Journal of Applied Clinical Medical Physics最新文献

{"title":"Optimizing cardio-respiratory motion management in stereotactic arrhythmia radioablation through mid-position planning target volume","authors":"Adèle Gabillaud,&nbsp;Louis Rigal,&nbsp;Raphaël Martins,&nbsp;Renaud De Crevoisier,&nbsp;Juan Cisneros,&nbsp;Loïg Duvergé,&nbsp;Mathieu Lederlin,&nbsp;Nolwenn Delaby,&nbsp;Karim Benali,&nbsp;Antoine Simon,&nbsp;Julien Bellec","doi":"10.1002/acm2.70170","DOIUrl":"https://doi.org/10.1002/acm2.70170","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose/objective</h3>\u0000 \u0000 <p>This study proposes an implementation of the mid-position (MidP) approach to compensate for cardio-respiratory motions in the context of Stereotactic Arrhythmia Radioablation (STAR) and evaluates its benefits compared to an internal target volume (ITV) approach.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Materials and methods</h3>\u0000 \u0000 <p>Fifteen patients who underwent STAR for refractory ventricular tachycardia in our institution were included in this retrospective planning study. For each patient, a cardiac-gated four-dimensional computed tomography (4D-CT_card) scan and a respiratory-gated four-dimensional computed tomography (4D-CT_resp) were acquired. All patients were treated using a volumetric modulated arc therapy technique using an in-treatment Cone-Beam CT (CBCT) image guidance. The MidP approach was implemented to compensate for uncertainties, including cardio-respiratory motions characterized using the 4D-CT_card and 4D-CT_resp scans, and the inter-fraction motions measured using the CBCT scans. For comparison purposes, the ITV approach was also implemented. Both approaches were compared in terms of planning target volume (PTV) volumes, doses to organs-at-risk, and clinical target volume (CTV) doses, assessed using a 4D modeling method that estimates the accumulated dose.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Compared with the ITV method, the MidP approach resulted in a mean [min-max] relative PTV volume reduction of 30% [19%, 48%] (<i>p</i> &lt; 0.001, Wilcoxon signed rank test). The mean [min-max] D95% CTV coverage was 105% [101%–114%] and 107% [101%–117%] of the prescription dose for MidP and ITV-based plans, respectively. The median dose to the whole heart was significantly lower with MidP-based plans with a mean difference of −0.5 Gy (<i>p</i> = 0.0084). The near-maximum dose (D1%) delivered to left coronary arteries, aorta, and stomach was systematically lower with the MidP-based plans.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Compared to ITV based approach, the use of MidP strategy for treatment planning of STAR leads to significantly smaller PTV and lower surrounding OAR doses while still achieving a clinically acceptable CTV coverage.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70170","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615113","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":"Analysis of the institutional free market in accredited medical physics graduate programs","authors":"Brian W. Pogue,&nbsp;Alexander P. Niver","doi":"10.1002/acm2.70164","DOIUrl":"https://doi.org/10.1002/acm2.70164","url":null,"abstract":"<p>Medical Physics education is largely delivered through accredited programs where admission numbers and funding for students are controlled by the individual institutions providing the educational programs. Public data from these accredited graduate programs, along with funding data, can be used to analyze institutionally driven trends in the market for providing this education. Temporal trends from 2017 to 2023 show robust growth in MS graduates, increasing at an average of 17.7 per year, as compared to steady but modest growth in PhDs, increasing by 3.6 per year. The current ratio is 2:1 in MS:PhD for total annual graduates in North America. Trends in funding show self-funding of MS students is a dominant pathway in domestic programs, with this being less dominant in international programs. Those programs dominated by accredited MS education have their largest fraction of faculty in radiation oncology departments, whereas those dominated by PhD education have their largest fraction of faculty in radiology departments. Overall, NIH funding in the space of radiation diagnostics and therapeutics has been largely static over this timeframe, but with a notable recent rise in NCI funding in the last 5 years. This can be contrasted to a substantial 5X–6X rise in NIH funding for engineering research programs during this same period, with significant increases in trainee funding there. Taken as a whole, this survey shows that growth in the field of medical physics education is dominated by MS graduates, presumably servicing the expanded growth needs for well-trained clinical physicists. However, the research infrastructure that supports PhD training in medical physics seems likely to be growing modestly and has missed the growth trend of NIH funding to non-accredited programs such as biomedical engineering.