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1.
J Appl Clin Med Phys ; 24(10): e14078, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37335543

RESUMO

PURPOSE: To investigate the dosimetry effects of different gating strategies in cine magnetic resonance imaging (MRI)-guided breath-hold pancreatic cancer radiotherapy. METHODS: Two cine MRI-based gating strategies were investigated: a tumor contour-based gating strategy at a gating threshold of 0-5% and a tumor displacement-based gating strategy at a gating threshold of 3-5 mm. The cine MRI videos were obtained from 17 pancreatic cancer patients who received MRI-guided radiation therapy. We calculated the tumor displacement in each cine MR frame that satisfied the gating threshold and obtained the proportion of frames with different displacements. We generated IMRT and VMAT plans using a 33 Gy prescription, and motion plans were generated by adding up all isocenter-shift plans corresponding to different tumor displacements. The dose parameters of GTV, PTV, and organs at risk (OAR) were compared between the original and motion plans. RESULTS: In both gating strategies, the difference was significant in PTV coverage but not in GTV coverage between the original and motion plans. OAR dose parameters deteriorate with increasing gating threshold. The beam duty cycle increased from 19.5±14.3% (median 18.0%) to 60.8±15.6% (61.1%) for gating thresholds from 0% to 5% in tumor contour-based gating and from 51.7±11.5% (49.7%) to 67.3±12.4% (67.1%) for gating thresholds from 3 to 5 mm in tumor displacement-based gating. CONCLUSION: In tumor contour-based gating strategy, the dose delivery accuracy deteriorates while the dose delivery efficiency improves with increasing gating thresholds. To ensure treatment efficiency, the gating threshold might be no less than 3%. A threshold up to 5% may be acceptable in terms of the GTV coverage. The displacement-based gating strategy may serve as a potential alternative to the tumor contour based gating strategy, in which the gating threshold of approximately 4 mm might be a good choice for reasonably balancing the dose delivery accuracy and efficiency.


Assuntos
Neoplasias Pancreáticas , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Humanos , Neoplasias Pancreáticas/radioterapia , Suspensão da Respiração , Imageamento por Ressonância Magnética/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Radioterapia Guiada por Imagem/métodos , Neoplasias Pancreáticas
2.
PeerJ ; 12: e17499, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846752

RESUMO

Objective: The objective of this study was to delineate the profile of peripheral blood lymphocytic indices in patients afflicted with high-grade squamous intraepithelial lesions (HSIL) and cervical neoplasms, and to elucidate the correlation of these hematologic markers with the clinicopathological spectra in individuals diagnosed with cervical carcinoma. Methods: We adopted a retrospective case-control modality for this investigation. An aggregate of 39 HSIL patients and 42 cervical carcinoma patients, who were treated in our facility from July 2020 to September 2023, were meticulously selected. Each case of cervical malignancy was confirmed through rigorous histopathological scrutiny. Concomitantly, 31 healthy female individuals, who underwent prophylactic health evaluations during the corresponding timeframe, were enlisted as the baseline control group. We systematically gathered and analyzed clinical demographics, as well as the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), from peripheral blood samples. Pearson's correlation coefficient was deployed to dissect the interrelation between peripheral NLR and PLR concentrations and the clinicopathological features in the cervical cancer group. Results: Inter-group comparative analysis unveiled statistically substantial variances in the PLR and NLR values among the tripartite clusters (F = 36.941, 14.998, P < 0.001, respectively). Although discrepancy in NLR (P = 0.061) and PLR (P = 0.759) measures between the groups of cervical carcinoma and HSIL was not statistically appreciable, these indices were markedly elevated in the cervical carcinoma faction as juxtaposed with the normative control group (t = 5.094, 5.927; P < 0.001 for both parameters). A discernible gradation in peripheral blood PLR and NLR concentrations was noted when stratified by clinical stage and the profundity of myometrial invasion in cervical cancer subjects (P < 0.001). The correlation matrix demonstrated a positive liaison between peripheral blood PLR and the clinical gradation, as well as the invasiveness of the neoplastic cells into the muscularis propria (P < 0.05); a similar trend was observed with the NLR values (P < 0.05). Conclusion: Augmented NLR and PLR levels in peripheral blood specimens are indicative of HSIL and cervical malignancy. These hematological parameters exhibit a pronounced interconnection with clinical staging and muscular wall penetration depth, serving as potential discriminative biomarkers for the diagnosis and prognosis of cervical cancer.


