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1.
Artículo en Inglés | MEDLINE | ID: mdl-38713566

RESUMEN

Achieving accurate bladder wall and tumor segmentation from MRI is critical for diagnosing and treating bladder cancer. However, automated segmentation remains challenging due to factors such as comparable density distributions, intricate tumor morphologies, and unclear boundaries. Considering the attributes of bladder MRI images, we propose an efficient multiscale hierarchical hybrid attention with a transformer (MH2AFormer) for bladder cancer and wall segmentation. Specifically, a multiscale hybrid attention and transformer (MHAT) module in the encoder is designed to adaptively extract and aggregate multiscale hybrid feature representations from the input image. In the decoder stage, we devise a multiscale hybrid attention (MHA) module to generate high-quality segmentation results from multiscale hybrid features. Combining these modules enhances the feature representation and guides the model to focus on tumor and wall regions, which helps to solve bladder image segmentation challenges. Moreover, MHAT utilizes the Fast Fourier Transformer with a large kernel (e.g., 224*******224) to model global feature relationships while reducing computational complexity in the encoding stage. The model performance was evaluated on two datasets. As a result, the model achieves relatively best results regarding the intersection over union (IoU) and dice similarity coefficient (DSC) on both datasets (Dataset A: IoU=80.26%, DSC=88.20%; Dataset B: IoU=89.74%, DSC=94.48%). These advantageous outcomes substantiate the practical utility of our approach, highlighting its potential to alleviate the workload of radiologists when applied in clinical settings.

2.
World J Surg Oncol ; 22(1): 89, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600579

RESUMEN

PURPOSE: We aimed to compare the therapeutic effect of radiotherapy (RT) plus systemic therapy (ST) with RT alone in patients with simple brain metastasis (BM) after first-line treatment of limited-stage small cell lung cancer (LS-SCLC). METHODS: The patients were treated at a single center from January 2011 to January 2022. BM only without metastases to other organs was defined as simple BM. The eligible patients were divided into RT alone (monotherapy arm) and RT plus ST (combined therapy arm). Univariate and multivariate Cox proportional hazards analyses were used to examine factors associated with increased risk of extracranial progression. After 1:1 propensity score matching analysis, two groups were compared for extracranial progression-free survival (ePFS), PFS, overall survival (OS), and intracranial PFS (iPFS). RESULTS: 133 patients were identified and 100 were analyzed (monotherapy arm: n = 50, combined therapy arm: n = 50). The ePFS of the combined therapy was significantly longer than that of the monotherapy, with a median ePFS of 13.2 months (95% CI, 6.6-19.8) in combined therapy and 8.2 months (95% CI, 5.7-10.7) in monotherapy (P = 0.04). There were no statistically significant differences in PFS (P = 0.057), OS (P = 0.309), or iPFS (P = 0.448). Multifactorial analysis showed that combined therapy was independently associated with better ePFS compared with monotherapy (HR = 0.617, P = 0.034); more than 5 BMs were associated with worse ePFS compared with 1-5 BMs (HR = 1.808, P = 0.012). CONCLUSIONS: Compared with RT alone, combined therapy improves ePFS in patients with simple BM after first-line treatment of LS-SCLC. Combined therapy and 1-5 BMs reduce the risk of extracranial recurrence.


Asunto(s)
Neoplasias Encefálicas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Humanos , Carcinoma Pulmonar de Células Pequeñas/radioterapia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Estudios Retrospectivos , Neoplasias Encefálicas/radioterapia , Quimioradioterapia
3.
Int J Surg ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38498405