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70164","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615109","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":"Enhancing inguinal tumor treatment outcomes with a customized 3D-printed bolus","authors":"Xing Li,&nbsp;Stephen Bhagroo,&nbsp;Fan-Chi Su,&nbsp;Robabeh Rahimi,&nbsp;Jonathan Tward","doi":"10.1002/acm2.70175","DOIUrl":"https://doi.org/10.1002/acm2.70175","url":null,"abstract":"<p>Traditional boluses for pelvic lesions present challenges, including compromised skin dose coverage from large air gaps in treatment plans and increased uncertainties in treatment delivery due to variations in bolus fitting. This study evaluates the clinical benefits of a patient-specific, 3D-printed bolus (pBolus) in external beam radiation therapy (EBRT) for extramammary Paget's disease in the inguinal fold. A three-dimensional (3D) conformal plan utilizing the pBolus was compared to a conventional Superflab bolus (sBolus) under identical beam arrangements. The pBolus improved dose conformity by reducing air gaps in the treatment plan, and therefore, it was selected for clinical treatment. Weekly setup imaging revealed air gaps predominantly along the inguinal fold, demonstrating overall consistency in bolus fitting with minor air gap variations. Additionally, in vivo dosimetry confirmed dose accuracy. As a result, the patient achieved a favorable outcome, with no clinical evidence of disease at the follow-up visit.</p>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70175","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615170","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":"Development of a hybrid automated chart checking, data collection, and analysis system","authors":"Edward L. Clouser Jr.,&nbsp;Quan Chen,&nbsp;Daniel P. Harrington,&nbsp;Yi Rong,&nbsp;Courtney R. Buckey","doi":"10.1002/acm2.70161","DOIUrl":"https://doi.org/10.1002/acm2.70161","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To describe the creation and clinical deployment of an integrated stand-alone hybrid automated chart review platform that is comprised of a database, oncology information system (OIS) interfaces, and a user interface (UI).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A consensus checklist was developed to homogenize the practices of clinical physics staff and physics residents for all plan types. Critical review of the single checklist's items led to the creation of a new concept, the “plan attribute,” which permits specialization of the final checklist based on the characteristics of a particular plan. Only relevant and applicable tests are automatically populated to form a plan checklist based on plan attributes. Each populated checklist in this hybrid automation platform includes elements of full automation, steps or functions that use automation to augment a human input or effort, as well as steps completed by humans. Logging and categorizing of deficiencies found during the chart check was also implemented.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Chart check data was analyzed for an over 4-year time span starting from the clinical deployment of the tool in October 2020. This analysis included a total of 427 073 tests spread among 7882 initial chart checks. The recorded deficiencies at three triage levels showed 7116 minor errors, 679 major errors, and 71 plan rejections. The plan rejection level is the highest chart deficiency, which required the plan to be rejected and sent back for serious remediation and/or new plan generation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>This report describes the successful development and implementation of a hybrid-automated chart checking program. The software leverages modern database and software design to improve the per case performance and experience of a multi-user group. Chart check database permits high-level review and improvement in all aspects of plan check and user performance.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70161","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615297","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":"Analysis of treatment planning time and optimization parameters for inverse planning for intracavitary and interstitial brachytherapy in uterine cervical cancer","authors":"Jun Tomihara,&nbsp;Jun Takatsu,&nbsp;Naoya Murakami,&nbsp;Noriyuki Okonogi,&nbsp;Tatsuya Inoue,&nbsp;Kotaro Iijima,&nbsp;Kotaro Matsuda,&nbsp;Naoto Shikama","doi":"10.1002/acm2.70157","DOIUrl":"https://doi.org/10.1002/acm2.70157","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>This study aimed to investigate the effect of inverse planning parameters on dose-volume indices in brachytherapy for uterine cervical cancer.