Journal of Applied Clinical Medical Physics最新文献

{"title":"Evaluation of the effect of metal stents on dose perturbation in the carbon beam irradiation field.","authors":"Yuya Miyasaka, Tetsuya Ishizawa, Yoshihito Nawa, Hikaru Souda, Shohei Kawashiro, Hongbo Chai, Miyu Ishizawa, Hiraku Sato, Takeo Iwai","doi":"10.1002/acm2.70042","DOIUrl":"https://doi.org/10.1002/acm2.70042","url":null,"abstract":"<p><strong>Propose: </strong>Carbon ion therapy is indicated for cases in which stents have been inserted, such as bile ducts, but the effect of metal stents on carbon ion therapy is unclear. In this study, the dose perturbation of carbon ion therapy caused by metallic bile duct stents was evaluated by dosimetry.</p><p><strong>Materials and methods: </strong>Five different types of metal stents (EGIS Double Bear Biliary Stent, EGIS Single Bear Covered Biliary Stent, BileRush Selective, Niti-S Less Shortening D-type Stent, and ZEO Stent V) were placed between solid phantoms and Gafchromic film were placed around the stents and at each depth. The phantom was irradiated with a Carbon ion Beam to form a 5 cm × 5 cm × 5 cm spread-out Brag peak. The dose change due to the stent was evaluated by comparing the film values of similar irradiations without the stent in place.</p><p><strong>Result: </strong>The results showed that the dose perturbation with and without the stent was <10%. A dose reduction area along the shape of the stent appeared at the end of the irradiation field.</p><p><strong>Conclusion: </strong>The effect of metal stents on the carbon dose distribution was assumed to be comparable to that of x-rays and protons.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70042"},"PeriodicalIF":2.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143448567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of enhanced leaf model on dose calculation accuracy in single-isocenter multitarget stereotactic radiosurgery treatments.","authors":"Hem Moktan, Hongyu Jiang, H Harold Li, Kenny Guida","doi":"10.1002/acm2.70039","DOIUrl":"https://doi.org/10.1002/acm2.70039","url":null,"abstract":"<p><strong>Purpose: </strong>Single-isocenter multitarget (SIMT) radiosurgery has become increasingly popular as advancement in planning and delivery systems have made this approach clinically viable. With targets varying in size and distance from isocenter, SIMT plans are highly complex with dynamic multileaf collimator (MLC) motion. Our department recently commissioned Eclipse Treatment Planning System v18.0, which included a novel enhanced leaf model (ELM) for photon dose calculation. ELM represents the biggest update in MLC modeling on a commercial treatment planning system over the past decade, yielding improvements in leaf modeling and ray tracing. Considering its dependence on dynamic MLC movements, we set out to assess the potential clinical impact of ELM on SIMT.</p><p><strong>Methods: </strong>Dynamic zebra crosswalk (DZC) plans were delivered on a Varian Edge to investigate ELM. DZCs consisted of sweeping MLC gaps (ranging 1-15 mm) across a 3 cm width at isocenter, 4 cm, 8 cm, and 12 cm along the x-axis. Phantom dose calculations were performed using AAA v15.6 and v18.0 (with ELM) for 6 MV flattening filter free DZC plans and compared to measurements using stereotactic radiosurgery MapCHECK (Sun Nuclear Corporation) and Gafchromic EBT4 films (Ashland). To assess potential impact on SIMT, ten patients were retrospectively planned with RapidArc and HyperArc. Both versions of AAA were used for dose calculation.</p><p><strong>Results: </strong>DZC measurements showed improved agreement with ELM; differences between measured and calculated doses were reduced by as much as 19% for the smallest sweeping gaps at off-axis distances. Differences in central profile dose for DZCs increased with reduced gap size and increased off-axis position. SIMT plans showed up to 4.0% increase in planning target volume (PTV) maximum dose when switching from AAA v15.6 to v18.0.</p><p><strong>Conclusion: </strong>Dose calculations with ELM mirrored diode and film measurements for highly modulated SIMT plans. ELM represents a major improvement in MLC modeling that more accurately reflects current treatment delivery practice.