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Development and characterization of the first proton minibeam system for single‐gantry proton facility Med Phys (IF 3.8) Pub Date : 2024-04-20 Yuting Lin, Wangyao Li, Daniel Johnson, Yolanda Prezado, Gregory N. Gan, Hao Gao
BackgroundMinibeam represents a preclinical spatially fractionated radiotherapy modality with great translational potential. The advantage lies in its high therapeutic index (compared to GRID and LATTICE) and ability to treat at greater depth (compared to microbeam). Proton minibeam radiotherapy (pMBRT) is a synergy of proton and minibeam. While the single‐gantry proton facility has gained popularity
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MRI‐based clinical‐radiomics nomogram model for predicting microvascular invasion in hepatocellular carcinoma Med Phys (IF 3.8) Pub Date : 2024-04-20 Qinghua Wang, Yongjie Zhou, Hongan Yang, Jingrun Zhang, Xianjun Zeng, Yongming Tan
BackgroundPreoperative microvascular invasion (MVI) of liver cancer is an effective method to reduce the recurrence rate of liver cancer. Hepatectomy with extended resection and additional adjuvant or targeted therapy can significantly improve the survival rate of MVI+ patients by eradicating micrometastasis. Preoperative prediction of MVI status is of great clinical significance for surgical decision‐making
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Evaluating the relationship between magnetic resonance image quality metrics and deep learning‐based segmentation accuracy of brain tumors Med Phys (IF 3.8) Pub Date : 2024-04-19 Rajarajeswari Muthusivarajan, Adrian Celaya, Joshua P. Yung, James P. Long, Satish E. Viswanath, Daniel S. Marcus, Caroline Chung, David Fuentes
BackgroundMagnetic resonance imaging (MRI) scans are known to suffer from a variety of acquisition artifacts as well as equipment‐based variations that impact image appearance and segmentation performance. It is still unclear whether a direct relationship exists between magnetic resonance (MR) image quality metrics (IQMs) (e.g., signal‐to‐noise, contrast‐to‐noise) and segmentation accuracy.PurposeDeep
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Automated determination of the ion‐recombination correction factor (ksat) in ultra‐high dose rate electron radiation therapy Med Phys (IF 3.8) Pub Date : 2024-04-19 Michaël Claessens, Verdi Vanreusel, Alessia Gasparini, Luana de Freitas Nascimento, Burak Yalvec, Brigitte Reniers, Dirk Verellen
BackgroundPlane‐parallel ionization chambers are the recommended secondary standard systems for clinical reference dosimetry of electrons. Dosimetry in high dose rate and dose‐per‐pulse (DPP) is challenging as ionization chambers are subject to ion recombination, especially when dose rate and/or DPP is increased beyond the range of conventional radiotherapy. The lack of universally accepted models
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Deep learning‐based optimization of field geometry for total marrow irradiation delivered with volumetric modulated arc therapy Med Phys (IF 3.8) Pub Date : 2024-04-18 Nicola Lambri, Giorgio Longari, Daniele Loiacono, Ricardo Coimbra Brioso, Leonardo Crespi, Carmela Galdieri, Francesca Lobefalo, Giacomo Reggiori, Roberto Rusconi, Stefano Tomatis, Luisa Bellu, Stefania Bramanti, Elena Clerici, Chiara De Philippis, Damiano Dei, Pierina Navarria, Carmelo Carlo‐Stella, Ciro Franzese, Marta Scorsetti, Pietro Mancosu
BackgroundTotal marrow (lymphoid) irradiation (TMI/TMLI) is a radiotherapy treatment used to selectively target the bone marrow and lymph nodes in conditioning regimens for allogeneic hematopoietic stem cell transplantation. A complex field geometry is needed to cover the large planning target volume (PTV) of TMI/TMLI with volumetric modulated arc therapy (VMAT). Five isocenters and ten overlapping
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Color VISION for improved ultrasound visualization of brachytherapy needles Med Phys (IF 3.8) Pub Date : 2024-04-17 Justine M. Dupere, Eric E. Brost, Matthew E. Hainy, Christine U. Lee, Matthew W. Urban, Bradley J. Stish, Christopher L. Deufel
BackgroundHigh dose rate brachytherapy is commonly used in the treatment of prostate cancer. Treatment planning is often performed under transrectal ultrasound (US) guidance, but brachytherapy needles can be challenging to digitize due to the presence of poor US conspicuity and imaging artifacts. The plan accuracy and quality, however, are dependent on the proper visualization of the needles with millimeter
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Dosimetric study for breathing‐induced motion effects in an abdominal pancreas phantom for carbon ion mini‐beam radiotherapy Med Phys (IF 3.8) Pub Date : 2024-04-17 Christina Stengl, Iván D. Muñoz, Eric Arbes, Evelyn Rauth, Jeppe B. Christensen, José Vedelago, Armin Runz, Oliver Jäkel, Joao Seco