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Fourteen consecutive patients with cervical cancer who received intracavitary and interstitial brachytherapy (IC/ISBT) were selected. Tandem, ovoid, and interstitial needles were used in all cases. The evaluation plans were recalculated from the first fraction of clinical brachytherapy plans. The correlation between the 11 dose optimization parameters of inverse planning and the 13 dose-volume indices was evaluated. The parameters were adjusted in five levels, and dose optimization was performed in hybrid inverse planning optimization (HIPO). Spearman's rank correlation and multiple regression analyses were conducted to assess the association between the parameters and the indices. The indices included clinical target volume (CTV) dose, organ-at-risk (OAR) dose, homogeneity, and conformity. Additionally, the correlation between optimization parameters and calculation time was investigated, along with a technique for efficiently generating treatment plans.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>“CTV Max Weight” and “OAR Max Weight” were the key parameters significantly affecting the indices. Increasing “CTV Max Weight” improved homogeneity but reduced the target coverage. The effect of “OAR Max Weight” on the dose reduction of CTV_HR D₉₀ (β = −0.59) was more significant than that on the dose reduction of OAR D_2cc (β = −0.21). In addition, adjusting “CTV Min Weight” and “CTV Volume” could reduce the hyper-dose sleeve without increasing the OAR dose. A large number of normal tissue sampling points could negatively affect the dose distributions and increase the calculation times.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>“CTV Max Weight” and “OAR Max Weight” were the most influential parameters in HIPO, significantly affecting dose-volume indices in IC/ISBT for uterine cervical cancer. Additionally, parameters that regulate the hyper-dose sleeve and needle-delivered dose were identified. The quality of treatment planning can be maintained and planning time reduced by appropriately optimizing these parameters.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70157","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615302","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":"Implementing team science in undergraduate medical physics research","authors":"Ashley J. Cetnar","doi":"10.1002/acm2.70169","DOIUrl":"https://doi.org/10.1002/acm2.70169","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>Many undergraduate students are eager to learn more about potential career opportunities. While physics majors are often aware of research opportunities within their home department, students may not be aware of how physics can be applied in medicine. An alternate framework for a 10-week summer undergraduate research experience using a collaborative Team Science approach is presented.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>The Team Science program is described, with feasibility shared based on the experiences of four students who piloted the program. Students explored four different projects throughout the summer as part of the 10-week program and assumed different team roles for each project fostering experience understanding team dynamics. Changes in student attitudes toward science research were quantified using validated surveys and qualitative responses are also summarized.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Average self-reported student scores in the Attitudes and Approaches to Problem Solving Survey increased 9.8% and Colorado Learning Attitudes about Science Survey for Experimental Physics increased 14.2% after the summer research experience. Areas with the highest reported gains from the program from the Undergraduate Research Student Self-Assessment Survey included understanding what everyday research work is like, engaging in real-world science research, and preparation for the future.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Using a Team Science approach allowed for students to explore multiple research questions during the summer and experience a more authentic and integrated approach to how research is conducted. This model can be expanded and adapted for students to identify medical physics as a career for applying their physics knowledge to solve problems that will advance human health earlier in their career.