLH, while nasopharyngeal wall asymmetry, inhomogeneous enhancement, moderated or marked enhancement and cervical lymph nodes enlargement were more in T1 stage NPC (P < 0.05). Logistic regression analysis identified unilateral posterolateral wall thickening, nasopharyngeal wall asymmetry, inhomogeneous enhancement and cervical lymph nodes enlargement were the most predictive MRI features for malignancy. CONCLUSIONS: Careful analysis of contrast-enhanced MRI features of the nasopharynx and neck is helpful in differentiating benign NPLH from T1 stage NPC.
Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias Nasofaríngeas/diagnóstico , Pseudolinfoma/diagnóstico , Biópsia , Meios de Contraste , Diagnóstico Diferencial , Endoscopia , Feminino , Humanos , Hiperplasia , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Pseudolinfoma/patologiaRESUMO
BACKGROUND: Intravenous administration of recombinant tissue plasminogen activator (rtPA) is approved treatment for acute ischemic stroke <3 h of symptom onset. PURPOSE: To determine the impact of the timing and degree of recanalization on clinical outcome after rtPA infusion in patients. MATERIAL AND METHODS: Seventy-five patients with ischemic stroke in the middle cerebral artery territory treated with intravenous rtPA within 3 h were studied consecutively. Magnetic resonance imaging (MRI), including magnetic resonance angiography (MRA), before, 6 h, and 24 h after thrombolytic therapy was undertaken. Depending on the MRA results acquired 6 h after rtPA infusion, recanalization was graded as: early recanalization (ER), delayed recanalization (DR), and no recanalization (NR). Clinical outcome was assessed using the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS). RESULTS: Of patients in the ER, DR and NR groups, 71.4% (15/21), 13.3% (2/15), and 30.7% (12/39), respectively, showed dramatic improvement in NIHSS score 7 days after rtPA administration compared with those scores upon hospital admission. The 6-h and 24-h NIHSS scores and 3-month mRS scores of ER patients were significantly lower than those of the other two groups (P < 0.05). The 24-h, 7-d NHISS and mRS scores of DR patients were significantly higher than NR patients (P = 0.001, 0.002, 0.049, respectively). Three patients in the DR group died during follow-up. CONCLUSION: These data suggest that DR is associated with clinical deterioration. Patients treated with rtPA thrombolysis should be under close observation for 6-24 h. Corresponding treatment should be considered once DR appears.
Assuntos
Fibrinolíticos/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Angiografia por Ressonância Magnética/métodos , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
To use DCE-magnetic resonance imaging (MRI) and diffusion-weighted imaging to evaluate the hyperbaric oxygen efficacy (HBO) in experimental traumatic brain injury (TBI). Forty-two rabbits were randomly divided into four groups: TBI, TBI + HBO, sham group, sham + HBO. The TBI + HBO and sham + HBO received a total of 10 HBO treatments within 7 days following TBI, and MRI was performed within a month after TBI. Functional assessments were performed pre-TBI, and at 1 and 30 days. In focal lesion area, K(trans) in TBI + HBO group was lower than TBI group at both acute and subacute phase (p < 0.05). ADC was higher in TBI + HBO group than TBI group at acute phase (p < 0.01), but lower at subacute phase (p < 0.05). In perifocal area, K(trans) were lower in TBI + HBO group than TBI group at acute phase (p < 0.01) after TBI. ADC was lower in the TBI + HBO group than in the TBI group at both acute and subacute phase (p < 0.01).The VCS was higher in TBI + HBO group than TBI group at 30 days (p < 0.05). HBO could improve the impaired BBB and cytotoxic edema after TBI and promote the recovery of neurofunction.
