Radiological Physics and Technology最新文献_第2页

Interfractional variability and reproducibility of accumulated dose in cervical cancer radiotherapy associated with bladder volume. 宫颈癌放疗中累积剂量与膀胱体积相关的分数间变异性和可重复性。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-10-01 DOI: 10.1007/s12194-026-01138-7

N A-Phailun, B Kadman, S Chanlaor, A Takemura, P Ditjarern, S Sookpeng

{"title":"Interfractional variability and reproducibility of accumulated dose in cervical cancer radiotherapy associated with bladder volume.","authors":"N A-Phailun, B Kadman, S Chanlaor, A Takemura, P Ditjarern, S Sookpeng","doi":"10.1007/s12194-026-01138-7","DOIUrl":"https://doi.org/10.1007/s12194-026-01138-7","url":null,"abstract":"Pelvic anatomical variations during radiotherapy for cervical cancer may alter delivered dose distributions, affecting target coverage and organ-at-risk (OAR) sparing. This study evaluated interfractional dose variability and the impact of bladder volume on accumulated dose delivery in patients treated with helical tomotherapy. A retrospective analysis of ten cervical cancer patients treated with helical tomotherapy was performed. Accumulated doses were generated using Accuray PreciseART via deformable registration of planning computed tomography (pCT) and daily MVCT images. Percentage dose deviations between planned and accumulated doses were analyzed using paired t-tests, while differences among three bladder volume groups were evaluated using linear mixed-effects models. Accumulated PTV doses were significantly lower than planned, with the greatest reduction in D95 (-3.36%, p < 0.001). Among OARs, the bowel showed the largest reduction, particularly D195cc (-5.18%, p < 0.001). Medium and large bladder volumes were associated with greater reductions in bowel D195cc and Dmean than small volumes, with no clear difference between the medium and large groups. Increasing bladder volume also showed a non-significant trend toward greater PTV dose reduction, while bowel dose deviations gradually decreased during treatment. Interfractional anatomical variation caused measurable deviations in accumulated dose, particularly for PTV D95 and bowel D195cc. Although medium and large bladder volumes were associated with slightly greater bowel dose reductions than small volumes, the between-group differences were modest, with no significant difference between the medium and large groups. These findings support individualized and reproducible bladder preparation.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149116346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of deformable image registration algorithms for planning CT and CBCT in prostate cancer patients treated with external beam radiation therapy. 外束放射治疗前列腺癌患者计划CT与CBCT的形变图像配准算法比较。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-29 DOI: 10.1007/s12194-026-01143-w

Hussam H Jassim, Nooshin Banaee, Hassan Ali Nedaei, Toshikazu Imae

{"title":"Comparison of deformable image registration algorithms for planning CT and CBCT in prostate cancer patients treated with external beam radiation therapy.","authors":"Hussam H Jassim, Nooshin Banaee, Hassan Ali Nedaei, Toshikazu Imae","doi":"10.1007/s12194-026-01143-w","DOIUrl":"https://doi.org/10.1007/s12194-026-01143-w","url":null,"abstract":"This study evaluated the performance of three categories of deformable image registration (DIR), namely intensity-based, spline-based, and hybrid methods, for planning CT (pCT)-to-cone-beam CT (CBCT) registration to evaluate the accuracy of different DIR approaches for pCT-to-CBCT registration and assess their potential applicability to CBCT-based adaptive radiotherapy. Fourteen default registration methods were compared with the Anatomically Constrained Deformation Algorithm (ANACONDA) using a CIRS phantom and five prostate cancer patients. Registration accuracy was assessed using Target Registration Error (TRE), Dice Similarity Coefficient (DSC), and image quality metrics. Deformed CT (dCT) consistently outperformed CBCT, demonstrating substantial improvements in image quality across Phantom and patient studies. ANACONDA achieved the highest registration accuracy, with TRE < 0.2 cm for prostate landmarks and DSC > 0.90 for target volumes and organs-at-risk. ANACONDA outperformed intensity-based and spline-based registration methods, providing improved image quality and anatomical registration accuracy, thereby facilitating more accurate image guidance for adaptive radiation in pelvic radiotherapy.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149082071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transition from a detector-dose-based to a CNR-based cerebral angiography system: evaluation of image quality and radiation dose. 从基于探测器剂量到基于核磁共振的脑血管造影系统的转变：图像质量和辐射剂量的评估。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-29 DOI: 10.1007/s12194-026-01141-y

