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Abstract Background The aim of the study was to establish a weighted comprehensive evaluation model (WCEM) of image registration for cone‐beam computed tomography (CBCT) guided lung cancer radiotherapy that considers the geometric accuracy of gross target volume (GTV) and organs at risk (OARs), and assess the registration accuracy of different image registration methods to provide clinical references. Methods The planning CT and CBCT images of 20 lung cancer patients were registered using diverse algorithms (bony and grayscale) and regions of interest (target, ipsilateral, and body). We compared the coverage ratio (CR) of the planning target volume (PTVCT) to GTVCBCT, as well as the dice similarity coefficient (DSC) of the GTV and OARs, considering the treatment position across various registration methods. Furthermore, we developed a mathematical model to assess registration results comprehensively. This model was evaluated and validated using CRFs across four automatic registration methods. Results The grayscale registration method, coupled with the registration of the ipsilateral structure, exhibited the highest level of automatic registration accuracy, the DSC were 0.87 ± 0.09 (GTV), 0.71 ± 0.09 (esophagus), 0.74 ± 0.09 (spinal cord), and 0.91 ± 0.05 (heart), respectively. Our proposed WCEM proved to be both practical and effective. The results clearly indicated that the grayscale registration method, when applied to the ipsilateral structure, achieved the highest CRF score. The average CRF scores, excellent rates, good rate and qualification rates were 58 ± 26, 40%, 75%, and 85%, respectively. Conclusions This study successfully developed a clinically relevant weighted evaluation model for CBCT‐guided lung cancer radiotherapy. Validation confirmed the grayscale method's optimal performance in ipsilateral structure registration.

To investigate the effect of different MR sequences on the accuracy of Cycle-consistent Generative Adversarial Network (CycleGAN) based synthetic CT (sCT) generation in nasopharyngeal carcinoma (NPC). In this work, three sequences of MR, included T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), and T1 contrast-enhanced weighted imaging (T1WIC), and planning CT (PCT) images of 151 patients with NPC were collected. The number of training, verification, and test sets were 108, 16, and 27, respectively. Three unsupervised CycleGAN-based models were trained using different sequences (single channels) as inputs, and the synergistic fusion model were used multiple channels. To assess the precision of these models, we evaluated key metrics such as mean error (ME), mean absolute error (MAE), structural similarity index (SSIM), peak signal-to-noise ratio (PSNR), and dose distribution, comparing the PCT with the sCT generated by each model. Overall, The SCTT2 image generated by T2WI model achieved superior results than those of T1WIC and T1WI for a single-sequence model. Compared to the SCTT2, the quality of the SCTFusion image generated by the fusion model was further improved, with significant differences in the MAE, SSIM, and PNSR metrics (P $112.97\pm 9.69$ vs. $90.99\pm 9.64$ , P $0.86\pm 0.02$ vs. $0.89\pm 0.02$ , P $21.66\pm 0.64$ vs. $23.28\pm 0.87$ , P $\pm ~1.05$ % and 0.73%±0.73% for the fusion model. In conclusion, our findings reveal that the CycleGAN model, particularly when employing fusion MR sequences as input, offers the highest accuracy in synthetic CT generation. Notably, T2WI images stand out as a viable option for sCT prediction in clinical settings where acquisition sequences or times are limited.

Purpose: Intensity-modulated radiotherapy (IMRT) is currently the most important treatment method for nasopharyngeal carcinoma (NPC). This study aimed to enhance prediction accuracy by incorporating dose information into a deep convolutional neural network (CNN) using a multichannel input method. Methods: A target conformal plan (TCP) was created based on the maximum planning target volume (PTV). Input data included TCP dose distribution, images, target structures, and organ-at-risk (OAR) information. The role of target conformal plan dose (TCPD) was assessed by comparing the TCPD–CNN (with dose information) and NonTCPD–CNN models (without dose information) using statistical analyses with the ranked Wilcoxon test ( P

IntroductionCerebral small vessel disease (SVD) affects older adults, but traditional approaches have limited the understanding of the neural mechanisms of SVD. This study aimed to explore the effects of SVD on brain regions and its association with cognitive decline using the four-dimensional (spatiotemporal) consistency of local neural activity (FOCA) method.MethodsMagnetic resonance imaging data from 42 patients with SVD and 38 healthy controls (HCs) were analyzed using the FOCA values. A two-sample t test was performed to compare the differences in FOCA values in the brain between the HCs and SVD groups. Pearson correlation analysis was conducted to analyze the association of various brain regions with SVD scores.ResultsThe results revealed that the FOCA values in the right frontal_inf_oper, right temporal_pole_sup, and default mode network decreased, whereas those in the temporal_inf, hippocampus, basal ganglia, and cerebellum increased, in patients with SVD. Most of these varying brain regions were negatively correlated with SVD scores.DiscussionThis study suggested that the FOCA approach might have the potential to provide useful insights into the understanding of the neurophysiologic mechanisms of patients with SVD.