RESUMEN

BACKGROUND: Describe the accurate locations of lymph node recurrence LNR of Chinese patients with postoperative thoracic esophageal squamous cell carcinoma (ESCC) is essential for determining the need for further surveillance protocols and treatments. We aimed to evaluate the patterns of postoperative ESCC and its current risk stratification with LNR. METHODS: This population-based cohort study included a retrospective review of the medical records and image material of patients with ESCC who underwent LNR after radical surgery between January 2013 and September 2022, with a median follow-up time of 5.71 years. Clinical features were extracted from these records, and survival analysis was performed. The primary endpoint was the accurate location and range of LNR according to the nomenclature of the Japanese Society for Esophageal Diseases. The second endpoints was to explore the related factors of recurrence range (RR) and overall survival (OS) . RESULTS: A total of 3268 lymph node regions were recurrence from 1129 patients, with a mean of 2.89 regions per patient. No.104, 106 and 107 was the most common recurrence of thoracic ESCC with an LNR rate higher than 15%. In upper thoracic ESCC, No.105 was a common recurrence site and abdominal lymph node recurrence was rare. In lower thoracic ESCC, retroperitoneal lymph node was a unique regions (15.4%). Anastomotic recurrence is an important recurrence pattern in patients with postoperative esophageal cancer, with an incidence of 24.5%. Rates of lymph node recurrence in range of lymph node dissection was low (13.9%). The median time of LRT was 20.0 (1.5-184.0) months. High range of recurrence was associated with significantly poorer OS in patients. Multiple linear regression analysis identified demonstrated N stage, tumor differentiation, adjuvant radiotherapy and total lymph nodes removed were association with recurrence range for patients. CONCLUSIONS: Supraclavicular and upper mediastinums lymph nodes were common recurrence site for ESCC patients , and careful initial staging and surveillance are needed. Thorough lymph node dissection may reduce the range of regional recurrence.

4.
Med Image Anal ; 94: 103160, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38552528

RESUMEN

Quantitative susceptibility mapping (QSM) is a post-processing technique for deriving tissue magnetic susceptibility distribution from MRI phase measurements. Deep learning (DL) algorithms hold great potential for solving the ill-posed QSM reconstruction problem. However, a significant challenge facing current DL-QSM approaches is their limited adaptability to magnetic dipole field orientation variations during training and testing. In this work, we propose a novel Orientation-Adaptive Latent Feature Editing (OA-LFE) module to learn the encoding of acquisition orientation vectors and seamlessly integrate them into the latent features of deep networks. Importantly, it can be directly Plug-and-Play (PnP) into various existing DL-QSM architectures, enabling reconstructions of QSM from arbitrary magnetic dipole orientations. Its effectiveness is demonstrated by combining the OA-LFE module into our previously proposed phase-to-susceptibility single-step instant QSM (iQSM) network, which was initially tailored for pure-axial acquisitions. The proposed OA-LFE-empowered iQSM, which we refer to as iQSM+, is trained in a simulated-supervised manner on a specially-designed simulation brain dataset. Comprehensive experiments are conducted on simulated and in vivo human brain datasets, encompassing subjects ranging from healthy individuals to those with pathological conditions. These experiments involve various MRI platforms (3T and 7T) and aim to compare our proposed iQSM+ against several established QSM reconstruction frameworks, including the original iQSM. The iQSM+ yields QSM images with significantly improved accuracies and mitigates artifacts, surpassing other state-of-the-art DL-QSM algorithms. The PnP OA-LFE module's versatility was further demonstrated by its successful application to xQSM, a distinct DL-QSM network for dipole inversion. In conclusion, this work introduces a new DL paradigm, allowing researchers to develop innovative QSM methods without requiring a complete overhaul of their existing architectures.


Asunto(s)
Encéfalo , Procesamiento de Imagen Asistido por Computador , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Encéfalo/diagnóstico por imagen , Redes Neurales de la Computación , Mapeo Encefálico/métodos , Imagen por Resonancia Magnética/métodos , Algoritmos
5.
Neuroimage ; 291: 120583, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38554781

RESUMEN

The data-driven approach of supervised learning methods has limited applicability in solving dipole inversion in Quantitative Susceptibility Mapping (QSM) with varying scan parameters across different objects. To address this generalization issue in supervised QSM methods, we propose a novel training-free model-based unsupervised method called MoDIP (Model-based Deep Image Prior). MoDIP comprises a small, untrained network and a Data Fidelity Optimization (DFO) module. The network converges to an interim state, acting as an implicit prior for image regularization, while the optimization process enforces the physical model of QSM dipole inversion. Experimental results demonstrate MoDIP's excellent generalizability in solving QSM dipole inversion across different scan parameters. It exhibits robustness against pathological brain QSM, achieving over 32 % accuracy improvement than supervised deep learning methods. It is also 33 % more computationally efficient and runs 4 times faster than conventional DIP-based approaches, enabling 3D high-resolution image reconstruction in under 4.5 min.


