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BACKGROUND: Neuroblastoma varies widely in risk. Risk indicators in infants with incidental neuroblastoma refine treatment confidence for observation or intervention. The potential of functional imaging, particularly PET/CT, remains to be defined. PROCEDURE: A retrospective review of infants under 18 months diagnosed with incidental neuroblastoma from 2008 to May 2022 in our institute was conducted. Before October 2015, incidental patients were treated similarly to symptomatic cases, undergoing biopsy or surgical excision upon diagnosis (early cohort). Post October 2015 (late cohort), treatment decisions were guided by PET/CT findings, with 18F-DOPA PET/CT confirming diagnosis and staging. For tumors with low 18F-FDG uptake, an expectant observation approach was considered. Patient characteristics, diagnostic methods, image findings at diagnosis, treatment courses, and responses were compared between cohorts. RESULTS: Thirty infants less than 18 months were identified with incidental neuroblastoma and completed PET/CT at diagnosis. The early and late cohorts each comprised 15 patients. In the late cohort, nine out of 15 patients (60%) presented with localized FDG non-avid tumors were offered the option of expectant observation. Of these, seven patients opted for observation, thereby avoiding surgery. Treatment outcomes were comparable between early and late cohorts, except for one mortality of a patient who, despite showing 18F-FDG activity, declined treatment. CONCLUSIONS: This study demonstrates the potential utility of 18F-DOPA and 18F-FDG PET/CT scans in aiding clinical decision-making for infants with localized, incidental neuroblastoma. Given the concerns regarding radiation exposure, such imaging may be valuable for cases with suspected metastasis, initial large tumor size, or growth during follow-up.
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Di-Hidroxifenilalanina , Fluordesoxiglucose F18 , Neuroblastoma , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Neuroblastoma/diagnóstico por imagem , Neuroblastoma/terapia , Neuroblastoma/patologia , Lactente , Masculino , Feminino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos , Di-Hidroxifenilalanina/análogos & derivados , Recém-Nascido , Achados Incidentais , Estudos de Viabilidade , Seguimentos , Tomada de Decisão Clínica , PrognósticoRESUMO
OBJECTIVES: Exosomes are membrane vesicles that are actively secreted in response to microenvironmental stimuli. In this study, we quantified the amount of exosomes in patients with significant coronary artery disease (CAD) and evaluated its relationship with myocardial perfusion imaging (MPI) results. METHODS: Patients who underwent both MPI and coronary angiography were recruited. Plasma was collected during angiography, and exosomes were extracted via the precipitation method. The summed stress scores (SSS), summed difference scores, and ventricular functional parameters were calculated from the MPI and compared with the amounts of exosomes and extracted miRNAs. RESULTS: In total, 115 patients were enrolled (males: 78 %; mean age: 66.6 ± 10.6 years). Those with abnormal SSS according to the MPI had significantly fewer exosomes (p = 0.032). After multivariate analysis, the SSS remained significantly related to the amount of exosomes (p = 0.035). In forty randomly selected samples, miRNA-432-5p and miRNA-382-3p were upregulated in patients with abnormal SSS. CONCLUSIONS: Patients with compromised poststress myocardial perfusion on MPI tended to have fewer exosomes in association with CAD-related miRNAs. This is the first study to clarify the fundamental and pathophysiological causes of CAD using radiographic examinations.
