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1.
Lung Cancer ; 194: 107890, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39003936

RESUMO

INTRODUCTION: Histological confirmation of a lung tumor is the prerequisite for treatment planning. It has been suspected that CT-guided needle biopsy (CTGNB) exposes the patient to a higher risk of pleural recurrence. However, the distance between tumor and pleura has largely been neglected as a possible confounder when comparing CTGNB to bronchoscopy. METHODS: All patients with lung cancer histologically confirmed by bronchoscopy or CTGNB between 2010 and 2020 were enrolled and studied. Patients' medical histories, radiologic and pathologic findings and surgical records were reviewed. Pleural recurrence was diagnosed by pleural biopsy, fluid cytology, or by CT chest imaging showing progressive pleural nodules. RESULTS: In this retrospective unicenter analysis, 844 patients underwent curative resection for early-stage lung cancer between 2010 and 2020. Median follow-up was 47.5 months (3-137). 27 patients (3.2 %) with ipsilateral pleural recurrence (IPR) were identified. The distance of the tumor to the pleura was significantly smaller in patients who underwent CTGNB. A tendency of increased risk of IPR was observed in tumors located in the lower lobe (HR: 2.18 [±0.43], p = 0.068), but only microscopic pleural invasion was a significant independent predictive factor for increased risk of IPR (HR: 5.33 [± 0.51], p = 0.001) by multivariate cox analysis. Biopsy by CTGNB did not affect IPR (HR: 1.298 [± 0.39], p = 0.504). CONCLUSION: CTGNB is safe and not associated with an increased incidence of IPR in our cohort of patients. This observation remains to be validated in a larger multicenter patient cohort.


Assuntos
Biópsia Guiada por Imagem , Neoplasias Pulmonares , Neoplasias Pleurais , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Neoplasias Pleurais/secundário , Neoplasias Pleurais/patologia , Neoplasias Pleurais/diagnóstico por imagem , Neoplasias Pleurais/diagnóstico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/diagnóstico , Estudos Retrospectivos , Idoso , Tomografia Computadorizada por Raios X/métodos , Biópsia Guiada por Imagem/métodos , Pessoa de Meia-Idade , Pleura/patologia , Pleura/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Seguimentos , Idoso de 80 Anos ou mais , Biópsia por Agulha/métodos , Adulto
2.
Artigo em Inglês | MEDLINE | ID: mdl-38523120

RESUMO

INTRODUCTION: Clinical clearance of a child's cervical spine after trauma is often challenging due to impaired mental status or an unreliable neurologic examination. Magnetic resonance imaging (MRI) is the gold standard for excluding ligamentous injury in children but is constrained by long image acquisition times and frequent need for anesthesia. Limited-sequence MRI (LSMRI) is used in evaluating the evolution of traumatic brain injury and may also be useful for cervical spine clearance while potentially avoiding the need for anesthesia. The purpose of this study was to assess the sensitivity and negative predictive value of LSMRI as compared to gold standard full-sequence MRI as a screening tool to rule out clinically significant ligamentous cervical spine injury. METHODS: We conducted a ten-center, five-year retrospective cohort study (2017-2021) of all children (0-18y) with a cervical spine MRI after blunt trauma. MRI images were re-reviewed by a study pediatric radiologist at each site to determine if the presence of an injury could be identified on limited sequences alone. Unstable cervical spine injury was determined by study neurosurgeon review at each site. RESULTS: We identified 2,663 children less than 18 years of age who underwent an MRI of the cervical spine with 1,008 injuries detected on full-sequence studies. The sensitivity and negative predictive value of LSMRI were both >99% for detecting any injury and 100% for detecting any unstable injury. Young children (age < 5 years) were more likely to be electively intubated or sedated for cervical spine MRI. CONCLUSION: LSMRI is reliably detects clinically significant ligamentous injury in children after blunt trauma. To decrease anesthesia use and minimize MRI time, trauma centers should develop LSMRI screening protocols for children without a reliable neurologic exam. LEVEL OF EVIDENCE: 2 (Diagnostic Tests or Criteria).