BackgroundParticle mini‐beam therapy exhibits promise in sparing healthy tissue through spatial fractionation, particularly notable for heavy ions, further enhancing the already favorable differential biological effectiveness at both target and entrance regions. However, breathing‐induced organ motion affects particle mini‐beam irradiation schemes since the organ displacements exceed the mini‐beam
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Incorporating plan complexity into the statistical process control of volumetric modulated arc therapy pre‐treatment verifications Med Phys (IF 3.8) Pub Date : 2024-04-17 Serenella Russo, Jordi Saez, Marco Esposito, Andrea Bruschi, Alessandro Ghirelli, Silvia Pini, Silvia Scoccianti, Victor Hernandez
BackgroundStatistical process control (SPC) is a powerful statistical tool for process monitoring that has been highly recommended in healthcare applications, including radiation therapy quality assurance (QA). The AAPM TG‐218 report described the clinical implementation of SPC for Volumetric Modulated Arc Therapy (VMAT) pre‐treatment verifications, pointing out the need to adjust tolerance limits
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High‐resolution 3T to 7T ADC map synthesis with a hybrid CNN‐transformer model Med Phys (IF 3.8) Pub Date : 2024-04-17 Zach Eidex, Jing Wang, Mojtaba Safari, Eric Elder, Jacob Wynne, Tonghe Wang, Hui‐Kuo Shu, Hui Mao, Xiaofeng Yang
Background7 Tesla (7T) apparent diffusion coefficient (ADC) maps derived from diffusion‐weighted imaging (DWI) demonstrate improved image quality and spatial resolution over 3 Tesla (3T) ADC maps. However, 7T magnetic resonance imaging (MRI) currently suffers from limited clinical unavailability, higher cost, and increased susceptibility to artifacts.PurposeTo address these issues, we propose a hybrid
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Fully automated explainable abdominal CT contrast media phase classification using organ segmentation and machine learning Med Phys (IF 3.8) Pub Date : 2024-04-17 Yazdan Salimi, Zahra Mansouri, Ghasem Hajianfar, Amirhossein Sanaat, Isaac Shiri, Habib Zaidi
BackgroundContrast‐enhanced computed tomography (CECT) provides much more information compared to non‐enhanced CT images, especially for the differentiation of malignancies, such as liver carcinomas. Contrast media injection phase information is usually missing on public datasets and not standardized in the clinic even in the same region and language. This is a barrier to effective use of available
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AAPM WGVRTO report 390: A survey of veterinary radiation oncology equipment and infrastructure in 2022 Med Phys (IF 3.8) Pub Date : 2024-04-16 Parminder S. Basran, Michelle Turek, Kimberly A. Selting, Nicholas Rancilio
Since 2010, there has been little published data on the state of equipment and infrastructure in veterinary radiation oncology clinical practice. These data are important not only to identify the status and use of technology within the veterinary radiation oncology community but also to help identify the extent of medical physics support. The purpose of our study is to report findings from a survey
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Aberration correction by polynomial approximation for synthetic aperture ultrasound imaging Med Phys (IF 3.8) Pub Date : 2024-04-14 Denis Leonov, Nicholas Kulberg, Tatyana Yakovleva
BackgroundPreviously, there has been some work in the field of optical imaging on phase compensation by employing Legendre polynomials as an expansion of the phase function, and this seems to be an appealing unstudied area in the field of ultrasound imaging.PurposeThe paper is devoted to solving one of the problems of enhancing the authenticity of diagnostics data obtained in ultrasound visualization
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Learning with privileged knowledge of multiple kernels via joint prediction for CT Kernel conversion Med Phys (IF 3.8) Pub Date : 2024-04-12 Chudi Hu, Gang Chen
BackgroundMost existing models for CT kernel conversion take images reconstructed with a single predetermined source kernel as input and convert them to images that are reconstructed with a target kernel. However, these models can achieve even better performance if they leverage complementary information obtained from images reconstructed with multiple different kernels. In many clinical practice scenarios
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Technical note: Visual, rapid, scintillation point dosimetry for in vivo MV photon beam radiotherapy treatments Med Phys (IF 3.8) Pub Date : 2024-04-10 Savannah M. Decker, Petr Bruza, Rongxiao Zhang, Benjamin B. Williams, Lesley A. Jarvis, Brian W. Pogue, David J. Gladstone