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70169","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615032","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":"Pelvic dose accumulation accuracy in a CBCT based online adaptive radiotherapy system","authors":"Mikel Byrne,&nbsp;Xenia Ray,&nbsp;Kelly Kisling,&nbsp;Ben Archibald-Heeren,&nbsp;Robert Finnegan,&nbsp;Suhuai Luo,&nbsp;Trent Aland,&nbsp;Peter Greer","doi":"10.1002/acm2.70160","DOIUrl":"https://doi.org/10.1002/acm2.70160","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Introduction</h3>\u0000 \u0000 <p>Accurate dose accumulation is essential for understanding the delivered dose in online adaptive radiotherapy (OART). The aim of this study is to quantify the dose accumulation accuracy and clinical significance of dose accumulation errors in pelvis treatments using the Ethos v1.1 and v2.0 systems.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Method</h3>\u0000 \u0000 <p>Three pelvic CTs had anatomically realistic deformation vector fields (DVF) applied to create new modified images. These modified images were then used as treatment images in simulated OART treatment sessions, and the dose was accumulated by the Ethos system (<i>D(fx)_Ethos</i>). The inverse of the applied (true) DVF was also used to accumulate the delivered dose (<i>D(fx)_True</i>). The maximum applied DVF magnitude was compared to the maximum DVF magnitude calculated by the Ethos v1.1 and v2.0 systems. A 3D gamma analysis was performed between <i>D(fx)_Ethos</i> and <i>D(fx)_True</i>, and the clinical goals for each scenario were compared.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Large discrepancies in deformable registration magnitude were noted between the applied DVF and the Ethos DVF from both Ethos versions. All Ethos v1.1 results had 90% of points passing a 3%/2 mm gamma analysis, whilst Ethos v2.0 results did not reach this benchmark in all of the simulated scenarios. Results were particularly poor for the v2.0 prostate case. Inaccuracies in the dose accumulation process caused 6% of goals to change sufficiently such that the goal was reported as met or exceeded when it was not.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The Ethos v1.1 dose accumulation system has been found to perform acceptably for the pelvic CTs tested in this study. For the Ethos v2.0 system substantial discrepancies in the dose accumulation were noted.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70160","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615190","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":"Utilization of spectral filteration for ultra-low dose brain CT in pediatric patients for diagnosis of craniosynostosis: A phantom study","authors":"Connor Braniff,&nbsp;Michael Ditchfield,&nbsp;Manuel Gubser,&nbsp;Ahilan Kuganesan,&nbsp;M. K. Badawy","doi":"10.1002/acm2.70176","DOIUrl":"https://doi.org/10.1002/acm2.70176","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objectives</h3>\u0000 \u0000 <p>This study evaluates the effectiveness of spectral filtration—specifically Tin and SilverBeam filters—in achieving ultra-low radiation doses in pediatric computed tomography (CT) imaging for craniosynostosis diagnosis. We investigate whether these filters can reduce radiation to levels comparable to or below those of standard four-view skull x-rays, while maintaining diagnostic accuracy. Unlike previous research focused broadly on dose reduction, this study highlights the potential of Tin and SilverBeam filtration as a promising solution.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>CT images were acquired using a pediatric head fracture phantom, with sutures simulating craniosynostosis, on two scanners with different spectral filters. The CTDIvol was reduced by varying percentages from standard pediatric protocols using Tin and SilverBeam filters. Image quality and radiation dose were quantitatively assessed, while two radiologists performed qualitative evaluations.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Dose comparisons showed that images with at least a 89.2% reduction in CTDIvol using the Tin filter and a 91.4% reduction when using the SilverBeam filter resulted in lower doses than a standard four-view skull x-ray (0.09 mSv). The greatest dose reduction (up to 161%) occurred with SilverBeam at a 99.9% reduction in CTDIvol. While significant pixel intensity changes were observed at the sutures, spatial resolution decreased at lower dose settings. Two pediatric radiologists observed clear skull and orbit outlines under clinical conditions, but coronal sutures became undetectable near 90% CTDIvol reduction.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Spectral filtration ultra-low-dose CT significantly reduces radiation exposure compared to four-view skull x-rays, showing promise for diagnosing craniosynostosis. Further patient-based studies are needed to validate diagnostic efficacy.