Assuntos
Lesões Encefálicas/patologia , Lesões Encefálicas/terapia , Encéfalo/patologia , Oxigenoterapia Hiperbárica , Imageamento por Ressonância Magnética , Doença Aguda , Animais , Lesões Encefálicas/diagnóstico , Imagem de Difusão por Ressonância Magnética , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Exame Neurológico , Coelhos , Distribuição Aleatória , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do TratamentoRESUMO
The aim of this study was to explore the relationship between abnormality on susceptibility-weighted imaging (SWI) and newly-developed depression after mild traumatic brain injury. The study registered 200 patients with closed TBI and normal finding at CT and conventional MRI. All patients underwent MRI including conventional MR sequences and SWI. The number and volume of microbleed lesions were semi-automatically outlined and manually counted. All patients were followed up with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-IV) within 1 year after TBI. The difference in microbleed lesions on SWI was compared between the depressive and non-depressive groups. The depressive group had a higher rate of abnormality on SWI than did the non-depressive group (p < 0.001). Among patients that had exhibited microbleed lesions, the number and volume of lesions were greater in the depressive group than the non-depressive group (both p < 0.001). These differences in numbers and volume of lesions were found only at the frontal, parietal and temporal lobes (all p < 0.001). Among patients that had exhibited microbleed lesions, the number and volume of lesions in other areas were not significantly different between the depressive and non-depressive groups (all p > 0.05). In conclusion, SWI was useful to identify the microbleed lesions after mild TBI. The distribution range and location of microbleed lesions were correlated with depression after TBI.
Assuntos
Lesões Encefálicas/complicações , Lesões Encefálicas/patologia , Transtorno Depressivo/etiologia , Transtorno Depressivo/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Feminino , Hemorragia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The reported prevalence of unruptured cerebral aneurysms (UCAs) varies widely. OBJECTIVE: To measure the prevalence of UCAs by using 3-dimensional time-of-flight magnetic resonance angiography in adults aged 35 to 75 years. DESIGN: Cross-sectional study done between June 2007 and June 2011. SETTING: Two communities chosen at random from 2 districts (1 urban and 1 suburban) in Shanghai, China. PARTICIPANTS: 4813 adults aged 35 to 75 years. MEASUREMENTS: Three-dimensional time-of-flight magnetic resonance angiography, interpreted by 3 observers blinded to the participants' information, was used to identify the location and size of UCAs and to estimate the overall, age-specific, and sex-specific prevalence. RESULTS: 369 UCAs were found in 336 participants (130 men and 206 women); 4477 participants had no evidence of UCAs. The prevalence was 7.0% overall (95% CI, 6.3% to 7.7%), with 5.5% for men (CI, 4.6% to 6.4%) and 8.4% for women (CI, 7.3% to 9.5%). The overall prevalence of UCAs was higher in women than in men (P < 0.001) and peaked at ages 55 to 64 years in men and women. The UCAs were mostly located in the internal carotid artery (81%), and 90.2% had a maximum diameter less than 5 mm. Mean diameter was larger in women than in men (3.7 mm vs. 3.2 mm; P < 0.009). LIMITATION: Participants were from 2 communities selected from 2 districts in Shanghai, and adults older than 75 years were not studied. CONCLUSION: The overall prevalence of UCAs was 7.0% in Chinese adults aged 35 to 75 years, and most lesions had a diameter less than 5 mm. PRIMARY FUNDING SOURCE: National Natural Science Foundation of China.
Assuntos
Aneurisma Intracraniano/epidemiologia , Adulto , Distribuição por Idade , Idoso , Artéria Carótida Interna/patologia , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Aneurisma Intracraniano/patologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por SexoRESUMO
Introduction: Patients undergoing maintenance hemodialysis are vulnerable to coronavirus disease 2019 (COVID-19), exhibiting a high risk of hospitalization and mortality. Thus, early identification and intervention are important to prevent disease progression in these patients. Methods: This was a two-center retrospective observational study of patients on hemodialysis diagnosed with COVID-19 at the Lingang and Xuhui campuses of Shanghai Sixth People's Hospital. Patients were randomized into the training (130) and validation cohorts (54), while 59 additional patients served as an independent external validation cohort. Artificial intelligence-based parameters of chest computed tomography (CT) were quantified, and a nomogram for patient outcomes at 14 and 28 days was created by screening quantitative CT measures, clinical data, and laboratory examination items, using univariate and multivariate Cox regression models. Results: The median dialysis duration was 48 (interquartile range, 24-96) months. Age, diabetes mellitus, serum phosphorus level, lymphocyte count, and chest CT score were identified as independent prognostic indicators and included in the nomogram. The concordance index values were 0.865, 0.914, and 0.885 in the training, internal validation, and external validation cohorts, respectively. Calibration plots showed good agreement between the expected and actual outcomes. Conclusion: This is the first study in which a reliable nomogram was developed to predict short-term outcomes and survival probabilities in patients with COVID-19 on hemodialysis. This model may be helpful to clinicians in treating COVID-19, managing serum phosphorus, and adjusting the dialysis strategies for these vulnerable patients to prevent disease progression in the context of COVID-19 and continuous emergence of novel viruses.