Asunto(s)
Encéfalo , Felodipino , Humanos , Encéfalo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Mapeo Encefálico/métodos , Algoritmos
6.
Artículo en Inglés | MEDLINE | ID: mdl-38181839

RESUMEN

PURPOSE: Neoadjuvant chemoradiotherapy is the recommended treatment for patients with resectable esophageal cancer but is associated with a higher incidence of adverse effects. Given the efficacy of immunotherapy, we propose a chemotherapy-free regimen of neoadjuvant radio-immunotherapy (NRIT) to balance therapeutic efficacy and potential side effects or overtreatment. METHODS AND MATERIALS: In this phase 1b clinical trial, we assessed the safety and efficacy of NRIT in esophageal squamous cell cancer. The enrolled patients received 41.4 Gy of radiation and 4 cycles of 240 mg of toripalimab injection before surgery. The primary endpoint was treatment-related adverse events and the secondary endpoints were pathologic complete response and major pathologic response. Immunohistochemistry and multiplex immunofluorescence staining were used to evaluate the tumor microenvironment before and after neoadjuvant treatment. RESULTS: Of the 22 patients enrolled, 19 underwent R0 surgery. One patient discontinued neoadjuvant immune therapy due to experiencing a grade 3 treatment-related adverse event. Three patients did not undergo surgery due to tumor progression or side effects. Among the patients who underwent surgery, 3 patients experienced serious complications shortly after surgery. Upon pathologic evaluation, the pathologic complete response and major pathologic response rates were 47.4% and 68.4%, respectively. CONCLUSIONS: The NRIT regimen is safe and feasible for patients with esophageal squamous cell cancer.

7.
Phys Med Biol ; 69(2)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38091612

RESUMEN

Objective. Bladder cancer is a common malignant urinary carcinoma, with muscle-invasive and non-muscle-invasive as its two major subtypes. This paper aims to achieve automated bladder cancer invasiveness localization and classification based on MRI.Approach. Different from previous efforts that segment bladder wall and tumor, we propose a novel end-to-end multi-scale multi-task spatial feature encoder network (MM-SFENet) for locating and classifying bladder cancer, according to the classification criteria of the spatial relationship between the tumor and bladder wall. First, we built a backbone with residual blocks to distinguish bladder wall and tumor; then, a spatial feature encoder is designed to encode the multi-level features of the backbone to learn the criteria.Main Results. We substitute Smooth-L1 Loss with IoU Loss for multi-task learning, to improve the accuracy of the classification task. By learning two datasets collected from bladder cancer patients at the hospital, the mAP, IoU, Acc, Sen and Spec are used as the evaluation metrics. The experimental result could reach 93.34%, 83.16%, 85.65%, 81.51%, 89.23% on test set1 and 80.21%, 75.43%, 79.52%, 71.87%, 77.86% on test set2.Significance. The experimental result demonstrates the effectiveness of the proposed MM-SFENet on the localization and classification of bladder cancer. It may provide an effective supplementary diagnosis method for bladder cancer staging.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Vejiga Urinaria/patología
8.
Int J Surg ; 110(2): 956-964, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37995095

RESUMEN

BACKGROUND: There is no standard management for small cell esophageal carcinoma (SCEC). The purpose of this multicenter, retrospective study (ChiSCER) was to investigate the treatment, outcomes, and risk factors impacting survival endpoints in patients with limited-stage SCEC (LS-SCEC). MATERIALS AND METHODS: Consecutive patients with LS-SCEC from 14 institutions between 2000 and 2020 in China were enrolled. Survival curves were constructed using the Kaplan-Meier method and compared using a log-rank test. Univariate and multivariate Cox regression models and propensity score matching (PSM) analysis were adopted in the prognostic analysis. Results were reported as hazard ratio (HR), 95% confidence interval (CI), and P value. Statistical significance was set as P value <0.05 in a two-tailed test. RESULTS: Among 458 LS-SCEC patients, the median age was 63 [interquartile range (IQR), 57-68] years, and 318 (69%) were males. Eighty-four (18%), 167 (36%), and 207 (45%) patients received chemotherapy (CT) alone, CT plus definitive radiotherapy (CT+RT), and CT plus radical surgery (CT+S), respectively. With a median follow-up time of 58.7 (95% CI 48.9-68.6) months, the median overall survival (OS) and 3-year OS rate for all patients 24.3 (95% CI 21.6-27) months and 37.3% (95% CI 32.8-42.5%), respectively. Multivariate analysis indicated that treatment modes, Karnofsky performance status (KPS), TNM stage, and CT cycle were independent prognostic factors for OS ( P <0.05). Compared with CT alone, patients treated with CT+RT (HR 0.57, 95% CI 0.41-0.8, P =0.001) or CT+S (HR 0.59, 95% CI 0.42-0.82, P =0.002) had an improved OS, with no significant survival differences between CT+S and CT+RT groups after multivariate and PSM analyses ( P >0.05). Subgroup analysis indicated that compared with CT+RT, patients with tumor location at lower 1/3 (HR 0.59, 95% CI 0.37-0.93, P =0.03) or tumor length >5 cm (HR 0.52, 95% CI 0.3-0.9, P =0.02) could obtain significant OS benefit from CT+S. Patients with tumor location at middle 1/3 (HR 1.55, 95% CI 1.03-2.36, P =0.04) or tumor length ≤5 cm (HR 1.49, 95% CI 1.02-2.17, P =0.04) favored CT+RT. Distant metastasis accounted for 73.7% of all treatment failures after multidisciplinary treatments. CONCLUSION: Surgery and RT were equally effective local therapies for patients with LS-SCEC. The personalized decision of local therapy should be made after comprehensive considerations on tumor location, length, comorbidities, and organ preservation.