BackgroundWhile careful planning and pre‐treatment checks are performed to ensure patient safety during external beam radiation therapy (EBRT), inevitable daily variations mean that in vivo dosimetry (IVD) is the only way to attain the true delivered dose. Several countries outside the US require daily IVD for quality assurance. However, elsewhere, the manual labor and time considerations of traditional
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Ultrasonic surface acoustic wave elastography: A review of basic theories, technical developments, and medical applications Med Phys (IF 3.8) Pub Date : 2024-04-10 Abdullah Al Masud, Jingfei Liu
Physiological and pathological changes in tissues often cause changes in tissue mechanical properties, making tissue elastography an effective modality in medical imaging. Among the existing elastography methods, ultrasound elastography is of great interest due to the inherent advantages of ultrasound imaging technology, such as low cost, portability, safety, and wide availability. However, most current
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Technical note: Characterization, validation, and spectral optimization of a dedicated breast CT system for contrast‐enhanced imaging Med Phys (IF 3.8) Pub Date : 2024-04-10 Juan J. Pautasso, Koen Michielsen, Ioannis Sechopoulos
BackgroundThe development of a new imaging modality, such as 4D dynamic contrast‐enhanced dedicated breast CT (4D DCE‐bCT), requires optimization of the acquisition technique, particularly within the 2D contrast‐enhanced imaging modality. Given the extensive parameter space, cascade‐systems analysis is commonly used for such optimization.PurposeTo implement and validate a parallel‐cascaded model for
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A noise robust image reconstruction using slice aware cycle interpolator network for parallel imaging in MRI Med Phys (IF 3.8) Pub Date : 2024-04-10 Jeewon Kim, Wonil Lee, Beomgu Kang, Hyunseok Seo, HyunWook Park
BackgroundReducing Magnetic resonance imaging (MRI) scan time has been an important issue for clinical applications. In order to reduce MRI scan time, imaging acceleration was made possible by undersampling k‐space data. This is achieved by leveraging additional spatial information from multiple, independent receiver coils, thereby reducing the number of sampled k‐space lines.PurposeThe aim of this
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Technical note: Radiological clinical equivalence for phantom materials in carbon ion therapy Med Phys (IF 3.8) Pub Date : 2024-04-10 Paige A. Taylor, Alfredo Mirandola, Mario Ciocca, Shannon Hartzell, Alessandro Vai, Paola Alvarez, Rebecca M. Howell, Eugene J. Koay, Christopher R. Peeler, Christine B. Peterson, Stephen F. Kry
PurposeAs carbon ion radiotherapy increases in use, there are limited phantom materials for heterogeneous or anthropomorphic phantom measurements. This work characterized the radiological clinical equivalence of several phantom materials in a therapeutic carbon ion beam.MethodsEight materials were tested for radiological material‐equivalence in a carbon ion beam. The materials were computed tomography
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Knowledge‐based planning for Gamma Knife Med Phys (IF 3.8) Pub Date : 2024-04-10 Binghao Zhang, Aaron Babier, Mark Ruschin, Timothy C. Y. Chan
BackgroundCurrent methods for Gamma Knife (GK) treatment planning utilizes either manual forward planning, where planners manually place shots in a tumor to achieve a desired dose distribution, or inverse planning, whereby the dose delivered to a tumor is optimized for multiple objectives based on established metrics. For other treatment modalities like IMRT and VMAT, there has been a recent push to
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Secondary neutron dosimetry for conformal FLASH proton therapy Med Phys (IF 3.8) Pub Date : 2024-04-10 Dixin Chen, Seyyedeh Azar Oliaei Motlagh, François Vander Stappen, Rudi Labarbe, Beryl Bell, Michele Kim, Boon‐Keng Kevin Teo, Lei Dong, Wei Zou, Eric Stanton Diffenderfer
BackgroundCyclotron‐based proton therapy systems utilize the highest proton energies to achieve an ultra‐high dose rate (UHDR) for FLASH radiotherapy. The deep‐penetrating range associated with this high energy can be modulated by inserting a uniform plate of proton‐stopping material, known as a range shifter, in the beam path at the nozzle to bring the Bragg peak within the target while ensuring high
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Fully automatic online geometric calibration for non-circular cone-beam CT orbits using fiducials with unknown placement Med Phys (IF 3.8) Pub Date : 2024-04-04 Yiqun Q. Ma, Tess Reynolds, Tina Ehtiati, Clifford Weiss, Kelvin Hong, Nicholas Theodore, Grace J. Gang, J. Webster Stayman
Cone-beam CT (CBCT) with non-circular scanning orbits can improve image quality for 3D intraoperative image guidance. However, geometric calibration of such scans can be challenging. Existing methods typically require a prior image, specialized phantoms, presumed repeatable orbits, or long computation time.