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BACKGROUND: Cerebral venous outflow alterations contribute to central nervous system pathology in aging and neurodegenerative disorders and are potentially linked to underlying cerebral microangiopathy. We investigated whether cerebral venous reflux (CVR) is more closely associated with cerebral amyloid angiopathy (CAA) than hypertensive microangiopathy in intracerebral hemorrhage (ICH) survivors. METHODS: This cross-sectional study included 122 patients of spontaneous ICH with magnetic resonance and positron emission tomography imaging studies (2014-2022) in Taiwan. The presence of CVR was defined as abnormal signal intensity in the dural venous sinus or internal jugular vein on magnetic resonance angiography. Cerebral amyloid load was measured using the Pittsburgh compound B standardized uptake value ratio. Clinical and imaging characteristics associated with CVR were evaluated in univariable and multivariable analyses. In the subset of patients with CAA, we applied univariable and multivariable linear regression analyses to evaluate the association between CVR and cerebral amyloid retention. RESULTS: Compared with patients without CVR (n=84, 64.5±12.1 years), patients with CVR (n=38, 69.4±11.5 years) were significantly more likely to have CAA-ICH (53.7% versus 19.8%; P<0.001) and had a higher cerebral amyloid load (standardized uptake value ratio [interquartile range], 1.28 [1.12-1.60] versus 1.06 [1.00-1.14]; P<0.001). In a multivariable model, CVR was independently associated with CAA-ICH (odds ratio, 4.81 [95% CI, 1.74-13.27]; P=0.002) after adjustment for age, sex and conventional small vessel disease markers. In CAA-ICH, higher PiB retention was observed in patients with CVR than patients without CVR (standardized uptake value ratio [interquartile range], 1.34 [1.08-1.56] versus 1.09 [1.01-1.26]; P<0.001). In multivariable analysis after adjustment for potential confounders, the presence of CVR was independently associated with a higher amyloid load (standardized ß=0.40; P=0.001). CONCLUSIONS: In spontaneous ICH, CVR is associated with CAA and a higher amyloid burden. Our results suggest venous drainage dysfunction potentially plays a role in CAA and cerebral amyloid deposition.
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Angiopatia Amiloide Cerebral , Humanos , Estudos Transversais , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Angiopatia Amiloide Cerebral/complicações , Imageamento por Ressonância Magnética , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/complicações , Tomografia por Emissão de PósitronsRESUMO
Background: Head and neck lymphedema (HNL), including external and internal types, could be a possible consequence for patients who have received neck dissection and radiotherapy for head and neck cancer. Initially, the common presentations are heaviness or tightness, followed by swelling in appearance, or difficulty speaking and swallowing in internal edema cases. Lymphovenous anastomosis (LVA) is an established approach to treat extremity lymphedema. We hereby present our preliminary experience in using LVA to treat HNL. Methods: Between March 2021 and January 2024, six patients with HNL were treated with LVA via a preauricular or submandibular incision of the obstructed side. Lymphedema Symptom Intensity and Distress Surveys-Head and Neck (LSIDS-H&N) were used for evaluation. In addition, for the external type, MD Anderson Cancer Center Head and Neck Lymphedema (MDACC HNL) rating scale was used for evaluation. For the internal type, Swallowing Quality of Life was used for evaluation. Results: With an average follow-up period of 15.4â ±â 15.9 months, LSIDS-H&N improved from 1.11â ±â 0.54 to 0.44â ±â 0.66 (P = 0.02). For patients with the external type, within an average follow-up period of 15â ±â 16.1 months, the MDACC HNL rating scale improved from level 2 to 0 or 1a (P = 0.008). For patients with the internal type, within an average follow-up period of 21â ±â 17.3 months, Swallowing Quality of Life improved from 130.5â ±â 9.2 to 151â ±â 19.8 (P = 0.5). Conclusions: Based on our preliminary results, LVA could be a potential solution to both external and internal HNL.
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Tau, a hallmark of Alzheimer's disease, is poorly characterized in cerebral amyloid angiopathy. We aimed to assess the clinico-radiological correlations between tau positron emission tomography scans and cerebral amyloid angiopathy. We assessed cerebral amyloid and hyperphosphorylated tau in patients with probable cerebral amyloid angiopathy (n = 31) and hypertensive small vessel disease (n = 27) using 11C-Pittsburgh compound B and 18F-T807 positron emission tomography. Multivariable regression models were employed to assess radio-clinical features related to cerebral tau pathology in cerebral amyloid angiopathy. Cerebral amyloid angiopathy exhibited a higher cerebral tau burden in the inferior temporal lobe [1.25 (1.17-1.42) versus 1.08 (1.05-1.22), P < 0.001] and all Braak stage regions of interest (P < 0.05) than hypertensive small vessel disease, although the differences were attenuated after age adjustment. Cerebral tau pathology was significantly associated with cerebral amyloid angiopathy-related vascular markers, including cortical superficial siderosis (ß = 0.12, 95% confidence interval 0.04-0.21) and cerebral amyloid angiopathy score (ß = 0.12, 95% confidence interval 0.03-0.21) after adjustment for age, ApoE4 status and whole cortex amyloid load. Tau pathology correlated significantly with cognitive score (Spearman's ρ=-0.56, P = 0.001) and hippocampal volume (-0.49, P = 0.007), even after adjustment. In conclusion, tau pathology is more frequent in sporadic cerebral amyloid angiopathy than in hypertensive small vessel disease. Cerebral amyloid angiopathy-related vascular pathologies, especially cortical superficial siderosis, are potential markers of cerebral tau pathology suggestive of concomitant Alzheimer's disease.