Asunto(s)
Carcinoma de Células Pequeñas , Neoplasias Esofágicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma de Células Pequeñas/patología , Estudios de Cohortes , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirugía , Neoplasias Esofágicas/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos
9.
J Cancer Res Ther ; 19(6): 1582-1588, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38156925

RESUMEN

OBJECTIVE: This study was conducted to determine whether higher doses of intensity-modulated radiotherapy (IMRT) could improve the survival rate in patients of cervical esophageal squamous cell carcinoma (CESCC), and lead to more severe treatment-related toxicity. METHODS: The clinical records of stage I-IVA CESCC patients treated with definitive chemoradiotherapy (CRT) using IMRT between January 2013 and June 2018 were retrospectively analyzed. The patients in the high-dose (HD) group received ≥60 Gy and those in the standard-dose group received <60 Gy. A propensity score matching (PSM) was applied to balance the confounding factors between both groups. The primary endpoint was over-survival (OS). progression-free survival (PFS), loco-regional control (LRC), and treatment-related toxicity were also evaluated. RESULTS: A total of 136 patients with CESCC were included. Patients with N1-3 nodal and stages III-IVA of the disease (P < 0.05) were included in the HD group. The differences in the OS, PFS, and LRC between the two groups were not statistically significant (P = 0.350, 0.063, and 0.099, respectively). After PSM, significantly longer PFS and LRC were observed in the HD group. The difference in OS between the two groups was not statistically significant. There was no significant difference in the incidence of treatment-related toxicity between the two groups. CONCLUSIONS: The results of this PSM analysis suggested that higher doses may improve PFS and LRC for CESCC patients receiving CRT using OMRT, but do not demonstrate any statistically significant advantage in improving OS.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Radioterapia de Intensidad Modulada , Humanos , Carcinoma de Células Escamosas de Esófago/terapia , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Neoplasias Esofágicas/radioterapia , Estudios Retrospectivos , Puntaje de Propensión , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Dosis de Radiación , Células Epiteliales/patología
10.
Front Neurosci ; 17: 1286361, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37786813
11.
Front Immunol ; 14: 1193394, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37325650