Assuntos
Neutrófilos , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/sangue , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/imunologia , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Neutrófilos/patologia , Neutrófilos/imunologia , Estudos de Casos e Controles , Linfócitos/patologia , Linfócitos/imunologia , Lesões Intraepiteliais Escamosas/patologia , Lesões Intraepiteliais Escamosas/sangue , Contagem de Linfócitos , Plaquetas/patologia , Plaquetas/imunologia , Lesões Intraepiteliais Escamosas Cervicais/sangue , Lesões Intraepiteliais Escamosas Cervicais/patologia , Lesões Intraepiteliais Escamosas Cervicais/imunologia , Lesões Intraepiteliais Escamosas Cervicais/diagnóstico
3.
J Vasc Access ; : 11297298231209382, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37997017

RESUMO

BACKGROUND: Ultrasound guidance for radial arterial cannulation is currently considered a best practice approach despite its clear advantages over the blind and palpation technique, the success rate is related to several factors, including clinician's experience and technical ability. The study aimed to explore the use of a novel track guidance ultrasound that may increase the success rate of radial arterial cannulation. METHODS: A randomized controlled trial was conducted, in which 80 adults scheduled for elective surgery requiring radial arterial cannulation were recruited and randomly assigned to either the experimental group, which utilized novel track ultrasound guidance (group T, n = 40), or the control group, which utilized traditional ultrasound guidance (group U, n = 40). The novel track guidance ultrasound comprises a positioning track and a guided track. The radial artery could be positioned at the center of the positional track on the ultrasound image, and the direction and angle of needle are fixed and toward the center of the positioning track. The primary endpoint of the study was the first-pass cannulation success rate, while the secondary endpoints included the failure rate of cannulation, the number of radial artery punctures, the time of cannulation, and the incidence of hematoma. RESULTS: The success rate of cannulation at the first attempt in group T (35 of 40 (87.5%)) was significantly higher than that in group U (23 of 40 (57.5%); p = 0.003). Although seven patients in Group U (7 of 40 (17.5%)) experienced failed cannulation compared to one in Group T (1 of 40 (2.5%)), the difference in failure rate between the two groups did not reach statistical significance (p = 0.06). CONCLUSIONS: The implementation of novel track ultrasound guidance has demonstrated a notable improvement in the success rates at the first attempt while reducing the frequency of punctures and cannulation times.

4.
Med Phys ; 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38043123

RESUMO

BACKGROUND: Cine magnetic resonance (MR) images have been used for real-time MR guided radiation therapy (MRgRT). However, the onboard MR systems with low-field strength face the problem of limited image quality. PURPOSE: To improve the quality of cine MR images in MRgRT using prior image information provided by the patient planning and positioning MR images. METHODS: This study employed MR images from 18 pancreatic cancer patients who received MR-guided stereotactic body radiation therapy. Planning 3D MR images were acquired during the patient simulation, and positioning 3D MR images and 2D sagittal cine MR images were acquired before and during the beam delivery, respectively. A deep learning-based framework consisting of two cycle generative adversarial networks (CycleGAN), Denoising CycleGAN and Enhancement CycleGAN, was developed to establish the mapping between the 3D and 2D MR images. The Denoising CycleGAN was trained to first denoise the cine images using the time domain cine image series, and the Enhancement CycleGAN was trained to enhance the spatial resolution and contrast by taking advantage of the prior image information from the planning and positioning images. The denoising performance was assessed by signal-to-noise ratio (SNR), structural similarity index measure, peak SNR, blind/reference-less image spatial quality evaluator (BRISQUE), natural image quality evaluator, and perception-based image quality evaluator scores. The quality enhancement performance was assessed by the BRISQUE and physician visual scores. In addition, the target contouring was evaluated on the original and processed images. RESULTS: Significant differences were found for all evaluation metrics after Denoising CycleGAN processing. The BRISQUE and visual scores were also significantly improved after sequential Denoising and Enhancement CycleGAN processing. In target contouring evaluation, Dice similarity coefficient, centroid distance, Hausdorff distance, and average surface distance values were significantly improved on the enhanced images. The whole processing time was within 20 ms for a typical input image size of 512 × 512. CONCLUSION: Taking advantage of the prior high-quality positioning and planning MR images, the deep learning-based framework enhanced the cine MR image quality significantly, leading to improved accuracy in automatic target contouring. With the merits of both high computational efficiency and considerable image quality enhancement, the proposed method may hold important clinical implication for real-time MRgRT.