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Simulated error training for the physics plan and chart review Med Phys (IF 3.8) Pub Date : 2024-04-08 Perry B. Johnson, Leah Schubert, Grace Gwe‐Ya Kim, Jacqueline Faught, Courtney Buckey, Leigh Conroy, Samuel M. H. Luk, Deborah Schofield, Stephanie Parker
BackgroundSimulated error training is a method to practice error detection in situations where the occurrence of error is low. Such is the case for the physics plan and chart review where a physicist may check several plans before encountering a significant problem. By simulating potentially hazardous errors, physicists can become familiar with how they manifest and learn from mistakes made during
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3D printed phantom with 12 000 submillimeter lesions to improve efficiency in CT detectability assessment Med Phys (IF 3.8) Pub Date : 2024-04-08 Picha Shunhavanich, Kai Mei, Nadav Shapira, Joseph Webster Stayman, Cynthia H. McCollough, Grace Gang, Shuai Leng, Michael Geagan, Lifeng Yu, Peter B. Noël, Scott S. Hsieh
BackgroundThe detectability performance of a CT scanner is difficult to precisely quantify when nonlinearities are present in reconstruction. An efficient detectability assessment method that is sensitive to small effects of dose and scanner settings is desirable. We previously proposed a method using a search challenge instrument: a phantom is embedded with hundreds of lesions at random locations
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Full‐dose whole‐body PET synthesis from low‐dose PET using high‐efficiency denoising diffusion probabilistic model: PET consistency model Med Phys (IF 3.8) Pub Date : 2024-04-08 Shaoyan Pan, Elham Abouei, Junbo Peng, Joshua Qian, Jacob F Wynne, Tonghe Wang, Chih‐Wei Chang, Justin Roper, Jonathon A Nye, Hui Mao, Xiaofeng Yang
PurposePositron Emission Tomography (PET) has been a commonly used imaging modality in broad clinical applications. One of the most important tradeoffs in PET imaging is between image quality and radiation dose: high image quality comes with high radiation exposure. Improving image quality is desirable for all clinical applications while minimizing radiation exposure is needed to reduce risk to patients
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Estimation of the relative biological effectiveness for double strand break induction of clinical kilovoltage beams using Monte Carlo simulations Med Phys (IF 3.8) Pub Date : 2024-04-08 Oran McElligott, Mihails Nikandrovs, Patrick McCavana, Brendan McClean, Luis León Vintró
BackgroundThe Relative Biological Effectiveness (RBE) of kilovoltage photon beams has been previously investigated in vitro and in silico using analytical methods. The estimated values range from 1.03 to 1.82 depending on the methodology and beam energies examined.PurposeThe focus of this work was to independently estimate RBE values for a range of clinically used kilovoltage beams (70–200 kVp) while
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Validation of daily 0.35 T diffusion‐weighted MRI for MRI‐guided glioblastoma radiotherapy Med Phys (IF 3.8) Pub Date : 2024-04-08 Natalia Lutsik, Siamak P. Nejad‐Davarani, Alessandro Valderrama, Janette Herr, Danilo Maziero, Kaylie Cullison, Gregory A. Azzam, Gregory J Kubicek, Jessica Meshman, Macarena I. de la Fuente, Tess Armstrong, Eric A. Mellon
BackgroundMRI‐Linac systems enable daily diffusion‐weighed imaging (DWI) MRI scans for assessing glioblastoma tumor changes with radiotherapy treatment.PurposeOur study assessed the image quality of echoplanar imaging (EPI)‐DWI scans compared with turbo spin echo (TSE)‐DWI scans at 0.35 Tesla (T) and compared the apparent diffusion coefficient (ADC) values and distortion of EPI‐DWI on 0.35 T MRI‐Linac
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Dose rate conversion coefficients for ocular contamination in nuclear medicine: A Monte Carlo simulation with experimental validation Med Phys (IF 3.8) Pub Date : 2024-04-08 Eva J. I. Hoeijmakers, Kes Hoenen, Matthias Bauwens, Daniëlle B. P. Eekers, Cécile R. L. P. N. Jeukens, Roel Wierts
BackgroundSince 2011, the International Commission on Radiological Protection (ICRP) has recommended an annual eye lens dose limit of 20 mSv for radiation workers, averaged over 5 years, with no year exceeding 50 mSv. However, limited research has been conducted on dose rate conversion coefficients (DCCs) for direct contamination of the eye.PurposeThis study aimed to accurately determine DCCs for the
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Detection of early pulmonary emphysema by multi‐contrast x‐ray Talbot‐Lau interferometer Med Phys (IF 3.8) Pub Date : 2024-04-05 Qisi Lin, Zhao Wu, Meng Huang, Zheng Dang, Lijiao Tian, Yong Guan, Gang Liu, Yalin Lu, Yangchao Tian
BackgroundPulmonary emphysema is a part of chronic obstructive pulmonary disease, which is an irreversible chronic respiratory disease. In order to avoid further damage to lung tissue, early diagnosis and treatment of pulmonary emphysema is essential.PurposeEarly pulmonary emphysema diagnosis is difficult with conventional radiographic imaging. Recently, x‐ray phase contrast imaging has proved to be