RESUMEN

Background: Esophageal cancer (EC) is an aggressive neoplasm of the gastrointestinal tract that is usually treated with a combination of chemotherapy, radiotherapy (RT), and/or surgery, according to disease status. Despite the availability of multimodal therapeutic strategies, local recurrence is frequently observed. However, there is no standard treatment or promising therapeutic approach for local recurrence or metastatic esophageal carcinoma after the RT. This study tended to investigate the efficacy and safety of sintilimab maintenance after concurrent chemoradiotherapy (CCRT) for local/regional recurrent esophageal squamous carcinoma. Methods: This study was a single-arm, phase Ib/II trial conducted in a single site in China. Patients previously radically treated (surgery or CCRT), histologically confirmed, local or regional recurrence esophageal squamous carcinoma, qualified for the study design, were treated with 25-28 times radiotherapy plus raltitrexed once every 3 weeks for up to two cycles. Patients who have not progressed after CCRT received sintilimab as maintenance once every 3 weeks up to 1 year. Primary endpoints were overall survival (OS) and safety. Secondary endpoints were progression-free survival (PFS), objective response rate (ORR), and duration of response (DOR). Results: Between September 2019 and March 2022, in a total of 36 enrolled patients, 34 pts completed CCRT. Three patients excluded due to violation of the exclusion criteria (1 pt) and consent withdrawal (2 pts). Finally, 33 pts were included in the final analysis, in which 3 pts had disease progression, and the remaining 30 entered maintenance therapy with sintilimab. The median follow-up time was 12.3 months. Median OS was 20.6 months (95%CI 10.5-NA) and the 1-year OS rate was 64%. Median PFS was 11.5 months (95%CI 5.29-21.3) and the 1-year PFS rate was 43.6%. The ORR was 63.6% (95%CI 44.6-77.8), including 2 cases of CR and 19 cases of PR. The DCR was 19.9%, the median DOR was 19.5 months, and the median TTR was 2.4 months. The rate of any grade TRAEs was 96.7%; ≥Grade 3 TRAE was 23.4%. The incidence of immune-related AE was 60%, most of which were grade 1-2, and only one case of thyroid-stimulating hormone increased was irAE with grade 3 or above. Conclusion: Sintilimab has shown promising clinical efficacy and a manageable safety profile as maintenance therapy after CCRT for local/regional recurrent esophageal squamous carcinoma. In addition, further confirmation from a large-scale real-world study is still needed.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Escamosas/patología , Quimioradioterapia , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/terapia , Carcinoma de Células Escamosas de Esófago/patología
12.
Front Neurol ; 14: 1148878, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37251219

RESUMEN

Purpose: This study aims to investigate the glymphatic system activity changes in patients with mild traumatic brain injury (mTBI), particularly in MRI-negative patients, using analysis along the perivascular space (ALPS) technology. Methods: A total of 161 mTBI patients (age: 15-92 years old) and 28 healthy controls (age: 15-84 years old) were included in this retrospective study. The mTBI patients were divided into MRI-negative and MRI-positive groups. ALPS index was calculated automatically using whole-brain T1-MPRAGE imaging and diffusion tensor imaging. The Student's t and chi-squared tests were performed to compare the ALPS index, age, gender, course of disease, and Glasgow Coma Scale (GCS) score between groups. Correlations among ALPS index, age, course of disease and GCS score were computed using Spearman's correlation analysis. Results: Increased activity of the glymphatic system was suggested in mTBI patients based on ALPS index analysis, including the MRI-negative patients. There was a significant negative correlation between the ALPS index and age. In addition, a weak positive correlation between the ALPS index and course of disease was also observed. On the contrary, there was no significant correlation between the ALPS index and sex nor between the ALPS index and GCS score. Conclusion: Our study demonstrated that the activity level of the glymphatic system was enhanced in mTBI patients, even when their brain MRI scans were negative. These findings may provide novel insights for understanding the pathophysiology of mild TBI.

13.
Magn Reson Med ; 90(3): 963-977, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37125656

RESUMEN

PURPOSE: MRI is increasingly utilized for image-guided radiotherapy due to its outstanding soft-tissue contrast and lack of ionizing radiation. However, geometric distortions caused by gradient nonlinearities (GNLs) limit anatomical accuracy, potentially compromising the quality of tumor treatments. In addition, slow MR acquisition and reconstruction limit the potential for effective image guidance. Here, we demonstrate a deep learning-based method that rapidly reconstructs distortion-corrected images from raw k-space data for MR-guided radiotherapy applications. METHODS: We leverage recent advances in interpretable unrolling networks to develop a Distortion-Corrected Reconstruction Network (DCReconNet) that applies convolutional neural networks (CNNs) to learn effective regularizations and nonuniform fast Fourier transforms for GNL-encoding. DCReconNet was trained on a public MR brain dataset from 11 healthy volunteers for fully sampled and accelerated techniques, including parallel imaging (PI) and compressed sensing (CS). The performance of DCReconNet was tested on phantom, brain, pelvis, and lung images acquired on a 1.0T MRI-Linac. The DCReconNet, CS-, PI-and UNet-based reconstructed image quality was measured by structural similarity (SSIM) and RMS error (RMSE) for numerical comparisons. The computation time and residual distortion for each method were also reported. RESULTS: Imaging results demonstrated that DCReconNet better preserves image structures compared to CS- and PI-based reconstruction methods. DCReconNet resulted in the highest SSIM (0.95 median value) and lowest RMSE (<0.04) on simulated brain images with four times acceleration. DCReconNet is over 10-times faster than iterative, regularized reconstruction methods. CONCLUSIONS: DCReconNet provides fast and geometrically accurate image reconstruction and has the potential for MRI-guided radiotherapy applications.