RESUMO
AIM: To quantify iron deposition in Alzheimer's disease (AD), amnestic mild cognitive impairment (aMCI), and control individuals using susceptibility weighted imaging (SWI). MATERIALS AND METHODS: Sixty participants (22 aMCI, 20 AD, 18 normal controls) underwent conventional magnetic resonance imaging (MRI) and SWI using axial/oblique coronal sequences. Phase images were used to calculate bilateral iron deposition in 18 regions of interest (ROI). The radian angle value was calculated and compared between the three participant groups. RESULTS: The difference in radian angle value was significant between the aMCI and control groups in the left (L)-hippocampus, L-head of the caudate nucleus, R-lenticular nucleus, L-lenticular nucleus (P =0.02239, <0. 001, 0.03571, 0.00943, respectively). The difference in radian angle value was significant between the AD and aMCI groups in the R-cerebellar hemisphere, L-cerebellar hemisphere, R-hippocampus, L-hippocampus, R-red nucleus, R-thalamus, L-thalamus, and splenium of corpus callosum (P =0.02754, 0.01839, 0.00934, 0.04316, 0.02472, 0.00152, <0.001, 0.01448, respectively). Pearson correlation coefficients of the Mini-Mental State Examination score were all significant for the bilateral cerebellar hemisphere, hippocampus, red nucleus, lenticular nucleus, thalamus, R-head of the caudate nucleus, and splenium of corpus callosum. CONCLUSION: Iron deposition in the hippocampus, head of the caudate nucleuslenticular nucleus, and thalamus are significantly different between individuals with aMCI, AD, and controls. The thalamus is a particularly sensitive area. Using SWI to quantify the iron deposition is a useful tool in detecting aMCI and AD.
Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Hipocampo , Humanos , Ferro , Imageamento por Ressonância MagnéticaRESUMO
OBJECTIVES: To enhance diagnosis of gastrointestinal neuroendocrine carcinomas using CT and contrast-enhanced CT images. METHODS: A total of 44 patients with gastrointestinal neuroendocrine carcinomas, as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University Shanghai China, were included in the study. CT and enhanced CT scanning were performed, and the resulting images were reviewed and analyzed. RESULTS: Twenty-seven males and 17 females were enrolled. Gastrointestinal involvement included the following: 5 cases located in the middle or inferior segment of the esophagus; 5 in the gastric cardia, 15 in the body of stomach, 6 located in the gastric antrum; 5 located in the Vater papilla of the duodenum; and 8 located in the colon. Among the 44 cases 80%-90% of the lesions had homogeneous density. Totally 81.8% (36/44) cases demonstrated homogeneous enhancement in arterial phases, most of the cases (n = 33) moderately or obviously enhanced. Only 17.2% (8/44) cases appeared as heterogeneous enhancement. And 86.4% cases (n = 38) were further enhanced in the venous phase. The CT images also revealed some of the metastases. Some liver metastasis cases have obvious homogeneous enhancement. CONCLUSIONS: CT and enhanced CT provide useful information regarding gastrointestinal neuroendocrine carcinomas' location, density, enhancement pattern, and some metastasis. These features are helpful to increase the diagnostic accuracy.
