Advanced searches left 3/3

Radiation Therapy - Astrophysics Data System

Summarized by Plex Scholar
Last Updated: 12 June 2022

* If you want to update the article please login/register

An investigation of kV mini-GRID spatially fractionated radiation therapy: dosimetry and preclinical trial

"To develop and characterize novel techniques of extreme spatially fractionated kV radiation therapy in the context of a pre-clinical mouse study. " A soft tissue sarcoma cell line was introduced by intramuscular injection of a soft tissue sarcoma cell line into the gastrocnemius muscle of C57BL/6 mice. Pencil-beam GRIDs may theoretically save more intra-tumor immune cells than bar GRIDs, but they do not generally treat less tumor tissue than bar GRIDs. In tumor proliferation delay between GRID and hemi-irradiation, no significant difference was found. With kV grids, peak-to-valley ratios were two-to-five times higher than values reported in literature for MV grids, which were two-to-valley ratios. Tumor formation was delayed by GRID irradiation and hemi-irradiation, but neither was as effective as whole tumor uniform dose therapy. The combination of mini-GRID and immune checkpoint blockade is unlikely to result in an anti-cancer immune response strong enough to compare conventional RT findings, but follow-up studies will determine the combination of mini-GRID and immune checkpoint blockade. ".

Source link: https://ui.adsabs.harvard.edu/abs/2022PMB....67d5017J/abstract


Analyzing the effect of liver-tumor motion on the dosimetric error in intensity-modulated radiation therapy using the Halcyon linear accelerator

"ITV-based volumetric modulated arc therapy experiments using the Halcyon were prepared for ten cases of liver cancer, while increasing the number of arcs in the study. " To check the dosimetric accuracy of the VMAT results, quality assurance plans were developed using the Delta 4 Phantom + diode array. DQA tests were conducted in both the static and Hexa-Motion mode using the Delta 4 Hexa-Motion device to determine the movement's dosimetric precision. In the static mode, the average gamma pass rate value for the 3%/3 mm criterion and 99. 02% was 99. 98% for the 2%/2 mm criterion, which would show the proper dosimetric accuracy of the VMAT plans in this report. The dosimetric precision in the Halcyon is more affected by tumor motion in the Halcyon than by the conventional linear accelerator, despite significantly lower GPR values.

Source link: https://ui.adsabs.harvard.edu/abs/2022JKPS..tmp..125C/abstract


Modeling physician's preference in treatment plan approval of stereotactic body radiation therapy of prostate cancer

"Reatment planning of radiation therapy is a time-consuming process. " The aim of this study is to establish a deep learning-based virtual physician network that mimics physicians' choice for prostate cancer stereotactic body radiation therapy with plan approval. As an example, a plan seeking approval as input is included in the planning target number and eight organs at risk structure photographs, as well as a dose distribution of a plan seeking approval as input. In this report, 45 Gy in 5-fraction SBRT were selected, with 60 patients for preparation and cross validation, and 8 patients for independent testing. ".

Source link: https://ui.adsabs.harvard.edu/abs/2022PMB....67k5012G/abstract


Implementation of a combined theranostic x-ray irradiator/fluorescence imaging system for automatic assessment of tumor vascular response to radiation therapy

"Hypofractionated stereotactic body radiotherapy techniques have improved patient treatment outcomes. " Our method allows for the rapid assessment of spatiotemporal variations in indocyanine green kinetics in tumors using principal component analysis, both before and after tumor irradiation. Changes were discovered in the normalized first and second PC feature pixel values, according to the results. "The role of tumor perfusion in metastasis and tumor prevention will be better understood by our first-of-its-kind theranostic unit, which allows automated assessment of TVR to SBRT," says the author.

Source link: https://ui.adsabs.harvard.edu/abs/2022SPIE11944E..05N/abstract


A deep learning-based clinical target volume segmentation in female pelvic MRI for radiation therapy planning

"Brachytherapy augmented with external beam radiotherapy is the common treatment for cervical cancer. " While OAR segmentation has been widely researched, promising results, accurate tumor and/or corresponding clinical target volume segmentation have been less explored. Magnetic resonance imaging is used as the standard imaging technique to determine the CTV, which is particularly difficult because tumor cell migration is not evident even in MRI. To delineate CTV from T2-weighted MR images, we recommend a two-step convolutional neural network approach. A human expert must select a seed point inside the CTV region, from which the MR number is cut to establish a region of concern region. The proposed method was tested on the remaining 30 MR datasets and yielded Meanu00b10CD dice similarity coefficient of 0. 80 percent and Hausdorff distance of 3. 30 mm," according to the manufacturer.