5.
Med Phys ; 49(10): 6334-6345, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35950934

RESUMO

BACKGROUND: Radiotherapy to tumors in the abdomen is challenging because of the significant organ movement and tissue deformation caused by respiration. PURPOSE: A motion management strategy that integrated ultrasound (US) imaging with abdominal compression was developed and evaluated, where US was used to real-time monitor organ motion after abdominal compression. METHODS: A device that combined a US imaging system and an abdominal compression plate (ACP) was developed. Twenty-one healthy volunteers were involved to evaluate the motion management efficacy. Each volunteer was immobilized on a flat bench by the device. Abdominal US data were successively collected with and without ACP compression, and experiments were repeated three times to verify the imaging reproducibility. A template matching algorithm based on normalized cross-correlation was implemented to track the targets (vessels in the liver, pancreas, and stomach) automatically. The matching algorithm was validated by comparing with the manual references. Automatic tracking was judged as failed if the center-of-mass difference from manual tracking was beyond a failure threshold. Based on the locations obtained through the template matching algorithm, the motion correlation between liver and pancreas/stomach was investigated using the Pearson correlation test. Paired Student's t-test was used to analyze the difference between the results without and with ACP compression. RESULTS: The liver motion amplitude over all 21 volunteers was significantly (p < 0.001) reduced from 14.9 ± 5.5/3.4 ± 1.8 mm in superior-inferior (SI)/anterior-posterior (AP) direction before ACP compression to 7.3 ± 1.5/1.6 ± 0.7 mm after ACP compression. The mean liver motion standard deviation before compression was on average 2.8/1.4 mm in SI/AP direction and was significantly (p < 0.001) reduced to 0.9/0.4 mm after compression. The failure rates of automatic tracking for liver, pancreas, and stomach were reduced for failure thresholds of 1-5 mm after applying ACP. The Pearson correlation coefficients between liver and pancreas/stomach were 0.98/0.97 without ACP and 0.96/0.94 with ACP in the SI direction and were 0.68/0.68 and 0.43/0.42 in the AP direction. The motion prediction errors for pancreas/stomach with ACP have significantly (p < 0.001) reduced to 0.45 ± 0.36/0.52 ± 0.43 mm from 0.69 ± 0.56/0.71 ± 0.66 mm without ACP in the SI direction, and to 0.38 ± 0.33/0.39 ± 0.27 mm from 0.44 ± 0.35/0.61 ± 0.59 mm in the AP direction. CONCLUSIONS: The proposed strategy that combines real-time US imaging and abdominal compression has the potential to reduce the abdominal organ motion while improving both target tracking reliability and motion reproducibility. Furthermore, the observed correlation between liver and pancreas/stomach motion indicates the possibility of indirect pancreas/stomach tracking using liver markers as tracking surrogates. The strategy is expected to provide an alternative for respiratory motion management in the radiation treatment of abdominal tumors.