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In reply to Masjedi et al Med Phys (IF 3.8) Pub Date : 2024-04-04 Marco Carlone, Ray Yang, Derek Hyde, Nathan Becker, John Cocarell
We thank Dr. Masjedi for taking the time to review our paper, Measurement of neutron yield for a medical linear accelerator below 10 MV,1 and to provide thoughtful commentary on our experimental methods. The motivation for this work was to address the lack of experimental data in the literature regarding neutron doses from medical linear accelerators at intermediate energies, between 6 and 10 MV. Medical
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In response to “Measurement of neutron yield for a medical linear accelerator below 10 MV” Med Phys (IF 3.8) Pub Date : 2024-04-04 Hamidreza Masjedi
Medical Physics recently published an article by Carlone et al. entitled “Measurement of neutron yield for a medical linear accelerator below 10 MV”.1 The authors conducted measurements to evaluate the level of photoneutron contamination from a Varian linear accelerator at intermediate photon energies (6–15 MV) by adjusting the bending magnet (Bmag) current. While the methodology of the survey is unique
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Estimate and compensate head motion in non-contrast head CT scans using partial angle reconstruction and deep learning Med Phys (IF 3.8) Pub Date : 2024-04-03 Zhennong Chen, Quanzheng Li, Dufan Wu
Patient head motion is a common source of image artifacts in computed tomography (CT) of the head, leading to degraded image quality and potentially incorrect diagnoses. The partial angle reconstruction (PAR) means dividing the CT projection into several consecutive angular segments and reconstructing each segment individually. Although motion estimation and compensation using PAR has been developed
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Two-dimensional time-resolved scintillating sheet monitoring of proton pencil beam scanning FLASH mouse irradiations Med Phys (IF 3.8) Pub Date : 2024-04-03 Eleni Kanouta, Petr Bruza, Jacob Graversen Johansen, Line Kristensen, Brita Singers Sørensen, Per Rugaard Poulsen
Dosimetry in pre-clinical FLASH studies is essential for understanding the beam delivery conditions that trigger the FLASH effect. Resolving the spatial and temporal characteristics of proton pencil beam scanning (PBS) irradiations with ultra-high dose rates (UHDR) requires a detector with high spatial and temporal resolution.
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Enhancing adaptive proton therapy through CBCT images: Synthetic head and neck CT generation based on 3D vision transformers Med Phys (IF 3.8) Pub Date : 2024-04-03 David Viar-Hernandez, Juan Manuel Molina-Maza, Juan Antonio Vera-Sánchez, Juan Maria Perez-Moreno, Alejandro Mazal, Borja Rodriguez-Vila, Norberto Malpica, Angel Torrado-Carvajal
Proton therapy is a form of radiotherapy commonly used to treat various cancers. Due to its high conformality, minor variations in patient anatomy can lead to significant alterations in dose distribution, making adaptation crucial. While cone-beam computed tomography (CBCT) is a well-established technique for adaptive radiation therapy (ART), it cannot be directly used for adaptive proton therapy (APT)
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A medical image segmentation method for rectal tumors based on multi‐scale feature retention and multiple attention mechanisms Med Phys (IF 3.8) Pub Date : 2024-04-03 Jumin Zhao, Linjun Liu, Xiaotang Yang, Yanfen Cui, Dengao Li, Huiting Zhang, Kenan Zhang
BackgroundWith the continuous development of deep learning algorithms in the field of medical images, models for medical image processing based on convolutional neural networks have made great progress. Since medical images of rectal tumors are characterized by specific morphological features and complex edges that differ from natural images, achieving good segmentation results often requires a higher
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NaI gamma camera performance for high energies: Effects of crystal thickness, photomultiplier tube geometry and light guide thickness Med Phys (IF 3.8) Pub Date : 2024-04-03 Valerio Cosmi, Beien Wang, Marlies C. Goorden, Freek J. Beekman
BackgroundGamma camera imaging, including single photon emission computed tomography (SPECT), is crucial for research, diagnostics, and radionuclide therapy. Gamma cameras are predominantly based on arrays of photon multipliers tubes (PMTs) that read out NaI(Tl) scintillation crystals. In this way, standard gamma cameras can localize ɣ‐rays with energies typically ranging from 30 to 360 keV. In the
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Robustness of carbon‐ion radiotherapy against DNA damage repair associated radiosensitivity variation based on a biophysical model Med Phys (IF 3.8) Pub Date : 2024-04-03 Hans Liew, Thomas Tessonnier, Stewart Mein, Giuseppe Magro, Lars Glimelius, Elias Coniavitis, Thomas Held, Thomas Haberer, Amir Abdollahi, Jürgen Debus, Ivana Dokic, Andrea Mairani