Source link: https://ui.adsabs.harvard.edu/abs/2022SPIE12034E..1DZ/abstract


Automated CT segmentation for rapid assessment of anatomical variations in head-and-neck radiation therapy

"Typical radiation therapy for head-and-neck cancer patients lasts for more than a month. " Anatomical differences often occur along the course of therapy due to tumor shrinkage and weight loss, especially for head and neck cancer patients. We intend to establish a deep learning-based system for automated segmentation of multi-organs from CT head and neck images to quickly assess anatomical variations in this report. To enhance the appearance contrast around organ boundary and thus improve organ classification's ability, a hierarchical block is used. Mask head then segment organ from the VOI's updated feature map. We conducted a five-fold cross-validation of 35 patients' cases who have multiple weekly CT scans during their radiotherapy. These findings reveal the usability and effectiveness of our suggested method for multi-OAR segmentation from HN CT, which can be used to quickly determine anatomical variations in HN radiation therapy.

Source link: https://ui.adsabs.harvard.edu/abs/2022SPIE12034E..1ED/abstract


Physical characteristics of the novel transmission-target X-ray equipment for kilovoltage radiation therapy applications

"This research aims to investigate physical characteristics of a transmission-type anode X-ray unit. " This article also found the percentage depth dose and flatness and symmetry in the PTW MP3-s water tank using ionization chambers, and all of the field size measurements for the entrance surface of the water phantom was set 10 by 10 cm 2. The study also explores the effect of aluminum filter on beam quality, as well as the stability and linearity of the tube voltage and the tube current of the X-ray tube. The filter helped decrease low-energy photons by 24. 3 percent and increased the percentage of the characteristic radiation by 2. 2 percent in the energy spectrum by 2. 22%. PDD decreased dramatically making the device suitable for the clinical treatment of shallow tumors and tumor bed implantation.

Source link: https://ui.adsabs.harvard.edu/abs/2022RaPC..19710182L/abstract


Interaction of curcumin with glioblastoma cells via high and low linear energy transfer radiation therapy inducing radiosensitization effects

"Despite the high mortality rate, temozolomide has been shown to raise the survival rate of patients when combined with radiotherapy. " curcumin has also improved radiation stability under extreme and low Linear Energy Transfer radiation conditions in vitro. Cell numbers in the sub-G1 phase and the reactive oxygen species level increased in GBM cell apoptosis, which eventually led to increased GBM cellular apoptosis. In neutron -irradiated cell lines than in u03b3-irradiated cell lines, the radiosensitizing effects of curcumin are much stronger than in u03b3 -irradiated cell lines. Compared to a single treatment or curcumin combined u03b3-ray therapy,'' a cell invasion was significantly reduced during cell proliferation.

Source link: https://ui.adsabs.harvard.edu/abs/2022JRadR..63..342K/abstract


High-dimensional Automated Radiation Therapy Treatment Planning via Bayesian Optimization

"Radiation therapy administration can be viewed as an iterative hyperparameter tuning process to strike a balance between competing clinical objectives. " Twenty locally advanced rectal cancer patients treated with intensity-modulated radiation therapy were retrospectively selected as test subjects for the 20 clinical trials. One standard BO procedure and one BO solution devoted to high-dimensional problems were tested on the treatment planning task, as an automated treatment planning framework adjusts dose goals and weights simultaneously. We compared and analyzed the three automated methods' planning quality and execution effectiveness, as well as the various search styles of the two BO methods. Both experimental BO techniques were able to produce high-quality treatment plans, and the model analysis revealed the inherent low dimensionality of the tested treatment planning difficulties. ".

Source link: https://ui.adsabs.harvard.edu/abs/2022arXiv220510980W/abstract


Image-Guided Radiation Therapy; Physics and technology

"This book provides the reader with an in-depth review of physics principles and technologies of image-guided radiotherapy, which is changing the way radiotherapy is carried out. " The book covers everything from the ancient methods of using radiographic films for image guidance to the current state of the art of magnetic resonance image-guided radiotherapy, giving the reader with a historical perspective on the evolution of IGRT radiotherapy. The book is targeted at academics and students of medical physics and radiation oncology, as well as other areas that employ radiation therapy, such as neurosurgery.

Source link: https://ui.adsabs.harvard.edu/abs/2022irtp.book.....R/abstract

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions

* Please keep in mind that all text is summarized by machine, we do not bear any responsibility, and you should always check original source before taking any actions