The purpose of this study was twofold: (a) report the long‐term monthly quality assurance (QA) dosimetry results of the uniform scanning beam delivery system, and (b) derive the machine‐specific tolerances based on the statistic process control (SPC) methodology and compare them against the AAPM TG224 recommended tolerances.

We propose a novel understanding of two characteristics of the planning target volume (PTV) that affect the intermediate‐dose spill in lung stereotactic body radiation therapy (SBRT) as measured by R50%. This phantom model research investigates two characteristics of the PTV that have a marked effect on the value of R50%: the mean dose deposited within the PTV (Dav) and the surface area of the PTV

To develop a customized method to produce uniform phantoms for task‐based assessment of CT image quality.

The American population is without question suffering from fatigue. The stress of this ongoing pandemic has resulted in many Americans making the decision to return to normalcy as restrictions are easing in most states. In Kentucky as of early June, less than half of grocery and retail store patrons are complying with wearing face coverings in public. Retail outlets requiring face coverings are enduring

1 INTRODUCTION Radiomics, the high‐throughput extraction and analysis of features from medical images, is a promising field for characterizing tumor phenotype and normal tissue injury post‐radiotherapy. Radiomics provides unique opportunities to identify predictive and prognostic imaging biomarkers in noninvasive imaging assays providing so‐called digital biopsies that can be acquired throughout the

This work investigates the incorporation of fiducial marker‐based visibility parameters into the optimization of volumetric modulated arc therapy (VMAT) plans. We propose that via this incorporation, one may produce treatment plans that aid real‐time tumor tracking approaches employing exit imaging of the therapeutic beam (e.g., via EPID), in addition to satisfying purely dosimetric requirements. We

To identify causes of error, and present the concept of an automated technique that improves efficiency and helps to reduce transcription and manual data entry errors in the treatment planning of total body irradiation (TBI).

To investigate the dosimetric impact of magnetic (B) field on varying air cavities in rectum patients treated on the hybrid 1.5 T MR‐linac.

MR image‐guided radiotherapy has the potential to improve patient care, but integration of an MRI scanner with a linear accelerator adds complexity to the commissioning process. This work describes a single institution experience of commissioning an Elekta Unity MR‐linac, including mechanical testing, MRI scanner commissioning, and dosimetric validation. Mechanical testing included multileaf collimator

Radiation effective dose to the red bone‐marrow, a critical organ in the therapy of differentiated thyroid carcinoma (DTC) with radioiodine‐131 (131I), cannot be measured directly. As radioiodine concentration is comparable in blood and most organs, and is believed to be similar in red marrow, the effective dose to the blood seems to be a good first‐order approximation of the radiation effective dose

The COVID‐19 pandemic has led to disorder in work and livelihood of a majority of the modern world. In this work, we review its major impacts on procedures and workflow of clinical physics tasks, and suggest alternate pathways to avoid major disruption or discontinuity of physics tasks in the context of small, medium, and large radiation oncology clinics. We also evaluate scalability of medical physics

Radiation protective apparatus is normally specified in "millimeter" of lead equivalence. Typically, it is less than 0.5 mmPb with the exception of lead eyeglasses, which may be 0.75 mmPb equivalent. Upon discovery of commercially available lead foil tape, manufactured by 3M™ "Lead Foil Tape 421" (LFT) which is designed for industrial utility applications. We set out to determine if this LFT can, indeed

To compare dose to the targets and organs at risk (OARs) in different situations for postmastectomy patients who require radiation to the chest wall with or without regional nodal irradiation when using three treatment techniques.

To measure the scattered x‐rays of megavoltage (MV) and kilovoltage (kV) beams (MV scatter and kV scatter, respectively) on the orthogonal kV imaging subsystems of Vero4DRT.