3.
AJNR Am J Neuroradiol ; 45(4): 453-460, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38453410

RESUMO

BACKGROUND AND PURPOSE: MR perfusion has shown value in the evaluation of posttreatment high-grade gliomas, but few studies have shown its impact on the consistency and confidence of neuroradiologists' interpretation in routine clinical practice. We evaluated the impact of adding MR perfusion metrics to conventional contrast-enhanced MR imaging in posttreatment high-grade glioma surveillance imaging. MATERIALS AND METHODS: This retrospective study included 45 adults with high-grade gliomas who had posttreatment perfusion MR imaging. Four neuroradiologists assigned Brain Tumor Reporting and Data System scores for each examination on the basis of the interpretation of contrast-enhanced MR imaging and then after the addition of arterial spin-labeling-CBF, DSC-relative CBV, and DSC-fractional tumor burden. Interrater agreement and rater agreement with a multidisciplinary consensus group were assessed with κ statistics. Raters used a 5-point Likert scale to report confidence scores. The frequency of clinically meaningful score changes resulting from the addition of each perfusion metric was determined. RESULTS: Interrater agreement was moderate for contrast-enhanced MR imaging alone (κ = 0.63) and higher with perfusion metrics (arterial spin-labeling-CBF, κ = 0.67; DSC-relative CBV, κ = 0.66; DSC-fractional tumor burden, κ = 0.70). Agreement between raters and consensus was highest with DSC-fractional tumor burden (κ = 0.66-0.80). Confidence scores were highest with DSC-fractional tumor burden. Across all raters, the addition of perfusion resulted in clinically meaningful interpretation changes in 2%-20% of patients compared with contrast-enhanced MR imaging alone. CONCLUSIONS: Adding perfusion to contrast-enhanced MR imaging improved interrater agreement, rater agreement with consensus, and rater confidence in the interpretation of posttreatment high-grade glioma MR imaging, with the highest agreement and confidence scores seen with DSC-fractional tumor burden. Perfusion MR imaging also resulted in interpretation changes that could change therapeutic management in up to 20% of patients.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Estudos Retrospectivos , Marcadores de Spin , Glioma/diagnóstico por imagem , Glioma/terapia , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Perfusão , Meios de Contraste , Circulação Cerebrovascular
4.
BMC Med Inform Decis Mak ; 24(1): 40, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326769

RESUMO

BACKGROUND: Deep learning has demonstrated significant advancements across various domains. However, its implementation in specialized areas, such as medical settings, remains approached with caution. In these high-stake environments, understanding the model's decision-making process is critical. This study assesses the performance of different pretrained Bidirectional Encoder Representations from Transformers (BERT) models and delves into understanding its decision-making within the context of medical image protocol assignment. METHODS: Four different pre-trained BERT models (BERT, BioBERT, ClinicalBERT, RoBERTa) were fine-tuned for the medical image protocol classification task. Word importance was measured by attributing the classification output to every word using a gradient-based method. Subsequently, a trained radiologist reviewed the resulting word importance scores to assess the model's decision-making process relative to human reasoning. RESULTS: The BERT model came close to human performance on our test set. The BERT model successfully identified relevant words indicative of the target protocol. Analysis of important words in misclassifications revealed potential systematic errors in the model. CONCLUSIONS: The BERT model shows promise in medical image protocol assignment by reaching near human level performance and identifying key words effectively. The detection of systematic errors paves the way for further refinements to enhance its safety and utility in clinical settings.


Assuntos
Processamento de Linguagem Natural , Resolução de Problemas , Humanos
5.
Ann Biomed Eng ; 52(6): 1568-1575, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38402314

