Yunjie Yang, Donghoon Lee, Matthew Whitaker, Wendy Harris, Jeho Jeong, Shih-Chi Lin, Ellen Yorke, Lakshmi Santanam, Grace Tang
{"title":"A streamlined workflow for comprehensive 4DCT imaging QA with automated analysis of spatial integrity and image quality","authors":"Yunjie Yang, Donghoon Lee, Matthew Whitaker, Wendy Harris, Jeho Jeong, Shih-Chi Lin, Ellen Yorke, Lakshmi Santanam, Grace Tang","doi":"10.1002/acm2.70168","DOIUrl":"https://doi.org/10.1002/acm2.70168","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>A comprehensive 4DCT QA program that includes the assessment of spatial integrity and image quality of 4D phantom scans can be resource-intensive, especially because the analysis burden scales with the number of motion traces used for QA. This work presents a streamlined and scalable workflow, enabled by the use of a widely available phantom and an automated analysis tool.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>For 4DCT imaging QA, the Catphan was placed on the QUASAR motion platform, driven with sinusoidal motion traces of various amplitudes and frequencies. The acquired image sets were automatically analyzed using a newly designed 4DCT analysis module in TotalQA. The metrics of interest for 4DCT QA were analyzed for image sets of all motion bins and compared to the stationary reference image set. Three broad categories of imaging tests for 4DCT QA were defined: spatial integrity, HU constancy, and image quality. The sensitometry plugs in the Catphan were used as motion surrogates for evaluating spatial integrity, including the dimensions of the plugs and the observed motion amplitude in the scans. HU values of the sensitometry plugs in different phases were evaluated for consistency. For image quality, spatial resolution, low contrast resolution, and image noise were evaluated.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Compared to the stationary reference CT, spatial integrity was within ±1 mm and the HU values were within two HU in the 4DCT for all phases. The spatial resolution was consistent while slightly higher noise was observed in the 4DCT images. The automated analysis in TotalQA was completed in approximately 20 min per motion trace, improving efficiency by more than 80% compared to the manual workflow.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>A streamlined 4DCT imaging QA workflow with automated analysis offers a robust assessment of imaging quality and motion accuracy in 4DCT scans, enabling an efficient and consistent QA process in large healthcare networks.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70168","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144714700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Non-compliant neutron dose associated with an internal lead slab in a radiotherapy treatment vault","authors":"Eduardo Galiano, Camila Salata, Marcelo Godin","doi":"10.1002/acm2.70182","DOIUrl":"https://doi.org/10.1002/acm2.70182","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>In high energy radiotherapy treatment vaults, photoneutrons can be produced by direct photon interactions with barrier materials and have a mean energy of approximately 20% of the nominal photon energy. Excess photoneutrons outside a treatment vault are always a concern due to their significant radiobiological efficacy, or Q value.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A pre-clinical regulatory inspection of a newly installed linear accelerator detected legally non-compliant photoneutron dose levels in a controlled area outside the treatment vault. The non-compliant dose was measured for a 10 MV photon beam external to the primary barrier improperly containing an internal 2.0 cm lead slab.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Based on measurements at a photon energy of 10 MV, using a workload <i>W</i> = 1500 Gy/week, a use factor of <i>U</i> = 1, and an occupancy factor of <i>T </i>= 0.5—which are NCRP-151 recommended values—an equivalent neutron weekly dose of 443 ± 38 µSv was calculated for a point in a controlled area external to the vault (point A in Figure 1). This results in a calculated annual neutron dose at this point of 22.1 ± 2.2 mSv, which exceeds the legal occupational annual limit of 20 mSv for a controlled area in our jurisdiction. The lead slab was removed. Neutron measurements taken subsequent to the removal of the slab detected values slightly above natural background.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The probable source of the non-compliant neutron dose outside the treatment vault was the presence of the lead slab.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70182","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to “Dosimetric characteristics of LinaTech DMLC H multi leaf collimator: Monte Carlo simulation and experimental study”","authors":"","doi":"10.1002/acm2.70155","DOIUrl":"https://doi.org/10.1002/acm2.70155","url":null,"abstract":"<p>Molazadeh M, Zeinali A, Robatjazi M, Shirazi A, Geraily G. Dosimetric characteristics of LinaTech DMLC H multi leaf collimator: Monte Carlo simulation and experimental study. <i>J Appl Clin Med Phys</i>. 2017;18(2):113-124.</p><p>In paragraph 1 of the “ACKNOWLEDGMENTS” section, the text “This research was supported by the vice-chancellor of research at Tehran University of Medical Sciences and Health Services (grant number 28202).” was incorrect and the code of ethics has been forgotten. This should have read: “This research was supported by the vice-chancellor of research at Tehran University of Medical Sciences and Health Services (grant number 28202, Ethic code: IR.TUMS.REC.1394.164).” The online version of this article has been corrected accordingly.</p><p>We apologize for this error.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70155","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yao Xiao, Yan Zhuang, Wenwu Ling, Shouyu Jiang, Ke Chen, Guoliang Liao, Yuhua Xie, Yao Hou, Lin Han, Zhan Hua, Yan Luo, Jiangli Lin