Assuntos
Abdome , Respiração , Abdome/diagnóstico por imagem , Humanos , Movimento (Física) , Movimento , Reprodutibilidade dos Testes , Ultrassonografia
6.
Front Endocrinol (Lausanne) ; 13: 963191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36176460

RESUMO

Background and purpose: Growth factor receptor-bound protein 2(GRB2), a bridging protein. An animal study showed that downregulation of GRB2 inhibited the activation of PI3K/AKT/NF-kB pathway which improved lipid accumulation and inflammatory infiltration in rats with atherosclerosis (AS), resulting in an anti-AS effect. This was the first study to investigate blood GRB2 levels in type 2 diabetes mellitus(T2DM) patients with carotid atherosclerosis (CAS), exploring its relationship with various metabolic indicators, and further, examining whether GRB2 has an AS effect in patients with T2DM. Methods: A total of 203 participants were recruited in the study, including 69 T2DM patients without CAS (T2DM group), 67 T2DM patients with CAS (CAS group), and 67 in the age-sex-matched healthy subjects (Control group). Serum GRB2 levels were measured using enzyme-linked immunosorbent assay (ELISA) in 203 subjects who had received carotid ultrasonography. In addition, cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), glycosylated hemoglobin (HBA1c), fasting insulin (FINS), hypersensitive C-reactive protein (Hs-CRP), and Interleukin 6 (IL-6) were also tested. The correlation between serum GRB2 levels and other indexes was analyzed. Finally, we analyzed the risk factors affecting carotid intima-media thickness (CIMT) in T2DM patients. Results: Serum GRB2 levels were increased in the T2DM group than in the control group, and further elevated in the CAS group (median 3.05 vs 4.40 vs 7.09 ng/ml, P<0.001). Spearman correlation analysis showed that GRB2 concentrations were negatively correlated with HDL-C, and positively associated with duration of diabetes, waist-to-hip ratio (WHR), TC, HBA1c, FPG, FINS, homeostasis model assessment-insulin resistance index (HOMA-IR), Hs-CRP, IL-6 and CIMT (P<0.01). Furthermore, serum GRB2 levels (P<0.001) remained independently related to CIMT after adjusting for the age, sex, duration of diabetes, and Body Mass Index (BMI) variables. Stepwise multiple linear regression analysis showed that IL-6, HDL-C, HBA1c, and CIMT are independent correlation factors of serum GRB2 (P<0.01). Univariate logistic regression suggested that disease duration, WHR, systolic blood pressure (SBP), TG, HDL-C, HBA1c, FPG, HOMA-IR, IL-6, Hs-CRP, and GRB2 independently associated with T2DM is combined with CAS(P<0.05). And multivariate logistic regression analysis showed that duration of diabetes, IL-6, and serum GRB2 levels were independent risk factors for T2DM combined with CAS (P<0.05), and serum GRB2 levels were a highly sensitive indicator of early AS (OR=1.405, 95% CI: 1.192-1.658 P<0.001). Moreover, the ROC curve AUC area of serum GRB2 expression levels was 0.80 (95%CI: 0.7291-0.8613, P < 0.001), with a sensitivity of 83.58% and specificity of 70.59%. The risk of CAS was substantially higher in patients with T2DM whose serum GRB2 concentration was >4.59 ng/ml. Conclusions: Serum GRB2 concentrations were significantly increased in T2DM combined with CAS, and serum GRB2 levels were linearly correlated with CIMT, suggesting that GRB2 may be involved in the occurrence and development of T2DM with CAS, which can be used as a predictor of whether T2DM is combined with CAS.


Assuntos
Aterosclerose , Doenças das Artérias Carótidas , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Animais , Aterosclerose/complicações , Glicemia/análise , Proteína C-Reativa , Doenças das Artérias Carótidas/complicações , Espessura Intima-Media Carotídea , HDL-Colesterol , LDL-Colesterol , Proteína Adaptadora GRB2 , Hemoglobinas Glicadas/análise , Insulina , Resistência à Insulina/fisiologia , Interleucina-6 , NF-kappa B , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Ratos , Receptores de Fatores de Crescimento , Triglicerídeos
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