Assuntos
Carcinoma Neuroendócrino/diagnóstico por imagem , Neoplasias Gastrointestinais/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Imuno-Histoquímica , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
OBJECTIVE: To investigate the characteristics and associations of MRI-visible perivascular spaces (PVS) with clinical progression and longitudinal cognitive decline across the Alzheimer's disease spectrum. METHODS: We included 1429 participants (641 [44.86%] female) from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. PVS number and grade in the centrum semiovale (CSO-PVS), basal ganglia (BG-PVS), and hippocampus (HP-PVS) were compared among the control (CN), mild cognitive impairment (MCI), and Alzheimer's disease (AD) groups. PVS were tested as predictors of diagnostic progression (i.e., CN to MCI/AD or MCI to AD) and longitudinal changes in the 13-item Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog 13), Mini-Mental State Examination (MMSE), memory (ADNI-MEM), and executive function (ADNI-EF) using multiple linear regression, linear mixed-effects, and Cox proportional hazards modeling. RESULTS: Compared with CN subjects, MCI and AD subjects had more CSO-PVS, both in number (p < 0.001) and grade (p < 0.001). However, there was no significant difference in BG-PVS and HP-PVS across the AD spectrum (p > 0.05). Individuals with moderate and frequent/severe CSO-PVS had a higher diagnostic conversion risk than individuals with no/mild CSO-PVS (log-rank p < 0.001 for all) in the combined CN and MCI group. Further Cox regression analyses revealed that moderate and frequent/severe CSO-PVS were associated with a higher risk of diagnostic conversion (HR = 2.007, 95% CI = 1.382-2.914, p < 0.001; HR = 2.676, 95% CI = 1.830-3.911, p < 0.001, respectively). A higher CSO-PVS number was associated with baseline cognitive performance and longitudinal cognitive decline in all cognitive tests (p < 0.05 for all). CONCLUSIONS: CSO-PVS were more common in MCI and AD and were associated with cognitive decline across the AD spectrum.
Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Feminino , Humanos , Masculino , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Testes Neuropsicológicos , Imageamento por Ressonância Magnética , Testes de Estado Mental e DemênciaRESUMO
OBJECTIVE: The aim of this study was to evaluate the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and its quantitative coefficient (K(trans)) in the assessment of the extent of traumatic brain injury (TBI) in a rabbit model. METHODS: A weight-drop device (height, 20 cm) was used with varying impact force, 30-, 60-, or 90-g weight, to induce mild, moderate, or severe TBI, respectively. DCE-MRI and T2-weighted MRI was used to examine the injured groups and a sham group 1 day after TBI. We analyzed the relationship between K(trans) and the lesion volume on the basis of T2-weighted images in each group. RESULTS: The lesion volumes in both the severe and the moderate injury groups were greater than those observed in the mild injury group (p < 0.01). Furthermore, the lesion volumes in the severe injury group tended to be greater than those seen in the moderate injury group (p = 0.053). The K(trans) values in all injury groups were greater than those observed in the sham group (p < 0.01). In addition, the K(trans) values in the severe and moderate injury groups were greater than those of the mild injury group (p < 0.01), and the values seen in the severe injury group tended to be greater than those of the moderate injury group (p = 0.08). Moreover, we observed a correlation between the K(trans) value and lesion volume in all injury groups (mild injury group: r = 0.766, p = 0.01; moderate injury group: r = 0.731, p = 0.04; and severe injury group: r = 0.886, p = 0.019). CONCLUSIONS: DCE-MRI and its quantitative coefficient, K(trans), have the potential to accurately assess the blood-brain barrier and the extent of injury in an in vivo model of TBI.
Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Lesões Encefálicas/diagnóstico , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Animais , Barreira Hematoencefálica/patologia , Lesões Encefálicas/mortalidade , Meios de Contraste , Modelos Animais de Doenças , Escala de Gravidade do Ferimento , Coelhos , Intensificação de Imagem Radiográfica/métodos , Distribuição Aleatória , Sensibilidade e Especificidade , Estatísticas não ParamétricasRESUMO
AIM: To compare diffusion tensor image (DTI) study in association fiber tracts among normal control (NC), amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) subjects. To assess diagnostic value of DTI in aMCI and differential diagnosis of DTI study between aMCI and AD. MATERIAL AND METHODS: DTI was used to assess changes in cerebral association fiber tracts in NC, aMCI, and AD subjects (n = 20/group). Regions of interest included the inferior fronto-occipital fascicles (IFOF), superior longitudinal fascicles and cingulum tract, genu of corpus callosum (Gcc) was set right, splenium of corpus callosum was set left. Bilateral fractional anisotropy (FA) and apparent diffusion coefficient values were compared in three groups. RESULTS: Relative to NC, aMCI subjects had significantly different FA values for the IFOF and cingulum tract, while AD subjects had significantly different FA values of IFOF, Gcc, and cingulum tract. Relative to aMCI, AD subjects had significantly different FA values of cingulum tract. CONCLUSION: Based on the results, DTI could be used as a diagnostic method for aMCI with abnormal changes in IFOF and cingulum tract. DTI could also be used for differential diagnosis of aMCI and AD by comparing FA values of the cingulum tract. Abnormal FA values of IFOF, Gcc, and cingulum tract in AD patients may help to elucidate the pathological processes in this disease.