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Lobar cerebral microbleeds are a characteristic neuroimaging finding in cerebral amyloid angiopathy (CAA) but can also be found in hypertensive arteriolosclerosis. We aimed to investigate whether CAA is more associated with intracortical lobar microbleeds than hypertensive arteriosclerosis. Ninety-one survivors of spontaneous intracerebral hemorrhage with at least one lobar microbleed were included and underwent brain MRI and amyloid PET. We categorized lobar microbleeds as intracortical, juxtacortical, or subcortical. We assessed the associations between the lobar microbleed categories and microangiopathy subtypes or cerebral amyloid load based on the Pittsburgh Compound-B PET standardized uptake value ratio (SUVR). Patients with CAA had a higher prevalence of intracortical lobar microbleeds (80.0% vs. 50.8%, P = 0.011) and lower prevalence of subcortical lobar microbleeds (13.3% vs. 60.1%, P < 0.001) than patients with hypertensive arteriolosclerosis. Strictly intracortical/juxtacortical lobar microbleeds were associated with CAA (OR 18.9 [1.9-191.4], P = 0.013), while the presence of subcortical lobar microbleeds was associated with hypertensive arteriolosclerosis (OR 10.9 [1.8-68.1], P = 0.010). Amyloid retention was higher in patients with strictly intracortical/juxtacortical CMBs than those without (SUVR = 1.15 [1.05-1.52] vs. 1.08 [1.02-1.19], P = 0.039). Amyloid retention positively correlated with the number of intracortical lobar microbleeds (P < 0.001) and negatively correlated with the number of subcortical lobar microbleeds (P = 0.018). CAA and cortical amyloid deposition are more strongly associated with strictly intracortical/juxtacortical microbleeds than subcortical lobar microbleeds. Categorization of lobar microbleeds based on anatomical location may help differentiate the underlying microangiopathy and potentially improve the accuracy of current neuroimaging criteria for cerebral small vessel disease.
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Arteriolosclerose , Angiopatia Amiloide Cerebral , Hipertensão , Humanos , Arteriolosclerose/complicações , Angiopatia Amiloide Cerebral/complicações , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Hemorragia Cerebral/complicações , Imageamento por Ressonância Magnética/métodos , Hipertensão/complicações , Hipertensão/diagnóstico por imagem , Amiloide , Proteínas AmiloidogênicasRESUMO
BACKGROUND: While using lymphovenous anastomosis (LVA) to treat extremity lymphedema, an antegrade lymphatic-to-venous flow is usually considered to indicate a functional and effective anastomosis. The authors analyzed the characteristics of lymphovenous anastomoses in patients with extremity lymphedema to look for the deciding factors of the flow direction. METHODS: A total of 45 patients (15 arms and 42 legs) undergoing LVA for extremity lymphedema were reviewed. Only the anastomoses with intraoperatively confirmed patent flow or clear visualization of vessel lumens during anastomosis were included for analysis. Multivariate logistic regression was used to identify the contributing factors of intraoperative washout phenomenon or venous reflux. RESULTS: A total of 105 eligible LVAs were included for analysis. Anastomosis with a more sclerotic lymphatic duct is statistically significantly associated with more venous reflux (OR, 2.82; P = 0.003). Larger diameter difference between lymphatic duct and recipient vein (OR, 12.8; P = 0.02) and less sclerotic lymphatic duct (OR, 0.47; P = 0.03) are statistically significantly associated with more washout phenomena. CONCLUSIONS: The deciding factors of flow direction in LVA are difference of diameters between lymphatic duct and recipient vein, and the severity of lymphosclerosis. To obtain favorable antegrade lymph-to-vein flow, a less sclerotic lymphatic duct with larger diameter and a recipient vein with smaller diameter should be chosen for anastomosis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.