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Advances in knowledge</h3>\u0000 \u0000 <p>This study is the first to assess spectral filtration in ultra-low-dose pediatric head CT, highlighting significant dose reductions without compromising diagnostic quality, and stressing the need for further validation.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70176","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615033","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":"Differentiating mega cisterna magna from cisterna magna arachnoid cysts: The diagnostic utility of quantitative diffusion-weighted imaging parameters","authors":"Quanxiang Li,&nbsp;Zhe Feng,&nbsp;Haichao Cheng,&nbsp;Xin Cao,&nbsp;Yaping Ge,&nbsp;Hao Shi,&nbsp;Jun-Ying Wang","doi":"10.1002/acm2.70166","DOIUrl":"https://doi.org/10.1002/acm2.70166","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>To explore the utility of diffusion-weighted imaging (DWI)-derived apparent diffusion coefficient (ADC) and exponential apparent diffusion coefficient (eADC) parameters in differentiating mega cisterna magna (MCM) from cisterna magna arachnoid cysts (CMAC).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Retrospective analysis of MRI data from 40 MCM patients, 46 CMAC patients (confirmed via clinical follow-up and imaging criteria), and 36 temporal arachnoid cysts (TAC) as controls was performed. Independent sample <i>t</i>-tests were used to compare ADC and eADC values among the three groups.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The eADC values of MCM, CMAC, and TAC were (3.75 ± 0.27) × 10⁻², (4.53 ± 0.54)×10⁻², and (4.35 ± 0.30) ×10⁻² mm²/s, respectively. There was no significant difference in the eADC value between CMAC and TAC (<i>p</i> = 0.191). However, the eADC value of MCM was significantly different from the two groups (<i>p</i> = 0.000). The ADC values of MCM, CMAC, and TAC were (3.30 ± 0.08) × 10⁻³, (3.11 ± 0.12) ×10⁻³, and (2.97 ± 0.71) × 10⁻³mm²/s, respectively. Significant differences in ADC were observed between MCM and both CMAC and TAC (<i>p</i> = 0.000/0.003).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>DWI-derived ADC and eADC parameters can effectively differentiate mega cisterna magna from cisterna magna arachnoid cysts.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70166","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615114","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":"A novel protocol for parametrization of a beam model for small stereotactic beams","authors":"Tim Melhus,&nbsp;Mohammed Ghazal,&nbsp;Hamza Benmakhlouf","doi":"10.1002/acm2.70158","DOIUrl":"https://doi.org/10.1002/acm2.70158","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Introduction</h3>\u0000 \u0000 <p>Most Treatment Planning Systems (TPS) utilize parameterized multi-source models to represent the radiation beam of linacs. However, small stereotactic beams require special attention due to the importance of correct spot- and field-size definition. The purpose of this work is to develop a protocol for configuring a beam model that provides accurate representation of stereotactic beams.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Material and methods</h3>\u0000 \u0000 <p>6 MV flattening filter free (FFF) dose-profiles were measured for Millennium multileaf collimator (MLC)-collimated field sizes (2 × 2 cm²–5 × 5 cm²). They served as a reference against which corresponding TPS-profiles were optimized by configuring the Dosimetric Leaf Gap (DLG) and the Effective Spot Size (ESS). The optimized model was evaluated by comparing calculated and measured stereotactic radiotherapy (SRT)-plans. The proposed protocol was implemented on Anisotropic Analytical Algorithm (AAA) and Acuros XB in the Eclipse TPS.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Improvement in the agreement between measured and modelled profiles are identified using the suggested protocol. The DLG was determined at an optimum of 0.9 mm for both models whereas the ESS was determined to be (0.5, 0) mm and (1, 0,5) mm for AAA and Acuros XB, respectively. Compared to the standardly configured clinical model, the optimized AAA (Acuros XB) model showed an average improvement in gamma pass-rates of 2% (3%) with film measurements.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The standard protocol for TPS commissioning was shown to produce a sub-optimal beam model for small treatment volumes. The proposed protocol in this work results in a better modelling of small stereotactic beams.</p>\u0000 </section>\u0000 </div>","PeriodicalId":14989,"journal":{"name":"Journal of Applied Clinical Medical Physics","volume":"26 7","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/acm2.70158","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144615189","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}