Along with the increasing demand for high‐quality radiotherapy and the growing number of high‐precision radiotherapy devices, precise radiotherapy workflow management and accurate time evaluation of the entire radiotherapy process are crucial to providing appropriate, timely treatment for cancer patients. This study therefore aimed to establish an accurate, reliable method for evaluating the duration

Several dual‐energy computed tomography (DECT) techniques require a deformable image registration to correct for motion between the acquisition of low and high energy data. However, current DECT software does not provide tools to assess registration accuracy or allow the user to export deformed images, presenting a unique challenge for image registration quality assurance (QA). This work presents a

The number of dose‐limiting shells in the optimization process is one of the key factors determining the quality of stereotactic body radiotherapy (SBRT) auto‐planning in the Pinnacle treatment planning system (TPS). This study attempted to derive the optimal number of shells by evaluating the auto‐plans designed with different number of shells for peripheral lung cancer patients treated with SBRT

The Radixact® linear accelerator contains the motion Synchrony system, which tracks and compensates for intrafraction patient motion. For respiratory motion, the system models the motion of the target and synchronizes the delivery of radiation with this motion using the jaws and multi‐leaf collimators (MLCs). It was the purpose of this work to determine the ability of the Synchrony system to track

In the article cited above, clarifications have been made in three places as listed below. Introduction, lines 21‐22: The phrase “examined the coordination between GS and relative dose profiles” Has been changed to “studied the dose control and GS” Introduction, lines 26–27: The phrase “Further, the measured parameters were not evaluated as a function of gantry angle” Has been changed to “The relative

Single‐isocenter multiple brain metastasis stereotactic radiosurgery is an efficient treatment modality increasing in clinical practice. The need to provide accurate, patient‐specific quality assurance (QA) for these plans is met by several options. This study reviews some of these options and explores the use of the Octavius 4D as a solution for patient‐specific plan quality assurance.

To report our experience of combining three approaches of an automatic plan integrity check (APIC), a standard plan documentation, and checklist methods to minimize errors in the treatment planning process.

We aimed to estimate the risk of secondary cancer after radiotherapy (RT) in high‐risk prostate cancer (HRPC) patients with pelvic irradiation. Computed tomography data of five biopsy‐proven HRPC patients were selected for this study. Two different planning target volumes (PTV1 and PTV2) were contoured for each patient. The PTV1 included the prostate, seminal vesicles, and pelvic lymphatics, while

The purpose of this work is to develop a procedure for commissioning four‐dimensional computed tomography (4DCT) algorithms for minimum target reconstruction size, to quantify the effect of anterior–posterior (AP) motion artifacts on known object reconstruction for periodic and irregular breathing patterns, and to provide treatment planning recommendations for target sizes below a minimum threshold

The purpose of this study was to investigate the effect of increasing iterative reconstruction (IR) algorithm strength at different tube voltages in coronary computed tomography angiography (CCTA) protocols using a three‐dimensional (3D)‐printed and Catphan® 500 phantoms.

To improve the efficiency of computed tomography (CT)‐magnetic resonance (MR) deformable image registration while ensuring the registration accuracy.

Although notched Collaborative Ocular Melanoma Study (COMS) plaques have been widely used, optic disc dose reduction by notched COMS plaques has not been discussed in the literature. Therefore, this study investigated optic disc dose reduction in ocular brachytherapy using 125I notched COMS plaques in comparison with optic disc dose for 125I standard COMS plaques.

The SARS‐CoV‐2 coronavirus pandemic has spread around the world including the United States. New York State has been hardest hit by the virus with over 380 000 citizens with confirmed COVID‐19, the illness associated with the SARS‐CoV‐2 virus. At our institution, the medical physics and dosimetry group developed a pandemic preparedness plan to ensure continued operation of our service. Actions taken

Daily output variations of up to ±2% were observed for a protracted time on a Varian TrueBeam® STx; these output variations were hypothesized to be the result of atmospheric communication of the sealed monitor chamber. Daily changes in output relative to baseline, measured with an ionization chamber array (DQA3) and the amorphous silicon flat panel detector (IDU) on the TrueBeam®, were compared with

1 Overview Medical big data science research such as radiomics has soared in recent years and found many potential applications in medical physics. In contrast to the tremendous interests in these exciting new directions, comprehensive learning materials and books have been scarce on these topics, especially those that tailor toward the radiation oncology and radiology communities. Despite an abundance

This work introduces a novel capacitive‐sensing technology capable of detecting respiratory motion with high temporal frequency (200 Hz). The system does not require contact with the patient and has the capacity to sense motion through clothing or plastic immobilization devices.

