Journal of Applied Clinical Medical Physics

Beyond a constant proton relative biological effectiveness: A survey of clinical and research perspectives among proton institutions in Europe and the United States
Ödén J, Eriksson K, Kaushik S and Traneus E
Although proton relative biological effectiveness (RBE) depends on factors like linear energy transfer (LET), tissue properties, dose, and biological endpoint, a constant RBE of 1.1 is recommended in clinical practice. This study surveys proton institutions to explore activities using functionalities beyond a constant proton RBE.
Evaluation of ion recombination and polarity effect on photon depth dose measurements using mini- and micro-ion chamber
Fogliata A, Bresolin A, Gallo P, La Fauci F, Pelizzoli M, Reggiori G and Cozzi L
To investigate the effect of ion recombination ( ) and polarity ( ) correction factors on percentage depth dose (PDD) curves for three ion chambers, using flat and flattening filter free (FFF) beams, across different broad field sizes. A method to assess these effects and their corresponding corrections is proposed.
Analysis of sagittal plane cine magnetic resonance imaging for measurement of pancreatic tumor residual motion during breath hold and evaluation of gating margins used in radiotherapy treatment
Phipps A, Robinson M, George B and Whyntie T
In pancreatic radiotherapy, residual tumor motion during treatment increases the risk of toxicity. Cine imaging acquired during magnetic resonance guided radiotherapy (MRgRT) enables real-time treatment gating in response to anatomical motion, which can reduce this risk; however, treatment gating can negatively impact the efficiency of treatment. This study aimed to quantify the extent of residual tumor motion during breath hold and evaluate the appropriateness of the treatment gating margins used in current clinical practice.
Machine learning in image-based outcome prediction after radiotherapy: A review
Yuan X, Ma C, Hu M, Qiu RLJ, Salari E, Martini R and Yang X
The integration of machine learning (ML) with radiotherapy has emerged as a pivotal innovation in outcome prediction, bringing novel insights amid unique challenges. This review comprehensively examines the current scope of ML applications in various treatment contexts, focusing on treatment outcomes such as patient survival, disease recurrence, and treatment-induced toxicity. It emphasizes the ascending trajectory of research efforts and the prominence of survival analysis as a clinical priority. We analyze the use of several common medical imaging modalities in conjunction with clinical data, highlighting the advantages and complexities inherent in this approach. The research reflects a commitment to advancing patient-centered care, advocating for expanded research on abdominal and pancreatic cancers. While data collection, patient privacy, standardization, and interpretability present significant challenges, leveraging ML in radiotherapy holds remarkable promise for elevating precision medicine and improving patient care outcomes.
Clinical commissioning and introduction of an in-house artificial intelligence (AI) platform for automated head and neck intensity modulated radiation therapy (IMRT) treatment planning
Li X, Sheng Y, Wu QJ, Ge Y, Brizel DM, Mowery YM, Yang D, Yin FF and Wu Q
To describe the clinical commissioning of an in-house artificial intelligence (AI) treatment planning platform for head-and-neck (HN) Intensity Modulated Radiation Therapy (IMRT).
Development and validation of a questionnaire on radiation protection knowledge, attitudes, and practices among Moroccan dentists
Elmorabit N, Obtel M, Azougagh M, Marrakchi A and Ennibi OK
This study aimed to develop and evaluate the validity and reliability of dentists' radiation protection knowledge, attitudes, and practices (DRP-KAPs) questionnaire.
Surrogate gating strategies for the Elekta Unity MR-Linac gating system
Rusu SD, Smith BR, St-Aubin JJ, Shaffer N and Hyer DE
MRI-guided adaptive radiotherapy can directly monitor the anatomical positioning of the intended target during treatment with no additional imaging dose. Elekta has recently released its comprehensive motion management (CMM) solution that enables automatic radiation beam-gating on the Unity MR-Linac. Easily visualized targets that are distinct from the surrounding anatomy can be used to drive automatic gating decisions from the MRI cine imaging. However, poorly visualized targets can compromise the tracking and gating capabilities and may require surrogate tracking structures. This work presents strategies to generate robust tracking surrogates for a variety of treatment sites, enabling a wider application of CMM.