{"title":"LGF-Net: A multi-scale feature fusion network for thyroid nodule ultrasound image classification","authors":"Yao Xiao, Yan Zhuang, Wenwu Ling, Shouyu Jiang, Ke Chen, Guoliang Liao, Yuhua Xie, Yao Hou, Lin Han, Zhan Hua, Yan Luo, Jiangli Lin","doi":"10.1002/acm2.70149","DOIUrl":"https://doi.org/10.1002/acm2.70149","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Thyroid cancer is one of the most common cancers in clinical practice, and accurate classification of thyroid nodule ultrasound images is crucial for computer-aided diagnosis. Models based on a convolutional neural network (CNN) or a transformer struggle to integrate local and global features, which impacts the recognition accuracy.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>Our method is designed to capture both the key local fine-grained features and the global spatial features essential for thyroid nodule diagnosis simultaneously. It adapts to the irregular morphology of thyroid nodules, dynamically focuses on the key pixel-level regions of thyroid nodules, and thereby improves the model's recognition accuracy and generalization ability.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The proposed multi-scale fusion model, the local and global feature fusion network (LGF-Net), inspired by the dual-path mechanism of human visual diagnosis, consists of two branches: a CNN branch and a Transformer branch. The CNN branch integrates the wavelet transform and deformable convolution module (WTDCM) to enhance the model's ability to capture discriminative local features and recognize fine-grained textures. By introducing the aggregated attention (AA) mechanism, which mimics biological vision, into the Transformer branch, spatial features are effectively captured. The adaptive feature fusion module (FFM) is then utilized to integrate the multi-scale features of thyroid nodules, further improving classification performance.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>We evaluated our model on the public thyroid nodule classification dataset (TNCD) and a private clinical dataset using accuracy, recall, precision, and F1-score. On TNCD, the model achieved 81.50%, 79.51%, 79.92%, and 79.70%, respectively. On the private dataset, it reached 91.24%, 88.90%, 90.73%, and 89.73%, respectively. These results outperformed state-of-the-art methods. We also conducted ablation studies and visualization analysis to validate the model's components and interpretability.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The experiments demonstrate that our method improves the accuracy of thyroid nodule recognition, shows its strong generalization ability and potential for clinical application, and provides interpretability for clinicians' diagnoses.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70149","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kenneth W. Gregg, Theodore Arsenault, Atefeh Rezaei, Rojano Kashani, Lauren Henke, Alex T Price
{"title":"Hounsfield Unit characterization and dose calculation on a C-arm linac with novel on-board cone-beam computed tomography feature and advanced reconstruction algorithms","authors":"Kenneth W. Gregg, Theodore Arsenault, Atefeh Rezaei, Rojano Kashani, Lauren Henke, Alex T Price","doi":"10.1002/acm2.70145","DOIUrl":"https://doi.org/10.1002/acm2.70145","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>Current cone-beam computed tomography (CBCT) on-board c-arm linear accelerators (linacs) lack CT number precision sufficient for dose calculation due to increased scatter from the cone geometry. This investigation evaluated CT number and dose calculation accuracy in-phantom on a novel on-board CBCT unit with potential for improved dose calculation accuracy.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Eight head and eight body configurations of an electron density phantom using 16 materials were acquired with a clinical CT-simulator(CT-sim) and novel on-board CBCT imager. CBCT projection data was reconstructed using conventional Feldkamp–Davis–Kress(FDK) and patient scatter-corrected iterative Acuros CTS with metal artifact reduction (Acuros-CTS-iCBCT-MAR) to create a robust CT number to physical density curve. CT-sim and CBCT images of anthropomorphic head and thorax phantoms were acquired, and three treatment plans were generated per phantom. All CBCT images were registered to the CT-sim of the phantoms, and the dose was recalculated on the CBCT images. 