BackgroundInterpatient variation of tumor radiosensitivity is rarely considered during the treatment planning process despite its known significance for the therapeutic outcome.PurposeTo apply our mechanistic biophysical model to investigate the biological robustness of carbon ion radiotherapy (CIRT) against DNA damage repair interference (DDRi) associated patient‐to‐patient variability in radiosensitivity
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A re‐activation model for 169Yb intensity modulated brachytherapy sources accounting for spatiotemporal isotopic composition Med Phys (IF 3.8) Pub Date : 2024-04-01 Ryan T. Flynn, Blake R. Smith, Quentin E. Adams, Kaustubh Patwardhan, Stephen A. Graves, Karolyn M. Hopfensperger
BackgroundIntensity modulated brachytherapy based on partially shielded intracavitary and interstitial applicators is possible with a cost‐effective 169Yb production method. 169Yb is a traditionally expensive isotope suitable for this purpose, with an average γ‐ray energy of 93 keV. Re‐activating a single 169Yb source multiple times in a nuclear reactor between clinical uses was shown to theoretically
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Identifying gray matter alterations in Cushing's disease using machine learning: An interpretable approach Med Phys (IF 3.8) Pub Date : 2024-04-01 Yue Long, Jie Ren, FuChao Cheng, YuMei Duan, BaoFeng Wang, Yuhao Sun, QingFang Sun, LiuGuan Bian, JunChen Yi, Ying Qin, RongBing Huang, WeiTong Guo, Hong Jiang, Chang Liu, Xiao Feng, Ling Qin
BackgroundCushing's Disease (CD) is a rare clinical syndrome characterized by excessive secretion of adrenocorticotrophic hormone, leading to significant functional and structural brain alterations as observed in Magnetic Resonance Imaging (MRI). While traditional statistical analysis has been widely employed to investigate these MRI changes in CD, it has lacked the ability to predict individual‐level
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A four‐grating interferometer for x‐ray multi‐contrast imaging Med Phys (IF 3.8) Pub Date : 2024-04-01 Houxun Miao, James C. Williams, Daniel Josell
BackgroundX‐ray multi‐contrast imaging with gratings provides a practical method to detect differential phase and dark‐field contrast images in addition to the x‐ray absorption image traditionally obtained in laboratory or hospital environments. Systems have been developed for preclinical applications in areas including breast imaging, lung imaging, rheumatoid arthritis hand imaging and kidney stone
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Image quality evaluation in deep‐learning‐based CT noise reduction using virtual imaging trial methods: Contrast‐dependent spatial resolution Med Phys (IF 3.8) Pub Date : 2024-03-31 Zhongxing Zhou, Hao Gong, Scott Hsieh, Cynthia H. McCollough, Lifeng Yu
BackgroundDeep‐learning‐based image reconstruction and noise reduction methods (DLIR) have been increasingly deployed in clinical CT. Accurate image quality assessment of these methods is challenging as the performance measured using physical phantoms may not represent the true performance of DLIR in patients since DLIR is trained mostly on patient images.PurposeIn this work, we aim to develop a patient‐data‐based
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Adaptable cascaded registration for personalized maxilla completion and cleft defect volume estimation Med Phys (IF 3.8) Pub Date : 2024-03-31 Yungeng Zhang, Yuru Pei, Yixiao Guo, Si Chen, Zhi‐bo Zhou, Tianmin Xu, Hongbin Zha
BackgroundCone‐beam computed tomography (CBCT) images provide high‐resolution insights into the underlying craniofacial anomaly in patients with cleft lip and palate (CLP), requiring non‐negligible annotation costs to measure the cleft defect for the guidance of the clinical secondary alveolar bone graft procedures. Considering the cumbersome volumetric image acquisition, there is a lack of paired
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Benchmarking machine learning‐based real‐time respiratory signal predictors in 4D SBRT Med Phys (IF 3.8) Pub Date : 2024-03-27 Lukas Wimmert, Maximilian Nielsen, Frederic Madesta, Tobias Gauer, Christian Hofmann, Rene Werner
BackgroundStereotactic body radiotherapy of thoracic and abdominal tumors has to account for respiratory intrafractional tumor motion. Commonly, an external breathing signal is continuously acquired that serves as a surrogate of the tumor motion and forms the basis of strategies like breathing‐guided imaging and gated dose delivery. However, due to inherent system latencies, there exists a temporal
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Lung CT harmonization of paired reconstruction kernel images using generative adversarial networks Med Phys (IF 3.8) Pub Date : 2024-03-26 Aravind R. Krishnan, Kaiwen Xu, Thomas Z. Li, Lucas W. Remedios, Kim L. Sandler, Fabien Maldonado, Bennett A. Landman