RESUMO

Dynamic susceptibility contrast magnetic resonance perfusion (DSC-MRP) is a non-invasive imaging technique for hemodynamic measurements. Various perfusion parameters, such as cerebral blood volume (CBV) and cerebral blood flow (CBF), can be derived from DSC-MRP, hence this non-invasive imaging protocol is widely used clinically for the diagnosis and assessment of intracranial pathologies. Currently, most institutions use commercially available software to compute the perfusion parametric maps. However, these conventional methods often have limitations, such as being time-consuming and sensitive to user input, which can lead to inconsistent results; this highlights the need for a more robust and efficient approach like deep learning. Using the relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) perfusion maps generated by FDA-approved software, we trained a multistage deep learning model. The model, featuring a combination of a 1D convolutional neural network (CNN) and a 2D U-Net encoder-decoder network, processes each 4D MRP dataset by integrating temporal and spatial features of the brain for voxel-wise perfusion parameters prediction. An auxiliary model, with similar architecture, but trained with truncated datasets that had fewer time-points, was designed to explore the contribution of temporal features. Both qualitatively and quantitatively evaluated, deep learning-generated rCBV and rCBF maps showcased effective integration of temporal and spatial data, producing comprehensive predictions for the entire brain volume. Our deep learning model provides a robust and efficient approach for calculating perfusion parameters, demonstrating comparable performance to FDA-approved commercial software, and potentially mitigating the challenges inherent to traditional techniques.


Assuntos
Volume Sanguíneo Cerebral , Circulação Cerebrovascular , Aprendizado Profundo , Humanos , Circulação Cerebrovascular/fisiologia , Volume Sanguíneo Cerebral/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Feminino , Adulto
6.
J Magn Reson Imaging ; 59(4): 1349-1357, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37515518

RESUMO

BACKGROUND: Cerebrovascular reserve (CVR) reflects the capacity of cerebral blood flow (CBF) to change following a vasodilation challenge. Decreased CVR is associated with a higher stroke risk in patients with cerebrovascular diseases. While revascularization can improve CVR and reduce this risk in adult patients with vasculopathy such as those with Moyamoya disease, its impact on hemodynamics in pediatric patients remains to be elucidated. Arterial spin labeling (ASL) is a quantitative MRI technique that can measure CBF, CVR, and arterial transit time (ATT) non-invasively. PURPOSE: To investigate the short- and long-term changes in hemodynamics after bypass surgeries in patients with Moyamoya disease. STUDY TYPE: Longitudinal. POPULATION: Forty-six patients (11 months-18 years, 28 females) with Moyamoya disease. FIELD STRENGTH/SEQUENCE: 3-T, single- and multi-delay ASL, T1-weighted, T2-FLAIR, 3D MRA. ASSESSMENT: Imaging was performed 2 weeks before and 1 week and 6 months after surgical intervention. Acetazolamide was employed to induce vasodilation during the imaging procedure. CBF and ATT were measured by fitting the ASL data to the general kinetic model. CVR was computed as the percentage change in CBF. The mean CBF, ATT, and CVR values were measured in the regions affected by vasculopathy. STATISTICAL TESTS: Pre- and post-revascularization CVR, CBF, and ATT were compared for different regions of the brain. P-values <0.05 were considered statistically significant. RESULTS: ASL-derived CBF in flow territories affected by vasculopathy significantly increased after bypass by 41 ± 31% within a week. At 6 months, CBF significantly increased by 51 ± 34%, CVR increased by 68 ± 33%, and ATT was significantly reduced by 6.6 ± 2.9%. DATA CONCLUSION: There may be short- and long-term improvement in the hemodynamic parameters of pediatric Moyamoya patients after bypass surgery. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.


Assuntos
Doença de Moyamoya , Adulto , Feminino , Humanos , Criança , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Imageamento por Ressonância Magnética/métodos , Encéfalo , Hemodinâmica , Circulação Cerebrovascular/fisiologia , Marcadores de Spin
7.
J Magn Reson Imaging ; 59(1): 70-81, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37170640

RESUMO

Cerebral blood flow (CBF) is an important hemodynamic parameter to evaluate brain health. It can be obtained quantitatively using medical imaging modalities such as magnetic resonance imaging and positron emission tomography (PET). Although CBF in adults has been widely studied and linked with cerebrovascular and neurodegenerative diseases, CBF data in healthy children are sparse due to the challenges in pediatric neuroimaging. An understanding of the factors affecting pediatric CBF and its normal range is crucial to determine the optimal CBF measuring techniques in pediatric neuroradiology. This review focuses on pediatric CBF studies using neuroimaging techniques in 32 articles including 2668 normal subjects ranging from birth to 18 years old. A systematic literature search was conducted in PubMed, Embase, and Scopus and reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA). We identified factors (such as age, gender, mood, sedation, and fitness) that have significant effects on pediatric CBF quantification. We also investigated factors influencing the CBF measurements in infants. Based on this review, we recommend best practices to improve CBF measurements in pediatric neuroimaging. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.