Enhancing safety: Multi-institutional FMEA and FTA on -based radio-pharmaceutical therapy
George SC, Aguirre S, Maughan NM, Tolakanahalli R, Samuel EJJ, Gallo SL, Zoberi JE and Lee YC
This study investigates potential failure modes and conducts failure mode and effects analysis (FMEA) and fault tree analysis (FTA) on the administration of DOTATATE (LUTATHERA) and PSMA-617 (PLUVICTO). The quality management (QM) process in radiopharmaceutical therapies (RPTs) requires collaboration between nuclear medicine (NM) and radiation oncology (RO) departments. As part of a multi-institutional study, we surveyed various departments to identify and analyze failure modes, leading to a proposed comprehensive QM program. RPT teams in RO or NM clinics can benefit from this study by continually improving their practice.
Deep learning based ultra-low dose fan-beam computed tomography image enhancement algorithm: Feasibility study in image quality for radiotherapy
Jiang H, Qin S, Jia L, Wei Z, Xiong W, Xu W, Gong W, Zhang W and Yu L
We investigated the feasibility of deep learning-based ultra-low dose kV-fan-beam computed tomography (kV-FBCT) image enhancement algorithm for clinical application in abdominal and pelvic tumor radiotherapy.
Attention 3D UNET for dose distribution prediction of high-dose-rate brachytherapy of cervical cancer: Intracavitary applicators
Gautam S, Osman AFI, Richeson D, Gholami S, Manandhar B, Alam S and Song WY
Formulating a clinically acceptable plan within the time-constrained clinical setting of brachytherapy poses challenges to clinicians. Deep learning based dose prediction methods have shown favorable solutions for enhancing efficiency, but development has primarily been on external beam radiation therapy. Thus, there is a need for translation to brachytherapy.
Supported bridge position in one-stop coronary and craniocervical CT angiography: A randomized clinical trial
Zhou H, Yan C, Ji M, Shi Z, Yang C and Zeng M
The routine patient arm position differs between coronary CT angiography (CTA) and craniocervical CTA protocols. To investigate the clinical feasibility of supported bridge position (SBP) in combined coronary and craniocervical CTA.
Three discipline collaborative radiation therapy (3DCRT) special debate: Systemic radiotherapy using targeted isotopes is the best hope for advancing curative radiation therapy
Koontz BF, Koritzinsky M, Zoberi JE, Brown SL, Ding X, Wong J, Joiner MC, Dominello MM and Burmeister J
Comparative analysis of fetal dose sparing between a C-arm linac and an O-ring linac in a SIB-VMAT sarcoma treatment for a pregnant patient: A technical note and case report
Rivais W, Constine L, Pacella M, Joyce N, Nagey M, Webster M, Yoon J, Jung H, Tanny S, Lemus OMD and Zheng D
To compare the effect of two linacs designs on fetal dose sparing on a pregnant patient, including estimation of the fetal dose, and the effect of a lead apron.
Introduction to matrix-based method for analyzing hybrid multidimensional prostate MRI data
Fan X, Chatterjee A, Medved M, Antic T, Oto A and Karczmar GS
A new approach to analysis of prostate hybrid multidimensional MRI (HM-MRI) data was introduced in this study. HM-MRI data were acquired for a combination of a few echo times (TEs) and a few b-values. Naturally, there is a matrix associated with HM-MRI data for each image pixel. To process the data, we first linearized HM-MRI data by taking the natural logarithm of the imaging signal intensity. Subsequently, a hybrid symmetric matrix was constructed by multiplying the matrix for each pixel by its own transpose. The eigenvalues for each pixel could then be calculated from the hybrid symmetric matrix. In order to compare eigenvalues between patients, three b-values and three TEs were used, because this was smallest number of b-values and TEs among all patients. The results of eigenvalues were displayed as qualitative color maps for easier visualization. For quantitative analysis, the ratio (λ) of eigenvalues (λ, λ, λ) was defined as λ = (λ/λ)/λ to compare region of interest (ROI) between prostate cancer (PCa) and normal tissue. The results show that the combined eigenvalue maps show PCas clearly and these maps are quite different from apparent diffusion coefficient (ADC) and T2 maps of the same prostate. The PCa has significant larger λ, smaller ADC and smaller T2 values than normal prostate tissue (p < 0.001). This suggests that the matrix-based method for analyzing HM-MRI data provides new information that may be clinically useful. The method is easy to use and could be easily implemented in clinical practice. The eigenvalues are associated with combination of ADC and T2 values, and could aid in the identification and staging of PCa.