Kota Hachiya, Hiroki Abiko, Koichi Chida, Yoshikazu Matsuda

{"title":"Transition from a detector-dose-based to a CNR-based cerebral angiography system: evaluation of image quality and radiation dose.","authors":"Kota Hachiya, Hiroki Abiko, Koichi Chida, Yoshikazu Matsuda","doi":"10.1007/s12194-026-01141-y","DOIUrl":"https://doi.org/10.1007/s12194-026-01141-y","url":null,"abstract":"To evaluate the image quality and clinical radiation dose of a cerebral angiography system featuring contrast-to-noise ratio (CNR)-based exposure control for neurovascular endovascular treatment (EVT). Image quality was evaluated using a quality control phantom under fluoroscopy and digital subtraction angiography (DSA). Clinical radiation dose was retrospectively compared between a conventional angiography system using detector dose-based exposure control (61 cerebral aneurysm EVT procedures) and a new angiography system using CNR-based exposure control (99 procedures). Patient entrance reference air kerma (Ka,r) and air kerma-area product (PKA) were analyzed. The new system demonstrated significantly higher observer scores than the conventional system for both fluoroscopy and DSA, including spatial resolution, low-contrast resolution, and dynamic range. The median total Ka,r was 1818 [1301-2744] mGy with the new system and 2283 [1580-3184] mGy with the conventional system, representing a 20% reduction (p < 0.05). Conversely, the median total PKA increased by 26% (173 [120-237] vs. 137 [93-207] Gy·cm2, p < 0.05), but remained below the current Japanese diagnostic reference level for cerebral aneurysm EVT. Compared with the conventional system, the new angiography platform demonstrated superior image quality under phantom conditions and was associated with a 20% reduction in total Ka,r during cerebral aneurysm EVT. Although the total PKA increased by 26%, this increase may have reflected differences in the magnification strategy between the two systems, suggesting a need for further optimization.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149082184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Toward optimal radiotherapy in tongue cancer: a comparative study of IMRT and VMAT. 舌癌最佳放疗：IMRT与VMAT的比较研究。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-28 DOI: 10.1007/s12194-026-01145-8

Ramita Sharma, Anuj Kumar, Satvir Singh, Neeraj Jain, Meena Sudan

{"title":"Toward optimal radiotherapy in tongue cancer: a comparative study of IMRT and VMAT.","authors":"Ramita Sharma, Anuj Kumar, Satvir Singh, Neeraj Jain, Meena Sudan","doi":"10.1007/s12194-026-01145-8","DOIUrl":"https://doi.org/10.1007/s12194-026-01145-8","url":null,"abstract":"This retrospective study compared the dosimetric performance of intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) in patients with T3N2 stage squamous cell carcinoma of the tongue treated in a post-operative setting. Thirty patients received 60 Gy in 30 fractions. IMRT plans were developed and corresponding VMAT plans were generated in the Monaco treatment planning system with identical target coverage and organ-at-risk (OAR) constraints using the Monte Carlo algorithm (3 mm grid, 2% statistical uncertainty). Dose-volume parameters for the planning target volume (PTV) and plan quality indices including conformity index (CI), homogeneity index (HI), and uniformity index (UI) were evaluated alongside OAR doses. Both IMRT and VMAT achieved clinically acceptable and comparable target coverage. The small numerical differences observed in PTV dosimetric parameters and plan quality indices between the two techniques should be interpreted with caution, as they fall within the range of the 2% Monte Carlo statistical uncertainty used in dose calculation. OAR doses were broadly similar between techniques, with IMRT demonstrating marginally lower doses to certain serial structures including the spinal cord and brainstem, though all values remained well within established tolerance limits for both techniques. The primary clinically meaningful advantage of VMAT was improved delivery efficiency, demonstrated by reduced monitor units (1033.9 vs. 1212.89) and shorter treatment time (approximately 5 min vs. 8 min). For T3N2 post-operative tongue carcinoma, both IMRT and VMAT provide clinically equivalent dosimetric plan quality, with VMAT offering a significant advantage in treatment delivery efficiency.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149076312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accuracy and feasibility of sitting bladder volume measurement using portable ultrasound device in prostate radiotherapy. 便携式超声仪在前列腺放射治疗中坐式膀胱体积测量的准确性和可行性。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-28 DOI: 10.1007/s12194-026-01140-z