Abstract This study aims to determine whether the dual-parameter approach combined with either time-resolved angiography with stochastic trajectories (TWIST) or golden-angle radial sparse parallel (GRASP) and diffusion-weighted imaging (DWI) has superior diagnostic performance in predicting pathological lymphovascular invasion (pLVI) rectal cancer when compared with traditional single-parameter evaluations using DWI alone. Patients with pathologically confirmed rectal cancer were enrolled. Perfusion (influx forward volume transfer constant [Ktrans] and rate constant [Kep]) and apparent diffusion coefficient (ADC) were measured by two researchers. For both sequences, areas under receiver operating characteristic (ROCs) to predict pLVI-positive rectal cancer were compared. A total of 179 patients were enrolled in our study. A combined analysis of ADC and perfusion parameters (Ktrans) acquired with GRASP yielded a higher diagnostic performance compared with diffusion parameters alone (area under the curve, 0.91 ± 0.03 vs. 0.71 ± 0.06, P

The maturation of human stem cell-derived cardiomyocytes (hSC-CMs) has been a major challenge to further expand the scope of their application. Over the past years, several strategies have been proven to facilitate the structural and functional maturation of hSC-CMs, which include but are not limited to engineering the geometry or stiffness of substrates, providing favorable extracellular matrices, applying mechanical stretch, fluidic or electrical stimulation, co-culturing with niche cells, regulating biochemical cues such as hormones and transcription factors, engineering and redirecting metabolic patterns, developing 3D cardiac constructs such as cardiac organoid or engineered heart tissue, or culturing under in vivo implantation. In this review, we summarize these maturation strategies, especially the recent advancements, and discussed their advantages as well as the pressing problems that need to be addressed in future studies.

Background and Purpose: In this study, the absolute dose achievable between helical tomotherapy (HT) plans and RapidArc (RA) plans for total dura mater irradiation (TDMI) was compared. Materials and methods: A planning study was conducted on nine children's case datasets with dura mater metastasis of neuroblastoma. The target included the entire calvarium and skull base and formed a closed volume with a certain thickness around the brain. HT and RA plans with four coplanar full arcs (RA4) with half-field technique were generated for the comparison of absolute dose achievable. In total, 30.6 Gy was prescribed as D 95% (ie, dose to 95% of PTV volume). Results: In the dosimetric comparison between the two modalities, HT provided more homogenous dose distribution than RA4 (mean HI 5−95% : 1.046 vs 1.088, P

Purpose: To aid in the selection of a suitable combination of irradiation mode and jaw width in helical tomotherapy (HT) for the treatment of nasopharyngeal carcinoma (NPC).Materials and Methods: Twenty patients with NPC who underwent radiotherapy were retrospectively selected. Four plans using a jaw width of 2.5 or 5-cm in dynamic jaw (DJ) or fix jaw (FJ) modes for irradiation were designed (2.5DJ, 2.5FJ, 5.0DJ, and 5.0FJ). The dose parameters of planning target volume (PTV) and organs at risk (OARs) of the plans were compared and analyzed, as well as the beam on time (BOT) and monitor unit (MU). The plans in each group were ranked by scoring the doses received by the OARs and the superity was assessed in combination with the planned BOT and MU.Results: The prescribed dose coverage of PTV met the clinical requirements for all plans in the four groups. The groups using a 2.5-cm jaw width or a DJ mode provided better protection to most OARs, particularly for those at the longitudinal edges of the PTV (P < 0.05). The 2.5DJ group had the best ranking for OAR-dose, followed by the 2.5FJ and 5.0DJ groups with a same score. The BOT and MU of the groups using a 5.0-cm jaw width reduced nearly 45% comparing to those of the 2.5-cm jaw groups.Conclusion: 2.5DJ has the best dose distribution, while 5.0DJ has satisfactory dose distribution and less BOT and MU that related to the leakage dose. Both 2.5DJ or 5DJ were recommended for HT treatment plan for NPC based on the center workload.