Asunto(s)
Aprendizaje Profundo , Radioterapia Guiada por Imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Pulmón/patología , Humanos
14.
Neuroimage ; 267: 119842, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36586542

RESUMEN

Deep neural networks have demonstrated great potential in solving dipole inversion for Quantitative Susceptibility Mapping (QSM). However, the performances of most existing deep learning methods drastically degrade with mismatched sequence parameters such as acquisition orientation and spatial resolution. We propose an end-to-end AFfine Transformation Edited and Refined (AFTER) deep neural network for QSM, which is robust against arbitrary acquisition orientation and spatial resolution up to 0.6 mm isotropic at the finest. The AFTER-QSM neural network starts with a forward affine transformation layer, followed by a Unet for dipole inversion, then an inverse affine transformation layer, followed by a Residual Dense Network (RDN) for QSM refinement. Simulation and in-vivo experiments demonstrated that the proposed AFTER-QSM network architecture had excellent generalizability. It can successfully reconstruct susceptibility maps from highly oblique and anisotropic scans, leading to the best image quality assessments in simulation tests and suppressed streaking artifacts and noise levels for in-vivo experiments compared with other methods. Furthermore, ablation studies showed that the RDN refinement network significantly reduced image blurring and susceptibility underestimation due to affine transformations. In addition, the AFTER-QSM network substantially shortened the reconstruction time from minutes using conventional methods to only a few seconds.


Asunto(s)
Encéfalo , Procesamiento de Imagen Asistido por Computador , Humanos , Encéfalo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación , Simulación por Computador , Algoritmos , Mapeo Encefálico/métodos
15.
Z Med Phys ; 33(4): 578-590, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36064695

RESUMEN

INTRODUCTION: Background field removal (BFR) is a critical step required for successful quantitative susceptibility mapping (QSM). However, eliminating the background field in brains containing significant susceptibility sources, such as intracranial hemorrhages, is challenging due to the relatively large scale of the field induced by these pathological susceptibility sources. METHOD: This study proposes a new deep learning-based method, BFRnet, to remove the background field in healthy and hemorrhagic subjects. The network is built with the dual-frequency octave convolutions on the U-net architecture, trained with synthetic field maps containing significant susceptibility sources. The BFRnet method is compared with three conventional BFR methods and one previous deep learning method using simulated and in vivo brains from 4 healthy and 2 hemorrhagic subjects. Robustness against acquisition field-of-view (FOV) orientation and brain masking are also investigated. RESULTS: For both simulation and in vivo experiments, BFRnet led to the best visually appealing results in the local field and QSM results with the minimum contrast loss and the most accurate hemorrhage susceptibility measurements among all five methods. In addition, BFRnet produced the most consistent local field and susceptibility maps between different sizes of brain masks, while conventional methods depend drastically on precise brain extraction and further brain edge erosions. It is also observed that BFRnet performed the best among all BFR methods for acquisition FOVs oblique to the main magnetic field. CONCLUSION: The proposed BFRnet improved the accuracy of local field reconstruction in the hemorrhagic subjects compared with conventional BFR algorithms. The BFRnet method was effective for acquisitions of tilted orientations and retained whole brains without edge erosion as often required by traditional BFR methods.


Asunto(s)
Aprendizaje Profundo , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Cabeza , Mapeo Encefálico/métodos , Algoritmos
16.
Can J Neurol Sci ; 50(6): 853-860, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36351571