Yosuke Miyasaka, Masahide Saito, Hikaru Nemoto, Ryota Tozuka, Koji Ueda, Yoshihito Aikawa, Hiroaki Ikegawa, Hiroshi Onishi

{"title":"Accuracy and feasibility of sitting bladder volume measurement using portable ultrasound device in prostate radiotherapy.","authors":"Yosuke Miyasaka, Masahide Saito, Hikaru Nemoto, Ryota Tozuka, Koji Ueda, Yoshihito Aikawa, Hiroaki Ikegawa, Hiroshi Onishi","doi":"10.1007/s12194-026-01140-z","DOIUrl":"https://doi.org/10.1007/s12194-026-01140-z","url":null,"abstract":"This study evaluated the feasibility and accuracy of bladder volume measurement in the sitting position during prostate radiotherapy using a portable ultrasound device, compared with the conventional supine position. Forty patients (mean age 73.1 years; range 59-85) undergoing prostate radiotherapy were prospectively enrolled. Following planning CT (pCT), bladder volumes were measured using ultrasound in the supine position and immediately thereafter in the sitting position to minimize temporal variation. Reference bladder volumes were contoured on pCT images. Measurement error rates, correlations, and agreement (Bland-Altman, Wilcoxon signed-rank test) were evaluated. A predefined ± 15% margin, based on device specifications and clinical standards, defined clinically acceptable accuracy. Evaluated bladder volumes ranged from 99 to 435 mL. Mean differences between ultrasound and pCT volumes were - 25.9 ± 37.2 mL (supine) and - 12.2 ± 32.5 mL (sitting), corresponding to error rates of 14.1% and 9.1%, respectively. Strong correlations with pCT were observed in both positions (r = 0.89-0.92). Although a statistically significant difference was detected between positions (p < 0.01), the mean difference (supine minus sitting) was - 13.7 mL. The mean absolute difference between the two positions was 27.6 mL (median: 23 mL; range: 1-139 mL), and Bland-Altman analysis demonstrated agreement within the predefined margin. Bladder volume measurement in the sitting position demonstrated clinically acceptable accuracy for initial volume estimation. While not a perfect substitute for supine measurement due to individual variability, it serves as a practical tool for workflow optimization, such as pretreatment screening.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149076304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hybrid geometric and evolutionary optimization framework for radiosurgery planning: isocenter selection and angle optimization for multiple brain metastases. 放射手术计划的几何和进化混合优化框架：多发性脑转移的等中心选择和角度优化。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-23 DOI: 10.1007/s12194-026-01139-6

Quang Vinh Pham, Quang Trung Pham

{"title":"Hybrid geometric and evolutionary optimization framework for radiosurgery planning: isocenter selection and angle optimization for multiple brain metastases.","authors":"Quang Vinh Pham, Quang Trung Pham","doi":"10.1007/s12194-026-01139-6","DOIUrl":"https://doi.org/10.1007/s12194-026-01139-6","url":null,"abstract":"This study aims to develop and evaluate the performance of Collimator Angles Optimization Software version 2 (CAOS-v2) for stereotactic radiosurgery (SRS) planning in patients with multiple brain metastases. Treatment planning was performed in Eclipse v13.6 with RapidArc on the TrueBeam STx. The primary objective is to reduce the volume of normal brain tissue receiving 12 Gy (V12Gy) while maintaining overall plan quality. CAOS-v2 determines the isocenter location using the Smoothed Weiszfeld Algorithm to compute the geometric median of the target centers, in contrast to traditional centroid-based placement. The software subsequently employs a genetic algorithm to optimize couch-collimator angle pairs, reducing the impact of the island blocking problem. Twenty-six clinical cases were retrospectively replanned using CAOS-v2 with a single-fraction prescription dose of 18 Gy applied to all treatment plans. Plans were evaluated using Conformity Index (CI), Gradient Index (GI), Gradient Measure (GM), organs at risk (OARs), and the V12Gy of healthy brain tissue. Application of CAOS-v2 resulted in a reduction of V12Gy by 17.6-38.1% compared to the conventional planning approach. The CI remained stable, indicating consistent dose uniformity across treatment plans. No increase in dose to OARs was observed. Additionally, both the GI and GM significantly decreased, indicating improved dose fall-off characteristics attributable to CAOS-v2. Integration of CAOS-v2 into the planning workflow significantly reduces normal brain dose in multi-metastatic SRS without compromising conformity or gradient performance, supporting its clinical applicability for automated treatment parameter optimization.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149031607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of the image quality index with MRI motion artifacts on tumor segmentation using deep learning. 基于MRI运动伪影的深度学习肿瘤分割图像质量指标评价。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-22 DOI: 10.1007/s12194-026-01144-9