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Vasos Linfáticos , Linfedema , Humanos , Procedimentos Cirúrgicos Vasculares , Veias/cirurgia , Linfedema/cirurgia , Vasos Linfáticos/cirurgia , Perna (Membro)/cirurgia , Anastomose Cirúrgica , Extremidade Inferior/cirurgiaRESUMO
BACKGROUND: To investigate the association between cerebral amyloid deposition and long-term cognitive outcomes in patients with hemorrhagic small vessel disease (SVD) and survivors of intracerebral hemorrhage (ICH). METHODS: Patients experiencing an ICH without overt dementia were prospectively recruited (n = 68) for brain MRI and Pittsburgh compound B (PiB) positron emission tomography scans at baseline. Cognitive function was assessed using the mini-mental status examination (MMSE) and clinical dementia rating after an overall median follow-up of 3.8 years. A positive amyloid scan was defined as a global PiB standardized uptake value ratio >1.2. Associations between follow-up cognitive outcomes and neuroimaging markers were explored using multivariable Cox regression models. RESULTS: PiB(+) patients were older (72.1 ± 7.8 vs. 59.9 ± 11.7, p = .002) and more frequently had cerebral amyloid angiopathy (CAA) (63.6% vs. 15.8%, p = .002) than PiB(-) patients. PiB(+) was associated with a higher risk of dementia conversion (32.9 vs. 4.0 per 100-person-years, hazard ratio [HR] = 15.7 [3.0-80.7], p = .001) and MMSE score decline (58.8 vs. 9.9 per 100-person-years, HR = 6.2 [1.9-20.0], p = .002). In the non-CAA subgroup (n = 52), PiB(+) remained an independent predictor of dementia conversion, p = .04). In the Cox models, PiB(+) was an independent predictor of dementia conversion (HR = 15.8 [2.6-95.4], p = .003) and MMSE score decline (HR = 5.7 [1.6-20.3], p = .008) after adjusting for confounders. CONCLUSIONS: Cerebral amyloid deposition potentially contributes to long-term cognitive decline in SVD-related ICH.
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Lung adenocarcinoma (ADC) is the most common non-small cell lung cancer. Surgical resection is the primary treatment for early-stage lung ADC while lung-sparing surgery is an alternative for non-aggressive cases. Identifying histopathologic subtypes before surgery helps determine the optimal surgical approach. Predominantly solid or micropapillary (MIP) subtypes are aggressive and associated with a higher likelihood of recurrence and metastasis and lower survival rates. This study aims to non-invasively identify these aggressive subtypes using preoperative 18F-FDG PET/CT and diagnostic CT radiomics analysis. We retrospectively studied 119 patients with stage I lung ADC and tumors ≤ 2 cm, where 23 had aggressive subtypes (18 solid and 5 MIPs). Out of 214 radiomic features from the PET/CT and CT scans and 14 clinical parameters, 78 significant features (3 CT and 75 PET features) were identified through univariate analysis and hierarchical clustering with minimized feature collinearity. A combination of Support Vector Machine classifier and Least Absolute Shrinkage and Selection Operator built predictive models. Ten iterations of 10-fold cross-validation (10 ×10-fold CV) evaluated the model. A pair of texture feature (PET GLCM Correlation) and shape feature (CT Sphericity) emerged as the best predictor. The radiomics model significantly outperformed the conventional predictor SUVmax (accuracy: 83.5% vs. 74.7%, p = 9e-9) and identified aggressive subtypes by evaluating FDG uptake in the tumor and tumor shape. It also demonstrated a high negative predictive value of 95.6% compared to SUVmax (88.2%, p = 2e-10). The proposed radiomics approach could reduce unnecessary extensive surgeries for non-aggressive subtype patients, improving surgical decision-making for early-stage lung ADC patients.