RESUMEN

BACKGROUND: Quantitative susceptibility mapping (QSM) demonstrates elevated iron content in Parkinson's disease (PD) patients within the basal ganglia, though it has infrequently been studied in relation to gait difficulties including freezing of gait (FOG). Our purpose was to relate QSM of basal ganglia and extra-basal ganglia structures with qualitative and quantitative gait measures in PD. METHODS: This case-control study included PD and cognitively unimpaired (CU) participants from the Comprehensive Assessment of Neurodegeneration and Dementia study. Whole brain QSM was acquired at 3T. Region of interests (ROIs) were drawn blinded manually in the caudate nucleus, putamen, globus pallidus, pulvinar nucleus of the thalamus, red nucleus, substantia nigra, and dentate nucleus. Susceptibilities of ROIs were compared between PD and CU. Items from the FOG questionnaire and quantitative gait measures from PD participants were compared to susceptibilities. RESULTS: Twenty-nine participants with PD and 27 CU participants were included. There was no difference in susceptibility values in any ROI when comparing CU versus PD (p > 0.05 for all). PD participants with gait impairment (n = 23) had significantly higher susceptibility in the putamen (p = 0.008), red nucleus (p = 0.01), and caudate nucleus (p = 0.03) compared to those without gait impairment (n = 6). PD participants with FOG (n = 12) had significantly higher susceptibility in the globus pallidus (p = 0.03) compared to those without FOG (n = 17). Among quantitative gait measures, only stride time variability was significantly different between those with and without FOG (p = 0.04). CONCLUSION: Susceptibilities in basal ganglia and extra-basal ganglia structures are related to qualitative measures of gait impairment and FOG in PD.

17.
Cancer Immunol Immunother ; 72(3): 733-742, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36194288

RESUMEN

BACKGROUND: The role of tumor-associated macrophages (TAMs) in glioblastoma (GBM) disease progression has received increasing attention. Recent advances have shown that TAMs can be re-programmed to exert a pro-inflammatory, anti-tumor effect to control GBMs. However, imaging methods capable of differentiating tumor progression from immunotherapy treatment effects have been lacking, making timely assessment of treatment response difficult. We showed that tracking monocytes using iron oxide nanoparticle (USPIO) with MRI can be a sensitive imaging method to detect therapy response directed at the innate immune system. METHODS: We implanted syngeneic mouse glioma stem cells into C57/BL6 mice and treated the animals with either niacin (a stimulator of innate immunity) or vehicle. Animals were imaged using an anatomical MRI sequence, R2* mapping, and quantitative susceptibility mapping (QSM) before and after USPIO injection. RESULTS: Compared to vehicles, niacin-treated animals showed significantly higher susceptibility and R2*, representing USPIO and monocyte infiltration into the tumor. We observed a significant reduction in tumor size in the niacin-treated group 7 days later. We validated our MRI results with flow cytometry and immunofluoresence, which showed that niacin decreased pro-inflammatory Ly6C high monocytes in the blood but increased CD16/32 pro-inflammatory macrophages within the tumor, consistent with migration of these pro-inflammatory innate immune cells from the blood to the tumor. CONCLUSION: MRI with USPIO injection can detect therapeutic responses of innate immune stimulating agents before changes in tumor size have occurred, providing a potential complementary imaging technique to monitor cancer immunotherapies. MANUSCRIPT HIGHLIGHT: We show that iron oxide nanoparticles (USPIOs) can be used to label innate immune cells and detect the trafficking of pro-inflammatory monocytes into the glioblastoma. This preceded changes in tumor size, making it a more sensitive imaging technique.


Asunto(s)
Glioblastoma , Glioma , Niacina , Ratones , Animales , Monocitos/patología , Glioma/patología , Modelos Animales , Imagen por Resonancia Magnética/métodos
18.
Aging Male ; 25(1): 281-292, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36382930

RESUMEN

OBJECTIVE: The aim of the meta-analysis was to explore effects of resistance exercise (RE) on body composition and physical function in patients with prostate cancer (PCa). DATA SOURCES: We searched the electronic databases of Pubmed, Embase, Cochrane, and web of science. Published studies have been collected from these databases. Search terms include resistance training, strength training, RE, androgen suppression therapy, androgen deprivation therapy and PCa, with a deadline of 31 March 2022. MAIN RESULTS: These studies showed significant improvements of body composition(Lean body mass MD: 1.12 95% CI [0.48, 1.76], p < 0.01; Body fat rate MD: -1.12 95% CI [-1.99,-0.24], p < 0.05; Appendicular skeletal mass MD: 0.74 95% CI [0.45, 1.03], p < 0.01) and physical function (leg press MD: 77.95 95% CI [38.90, 117.00], p < 0.01; stair climb MD:-0.30 95% CI [-0.49, -0.12], p < 0.01). In addition, the improvement of Body fat mass (MD: -0.21 95% CI [-0.79, 0.37], p > 0.05), 400 m walk (MD: -21.74 95% CI [-45.53, 2.05], p > 0.05) and times up and go (MD: -0.50 95% CI [-1.03, 0.03], p > 0.05) were not obvious. Subgroup analyses showed that RE for ≥ 6 months (compared with RE intervention for < 6 months) and starting exercise immediately after androgen deprivation therapy (ADT) (compared with delayed exercise after ADT) resulted in more significant improvements in body composition. Furthermore, the results showed that the exercise intensity of 8-12 RM significantly improved body composition. CONCLUSIONS: RE seems to be a promising approach in order to improve body composition and physical function in PCa patients to offset their treatment-related side effects. RE should be used as a means of rehabilitation and care for PCa. Starting exercise immediately after ADT and extending exercise time while choosing the right intensity can better improve the patients' body composition and function. REGISTRATION NUMBER: INPLASY202280019.