Masafumi Akanuma, Keisuke Usui, Ryoma Tsuchiya, Eiichi Maehara, Keisuke Fujita, Tatsuya Choji, Daiki Sakakibara, Hajime Sakamoto, Shinsuke Kyogoku, Hiroyuki Daida

{"title":"Evaluation of the image quality index with MRI motion artifacts on tumor segmentation using deep learning.","authors":"Masafumi Akanuma, Keisuke Usui, Ryoma Tsuchiya, Eiichi Maehara, Keisuke Fujita, Tatsuya Choji, Daiki Sakakibara, Hajime Sakamoto, Shinsuke Kyogoku, Hiroyuki Daida","doi":"10.1007/s12194-026-01144-9","DOIUrl":"https://doi.org/10.1007/s12194-026-01144-9","url":null,"abstract":"Motion artifacts substantially degrade magnetic resonance imaging (MRI) quality and can reduce diagnostic accuracy. Although deep learning-based segmentation has achieved high performance, the degree of motion-related degradation that begins to impair tumor contour delineation and the corresponding image quality criteria remains unclear. This study investigated the relationship between image quality and the agreement of segmentation outputs obtained from original and motion-degraded MRI images in deep learning-based brain tumor segmentation and explored tentative reference values for image quality metrics. Tumor contours were manually delineated on fluid-attenuated inversion recovery images from patients with glioma, and a segmentation model was tested. Motion artifact images were then generated through simulation, and the relationship between the generated tumor contours and image quality was analyzed. The tumor contours were evaluated using the Dice similarity coefficient (DSC), while image quality was assessed using mean absolute error (MAE), root mean squared error (RMSE), structural similarity index measure (SSIM), and peak signal-to-noise ratio (PSNR). No strong correlations were observed between DSC and the evaluated image quality metrics. However, SSIM showed a positive association with visual assessment, suggesting that it better reflects tumor boundary visibility and perceived image degradation than other indices. In particular, an SSIM of 0.8 corresponded to a visual assessment score of 2 or higher, indicating a quality level at which observers can visually distinguish tumor boundaries. Because these findings may depend on the number of cases and the segmentation model used, further validation with clinical images is required to establish practical image quality criteria.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149026340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantifying three-dimensional displacement of cardiac implantable electronic devices and implications for safety margins in radiotherapy. 心脏植入式电子装置三维位移的量化及其放射治疗安全裕度的意义。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-21 DOI: 10.1007/s12194-026-01142-x