BackgroundThe kernel used in CT image reconstruction is an important factor that determines the texture of the CT image. Consistency of reconstruction kernel choice is important for quantitative CT‐based assessment as kernel differences can lead to substantial shifts in measurements unrelated to underlying anatomical structures.PurposeIn this study, we investigate kernel harmonization in a multi‐vendor
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PET/SPECT/Spectral‐CT/CBCT imaging in a small‐animal radiation therapy platform: A Monte Carlo study—Part II: Biologically guided radiotherapy Med Phys (IF 3.8) Pub Date : 2024-03-22 Xiadong Li, Hui Wang, Lixia Xu, Yu Kuang
BackgroundThis study addresses the technical gap between clinical radiation therapy (RT) and preclinical small‐animal RT, hindering the comprehensive validation of innovative clinical RT approaches in small‐animal models of cancer and the translation of preclinical RT studies into clinical practices.PurposeThe main aim was to explore the feasibility of biologically guided RT implemented within a small‐animal
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Physical dose validation of dynamic treatment for Gamma Knife radiosurgery Med Phys (IF 3.8) Pub Date : 2024-03-22 Benjamin Z. Tham, Dionne M. Aleman, Robert K. Heaton, Håkan Nordström, Catherine Coolens
BackgroundDynamic treatment in Gamma Knife (GK) radiosurgery systems delivers radiation continuously with couch movement, as opposed to stationary step‐and‐shoot treatment where radiation is paused when moving between isocenters. Previous studies have shown the potential for dynamic GK treatment to give faster treatment times and improved dose conformity and homogeneity. However, these studies focused
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Superparamagnetic iron oxide nanoparticle enhanced percutaneous microwave ablation: Ex‐vivo characterization using magnetic resonance thermometry Med Phys (IF 3.8) Pub Date : 2024-03-21 Sharath K. Bhagavatula, Sajanlal R. Panikkanvalappil, Junichi Tokuda, Vincent Levesque, Zuzana Tatarova, Guigen Liu, John E. Markert, Oliver Jonas
BackgroundPercutaneous microwave ablation (pMWA) is a minimally invasive procedure that uses a microwave antenna placed at the tip of a needle to induce lethal tissue heating. It can treat cancer and other diseases with lower morbidity than conventional surgery, but one major limitation is the lack of control over the heating region around the ablation needle. Superparamagnetic iron oxide nanoparticles
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CT‐based radiomics for differentiating peripherally located pulmonary sclerosing pneumocytoma from carcinoid Med Phys (IF 3.8) Pub Date : 2024-03-20 Yi Zhang, Xiaohuang Yang, Feng Bi, Lu Wen, Yue Niu, Yanhui Yang, Huashan Lin, Xiaoping Yu
BackgroundPulmonary sclerosing pneumocytoma (PSP) and pulmonary carcinoid (PC) are difficult to distinguish based on conventional imaging examinations. In recent years, radiomics has been used to discriminate benign from malignant pulmonary lesions. However, the value of radiomics based on computed tomography (CT) images to differentiate PSP from PC has not been well explored.PurposeWe aimed to investigate
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Dosimetry of Large Field Valencia applicators for Cobalt‐60‐based brachytherapy Med Phys (IF 3.8) Pub Date : 2024-03-20 Gustavo H. Píriz, Gabriel A. Gonzalez‐Sprinberg, Facundo Ballester, Javier Vijande
BackgroundNon‐melanoma skin cancer is one of the most common types of cancer and one of the main approaches is brachytherapy. For small lesions, the treatment of this cancer with brachytherapy can be done with two commercial applicators, one of these is the Large Field Valencia Applicators (LFVA).PurposeThe aim of this study is to test the capabilities of the LFVA to use clinically 60Co sources instead
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First measurements of radon‐220 diffusion in mice tumors, towards treatment planning in diffusing alpha‐emitters radiation therapy Med Phys (IF 3.8) Pub Date : 2024-03-20 Guy Heger, Mirta Dumančić, Ishai Luz, Maayan Vatarescu, Noam Weizman, Brian W. Miller, Tomer Cooks, Lior Arazi
BackgroundDiffusing alpha‐emitters radiation therapy (“Alpha‐DaRT”) is a new method for treating solid tumors with alpha particles, relying on the release of the short‐lived alpha‐emitting daughter atoms of radium‐224 from interstitial sources inserted into the tumor. Alpha‐DaRT tumor dosimetry is governed by the spread of radium's progeny around the source, as described by an approximate framework
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A comprehensive investigation of the performance of a commercial scintillator system for applications in electron FLASH radiotherapy Med Phys (IF 3.8) Pub Date : 2024-03-20 Kevin Liu, Shannon Holmes, Emil Schüler, Sam Beddar
BackgroundDosimetry in ultra‐high dose rate (UHDR) beamlines is significantly challenged by limitations in real‐time monitoring and accurate measurement of beam output, beam parameters, and delivered doses using conventional radiation detectors, which exhibit dependencies in ultra‐high dose‐rate (UHDR) and high dose‐per‐pulse (DPP) beamline conditions.PurposeIn this study, we characterized the response