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70039"},"PeriodicalIF":2.0,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143458001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feasibility study of skin dosimetry with TLD sheets for measuring the effect of 3D printed bolus in radiotherapy.","authors":"Yuya Miyasaka, Mayumi Ichikawa, Takagi Akira, Yoshifumi Yamazawa, Hongbo Chai, Hikaru Souda, Miyu Ishizawa, Hiraku Sato, Takeo Iwai","doi":"10.1002/acm2.70035","DOIUrl":"https://doi.org/10.1002/acm2.70035","url":null,"abstract":"<p><p>The thermoluminescence dosimeter (TLD) sheet is a measurement device coated with manganese-doped LiB₃O₅ in sheet form. The sheet is 0.2-mm thick and flexible. Hence, it can fit and be installed on irregular surfaces. The current study aimed to evaluate the feasibility of measuring patient surface doses during radiation therapy using TLD sheets. Further, the surface doses when using a three-dimensional (3D) printed bolus were compared. First, calibration of the between TLD sheet measurements and the irradiation doses was performed. Second, dose calculations and TLD sheet measurements were compared to evaluate the error between treatment planning system (TPS) dose calculations and surface dose measurements. Finally, the TLD sheet was fitted to the head phantom to measure the surface dose at the uneven areas under two conditions (with a commercial [CM] bolus and a 3D-printed bolus). Based on the error from the dose calculation algorithm and the difference between the TLD sheet thickness and the dose grid size or evaluation structure volume, the differences between the TLD sheet measurements and the treatment plan doses were up to 68.6% for the X-ray collapsed cone convolution (CCC) method and up to 8.4% for the electron beam Monte Carlo (MC) method. Based on the results of the surface dosimetry of the head phantom, the application of surface dosimetry, particularly skin dosimetry, even on uneven body surfaces, can be feasible.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70035"},"PeriodicalIF":2.0,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143441102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IROC phantoms accurately detect MLC delivery errors.","authors":"Sharbacha S Edward, Julianne M Pollard-Larkin, Peter A Balter, Rebecca M Howell, Christine B Peterson, Stephen F Kry","doi":"10.1002/acm2.70017","DOIUrl":"https://doi.org/10.1002/acm2.70017","url":null,"abstract":"<p><strong>Purpose: </strong>We evaluated the impact of random and whole-bank multileaf collimator (MLC) delivery errors on dosimetric delivery accuracy in the Imaging and Radiation Oncology Core (IROC) phantom audits, as well as differences in delivery accuracy between the IROC phantom prescription and typical clinical fraction sizes.</p><p><strong>Methods and materials: </strong>Plans were created for the IROC IMRT head and neck (H&N) and SBRT spine phantoms. MLC leaf errors were introduced into the plans: random shifts between -2 and 2 mm, and whole bank shifts of 0.5, 1, and 2 mm. Plans were recalculated and delivered on a Varian Truebeam, and the log files were analyzed using Mobius Fx software. A second study examined the impact of fraction size on MLC position accuracy and corresponding dose delivery accuracy. The standard IROC phantom prescriptions (∼6 Gy) were scaled to the extremes of 2 Gy for H&N and 27 Gy for spine. All plans (original and scaled) were delivered on a Varian Truebeam and 21EX machine.</p><p><strong>Results: </strong>Random MLC positioning errors produced small average dose deviations in the PTV of up to -2.8% for H&N and 0.7% for spine. Whole-bank MLC shifts resulted in larger average PTV dose deviations up to 8% for H&N and 7.1% for spine. The Varian 21EX irradiations had greater MLC root mean square (RMS) error than Truebeam plans. Plans with smaller prescriptions (and faster leaf motion) had greater MLC RMS errors, but plan accuracy was not affected dosimetrically - all results remained within 1% regardless of fraction size.</p><p><strong>Conclusions: </strong>Both random and whole bank MLC shifts caused dose deviations in the IROC phantoms that were comparable to clinical results previously found in the literature. Deviations measured with ion chambers were well matched with delivery log file analysis. Smaller dose-per-fraction prescriptions caused larger MLC RMS errors that were detected with log files, but were clinically insignificant compared to the dosimetric accuracy of the plan.