3D gamma analysis was performed (10% dose threshold, local, 1% dose difference, 1 or 2 mm distance to agreement), and dose–volume histogram (DVH) metrics were reported for target coverage and organ sparing.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>CT numbers for materials ≤1.08 g/cc showed high agreement between CT-sim and CBCT acquisitions. CT number precision improved with Acuros-CTS-iCBCT-MAR compared to FDK in all materials. High agreement between CT-sim and CBCT reconstructed with Acuros-CTS-iCBCT-MAR was observed in 3D gamma analysis showing 93.8% voxels passing in the worst case for a spine stereotactic body radiotherapy (SBRT) plan at 1%/1 mm. Maximum deviation in target coverage was −3.3% PTV-D98% in the lung SBRT plan among the novel reconstructed CBCT images. Plan comparison using FDK reconstructions yielded similar or worse agreement in 3D gamma analysis, with 69.7% voxels passing in the worst case for a spine SBRT treatment plan. Maximum target coverage deviation was −11.7% PTV-D98% among the FDK-reconstructed CBCT.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Novel CBCT solutions on c-arm linacs show promise for enabling direct-to-unit or offline adaptive dose calculation, potentially increasing versatility and efficiency of patient-centered care.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70145","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Naonori Hu, Taiki Nakamura, Ryusuke Kataura, Keita Suga, Tetsuya Mukawa, Kazuhiko Akita, Ryo Kakino, Akinori Sasaki, Mai Nojiri, Nishiki Matsubayashi, Takushi Takata, Hiroki Tanaka, Keiji Nihei, Koji Ono
{"title":"Implementation of a real-time neutron monitor system for use in routine quality assurance of an accelerator-based neutron system for clinical boron neutron capture therapy","authors":"Naonori Hu, Taiki Nakamura, Ryusuke Kataura, Keita Suga, Tetsuya Mukawa, Kazuhiko Akita, Ryo Kakino, Akinori Sasaki, Mai Nojiri, Nishiki Matsubayashi, Takushi Takata, Hiroki Tanaka, Keiji Nihei, Koji Ono","doi":"10.1002/acm2.70190","DOIUrl":"https://doi.org/10.1002/acm2.70190","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Currently, the metal foil activation method is routinely used to measure the neutron output of an accelerator-based neutron source designed for clinical Boron neutron capture therapy (BNCT). Although this method is well established and has been primarily utilized since the nuclear reactor BNCT era, the process is labour-intensive and not well-suited for a busy hospital environment performing routine patient treatment. A replacement neutron detector system that is simple to use and can measure the neutron output in real-time is necessary.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>Investigation and implementation of an Eu doped LiCaAlF<sub>6</sub> scintillator detector for use in routine quality assurance tests of an accelerator-based neutron source designed for clinical BNCT.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The response of the scintillator detector was evaluated using the NeuCure BNCT system installed at the Kansai BNCT Medical Center. The measurement repeatability, neutron fluence linearity, and neutron flux dependency of the detector system were evaluated. The beam central axis and off-axis thermal neutron distribution inside a water phantom were measured and compared with the Monte Carlo treatment planning system (TPS).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The scintillator detector system showed high measurement repeatability with a coefficient of variation of less than 0.4%. The detector system showed linear response up to a proton charge of 3.6 C, and the response was stable between a proton current of 0.1 and 1 mA. Both the central axis and off-axis thermal neutron flux inside a water phantom matched closely with both the metal foil activation method and the Monte Carlo simulation results. The time it took to perform a routine quality assurance test was drastically reduced from 1.5 h down to a few minutes.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Implementation of this detector system in the clinic would significantly reduce the time required for routine QA, acceptance, and commissioning, and be a stepping stone to assist expansion of accelerator-based BNCT systems worldwide.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70190","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stefania Linsalata, Jake H. Pensavalle, Franco Perrone, Patrizio Barca, Fabio Di Martino, Fabiola Paiar, Antonio C. Traino
{"title":"Classification performances of two diode arrays for patient-specific quality assurance of stereotactic body radiation therapy treatments based on absolute dose measurements in phantom","authors":"Stefania Linsalata, Jake H. Pensavalle, Franco Perrone, Patrizio Barca, Fabio Di Martino, Fabiola Paiar, Antonio C. Traino","doi":"10.1002/acm2.70167","DOIUrl":"https://doi.org/10.1002/acm2.70167","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Despite the rapid growth in the clinical practice, no specific recommendations on pre-treatment patient-specific quality assurance of volumetric modulated arc therapy-based stereotactic body radiation therapy plans have been established.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>In this contest, the study aims to identify optimal gamma analysis criteria and thresholds for the Sun Nuclear ArcCHECK and SRS MapCHECK arrays.