Margin derivation from intrafraction patient motion of multi-target, single isocentre, brain stereotactic radiosurgery treatments
Caloz M, Tran S, Gau M, Romano E, Koutsouvelis N and Tsoutsou PG
Brain metastases are the most common intracranial malignancy and remain a substantial source of morbidity and mortality in cancer patients. Linear accelerator based stereotactic radiosurgery (SRS) is widely used and is frequently delivered by hypo-fractionnated volumetric modulated arc therapy using non-coplanar beams, where geometric accuracy and planning margins are a major concern.
Hyperparameter selection for dataset-constrained semantic segmentation: Practical machine learning optimization
Boyd C, Brown GC, Kleinig TJ, Mayer W, Dawson J, Jenkinson M and Bezak E
This paper provides a pedagogical example for systematic machine learning optimization in small dataset image segmentation, emphasizing hyperparameter selections. A simple process is presented for medical physicists to examine hyperparameter optimization. This is also applied to a case-study, demonstrating the benefit of the method.
Clinical target volume (CTV) automatic delineation using deep learning network for cervical cancer radiotherapy: A study with external validation
Wu Z, Wang D, Xu C, Peng S, Deng L, Liu M and Wu Y
To explore the accuracy and feasibility of a proposed deep learning (DL) algorithm for clinical target volume (CTV) delineation in cervical cancer radiotherapy and evaluate whether it can perform well in external cervical cancer and endometrial cancer cases for generalization validation.
Perspectives on program duration and research: A survey of graduates of a 3-year medical physics residency program
Hurwitz M, Gierga DP, Winey B, Zygmanski P, Kiger WS and Lyatskaya Y
The goal of this manuscript is to evaluate strengths and weaknesses of a 3-year medical physics residency program with the first year dedicated to research and the remaining 2 years dedicated to clinical training.
Replacing manual planning with automatic iterative planning for locally advanced rectal cancer VMAT treatment
Liu J, Wang R, Wang Q, Yao K, Wang M, Du Y, Yue H and Wu H
To develop and implement a fully automatic iterative planning (AIP) system in the clinical practice, generating volumetric-modulated arc therapy plans combined with simultaneous integrated boost technique VMAT (SIB-VMAT) for locally advanced rectal cancer (LARC) patients.
Assessing the robustness of dose distributions in carbon ion prostate radiotherapy using a fast dose evaluation system
Tsubouchi T, Shiomi H, Suzuki O, Hamatani N, Takashina M, Yagi M, Wakisaka Y, Ogawa A, Terasawa A, Akino Y, Ogawa K and Kanai T
We developed a software program for swiftly calculating dose distributions for carbon ion beams. This study aims to evaluate the accuracy of dose calculations using this software and assess the robustness of dose distribution in treating prostate cancer.
Dosimetric consequences of adapting the craniocaudal isocenter distance to daily patient position in craniospinal irradiation using volumetric modulated arc therapy
Heikkilä A, Vanhanen A, Rossi M, Koivumäki T, Postema M and Boman E
In craniospinal irradiation, two or three isocenter groups along the craniocaudal axis are required to cover the long treatment target. Adapting the isocenter distance according to daily deviations in patient position is challenging because dosimetric hot or cold spots may occur in the field junction. The aim of this study was to quantify the effect of adapting the isocenter distance to patient position on the dose distribution of the field overlap region in craniospinal irradiation using partial-arc volumetric modulated arc therapy.