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BACKGROUND: Lymphovenous anastomosis (LVA) is an accepted method for treating lymphedema, and its efficacy could be greatly affected by the severity of lymphosclerosis. In the present study, we analyzed the intraoperative findings of lymphatic ducts in our patients who had undergone LVA to find predictive factors for the severity of lymphosclerosis. METHODS: The medical records of the patients who had undergone LVA for managing extremity lymphedema from September 2017 to December 2020 were reviewed. The severity of lymphosclerosis was evaluated intraoperatively under a surgical microscope and stratified using the NECST (normal, ectasia, contraction, sclerosis type) classification. Patient age, gender, body mass index (BMI), lymphoscintigraphy stage, and lymphatic duct locations were included for analysis. RESULTS: Multivariate linear regression analysis showed that location in a lower extremity (regression coefficient, -0.38; P = .03) and more advanced Taiwan lymphoscintigraphy stage (regression coefficient, 0.27; P < .001) were associated with more severe lymphosclerosis. In a subgroup analysis of lower extremity lymphedema, in addition to the Taiwan lymphoscintigraphy stage (regression coefficient, 0.24; P < .001), age (regression coefficient, 0.02; P = .001), and BMI (regression coefficient, 0.04; P = .005) were also associated with the severity of lymphosclerosis. CONCLUSIONS: The severity of lymphosclerosis in extremity lymphedema correlated positively with the Taiwan lymphoscintigraphy stage and was more severe in lower limb lymphedema. In lower limb lymphedema, a higher BMI and older age also contributed to more severe lymphosclerosis.
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Vasos Linfáticos , Linfedema , Anastomose Cirúrgica/métodos , Humanos , Extremidade Inferior/cirurgia , Vasos Linfáticos/diagnóstico por imagem , Vasos Linfáticos/cirurgia , Linfedema/diagnóstico por imagem , Linfedema/etiologia , Linfedema/cirurgia , Linfocintigrafia/métodosRESUMO
BACKGROUND: Myocardial perfusion imaging (MPI) is a well-established diagnostic tool to evaluate coronary artery disease (CAD) and also an effective prognostic tool for patients with CAD. However, few studies investigated the prognostic value of attenuation correction (AC) in MPI, and the results were controversial. OBJECTIVES: To investigate the prognostic value of computed tomography (CT)-based AC thallium-201 (Tl-201) MPI. METHODS: A total of 108 consecutive patients who underwent Tl-201 MPI and received coronary angiography within 90 days were included. Medical records were reviewed and missing information was completed after telephone contact. The prognostic value was evaluated by Kaplan-Meier analysis, univariable and multivariable Cox proportional hazards model. RESULTS: After a mean follow-up of 7.72 ± 3.72 years, 27 patients had died, 41 had been readmitted for cardiovascular (CV)-related events and 44 had reached the composite of death plus CV-related re-admission. Kaplan-Meier curves for all-cause mortality for SSS with a cutoff value of 13 for AC and 16 for non-AC (NAC) images showed a significant difference between the two curves for both AC and NAC images (p = 0.011 for AC and p = 0.021 for NAC). In the multivariable model, SSS and SRS showed similar independent predictive values in predicting all-cause mortality and composite of all-cause mortality plus CV-related re-admission, in both AC and NAC images. Subgroup analysis implicated that AC MPI possibly provided better risk stratification in obese patients. CONCLUSION: CT-based AC and NAC MPI showed similar value and were the only significant predictors for the composite of mortality and CV events.
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Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio , Tomografia Computadorizada por Raios X , Idoso , Doença da Artéria Coronariana/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Radioisótopos de TálioRESUMO
BACKGROUND: Among various bio-informative molecules transferred by exosomes between cells, micro RNAs (miRNAs), which remain remarkably stable even after freeze-and-thaw cycles, are excellent candidates for potential biomarkers for coronary artery disease (CAD). METHODS: Blood samples were collected from the coronary arteries of 214 patients diagnosed with three-vessel CAD and 140 without CAD. After precipitation extraction, the amounts of exosomes were found to decrease with increased age and three-vessel CAD. Next-generation sequencing was performed to further explore the possible relationship between exosomal miRNAs and CAD. RESULTS: Eight exosomal miRNAs showed altered expression associated with CAD. The up-regulated miRNAs in CAD were miRNA-382-3p, miRNA-432-5p, miRNA-200a-3p, and miRNA-3613-3p. The down-regulated miRNAs were miRNA-125a-5p, miRNA-185-5p, miRNA-151a-3p, and miRNA-328-3p. CONCLUSION: We successfully demonstrated particular exosomal miRNAs that may serve as future biomarkers for CAD.