Asunto(s)
Neoplasias de la Próstata , Entrenamiento de Fuerza , Masculino , Humanos , Antagonistas de Andrógenos/efectos adversos , Neoplasias de la Próstata/tratamiento farmacológico , Andrógenos/uso terapéutico , Composición Corporal , Terapia por Ejercicio/métodos
19.
Front Oncol ; 12: 841771, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35992838

RESUMEN

Purpose: To compare the difference between magnetic resonance imaging (MRI) and computed tomography (CT) in delineating the target area of lung cancer with atelectasis. Method: A retrospective analysis was performed on 15 patients with lung cancer accompanied by atelectasis. All positioning images were transferred to Eclipse treatment planning systems (TPSs). Six MRI sequences (T1WI, T1WI+C, T1WI+C Delay, T1WI+C 10 minutes, T2WI, DWI) were registered with positioning CT. Five radiation oncologists delineated the tumor boundary to obtain the gross tumor volume (GTV). Conformity index (CI) and dice coefficient (DC) were used to measure differences among observers. Results: The differences in delineation mean volumes, CI, and DC among CT and MRIs were significant. Multiple comparisons were made between MRI sequences and CT. Among them, DWI, T2WI, and T1WI+C 10 minutes sequences were statistically significant with CT in mean volumes, DC, and CI. The mean volume of DWI, T2WI, and T1WI+C 10 minutes sequence in the target area is significantly smaller than that on the CT sequence, but the consistency is higher than that of CT sequences. Conclusions: The recognition of atelectasis by MRI was better than that by CT, which could reduce interobserver variability of primary tumor delineation in lung cancer with atelectasis. Among them, DWI, T2WI, T1WI+C 10 minutes may be a better choice to improve the GTV delineation of lung cancer patients with atelectasis.

20.
Alcohol Clin Exp Res ; 46(10): 1797-1807, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36016464

RESUMEN

BACKGROUND: Prenatal alcohol exposure (PAE) can negatively affect brain development thereby increasing the risk of cognitive deficits, behavioral challenges, and mental health problems. Brain iron is important for a number of physiological processes for healthy brain development. Animal studies show that PAE reduced brain iron; however, this has not been investigated in human children with PAE. METHODS: We studied 20 children and adolescents with PAE and 44 unexposed children and adolescents aged 7.5 to 15 years. All children underwent quantitative susceptibility mapping and T1-weighted magnetic resonance imaging scans. Susceptibility and volume measurements of the caudate, putamen, pallidum, thalamus, amygdala, hippocampus, and nucleus accumbens were extracted using FreeSurfer. ANCOVAs were used to compare volume and susceptibility between groups for each region of interest, controlling for age and gender. For structures where susceptibility differed by group, we also tested for an association between intelligence quotient (IQ) and susceptibility. RESULTS: There were no significant group differences in susceptibility after multiple comparison correction, though the PAE group had higher susceptibility in the thalamus compared to unexposed participants before correction (p = 0.032, q = 0.230). There was no association between IQ and thalamus susceptibility. The PAE group had significantly lower volume in the bilateral caudate, bilateral pallidum, and left putamen. CONCLUSIONS: These findings suggest susceptibility may be altered in children and adolescents with PAE, though more research is needed. Volume reductions are consistent with previous literature and likely underlie cognitive and behavioral deficits associated with PAE.


Asunto(s)
Efectos Tardíos de la Exposición Prenatal , Niño , Animales , Humanos , Adolescente , Femenino , Embarazo , Efectos Tardíos de la Exposición Prenatal/psicología , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Pruebas de Inteligencia , Hierro
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