Assuntos
Imageamento por Ressonância Magnética , Neuroimagem , Adulto , Lactente , Humanos , Criança , Neuroimagem/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Marcadores de Spin
8.
Proc Natl Acad Sci U S A ; 120(50): e2221510120, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38064507

RESUMO

Effort-based decisions, in which people weigh potential future rewards against effort costs required to achieve those rewards involve both cognitive and physical effort, though the mechanistic relationship between them is not yet understood. Here, we use an individual differences approach to isolate and measure the computational processes underlying effort-based decisions and test the association between cognitive and physical domains. Patch foraging is an ecologically valid reward rate maximization problem with well-developed theoretical tools. We developed the Effort Foraging Task, which embedded cognitive or physical effort into patch foraging, to quantify the cost of both cognitive and physical effort indirectly, by their effects on foraging choices. Participants chose between harvesting a depleting patch, or traveling to a new patch that was costly in time and effort. Participants' exit thresholds (reflecting the reward they expected to receive by harvesting when they chose to travel to a new patch) were sensitive to cognitive and physical effort demands, allowing us to quantify the perceived effort cost in monetary terms. The indirect sequential choice style revealed effort-seeking behavior in a minority of participants (preferring high over low effort) that has apparently been missed by many previous approaches. Individual differences in cognitive and physical effort costs were positively correlated, suggesting that these are perceived and processed in common. We used canonical correlation analysis to probe the relationship of task measures to self-reported affect and motivation, and found correlations of cognitive effort with anxiety, cognitive function, behavioral activation, and self-efficacy, but no similar correlations with physical effort.


Assuntos
Tomada de Decisões , Esforço Físico , Humanos , Tomada de Decisões/fisiologia , Esforço Físico/fisiologia , Individualidade , Cognição/fisiologia , Recompensa , Motivação
11.
bioRxiv ; 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37034586

RESUMO

Introduction: Spatio-temporal MRI methods enable whole-brain multi-parametric mapping at ultra-fast acquisition times through efficient k-space encoding, but can have very long reconstruction times, which limit their integration into clinical practice. Deep learning (DL) is a promising approach to accelerate reconstruction, but can be computationally intensive to train and deploy due to the large dimensionality of spatio-temporal MRI. DL methods also need large training data sets and can produce results that don't match the acquired data if data consistency is not enforced. The aim of this project is to reduce reconstruction time using DL whilst simultaneously limiting the risk of deep learning induced hallucinations, all with modest hardware requirements. Methods: Deep Learning Initialized Compressed Sensing (Deli-CS) is proposed to reduce the reconstruction time of iterative reconstructions by "kick-starting" the iterative reconstruction with a DL generated starting point. The proposed framework is applied to volumetric multi-axis spiral projection MRF that achieves whole-brain T1 and T2 mapping at 1-mm isotropic resolution for a 2-minute acquisition. First, the traditional reconstruction is optimized from over two hours to less than 40 minutes while using more than 90% less RAM and only 4.7 GB GPU memory, by using a memory-efficient GPU implementation. The Deli-CS framework is then implemented and evaluated against the above reconstruction. Results: Deli-CS achieves comparable reconstruction quality with 50% fewer iterations bringing the full reconstruction time to 20 minutes. Conclusion: Deli-CS reduces the reconstruction time of subspace reconstruction of volumetric spatio-temporal acquisitions by providing a warm start to the iterative reconstruction algorithm.

12.
Sci Transl Med ; 15(689): eabo4919, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36989377

RESUMO

Circuit-based mechanisms mediating the development and execution of habitual behaviors involve complex cortical-striatal interactions that have been investigated in animal models and more recently in humans. However, how human brain circuits implicated in habit formation may be perturbed in psychiatric disorders remains unclear. First, we identified the locations of the sensorimotor putamen and associative caudate in the human brain using probabilistic tractography from Human Connectome Project data. We found that multivariate connectivity of the sensorimotor putamen was altered in humans with binge eating disorder and bulimia nervosa and that the degree of alteration correlated with severity of disordered eating behavior. Furthermore, the extent of this circuit aberration correlated with mean diffusivity in the sensorimotor putamen and decreased basal dopamine D2/3 receptor binding potential in the striatum, consistent with previously reported microstructural changes and dopamine signaling mediating habit learning in animal models. Our findings suggest a neural circuit that links habit learning and binge eating behavior in humans, which could, in part, explain the treatment-resistant behavior common to eating disorders and other psychiatric conditions.