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Doença da Artéria Coronariana/genética , Exossomos/genética , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/genética , Idoso , Feminino , Humanos , Modelos Lineares , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-IdadeRESUMO
Volumetric lung tumor segmentation and accurate longitudinal tracking of tumor volume changes from computed tomography images are essential for monitoring tumor response to therapy. Hence, we developed two multiple resolution residually connected network (MRRN) formulations called incremental-MRRN and dense-MRRN. Our networks simultaneously combine features across multiple image resolution and feature levels through residual connections to detect and segment the lung tumors. We evaluated our method on a total of 1210 non-small cell (NSCLC) lung tumors and nodules from three data sets consisting of 377 tumors from the open-source Cancer Imaging Archive (TCIA), 304 advanced stage NSCLC treated with anti- PD-1 checkpoint immunotherapy from internal institution MSKCC data set, and 529 lung nodules from the Lung Image Database Consortium (LIDC). The algorithm was trained using 377 tumors from the TCIA data set and validated on the MSKCC and tested on LIDC data sets. The segmentation accuracy compared to expert delineations was evaluated by computing the dice similarity coefficient, Hausdorff distances, sensitivity, and precision metrics. Our best performing incremental-MRRN method produced the highest DSC of 0.74 ± 0.13 for TCIA, 0.75±0.12 for MSKCC, and 0.68±0.23 for the LIDC data sets. There was no significant difference in the estimations of volumetric tumor changes computed using the incremental-MRRN method compared with the expert segmentation. In summary, we have developed a multi-scale CNN approach for volumetrically segmenting lung tumors which enables accurate, automated identification of and serial measurement of tumor volumes in the lung.
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Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Bases de Dados Factuais , Aprendizado Profundo , Humanos , Pulmão/diagnóstico por imagemRESUMO
Normal lung CT texture features have been used for the prediction of radiation-induced lung disease (RILD). For these features to be clinically useful, they should be robust to tumor size variations and not correlated with the normal lung volume of interest, i.e., the volume of the peri-tumoral region (PTR). CT images of 14 lung cancer patients were studied. Different sizes of gross tumor volumes (GTVs) were simulated and placed in the lung contralateral to the tumor. 27 texture features [nine from intensity histogram, eight from the gray-level co-occurrence matrix (GLCM) and ten from the gray-level run-length matrix (GLRM)] were extracted from the PTR. The Bland-Altman analysis was applied to measure the normalized range of agreement (nRoA) for each feature when GTV size varied. A feature was considered as robust when its nRoA was less than the threshold (100%). Sixteen texture features were identified as robust. None of the robust features was correlated with the volume of the PTR. No feature showed statistically significant differences (P<0.05) on GTV locations. We identified 16 robust normal lung CT texture features that can be further examined for the prediction of RILD.
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We proposed a framework to detect and quantify local tumor morphological changes due to chemo-radiotherapy (CRT) using a Jacobian map and to extract quantitative radiomic features from the Jacobian map to predict the pathologic tumor response in locally advanced esophageal cancer patients. In 20 patients who underwent CRT, a multi-resolution BSpline deformable registration was performed to register the follow-up (post-CRT) CT to the baseline CT image. The Jacobian map (J) was computed as the determinant of the gradient of the deformation vector field. The Jacobian map measured the ratio of local tumor volume change where J < 1 indicated tumor shrinkage and J > 1 denoted expansion. The tumor was manually delineated and corresponding anatomical landmarks were generated on the baseline and follow-up images. Intensity, texture and geometry features were then extracted from the Jacobian map of the tumor to quantify tumor morphological changes. The importance of each Jacobian feature in predicting pathologic tumor response was evaluated by both univariate and multivariate analysis. We constructed a multivariate prediction model by using a support vector machine (SVM) classifier coupled with a least absolute shrinkage and selection operator (LASSO) for feature selection. The SVM-LASSO model was evaluated using ten-times repeated 10-fold cross-validation (10 × 10-fold CV). After registration, the average target registration error was 4.30 ± 1.09 mm (LR:1.63 mm AP:1.59 mm SI:3.05 mm) indicating registration error was within two voxels and close to 4 mm slice thickness. Visually, the Jacobian map showed smoothly-varying local shrinkage and expansion regions in a tumor. Quantitatively, the average median Jacobian was 0.80 ± 0.10 and 1.05 ± 0.15 for responder and non-responder tumors, respectively. These indicated that on average responder tumors had 20% median volume shrinkage while non-responder tumors had 5% median volume expansion. In univariate analysis, the minimum Jacobian (p = 0.009, AUC = 0.98) and median Jacobian (p = 0.004, AUC = 0.95) were the most significant predictors. The SVM-LASSO model achieved the highest accuracy when these two features were selected (sensitivity = 94.4%, specificity = 91.8%, AUC = 0.94). Novel features extracted from the Jacobian map quantified local tumor morphological changes using only baseline tumor contour without post-treatment tumor segmentation. The SVM-LASSO model using the median Jacobian and minimum Jacobian achieved high accuracy in predicting pathologic tumor response. The Jacobian map showed great potential for longitudinal evaluation of tumor response.