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Twenty SBRT plans were delivered on both devices per plan and field-by-field. The measurements were compared with calculations and Gamma Passing Rates (GPRs), obtained using global normalization in absolute dose and 10% threshold, with six different Dose Difference (DD) / Distance To Agreement (DTA) criteria stricter than those universally suggested by the Report of the AAPM Task Group No. 218, were recorded. Receiver Operating Characteristics analysis was performed on GPRs while varying the threshold from 0% to 100%, the agreement between calculations and absolute dose measurements, obtained with a IBA Razor chamber at the isocenter in phantom at different levels (i.e., 1%, 2%, 3%, 4%, and 5%), being the Ground Truth. Significance of the resulting Areas Under Curve (AUCs) against the random guess was tested.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>AUCs obtained with ArcCHECK are generally more significant than with SRS MapCHECK, while those measured field-by-field are more significant than per plan. Within the considered DD/DTA criteria, the most discriminative ones are device-specific, that is, 2%/2 mm or 1%/2 mm for ArcCHECK and 2%/1 mm or 1%/1 mm for SRS MapCHECK.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Our results on ArcCHECK confirm the indication of the AAPM Task Group No. 218, while for SRS MapCHECK, acceptable discriminating capabilities are possible with DTA = 1 mm, suggesting that devices with native higher spatial resolution, preferred in SBRT for the better sampling of the dose distribution, require tighter DTA.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70167","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. N. Malkov, B. J. Kemp, A. Ferrero, L. Buchholtz, S. S. Park, J. A. Kavanaugh
{"title":"Adaptive-driven CT simulation-free multi-fraction SBRT radiotherapy: Initial clinical experience","authors":"V. N. Malkov, B. J. Kemp, A. Ferrero, L. Buchholtz, S. S. Park, J. A. Kavanaugh","doi":"10.1002/acm2.70147","DOIUrl":"https://doi.org/10.1002/acm2.70147","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Introduction</h3>\u0000 \u0000 <p>Using diagnostic CT for radiotherapy (RT) planning can bypass traditional CT simulation but introduces challenges in patient positioning and Hounsfield unit (HU) fidelity, affecting dose accuracy. Here a Varian Ethos adaptive-driven CT direct-to-treatment (DtT) multi-fraction stereotactic body radiation therapy (SBRT) workflow is presented.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>This study employed institutional diagnostic PET-CT images to generate an initial reference Ethos treatment plan. HU and dosimetric accuracy were validated for PET-CT, Ethos CBCT images (with and without Hypersight (HS), and the gold-standard helical CT simulators). Following the SBRT reference plan creation on the low dose diagnostic PET-CT, the first fraction was delivered with a newly generated adaptive plan calculated on the HS CBCT (Ethos) images. For multi-fraction treatments, the first day CBCT images and adaptive plan become the reference for subsequent IGRT treatments. This study includes workflow validation and initial three patient experience.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The DtT adaptive SBRT workflow was successfully implemented, with initial end-to-end testing demonstrating feasibility. In-house solutions were introduced to facilitate the adaptive to IGRT plan conversion. The Ethos system, especially with HS, maintained HU fidelity and dose calculation accuracy comparable to helical CTs. On-table adaptive sessions were within 37–51 min, aligning with single-fraction palliative studies. Subsequent non-adaptive IGRT fractions were efficiently completed within 7–27 min.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study demonstrates the feasibility of DtT adaptive-driven multifraction SBRT using diagnostic PET-CT. This approach reduces the need for on-site patient presence prior to treatment, expands planning lead times, and improves overall efficiency in radiotherapy for well selected patients.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70147","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144705320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Trishul Siddharthan, Zhoubing Xu, Bruce Spottiswoode, Chris Schettino, Yoel Siegel, Michalis Georgiou, Thomas Eluvathingal, Bernhard Geiger, Sasa Grbic, Partha Gosh, Rachid Fahmi, Naresh Punjabi