The purpose of this study is to predict the collision clearance distance of stereotactic cones with treatment setup devices in cone‐based stereotactic radiosurgery (SRS). The BrainLAB radiosurgery system with a Frameless Radiosurgery Positioning Array and dedicated couch top was targeted in this study. The positioning array and couch top were scanned with CT simulators, and their outer contours of

The implementation and evaluation of an in‐house developed geometry optimization (GO) software are described. The GO script provides optimal lesion clustering, isocenter placement, and collimator angle of each arc for cranial multi‐lesion stereotactic radiosurgery (SRS) volumetric modulated arc therapy (VMAT) planning.

To evaluate the clinical feasibility and dosimetric benefits of a novel gantry‐static couch‐motion (GsCM) technique for external beam photon boost treatment of lumpectomy cavity in patients with early‐stage breast cancer in comparison to three‐dimensional conformal radiotherapy (3D‐CRT), wedge pair in supine position (WPS), and wedge pair in decubitus position (WPD) techniques. A retrospective review

The heavy‐ion medical machine (HIMM), which is the first commercial medical accelerator designed and built independently by the institute of modern physics (IMP) in Wuwei, Gansu Province, China, had officially completed clinical trials at the time of this article's writing. Three types of detector systems were developed based on the ionization‐chamber principle to monitor the beam parameters during

Three‐dimensional computed tomographic angiography (3D‐CTA) is widely used to evaluate the inner diameters of vessels and the anatomical vascular structure prior to endoscopic aortic surgery or transcatheter valve implantation. Virtual monoenergetic imaging (VMI) is a new application in dual‐energy CT (DECT). We evaluated the potential for contrast dose reduction in preoperative aortic CTA using VMI

Radiotherapy of mobile tumors requires specific imaging tools and models to reduce the impact of motion on the treatment. Online continuous nonionizing imaging has become possible with the recent development of magnetic resonance imaging devices combined with linear accelerators. This opens the way to new guided treatment methods based on the real‐time tracking of anatomical motion. In such devices

To evaluate the dosimetric effects of the AeroFormTM (AirXanpders®, Palo Alto, CA) tissue expander in‐situ for breast cancer patients receiving post‐mastectomy radiation therapy.

To develop an efficient and automated methodology for beam data validation for a preconfigured ring gantry linear accelerator using scripting and a one‐dimensional (1D) tank with automated couch motions.

Frameless Gamma Knife stereotactic radiosurgery (SRS) uses a moldable headrest with a thermoplastic mask for patient immobilization. An efficacious headrest is time consuming and difficult to fabricate due to the expertise required to mold the headrest within machine geometrical limitations. The purpose of this study was to design and validate a three‐dimensional (3D)‐printed headrest for frameless

The coauthors, Mary Beth Allen, MBA, PhD and Mehdi Mirsaeidi, MD, MPH, are my former colleagues from the University of Louisville and both have significant experience and expertise regarding infectious disease. Dr. Allen is a healthcare research consultant and former senior program manager for infectious disease at the University of Louisville. Dr. Mirsaeidi is currently an Associate Professor at the

1 Three Discipline Collaborative Radiation Therapy (3DCRT) Debate Series Radiation Oncology is a highly multidisciplinary medical specialty, drawing significantly from three scientific disciplines — medicine, physics, and biology. As a result, discussion of controversies or changes in practice within radiation oncology must involve input from all three disciplines. For this reason, significant effort

The tracheostomy site and adjacent skin is at risk for recurrence in head/neck squamous cell cancer patients. The tracheostomy tube is an in situ device located directly over the tracheostomy site and may have clinical implications on the radiation dose delivered to the peristomal region. This study aimed to investigate this effect by comparing the prescribed treatment planning dose with the actual

Segmentation of organs‐at‐risk (OARs) is an essential component of the radiation oncology workflow. Commonly segmented thoracic OARs include the heart, esophagus, spinal cord, and lungs. This study evaluated a convolutional neural network (CNN) for automatic segmentation of these OARs.

This study was designed to evaluate skin dose in both VMAT and tangent treatment deliveries for the purpose of identifying suitable bolus use protocols that should produce similar superficial doses.