Takahiro Kubota, Ryota Onizuka, Kazuki Kajiwara, Tatsunori Saho, Koichiro Muraki

{"title":"Quantifying three-dimensional displacement of cardiac implantable electronic devices and implications for safety margins in radiotherapy.","authors":"Takahiro Kubota, Ryota Onizuka, Kazuki Kajiwara, Tatsunori Saho, Koichiro Muraki","doi":"10.1007/s12194-026-01142-x","DOIUrl":"https://doi.org/10.1007/s12194-026-01142-x","url":null,"abstract":"This study aimed to quantitatively evaluate the three-dimensional (3D) displacement of cardiac implantable electronic devices (CIEDs) during radiotherapy and derive safety margins. Sixteen treatment courses (13 patients, 262 fractions) were retrospectively analyzed. Daily device displacement was quantified using orthogonal 2D kV images relative to clinical bone-matching. To evaluate manual registration uncertainty, the intraclass correlation coefficient and minimal detectable change (MDC) were calculated. To assess the impact of patient positioning, displacements were compared between arm-up and arm-down groups. Planning organ at risk volume (PRV) margins were derived from systematic and random errors. A maximum 3D displacement of 24 mm was observed. Manual registration demonstrated good to excellent reproducibility for the primary translational axes. The maximum MDC was 3.6 mm for the 3D displacement vector. While overall displacement distributions showed no significant differences between arm positions, extreme medial displacement significantly increased in the arm-up group (p < 0.05). The calculated PRV margins reached a maximum of 7.3 mm in the longitudinal direction for the arm-up group. Throughout the radiotherapy course, CIEDs can undergo displacement independently of the skeletal structure. The PRV margins derived here provide a quantitative basis for pre-treatment dose evaluation. The observed range of displacement can inform treatment planning and supports verification of the device position at each fraction via image-guided radiotherapy.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149018167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Consensus approach to shape regularization in cross-modality cardiac segmentation. 跨模态心脏分割中形状正则化的共识方法。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-15 DOI: 10.1007/s12194-026-01121-2

Hirohisa Oda, Toshiaki Akita

{"title":"Consensus approach to shape regularization in cross-modality cardiac segmentation.","authors":"Hirohisa Oda, Toshiaki Akita","doi":"10.1007/s12194-026-01121-2","DOIUrl":"https://doi.org/10.1007/s12194-026-01121-2","url":null,"abstract":"Adapting segmentation models to new imaging modalities without original training data is known as source-free domain adaptation (SFDA). SFDA is often unstable and limited to two-dimensional slices, causing inconsistencies and errors between adjacent slices. This problem is apparent in cardiac segmentation when adapting from computed tomography (CT) to magnetic resonance imaging (MRI), as these inconsistencies lead to three-dimensional anatomical distortions. In this study, we analyzed a postprocessing framework for SFDA-based cardiac segmentation using a probabilistic consensus map (PCMap). Inspired by traditional probabilistic atlases, PCMap is an average anatomical map generated from all initial segmentations, intended to enforce structural consistency. This framework was evaluated on CT and MRI volumes from the publicly available multi-modality whole-heart segmentation dataset. PCMap-guided refinement increased shape regularity and reduced interslice discontinuities but did not consistently improve voxel-wise accuracy. A correlation of 0.803 between reference quality and refinement performance was found, showing that the choice of reference volume strongly affects refinement performance.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148976796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Game engine-driven high-precision collision simulation system for radiation therapy: development and clinical evaluation. 游戏引擎驱动的高精度放射治疗碰撞模拟系统：开发与临床评价。

IF 1.6

Radiological Physics and Technology Pub Date : 2026-09-15 DOI: 10.1007/s12194-026-01135-w

Yuri Toyohara

{"title":"Game engine-driven high-precision collision simulation system for radiation therapy: development and clinical evaluation.","authors":"Yuri Toyohara","doi":"10.1007/s12194-026-01135-w","DOIUrl":"https://doi.org/10.1007/s12194-026-01135-w","url":null,"abstract":"Pre-treatment verification is essential to prevent physical collisions between the gantry and the patient during radiation therapy. Conventionally, physical \"dry runs\" have been performed to ensure safety; however, these procedures can create bottlenecks in clinical workflows. This study aimed to develop virtual collision simulation software using a freely available development environment and to evaluate its performance through phantom studies and verification of clinical treatment plans. High-fidelity three-dimensional (3D) models of the linear accelerator and various immobilization devices were constructed. The software was developed in the Unity environment and incorporated a collision detection system and a function to predict treatment couch coordinates. Collision detection accuracy was assessed using phantom experiments by comparing simulated results with those obtained from the actual linear accelerator. The accuracy of couch coordinate predictions and collision detection performance were retrospectively evaluated using clinical data from 71 treatment plans. All collision prediction errors in the phantom experiments fell conservatively within a 3.00° margin prior to physical contact, and couch coordinate predictions were within 1 cm of the actual values. In the evaluation of clinical plans, the software achieved a true-positive rate of 100% and a negative predictive value of 100%. The developed software achieved high-precision collision detection despite being created in a free platform, thereby ensuring both high performance and broad reproducibility. By serving as an effective pre-screening tool and reducing the need for physical dry runs, this cost-effective and accessible solution streamlines workflow and enhances patient safety.","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148977353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0