Assuntos
Doença de Alzheimer/patologia , Amnésia/patologia , Encéfalo/patologia , Transtornos Cognitivos/patologia , Fibras Nervosas Mielinizadas/patologia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Anisotropia , Mapeamento Encefálico , Imagem de Tensor de Difusão , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To analyze the value of readout-segmented echo-planar imaging (rs-EPI) with parallel imaging and a two-dimensional (2D) navigator-based reacquisition technique in the detection of brain lesions at the skull base. MATERIALS AND METHODS: A total of 54 patients (male 37, female 17) with suspected skull-base intracranial lesions underwent magnetic resonance imaging (MRI), including pre-T1 weighted imaging, T2-weighted imaging, Fluid Attenuated Inversion Recovery (FLAIR), standard single shot echo-planar imaging diffusion weighted imaging (ss-EPI DWI) and rs-EPI DWI, post-contrast T1-weighted. The total number of lesions and the number of lesions at different sites on all MRI sequences were used as reference measures. Then differences in detecting lesions and image quality between standard ss-EPI DWI and rs-EPI DWI were analyzed. RESULTS: There was a significant difference in the total number of lesions detected by rs-EPI DWI and standard ss-EPI DWI (P = 0.01). But this difference was mainly due to an improved ability of rs-EPI DWI to detect lesions located in the anterior cranial fossa, compared to ss-EPI DWI (P=0.02); the ability of ss-EPI and rs-EPI DWI to detect lesions in the middle cranial fossa and posterior cranial fossa was not significantly different (P = 0.471, P = 0.486, respectively). For image quality, rs-EPI images were significantly better than standard ss-EPI DWI images (P<0.001). CONCLUSION: The rs-EPI DWI technique is a useful tool for the detection and evaluation of lesions located at the skull base.
Assuntos
Lesões Encefálicas/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar , Interpretação de Imagem Assistida por Computador/métodos , Base do Crânio/patologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Estudos Retrospectivos , Base do Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodosRESUMO
Background and Purpose: To determine the feasibility of time-resolved angiography with stochastic trajectories (TWIST) in the diagnosis of spinal dural arteriovenous fistula (SDAVF) and perimedullary arteriovenous fistula (PAVF). Methods: A total of 11 negative patients with TWIST examination were retrospective analyzed and then 18 patients with suspected spinal vascular diseases underwent TWIST. For negative patients, Adamkiewicz artery (AKA), great anterior radiculomedullary vein (GARV) and anterior spinal artery (ASA) were retrospective analyzed. In patients, the results of TWIST were compared with those of DSA. Results: The displaying rates of the ASA, AKA and GARV in 11 negative patients were 100, 90.9, and 90.9%, respectively. The AKA and GARV were separated on TWIST. Of 18 patients, 11 and three were diagnosed with SDAVF and PAVF, respectively. The spinal cord vascular malformation diagnosed on TWIST was consistent with DSA with an excellent intermodality agreement (Kappa = 0.92, p < 0.001). The feeding artery and side of all 11 SDAVF patients were displayed on TWIST and the results were consistent with DSA. For PAVF patients, the feeding artery in two patients and the sides as displayed on TWIST were consistent with DSA. Conclusions: TWIST enables the differentiation of the spinal artery and vein and the differential diagnosis of SDAVF and PAVF.
RESUMO
The relationship between magnetic resonance imaging (MRI)-visible enlarged perivascular spaces (EPVS) and Aß and tau deposition is poorly investigated in cognitively normal older population. In our study, a total of 106 cognitively normal older subjects from the Alzheimer's Disease Neuroimaging Initiative database were included. All the subjects underwent brain MRI, florbetapir positron emission tomography (PET), and flortaucipir PET examinations. EPVS were rated on MRI using a 5-point scale in the basal ganglia (BG-EPVS) and the centrum semiovale (CSO-EPVS). Our study revealed that 43 subjects had high-degree BG-EPVS (degree >1) and 58 subjects had high-degree CSO-EPVS (degree >1). In logistic regression, high degree of BG-EPVS was associated with age (odds ratio [OR]: 1.08, 95% confidence interval [CI]: 1.01-1.16) and severe deep white matter hyperintensity (OR: 2.67, 95% CI: 1.12-6.35). High degree of CSO-EPVS was associated with flortaucipir PET positivity (OR: 2.24, 95% CI: 1.02-4.93). In conclusion, high degree of CSO-EPVS was associated with tau deposition in the brain, whereas high degree of BG-EPVS was associated with age and severe deep white matter hyperintensity, a marker of small vessel disease.