Assuntos
Bulimia Nervosa , Transtornos da Alimentação e da Ingestão de Alimentos , Animais , Humanos , Dopamina/metabolismo , Transtornos da Alimentação e da Ingestão de Alimentos/metabolismo , Encéfalo/metabolismo , Bulimia Nervosa/metabolismo , Bulimia Nervosa/psicologia , Hábitos
13.
J Cereb Blood Flow Metab ; 43(2_suppl): 138-151, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36408536

RESUMO

Cerebrovascular reserve (CVR) reflects the capacity of cerebral blood flow (CBF) to change. Decreased CVR implies poor hemodynamics and is linked to a higher risk for stroke. Revascularization has been shown to improve CBF in patients with vasculopathy such as Moyamoya disease. Dynamic susceptibility contrast (DSC) can measure transit time to evaluate patients suspected of stroke. Arterial spin labeling (ASL) is a non-invasive technique for CBF, CVR, and arterial transit time (ATT) measurements. Here, we investigate the change in hemodynamics 4-12 months after extracranial-to-intracranial direct bypass in 52 Moyamoya patients using ASL with single and multiple post-labeling delays (PLD). Images were collected using ASL and DSC with acetazolamide. CVR, CBF, ATT, and time-to-maximum (Tmax) were measured in different flow territories. Results showed that hemodynamics improved significantly in regions affected by arterial occlusions after revascularization. CVR increased by 16 ± 11% (p < 0.01) and 25 ± 13% (p < 0.01) for single- and multi-PLD ASL, respectively. Transit time measured by multi-PLD ASL and post-vasodilation DSC reduced by 13 ± 7% (p < 0.01) and 9 ± 5% (p < 0.01), respectively. For all regions, ATT correlated significantly with Tmax (R2 = 0.59, p < 0.01). Thus, revascularization improved CVR and decreased transit times. Multi-PLD ASL can serve as an effective and non-invasive modality to examine vascular hemodynamics in Moyamoya patients.


Assuntos
Doença de Moyamoya , Acidente Vascular Cerebral , Humanos , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Imageamento por Ressonância Magnética/métodos , Artérias , Hemodinâmica , Circulação Cerebrovascular/fisiologia , Marcadores de Spin
14.
Sci Rep ; 12(1): 20729, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456574

RESUMO

Asynchronous calibration could allow opportunistic screening based on routine CT for early osteoporosis detection. In this phantom study, a bone mineral density (BMD) calibration phantom and multi-energy CT (MECT) phantom were imaged on eight different CT scanners with multiple tube voltages (80-150 kVp) and image reconstruction settings (e.g. soft/hard kernel). Reference values for asynchronous BMD estimation were calculated from the BMD-phantom and validated with six calcium composite inserts of the MECT-phantom with known ground truth. Relative errors/changes in estimated BMD were calculated and investigated for influence of tube voltage, CT scanner and reconstruction setting. Reference values for 282 acquisitions were determined, resulting in an average relative error between calculated BMD and ground truth of - 9.2% ± 14.0% with a strong correlation (R2 = 0.99; p < 0.0001). Tube voltage and CT scanner had a significant effect on calculated BMD (p < 0.0001), with relative differences in BMD of 3.8% ± 28.2% when adapting reference values for tube voltage, - 5.6% ± 9.2% for CT scanner and 0.2% ± 0.2% for reconstruction setting, respectively. Differences in BMD were small when using reference values from a different CT scanner of the same model (0.0% ± 1.4%). Asynchronous phantom-based calibration is feasible for opportunistic BMD assessment based on CT images with reference values adapted for tube voltage and CT scanner model.