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Technical note: A universal worksheet for failure mode and effects analysis—A project of the Japanese College of Medical Physics Med Phys (IF 3.8) Pub Date : 2024-03-20 Shie Nishioka, Hiroyuki Okamoto, Takahito Chiba, Satoshi Kito, Yoshitomo Ishihara, Masaru Isono, Tomohiro Ono, Asumi Mizoguchi, Norifumi Mizuno, Naoki Tohyama, Masahiko Kurooka, Seiichi Ota, Daisuke Shimizu
BackgroundFailure mode and effects analysis (FMEA), which is an effective tool for error prevention, has garnered considerable attention in radiotherapy. FMEA can be performed individually, by a group or committee, and online.PurposeTo meet the needs of FMEA for various purposes and improve its accessibility, we developed a simple, self‐contained, and versatile web‐based FMEA risk analysis worksheet
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Deep learning‐based target decomposition for markerless lung tumor tracking in radiotherapy Med Phys (IF 3.8) Pub Date : 2024-03-20 Yabo Fu, Pengpeng Zhang, Qiyong Fan, Weixing Cai, Hai Pham, Andreas Rimner, John Cuaron, Laura Cervino, Jean M. Moran, Tianfang Li, Xiang Li
BackgroundIn radiotherapy, real‐time tumor tracking can verify tumor position during beam delivery, guide the radiation beam to target the tumor, and reduce the chance of a geometric miss. Markerless kV x‐ray image‐based tumor tracking is challenging due to the low tumor visibility caused by tumor‐obscuring structures. Developing a new method to enhance tumor visibility for real‐time tumor tracking
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Nonunion scaphoid bone shape prediction using iterative kernel principal polynomial shape analysis Med Phys (IF 3.8) Pub Date : 2024-03-18 Junjun Zhu, Junhao Zhao, Xianggeng Luo, Zikai Hua
BackgroundThe scaphoid is an important mechanical stabilizer for both the proximal and distal carpal columns. The precise estimation of the complete scaphoid bone based on partial bone geometric information is a crucial factor in the effective management of scaphoid nonunion. Statistical shape model (SSM) could be utilized to predict the complete scaphoid shape based on the defective scaphoid. However
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First Monte Carlo beam model for ultra‐high dose rate radiotherapy with a compact electron LINAC Med Phys (IF 3.8) Pub Date : 2024-03-17 Tianyuan Dai, Austin M. Sloop, Mahbubur R. Rahman, Jacob P. Sunnerberg, Megan A. Clark, Ralph Young, Sebastian Adamczyk, Philip Von Voigts‐Rhetz, Chris Patane, Michael Turk, Lesley Jarvis, Brian W. Pogue, David J. Gladstone, Petr Bruza, Rongxiao Zhang
BackgroundFLASH radiotherapy based on ultra‐high dose rate (UHDR) is actively being studied by the radiotherapy community. Dedicated UHDR electron devices are currently a mainstay for FLASH studies.PurposeTo present the first Monte Carlo (MC) electron beam model for the UHDR capable Mobetron (FLASH‐IQ) as a dose calculation and treatment planning platform for preclinical research and FLASH‐radiotherapy
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A comprehensive lung CT landmark pair dataset for evaluating deformable image registration algorithms Med Phys (IF 3.8) Pub Date : 2024-03-13 Edward R. Criscuolo, Yabo Fu, Yao Hao, Zhendong Zhang, Deshan Yang
PurposeDeformable image registration (DIR) is a key enabling technology in many diagnostic and therapeutic tasks, but often does not meet the required robustness and accuracy for supporting clinical tasks. This is in large part due to a lack of high‐quality benchmark datasets by which new DIR algorithms can be evaluated. Our team was supported by the National Institute of Biomedical Imaging and Bioengineering
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Adapting low‐dose CT denoisers for texture preservation using zero‐shot local noise‐level matching Med Phys (IF 3.8) Pub Date : 2024-03-13 Youngjun Ko, Seongjong Song, Jongduk Baek, Hyunjung Shim
BackgroundOn enhancing the image quality of low‐dose computed tomography (LDCT), various denoising methods have achieved meaningful improvements. However, they commonly produce over‐smoothed results; the denoised images tend to be more blurred than the normal‐dose targets (NDCTs). Furthermore, many recent denoising methods employ deep learning(DL)‐based models, which require a vast amount of CT images
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Quantitative measurement of the ureter on three‐dimensional magnetic resonance urography images using deep learning Med Phys (IF 3.8) Pub Date : 2024-03-13 Rile Nai, Kexin Wang, Xiaoqing Li, Shangsong Du, Tuya E, He Xiao, Shuo Quan, Yaofeng Zhang, Junhua Yu, Jialun Li, Xiaodong Zhang, Xiaoying Wang
BackgroundAccurate measurement of ureteral diameters plays a pivotal role in diagnosing and monitoring urinary tract obstruction (UTO). While three‐dimensional magnetic resonance urography (3D MRU) represents a significant advancement in imaging, the traditional manual methods for assessing ureteral diameters are characterized by labor‐intensive procedures and inherent variability. In the realm of