{"title":"A multi-stage 3D convolutional neural network algorithm for CT-based lung segment parcellation","authors":"Trishul Siddharthan, Zhoubing Xu, Bruce Spottiswoode, Chris Schettino, Yoel Siegel, Michalis Georgiou, Thomas Eluvathingal, Bernhard Geiger, Sasa Grbic, Partha Gosh, Rachid Fahmi, Naresh Punjabi","doi":"10.1002/acm2.70193","DOIUrl":"https://doi.org/10.1002/acm2.70193","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Current approaches to lung parcellation utilize established fissures between lobes to provide estimates of lobar volume. However, deep learning segment parcellation provides the ability to better assess regional heterogeneity in ventilation and perfusion.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>We aimed to validate and demonstrate the clinical applicability of CT-based lung segment parcellation using deep learning on a clinical cohort with mixed airways disease.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Using a 3D convolutional neural network, airway centerlines were determined using an image-to-image network. Tertiary bronchi were identified on top of the airway centerline, and the pulmonary segments were parcellated based on the spatial relationship with tertiary and subsequent bronchi. The data obtained by following this workflow was used to train a neural network to enable end-to-end lung segment parcellation directly from 123 chest CT images. The performance of the parcellation network was then evaluated quantitatively using expert-defined reference masks on 20 distinct CTs from the training set, where the Dice score and inclusion rate (i.e., percentage of the detected bronchi covered by the correct segment) between the manual segmentation and automatic parcellation results were calculated for each lung segment. Lastly, a qualitative evaluation of external validation was performed on 20 CTs prospectively collected by having two radiologists review the parcellation accuracy in healthy individuals (<i>n</i> = 10) and in patients with chronic obstructive pulmonary disease (COPD) (<i>n</i> = 10).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Means and standard deviation of Dice score and inclusion rate between automatic and manual segmentation of twenty patient CTs were 86.81 (SD = 24.54) and 0.75 (SD = 0.19), respectively, across all lung segments. The mean age of the qualitative dataset was 54.4 years (SD = 16.4 years), with 45% (<i>n</i> = 9) women. There was 99.2% intra-reader agreement on average with the produced segments. Individuals with COPD had greater mismatch compared to healthy controls.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>A deep-learning algorithm can create parcellation masks from chest CT scans, and the quantitative and qualitative evaluations yielded encouraging results for the potential clinical usage of lung analysis at the pulmonary segment level among those with s","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 8","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70193","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144681309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Broderick Ivan McCallum-Hee, Mounir Ibrahim, Godfrey Mukwada, Pejman Rowshanfarzad, Joshua Dass, Jude Dewitt, Robert Parin, Gregory Withey, Zaid Alkhatib
{"title":"Commissioning and clinical implementation of low dose dual-field rotational TSET","authors":"Broderick Ivan McCallum-Hee, Mounir Ibrahim, Godfrey Mukwada, Pejman Rowshanfarzad, Joshua Dass, Jude Dewitt, Robert Parin, Gregory Withey, Zaid Alkhatib","doi":"10.1002/acm2.70180","DOIUrl":"https://doi.org/10.1002/acm2.70180","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Total skin electron therapy (TSET) is a specialized technique for treating cutaneous T-cell lymphomas, such as mycosis fungoides. While traditional TSET regimens prescribe 30–36 Gy, low dose TSET at 12 Gy has gained attention due to its reduced toxicity. The dual-field rotational TSET technique, utilizing a standard linac, offers a practical solution for improved dose distribution. However, limited studies exist on its commissioning and clinical implementation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>This study aimed to commission and clinically implement a low dose dual-field rotational TSET technique. The primary objectives were to optimize beam geometry, characterize dosimetry, and ensure treatment uniformity while maintaining compliance with ACPSEM, EORTC, and AAPM guidance.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A Varian TrueBeam linac equipped with a 6 MeV high-dose-rate total skin electron beam was commissioned for TSET. Dosimetric measurements included beam output calibration, relative dosimetry, and dose uniformity assessment using an ion chamber and Gafchromic film, with verification using an anthropomorphic phantom. A treatment dose calculation methodology was developed. Shielding, ozone generation, and quality assurance were assessed. In vivo dosimetry was performed for treatment validation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The optimal dual-field beam geometry was determined to be ± 18° from the horizontal, achieving vertical uniformity within ± 2.9% and an overall treatment plane uniformity of ± 8.6%. Under rotation, the depth dose is delivered 100% at the surface, with bremsstrahlung contamination of 0.2 Gy. Custom eye shielding was developed, and ozone concentrations remained below the NCRP 0.1 parts per million (ppm) safety thresholds. In vivo dosimetry confirmed treatment uniformity within EORTC guidelines and identified three regions requiring dose boosts: the shoulders, palms, and inner thighs.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The commissioned dual-field rotational TSET technique provides a viable treatment option, achieving clinically acceptable dose distribution.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70180","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144624325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}