Assuntos
Densidade Óssea , Osteoporose , Humanos , Calibragem , Osteoporose/diagnóstico por imagem , Imagens de Fantasmas , Tomografia Computadorizada por Raios X
15.
Healthcare (Basel) ; 10(11)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36360507

RESUMO

Automated image analysis plays an increasing role in radiology in detecting and quantifying image features outside of the perception of human eyes. Common AI-based approaches address a single medical problem, although patients often present with multiple interacting, frequently subclinical medical conditions. A holistic imaging diagnostics tool based on artificial intelligence (AI) has the potential of providing an overview of multi-system comorbidities within a single workflow. An interdisciplinary, multicentric team of medical experts and computer scientists designed a pipeline, comprising AI-based tools for the automated detection, quantification and characterization of the most common pulmonary, metabolic, cardiovascular and musculoskeletal comorbidities in chest computed tomography (CT). To provide a comprehensive evaluation of each patient, a multidimensional workflow was established with algorithms operating synchronously on a decentralized Joined Imaging Platform (JIP). The results of each patient are transferred to a dedicated database and summarized as a structured report with reference to available reference values and annotated sample images of detected pathologies. Hence, this tool allows for the comprehensive, large-scale analysis of imaging-biomarkers of comorbidities in chest CT, first in science and then in clinical routine. Moreover, this tool accommodates the quantitative analysis and classification of each pathology, providing integral diagnostic and prognostic value, and subsequently leading to improved preventive patient care and further possibilities for future studies.

16.
Neurosurgery ; 91(5): 710-716, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36084178

RESUMO

BACKGROUND: Moya Moya disease (MMD) and Moya Moya syndrome (MMS) are cerebrovascular disorders, which affect the internal carotid arteries (ICAs). Diagnosis and surveillance of MMD/MMS in children mostly rely on qualitative evaluation of vascular imaging, especially MR angiography (MRA). OBJECTIVE: To quantitatively characterize arterial differences in pediatric patients with MMD/MMS compared with normal controls. METHODS: MRA data sets from 17 presurgery MMD/MMS (10M/7F, mean age = 10.0 years) patients were retrospectively collected and compared with MRA data sets of 98 children with normal vessel morphology (49 male patients; mean age = 10.6 years). Using a level set segmentation method with anisotropic energy weights, the cerebral arteries were automatically extracted and used to compute the radius of the ICA, middle cerebral artery (MCA), anterior cerebral artery (ACA), posterior cerebral artery (PCA), and basilar artery (BA). Moreover, the density and the average radius of all arteries in the MCA, ACA, and PCA flow territories were quantified. RESULTS: Statistical analysis revealed significant differences comparing children with MMD/MMS and those with normal vasculature ( P < .001), whereas post hoc analyses identified significantly smaller radii of the ICA, MCA-M1, MCA-M2, and ACA ( P < .001) in the MMD/MMS group. No significant differences were found for the radii of the PCA and BA or any artery density and average artery radius measurement in the flow territories ( P > .05). CONCLUSION: His study describes the results of an automatic approach for quantitative characterization of the cerebrovascular system in patients with MMD/MMS with promising preliminary results for quantitative surveillance in pediatric MMD/MMS management.


Assuntos
Doença de Moyamoya , Artérias Cerebrais , Criança , Humanos , Angiografia por Ressonância Magnética , Masculino , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Estudos Retrospectivos
17.
Front Neurol ; 13: 898219, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35775057

RESUMO

Objective: This study sought to determine if individuals with medically refractory migraine headache have volume or diffusion abnormalities on neuroimaging compared to neurotypical individuals. Background: Neuroimaging biomarkers in headache medicine continue to be limited. Early prediction of medically refractory headache and migraine disorders could result in earlier administration of high efficacy therapeutics. Methods: A single-center, retrospective, case control study was performed. All patients were evaluated clinically between 2014 and 2018. Individuals with medically refractory migraine headache (defined by ICDH-3 criteria) without any other chronic medical diseases were enrolled. Patients had to have failed more than two therapeutics and aura was not exclusionary. The initial MRI study for each patient was reviewed. Multiple brain regions were analyzed for volume and apparent diffusion coefficient values. These were compared to 81 neurotypical control patients. Results: A total of 79 patients with medically refractory migraine headache were included and compared to 74 neurotypical controls without headache disorders. Time between clinical diagnosis and neuroimaging was a median of 24 months (IQR: 12.0-37.0). Comparison of individuals with medically refractory migraine headache to controls revealed statistically significant differences in median apparent diffusion coefficient (ADC) in multiple brain subregions (p < 0.001). Post-hoc pair-wise analysis comparing individuals with medically refractory migraine headache to control patients revealed significantly decreased median ADC values for the thalamus, caudate, putamen, pallidum, amygdala, brainstem, and cerebral white matter. No volumetric differences were observed between groups. Conclusions: In individuals with medically refractory MH, ADC changes are measurable in multiple brain structures at an early age, prior to the failure of multiple pharmacologic interventions and the diagnosis of medically refractory MH. This data supports the hypothesis that structural connectivity issues may predispose some patients toward more medically refractory pain disorders such as MH.