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Quimiorradioterapia/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Esofagectomia/métodos , Processamento de Imagem Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Terapia Combinada , Neoplasias Esofágicas/terapia , Humanos , Estudos Retrospectivos , Máquina de Vetores de Suporte , Carga TumoralRESUMO
PURPOSE: To develop a radiomics prediction model to improve pulmonary nodule (PN) classification in low-dose CT. To compare the model with the American College of Radiology (ACR) Lung CT Screening Reporting and Data System (Lung-RADS) for early detection of lung cancer. METHODS: We examined a set of 72 PNs (31 benign and 41 malignant) from the Lung Image Database Consortium image collection (LIDC-IDRI). One hundred three CT radiomic features were extracted from each PN. Before the model building process, distinctive features were identified using a hierarchical clustering method. We then constructed a prediction model by using a support vector machine (SVM) classifier coupled with a least absolute shrinkage and selection operator (LASSO). A tenfold cross-validation (CV) was repeated ten times (10 × 10-fold CV) to evaluate the accuracy of the SVM-LASSO model. Finally, the best model from the 10 × 10-fold CV was further evaluated using 20 × 5- and 50 × 2-fold CVs. RESULTS: The best SVM-LASSO model consisted of only two features: the bounding box anterior-posterior dimension (BB_AP) and the standard deviation of inverse difference moment (SD_IDM). The BB_AP measured the extension of a PN in the anterior-posterior direction and was highly correlated (r = 0.94) with the PN size. The SD_IDM was a texture feature that measured the directional variation of the local homogeneity feature IDM. Univariate analysis showed that both features were statistically significant and discriminative (P = 0.00013 and 0.000038, respectively). PNs with larger BB_AP or smaller SD_IDM were more likely malignant. The 10 × 10-fold CV of the best SVM model using the two features achieved an accuracy of 84.6% and 0.89 AUC. By comparison, Lung-RADS achieved an accuracy of 72.2% and 0.77 AUC using four features (size, type, calcification, and spiculation). The prediction improvement of SVM-LASSO comparing to Lung-RADS was statistically significant (McNemar's test P = 0.026). Lung-RADS misclassified 19 cases because it was mainly based on PN size, whereas the SVM-LASSO model correctly classified 10 of these cases by combining a size (BB_AP) feature and a texture (SD_IDM) feature. The performance of the SVM-LASSO model was stable when leaving more patients out with five- and twofold CVs (accuracy 84.1% and 81.6%, respectively). CONCLUSION: We developed an SVM-LASSO model to predict malignancy of PNs with two CT radiomic features. We demonstrated that the model achieved an accuracy of 84.6%, which was 12.4% higher than Lung-RADS.