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70017"},"PeriodicalIF":2.0,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143448814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the dose reduction effect of crystalline lens exposure in cone-beam computed tomography with bismuth eye shield for image-guided radiation therapy: An anthropomorphic phantom study.","authors":"Tatsuya Yoshida, Koji Sasaki, Yoshiyuki Kawasaki, Tomoki Hayakawa, Toshiyuki Kawadai, Takako Shibasaki","doi":"10.1002/acm2.70024","DOIUrl":"https://doi.org/10.1002/acm2.70024","url":null,"abstract":"<p><p>This study aimed to evaluate the dose-exposure reduction effect of a crystalline lens with a bismuth eye shield using cone-beam computed tomography (CBCT) for head image-guided radiation therapy. The ocular surface dose of the head phantom (THRA-1) is defined as a crystalline lens exposure dose and is measured using a radiophotoluminescence dosimeter (RPLD, GD-352 M) with and without an eye shield (CT eye shield) while moving the head phantom from the reference position that is set at the center of the head in either the X or Z direction from -5 to +5 cm. The exposure doses were measured thrice at each movement position. The crystalline lens exposure doses at the reference position were 0.896 ± 0.024 mGy and 0.892 ± 0.016 mGy for the right and left sides, respectively. The exposure doses at the position where the head phantom was moved 5 cm in the -Z direction from the reference position were 2.812 ± 0.053 mGy and 2.576 ± 0.038 mGy for the right and left sides, respectively, with the highest doses at all movement positions. The crystalline lens exposure doses were reduced to 1.909 ± 0.046 mGy and 1.768 ± 0.043 mGy for the right and left sides with an eye shield in this position, causing an exposure dose reduction rate of -32% and -31%, respectively. The crystalline lens exposure dose reduction rate was approximately 10%-15% in the movement directions, except for the -Z direction. Head CBCT with an eye shield effectively reduced the crystalline lens exposure dose when the CBCT isocenter was set close to the eye. Head CBCT using an eye shield is a useful method that reduces the crystalline lens exposure dose.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70024"},"PeriodicalIF":2.0,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143448309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of OPTOS wide-field fundus image projections for radiotherapy planning of uveal melanoma","authors":"Jörg Wulff,&nbsp;Benjamin Koska,&nbsp;Michael Giese,&nbsp;Christian Bäumer,&nbsp;Ronald Richter,&nbsp;Andreas Foerster,&nbsp;Nikolaos E. Bechrakis,&nbsp;Beate Timmermann","doi":"10.1002/acm2.70009","DOIUrl":"10.1002/acm2.70009","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To investigate the relationship between the stereographic and azimuthal equidistant projection (AEP) of the human retina for radiotherapy planning with OPTOS optomap wide-field fundus images (Optos, UK). Further, the geometric accuracy of an OPTOS fundus image is quantified.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The fundamental relationship between both projection modes was applied to transform images acquired with an OPTOS Silverstone camera to the azimuthal equidistant projection using MATLAB. Fundus images of four patients were used to quantitatively demonstrate the impact for neglecting the proper projection. For that purpose, a delineated contour for each patient was analyzed if created in a treatment planning system, which assumes AEP, and compared with an OPTOS image. Furthermore, an eye model with a novel 3D printed retina pattern was used to quantify the geometric accuracy for an OPTOS optomap image.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The difference between both projections was found substantial, leading to a change in delineated contours of more than 5 mm in the investigated cases and a change of delineated area of more than 40%. The geometric accuracy of OPTOS images of a customized eye model was found to be 0.2 mm on average, increasing to at most ∼0.5 mm at eye angles of 81°.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The fundamental difference in the representation of the eye fundus needs to be accounted for in radiotherapy planning of uveal melanoma. The basic underlying relationship for transformation is known, but more research is required to quantify other aberrations. The novel use of 3D printed retina patterns with known dimensions is providing a flexible approach for further investigations.