19.
Front Neuroinform ; 16: 1056068, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36743439

RESUMO

Introduction: Management of patients with brain metastases is often based on manual lesion detection and segmentation by an expert reader. This is a time- and labor-intensive process, and to that end, this work proposes an end-to-end deep learning segmentation network for a varying number of available MRI available sequences. Methods: We adapt and evaluate a 2.5D and a 3D convolution neural network trained and tested on a retrospective multinational study from two independent centers, in addition, nnU-Net was adapted as a comparative benchmark. Segmentation and detection performance was evaluated by: (1) the dice similarity coefficient, (2) a per-metastases and the average detection sensitivity, and (3) the number of false positives. Results: The 2.5D and 3D models achieved similar results, albeit the 2.5D model had better detection rate, whereas the 3D model had fewer false positive predictions, and nnU-Net had fewest false positives, but with the lowest detection rate. On MRI data from center 1, the 2.5D, 3D, and nnU-Net detected 79%, 71%, and 65% of all metastases; had an average per patient sensitivity of 0.88, 0.84, and 0.76; and had on average 6.2, 3.2, and 1.7 false positive predictions per patient, respectively. For center 2, the 2.5D, 3D, and nnU-Net detected 88%, 86%, and 78% of all metastases; had an average per patient sensitivity of 0.92, 0.91, and 0.85; and had on average 1.0, 0.4, and 0.1 false positive predictions per patient, respectively. Discussion/Conclusion: Our results show that deep learning can yield highly accurate segmentations of brain metastases with few false positives in multinational data, but the accuracy degrades for metastases with an area smaller than 0.4 cm2.

20.
Neuro Oncol ; 24(4): 601-609, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34487172

RESUMO

BACKGROUND: Non-invasive differentiation between schwannomas and neurofibromas is important for appropriate management, preoperative counseling, and surgical planning, but has proven difficult using conventional imaging. The objective of this study was to develop and evaluate machine learning approaches for differentiating peripheral schwannomas from neurofibromas. METHODS: We assembled a cohort of schwannomas and neurofibromas from 3 independent institutions and extracted high-dimensional radiomic features from gadolinium-enhanced, T1-weighted MRI using the PyRadiomics package on Quantitative Imaging Feature Pipeline. Age, sex, neurogenetic syndrome, spontaneous pain, and motor deficit were recorded. We evaluated the performance of 6 radiomics-based classifier models with and without clinical features and compared model performance against human expert evaluators. RESULTS: One hundred and seven schwannomas and 59 neurofibromas were included. The primary models included both clinical and imaging data. The accuracy of the human evaluators (0.765) did not significantly exceed the no-information rate (NIR), whereas the Support Vector Machine (0.929), Logistic Regression (0.929), and Random Forest (0.905) classifiers exceeded the NIR. Using the method of DeLong, the AUCs for the Logistic Regression (AUC = 0.923) and K Nearest Neighbor (AUC = 0.923) classifiers were significantly greater than the human evaluators (AUC = 0.766; p = 0.041). CONCLUSIONS: The radiomics-based classifiers developed here proved to be more accurate and had a higher AUC on the ROC curve than expert human evaluators. This demonstrates that radiomics using routine MRI sequences and clinical features can aid in differentiation of peripheral schwannomas and neurofibromas.


Assuntos
Neurilemoma , Neurofibroma , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Neurilemoma/diagnóstico por imagem , Neurofibroma/diagnóstico por imagem , Estudos Retrospectivos
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