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Detecção Precoce de Câncer , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Doses de Radiação , Tomografia Computadorizada por Raios X , Máquina de Vetores de SuporteRESUMO
Autoimmune pancreatitis (AIP) shares overlapping clinical features with pancreatic cancer (PC). Importantly, treatment of the two conditions is different. We investigated the clinical usefulness of 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with suspected AIP before treatment. From September 2008 to July 2016, 53 patients with suspected AIP at National Taiwan University Hospital had PET/CT prior to therapy to exclude malignancy and evaluate the extent of inflammation. Their scans were compared with those from 61 PC patients. PET imaging features were analyzed using logistic regression. Significant differences in pancreatic tumor uptake morphology, maximum standardized uptake value, high-order primary tumor texture feature (i.e. high-gray level zone emphasis value), and numbers and location of extrapancreatic foci were found between AIP and PC. Using the prediction model, the area under curve of receiver-operator curve was 0.95 (P < 0.0001) with sensitivity, specificity, positive predictive, and negative predictive values of 90.6%, 84.0%, 87.9%, and 87.5% respectively, in differentiating AIP from PC. FDG PET/CT offers high sensitivity, albeit slightly lower specificity in differentiating AIP from PC. Nonetheless, additional systemic inflammatory foci detected by the whole body PET/CT help confirm diagnosis of AIP in these patients before initiating steroid therapy, especially when biopsy is inconclusive.
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Doenças Autoimunes/diagnóstico por imagem , Pancreatite/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos de Casos e Controles , Diagnóstico Diferencial , Fluordesoxiglucose F18 , Humanos , Modelos Logísticos , Neoplasias Pancreáticas/diagnóstico por imagemRESUMO
A 68-year-old man with diabetes mellitus type 2 presented himself with visual distortion and apraxia. Nonketotic hyperglycemic seizure with both motor and sensory components was suspected. Tc-ECD perfusion SPECT demonstrated hyperperfusion at right parieto-occipital lobe during ictal phase. Normalization of hyperperfused area was noted on follow-up perfusion SPECT after intense glucose control. In nonketotic hyperglycemic state, the depletion of GABA in cerebral neurons lowers the seizure threshold. We demonstrated that ictal phase perfusion SPECT contributed to not only diagnosis but also served as a follow-up tool.
Assuntos
Hiperglicemia/complicações , Imagem de Perfusão , Convulsões/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Cisteína/análogos & derivados , Humanos , Masculino , Lobo Occipital/diagnóstico por imagem , Compostos de Organotecnécio , Lobo Parietal/diagnóstico por imagem , Compostos Radiofarmacêuticos , Convulsões/etiologiaRESUMO
PURPOSE: This study determined the prognostic value of volumetric parameters derived from pretreatment F-FDG and F-DOPA PET/CT of neuroblastoma and their correlation with clinical and histopathologic features. PATIENTS AND METHODS: A total of 25 children with neuroblastoma underwent pretreatment F-FDG and F-DOPA PET/CT within 4 weeks. The SUVmax of primary tumors on F-FDG and F-DOPA PET were recorded as SUVFDG and SUVDOPA, respectively. For volumetric parameters of primary tumors, 40% of SUVmax was used to generate volume of interest. If the 40% of SUVmax was below 2.5, an SUV threshold of 2.5 was used instead. Metabolic tumor volume (MTV), total lesion glycolysis (TLG), dopaminergic tumor volume (DTV), and total lesion F-DOPA activity (TLDA) were recorded as F-FDG and F-DOPA volumetric parameters. All indices were compared between groups distinguished by survival status and clinical features, including bone marrow involvement, lymph node metastasis, amplification of the MYCN oncogene, invasive features on anatomic images, and risk categories. The Kaplan-Meier method and log-rank test were used to compare the survival curves between groups. RESULTS: The median follow-up period was 28.2 months. Nonsurvivors (20%) tended to have lower SUVDOPA, DTV, and TLDA (P ≤ 0.05), and higher SUVFDG, MTV, and TLG (all P < 0.05). Lower F-DOPA uptake is associated with bone marrow and lymph node metastases (all P < 0.05). Higher F-FDG uptake is associated with MYCN amplification (all P < 0.05) and anatomic invasive features of tumors such as vascular encasement or adjacent organ invasion (TLG, P = 0.05). Only volumetric indices (DTV, TLDA, MTV, and TLG) significantly differed among risk groups (all P < 0.05). CONCLUSIONS: Pretherapeutic F-DOPA and F-FDG PET provided complementary information, and both can be served for risk stratification. Volumetric indices of F-DOPA and F-FDG PET correlate more highly with risk grouping.