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 4","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143441098","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":"Commissioning of Halcyon enhanced leaf model in the Eclipse treatment planning system: Focus on simple slit fields and VMAT dose calculation.","authors":"Ryohei Miyasaka, Mari Shirai, Mitsunobu Igari, Yume Kojima, Yuki Kozawa, Toru Kawachi, Ryusuke Hara","doi":"10.1002/acm2.70044","DOIUrl":"https://doi.org/10.1002/acm2.70044","url":null,"abstract":"<p><strong>Purpose: </strong>The dual-layer multileaf collimator (MLC) in Halcyon adds complexities to the dose calculation process owing to the variability of dosimetric characteristics with leaf motion. Recently, an enhanced leaf model (ELM) was developed to refine the MLC model in the Eclipse treatment planning system. This study investigates the performance of the Halcyon ELM by verifying doses for simple slit fields and volumetric modulated arc therapy (VMAT) plans.</p><p><strong>Materials and methods: </strong>Dose calculations were performed with Acuros XB using the ELM. To commission the leaf-tip model, the dosimetric leaf gap (DLG) was calculated (referred to as DLG_ELM) and compared with Halcyon measurements. The DLGs were assessed under conditions both with and without leaf trailing between the MLC layers. The tongue-and-groove (TG) model was evaluated by comparing leaf-edge profiles and the outputs of the asynchronous sweeping gap. Furthermore, eleven VMAT plans were validated against chamber doses and Delta4 measurements.</p><p><strong>Results: </strong>DLG_ELM demonstrated variation between layers, measuring 0.42 mm for the proximal layer and 0.23 mm for the distal layer, and showed a correspondence with the measured DLGs in 0.1 mm. Additionally, ELM reduced the discrepancy between calculated and measured DLGs when accounting for leaf trailing. In the TG model test, ELM calculations successfully mirrored the measured leaf-edge profiles. Moreover, the median dose difference between ELM calculations and chamber doses was -0.8% in asynchronous sweeping gaps. In the VMAT dose verification, the incorporation of ELM enhanced the target dose and resulted in a gamma pass rate (2%/2 mm) exceeding 95%.</p><p><strong>Conclusion: </strong>Halcyon ELM considerably improved the accuracy of simulating actual leaf-tip transmission, both with and without leaf trailing, and it effectively accounted for the additional blocking caused by TG design. Furthermore, the introduction of ELM in Eclipse considerably enhanced the VMAT dose calculation. ELM addresses the limitations of traditional leaf models and reduces uncertainties in Halcyon dose calculations.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70044"},"PeriodicalIF":2.0,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143440965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing proton plans with three different beam delivery systems versus photon plans for head and neck tumors.","authors":"Tara Gray, Chieh-Wen Liu, Saeed Ahmed, Anna Maria Kolano, Jeremy Donaghue, Shlomo Koyfman, Neil Woody, Shauna R Campbell, Jonathan B Farr, Ping Xia","doi":"10.1002/acm2.70013","DOIUrl":"https://doi.org/10.1002/acm2.70013","url":null,"abstract":"<p><strong>Purpose: </strong>To compare plan quality among photon volumetric modulated arc therapy (VMAT) and intensity-modulated proton therapy (IMPT) with robustness using three different proton beam delivery systems with various spot size (σ) ranges: cyclotron-generated proton beams (CPBs) (σ: 2.7-7.0 mm), linear accelerator proton beams (LPBs) (σ: 2.9-5.5 mm), and linear accelerator proton mini beams (LPMBs) (σ: 0.8-3.9 mm) for the treatment of head and neck (HN) cancer with bilateral neck irradiation.</p><p><strong>Methods: </strong>Ten patients treated for oropharynx cancer with bilateral neck irradiation were planned using CPBs, LPBs, LPMBs, and VMAT. The homogeneity index (HI), mean body dose, and defined volumetric doses for selected critical organs-at-risk (OARs) were compared. Set-up uncertainties of ±3 mm and ± 3.5% range uncertainties were included in robust evaluation using V_95%Rx> 95% (Volume that covers 95% of the target volume at 95% of the prescription (Rx) dose) to high dose and low dose CTV volumes (CTV_70 Gy and CTV_56 Gy). VMAT and proton plans were compared in terms of OAR doses and mean body dose only. Homogeneity Indices were compared among IMPT plans in addition to OAR doses. The Wilcoxon signed-rank test was used to evaluate statistical differences between evaluation metrics for VMAT plans and all proton plan types.