Assuntos
Envelhecimento/metabolismo , Envelhecimento/patologia , Peptídeos beta-Amiloides/metabolismo , Sistema Glinfático/diagnóstico por imagem , Sistema Glinfático/metabolismo , Voluntários Saudáveis , Proteínas tau/metabolismo , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina , Carbolinas , Etilenoglicóis , Feminino , Sistema Glinfático/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Compostos RadiofarmacêuticosRESUMO
Background and Purpose: An association between artery tortuosity and neuroimaging of cerebral small vessel disease (SVD) has been reported, especially in the posterior circulation. However, few studies involved the whole magnetic resonance imaging (MRI) spectrum of SVD in association with anterior circulation arterial tortuosity. This study aimed to investigate the relationship between internal carotid artery (ICA) tortuosity and the neuroimaging of SVD. Methods: Data of 1,264 consecutive patients in whom cerebral vessel diseases were suspected and who underwent both MRI and computed tomography angiography were reviewed from a prospective registry. Internal carotid artery tortuosity was evaluated using the tortuosity index (TI), which was defined as the ratio of the vessel centerline length divided by the straight length. Magnetic resonance imaging was used to assess cerebral microbleeds (CMBs), white matter hyperintensities (WMHs), enlarged perivascular spaces (EPVSs), and lacunes. Results: The TIs of the ICA for patients with and without SVD MRI markers were 1.81 ± 0.42 and 1.72 ± 0.33, respectively (P < 0.001). Univariate analysis showed that the ICA TI were positively correlated with each SVD MRI marker (P < 0.001), and the correlation coefficients (r s ) were 0.57, 0.42, 0.30, and 0.26 for EPVSs, WMHs, CMBs, and lacunes, respectively. The adjusted ORs of the ICA TI were 1.52 (95% CI 1.44-1.60, P < 0.001) for EPVS grade 1, 2.05 (95% CI 1.93-2.18, P < 0.001) for EPVS grades 2-4, and 1.09 (95% CI 1.03-1.15, P = 0.004) for WMH grade 3. Conclusions: The TI of ICA was higher in patients with neuroimaging of SVD. Internal carotid arteries tortuosity was associated with MRI-defined markers of SVD, including EPVS and high-grade WMH, and positively correlated with EPVS severity. Arterial tortuosity might be a risk factor for SVD. This finding may have potential clinical significance for identifying patients with suspected SVD.
RESUMO
Objectives: To explore structural variations of the circle of Willis using three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA), and to compare this modality with digital subtraction angiography (DSA). Methods: A total of 819 consecutive patients suspected of having cerebral vascular diseases underwent 3D-TOF-MRA, followed by DSA within 2 weeks. We report accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 3D-TOF-MRA compared with DSA. Results: The sensitivity and specificity of combined analyses were 90-100 and 98-100%, respectively. The sensitivity and NPV of 3D-TOF-MRA images for A-, C-, D-, and H-types of circle of Willis anomalies were 100%. The specificity, accuracy and sensitivity were all 100% for detecting absence of the anterior communicating artery (ACOA). Sensitivity, specificity, PPV, and NPV were all 100% for detecting F-type. The sensitivity and PPV of volume rendered (VR) images for the B-, E-, and G-types were relatively low (85.0, 86.2, and 73.8%, respectively). Maximum intensity projection (MIP) was somewhat better (88.3, 89.2, and 81.8%, respectively). Combined analyses were better still (95.8, 96.1, and 99.0%, respectively). Specificity and NPVs were high (99.3-100%). Conclusions: 3D-TOF-MRA compares well to DSA for evaluation of the structure of the circle of Willis. As 3D-TOF-MRA is a non-invasive modality, it may be preferred as a means to evaluate structural variations of the circle of Willis.