In this study, we have quantified the setup deviation and time gain when using fast surface scanning for daily setup/positioning with weekly megavoltage computed tomography (MVCT) and compared it to daily MVCT.

To apply failure mode and effect analysis (FMEA) to generate an effective and efficient initial physics plan checklist.

To assess the accuracy of volumetric modulated arc therapy (VMAT) stereotactic body radiation therapy (SBRT) when treating moving targets (such as lung or liver lesions), focusing on the impact of the interplay effect in the event of complex breathing motion and when a gating window is used.

1 INTRODUCTION One type of cosmetic that has gained recent popularity is the magnetic false eyelash. Some of these magnetic eyelashes are placed onto magnetic eyeliner applied to eye lids, while others come in pairs and clamp around the natural eyelashes. This presents potential safety hazards in the magnetic resonance imaging (MRI) environment. This is because patients may not deem it necessary to

In radiotherapy, a trade‐off exists between computational workload/speed and dose calculation accuracy. Calculation methods like pencil‐beam convolution can be much faster than Monte‐Carlo methods, but less accurate. The dose difference, mostly caused by inhomogeneities and electronic disequilibrium, is highly correlated with the dose distribution and the underlying anatomical tissue density. We hypothesize

To validate the dose measurements for two total skin irradiation techniques with Monte Carlo simulation, providing more information on dose distributions, and guidance on further technique optimization.

Noncoplanar radiotherapy can provide significant dosimetric benefits. However, clinical implementation of such techniques is not fully realized, partially due to the absence of a collision prediction tool integrated into the clinical workflow. In this work, the feasibility of developing a collision prediction system (CPS) suitable for integration into clinical practice has been investigated.

Cone‐beam computed tomography (CT)‐guided volumetric‐modulated arc therapy (VMAT) plans for stereotactic body radiotherapy (SBRT) treatment of synchronous multiple lung lesions with a flattening filter‐free (FFF) beam is a safe and highly effective treatment option for oligometastases lung cancer patients. Fourteen patients with metastatic non–small‐cell lung cancer (NSCLC) lesions (two to five) received

During the current coronavirus COVID‐19 pandemic, remote interpretation of medical images, such as viewing studies from home, has become imperative for facilities to achieve their social‐distancing mandate and provide a safe workplace for image interpreters. To insure accurate interpretation of studies, it is self‐evident that monitors used for image interpretation, which we will refer to as primary

A proton therapy system with 190° gantries uses robotic couch rotations to change the treatment beam laterality. Couch rotations are typically validated clinically with post‐rotation radiographic imaging.

A predictive linac quality assurance system based on the output of the Machine Performance Check (MPC) application was developed using statistical process control and autoregressive integrated moving average forecast modeling. The aim of this study is to demonstrate the feasibility of predictive quality assurance based on MPC tests that allow proactive preventative maintenance procedures to be carried

Intrafraction imaging‐based motion management systems for external beam radiotherapy can rely on internal surrogate structures when the target is not easily visualized. This work evaluated the validity of using liver vessels as internal surrogates for the estimation of liver tumor motion. Vessel and tumor motion were assessed using ten two‐dimensional sagittal MR cine datasets collected on the ViewRay

To provide insight into the types of questions asked to medical physicists by patients during one‐on‐one physicist–patient consults at one institution.

Most clinical computed tomography (CT) protocols use helical scanning; however, the traditional method for CTDIvol measurement replaces the helical protocol with an axial scan, which is not easily accomplished on many scanners and may lead to unmatched collimation settings and bowtie filters. This study assesses whether CTDIvol can be accurately measured with a helical scan and determines the impact

Imaging, breath‐holding/gating, and fixation devices have been developed to minimize setup errors so that the prescribed dose can be exactly delivered to the target volume in radiotherapy. Despite these efforts, additional patient monitoring devices have been installed in the treatment room to view patients’ whole‐body movement. We developed a facial expression recognition system using deep learning

This retrospective study was to compare the image quality of right coronary artery (RCA) and effective radiation dose on prospective ECG‐gated method between 320 row computed tomography (CT) and 2nd generation (128‐slice) dual source CT. A total of 215 candidates underwent CT coronary angiography using prospective ECG‐gated method, 120 patients enrolled in 320 row CT group, and 95 patients in dual