</p><p><strong>Results: </strong>OAR dose metrics were improved by 2% to 30% from CPB plans to LPB or LPMB plans. Compared to photon VMAT plans, all OAR doses except for mandible dose metrics were improved by 2% to 53% for all proton plans. The mean body dose was also improved by 7.5% from CPB to LPB and by 10.8% from CPB to LPMB. In addition, the mean body dose was also improved by 44% from VMAT to CPB, by 48% from VMAT to LPB, and by 50% from VMAT to LPMB plans. Compared to CPB plans, HI was significantly better (p < 0.05) for the LPB and LPMB plans. HI also improved considerably from VMAT to CPB, LPB, and LPMB. For both CTV_70 Gy and CTV_56 Gy, average robust evaluation across all worst-case scenarios was slightly better for CPB plans, with an average of V_95%Rx of the CTV_70 Gy of 97.6% ± 1.22%, followed by 97.2% ± 1.31% and 97.2% ± 1.35% for LPB and LPMB plans, respectively. Robustness for CTV_56 Gy showed comparable robustness across all proton plan types, with an average V_95%Rx of 97.4% ± 0.87% for CPB, 97.4% ± 1.21%, and 97.5% ± 1.08% for CPB, LPB, and LPMB plans, respectively.</p><p><strong>Conclusion: </strong>With decreased spot size, the LPB and LPMB are excellent alternatives to VMAT and CPB therapy and can significantly reduce the dose to normal tissue.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70013"},"PeriodicalIF":2.0,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143440964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of daily residual pancreatic tumor motion for deep-inspiration breath-hold radiotherapy.","authors":"Weihua Mao, Binbin Wu, Kai Ding, Sarah Han-Oh, Amol Narang","doi":"10.1002/acm2.70028","DOIUrl":"https://doi.org/10.1002/acm2.70028","url":null,"abstract":"<p><strong>Purpose: </strong>Breath-hold techniques are widely used in radiation therapy to minimize respiratory-induced tumor or organ-at-risk motion. However, residual motion persists, necessitating a reliable daily evaluation method.</p><p><strong>Methods: </strong>At our institution, fiducial markers serve as surrogates for target localization in pancreatic cancer treatment. We developed an automated method to detect fiducial markers in every projection image of cone-beam computed tomography (CBCT) scans acquired for patient setup and positioning verification. This method was retrospectively validated using data from nine pancreatic cancer patients.</p><p><strong>Results: </strong>Residual motion was observed in all patients during breath-hold maneuvers. Intrafraction target motion in repeated breath-hold simulation CT scans averaged 1.9 ± 2.2 mm, with a maximum displacement of 8 mm in the superior-inferior direction. Within a single CBCT scan, residual motion reached up to 7.3 mm, with an average drifting range of 3.8 ± 1.1 mm across 94 CBCT scans. The average standard deviation of drift was 1.5 ± 0.5 mm. Significant drift (1.3 ± 1.2 mm) and inter-breath-hold gaps (2.6 ± 2.0 mm) were detected within the same CBCT scan.</p><p><strong>Conclusion: </strong>Our method enables daily residual motion assessment without additional equipment or extra radiation exposure. This information is critical for refining planning margins in online adaptive radiation therapy, improving treatment precision and patient safety.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":" ","pages":"e70028"},"PeriodicalIF":2.0,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143441093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation oncology at crossroads: Rise of AI and managing the unexpected","authors":"Mohammad Bakhtiari","doi":"10.1002/acm2.70043","DOIUrl":"10.1002/acm2.70043","url":null,"abstract":"<p>Integrating artificial intelligence (AI) into radiation oncology has revolutionized clinical workflows, enhancing efficiency, safety, and quality. However, this transformation comes with a price of increased complexity and the emergence of unpredictable events. This letter proposes a framework based on high reliability organization (HRO) principles for managing real-time, unforeseen events. The framework emphasizes proactive risk assessment, adaptive teamwork at the situation assessment point, and reactive learning through incident analysis by placing human-centered decision-making at the core. Integrating cognitive diversity, psychological safety, and emotional intelligence fosters collective intelligence, enabling teams to navigate AI-driven complexities while safeguarding patient safety.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 3","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143440534","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}