UT Southwestern Medical Center

Monte Carlo (MC) methods are widely used for proton therapy dose calculation due to their high physical accuracy, but their stochastic nature results in statistical noise and long computation times, particularly for high-resolution dose calculations and itera...

Automating post-operative primary clinical target volume (CTV) segmentation in head and neck (H&N) cancers is challenging due to the surgical absence of the primary tumor and anatomical heterogeneity. Without the distinct radiographic boundaries of a gross tu...

For BgRT treatment on the RefleXion X1 linac, patients must meet stringent criteria regarding the proximity and 18F-FDG activity of OARs near the target. The next-generation X2 platform has an increased PET field of view, and new planning, PET detection, and...

To evaluate the feasibility and accuracy of surface-guided radiotherapy (SGRT) for setup and intrafraction motion monitoring in routine brain IMRT using open-face masks, and to assess whether immobilization device type affects monitoring performance.

Treating multiple oligometastatic lesions typically requires creating separate SBRT plans, resulting in longer treatment time and an increase in planning complexity. In this work we evaluate biology-guided multi-target treatment (MTT) approach for a PET-linea...

T1-weighted (T1w) and T2-weighted (T2w) FLAIR MRI provide complementary image contrast for delineating gross tumor volume (GTV) and clinical target volume (CTV) in brain tumor radiotherapy (RT) planning during both MRI simulation (MR-Sim) and MRI-guided RT (M...

Rectal spacers are widely used in prostate stereotactic ablative radiotherapy (SAbR) to reduce rectal dose; however, their value as a practical, planning-oriented QA tool remains underdefined. Using real-world clinical trial data, this study evaluates whether...

Therapy Physics

The ability to monitor and manage target motion in real time is rapidly becoming a cornerstone of precision radiation therapy. As institutions expand adaptive treatment programs, hypofractionation, and tighter margins, the clinical demand for robust motion ma...

Many foundational studies in our field were conducted using non-diverse populations, leading to biases in findings and the development of protocols that may not serve all patients equitably. Consequently, patients excluded from these research cohorts may expe...

Therapy Physics

The American Association of Physicists in Medicine has sponsored two summer undergraduate research programs since 2001: the Summer Undergraduate Fellowship Program (SUFP) and the Diversity Recruitment through Education and Mentoring Program (DREAM) programs....

This study aims to investigate the develop ultra-high-dose-rate (UHDR) proton FLASH spatially-fractionated-radiation-therapy (FLASH-SFRT) irradiations on a compact proton synchrocyclotron for preclinical experiments.

Brachytherapy, as a specialized subfield within radiation oncology, demands rigorous education, hands-on training, and substantial clinical experience. Its technical complexities and the risks associated with treatment delivery underscore the need for standar...

Therapy Physics

Safe and effective reirradiation depends on accurate cumulative dose assessment and consistent reporting of prior treatments. Current practices for dose accumulation vary widely across Canadian institutions, leading to inconsistencies in cumulative organ-at-r...

Medical physicists go through several failures in their career path, from student life to clinical or research training to being a staff of faculty. The mistakes/screw ups are learning experience for the individual or their local team but can also be a teachi...

Carbon ion radiotherapy (CIRT) offers high LET and RBE for treating radioresistant tumors but suffers from biological dose inhomogeneity due to RBE uncertainties. Techniques like LET painting focus on optimizing LET but do not directly address biological effe...

Direct-to-Unit (simulation-omitted) radiotherapy enables treatment planning directly from diagnostic imaging, eliminating CT simulation and supporting same-day treatment for time-sensitive cases. These workflows rely on adaptive radiotherapy (ART) platforms t...

Photon-counting CT (PCCT) denoising seeks to approximate high-dose image quality from lower-dose acquisitions. A key challenge for patient-specific denoising with precise control of denoising strength is the lack of an available ground-truth “target” image wh...

Motion management plays a critical role in radiation therapy for thoracic and abdominal tumors, where respiratory motion can significantly compromise treatment precision. Among available motion-mitigation techniques, respiratory gating offers distinct advanta...

The increasing adoption of MRI-guided online adaptive radiotherapy (oART) has improved treatment personalization but introduced substantial technical complexity and time pressure. Existing QA approaches remain largely manual and retrospective, with limited ab...

FLASH radiation therapy, which utilizes FLASH effect with ultra-high-dose-rate (UHDR) radiation, has shown promising performance in achieving treatment goals with decreased risks on healthy organs of patients. However, a number of factors, including patient-s...

Implicit neural representations (INRs) enable continuous, resolution-agnostic modeling of complex anatomical motion and have shown remarkable promise for deformation-driven, instance-specific real-time volumetric MRI estimation from a prior MRI. However, trai...

To develop a practical and simple method for estimating beam-on delay associated with respiratory-gated radiotherapy and validating the accuracy of the estimated delays

CT reference levels are mandated by Texas state regulations, and Medical Physics is responsible for reviewing CT studies that exceed these levels and determining the cause. The current clinical reference level for body CT, 60mGy, is applied uniformly across a...

For proton spots to be deliverable, the intensity of each spot must either be zero or exceed a specific minimum monitor unit (MMU) threshold, which is a nonconvex problem. This study develops a quantum computing (QC)-based optimization framework to address th...

Beam angle optimization (BAO) is a critical component of radiation therapy (RT) treatment planning, particularly for proton therapy, where small variations in beam configuration can substantially affect plan quality. BAO is naturally formulated as a mixed-int...

Proton LATTICE (pLATTICE) therapy delivers spatially heterogeneous dose distributions with high‑dose peaks embedded within low‑dose valleys. Conventional pLATTICE planning typically uses multiple beam angles per peak, making peak localization vulnerable to pr...

Clinical trials require the extraction of specific metrics from DICOM plan datasets for protocol-driven data analysis. Because these metrics vary widely across trials, it has been difficult to develop an automated system capable of supporting diverse study re...

Patient coaching on the Elekta Unity MR-Linac is challenged by an enclosed bore that limits direct observation and by high acoustic noise during MR imaging that can reduce comprehension of verbal commands. We developed a synchronized, dual-interface visual co...

To develop a WEb-Accessible comprehensiVE (WEAVE) platform, that combines AI-driven segmentation with a user-friendly interface to automatically segment Vestibular Schwannomas (VS) and track longitudinal volumes for disease assessment, planning, and monitorin...

Accurate tissue characterization is critical for adaptive proton therapy. This study evaluates the performance of relative electron density (RED) and stopping power ratios (SPR) predicted by virtual monoenergetic images (VMIs) derived from dual-energy CBCT (D...

In intensity-modulated proton therapy (IMPT), spot positions are conventionally fixed on uniform grids, and optimization is limited to spot weights. This constraint can restrict achievable dose conformity and increase the number of spots required to meet clin...

Accurate estimation of microstructural parameters by Imaging Microstructural Parameters Using Limited Spectrally Edited Diffusion (IMPULSED) diffusion MRI, including cell size and intracellular volume fraction, is promising for monitoring radiation treatment...

Visual assessment of ultrasound uniformity is subjective and prone to inter-observer variability. This study validates a novel, automated metric combining weighted intensity statistics and texture analysis to provide an objective, continuous scale for uniform...

To address fragmentation and variability in longitudinal brain lesion assessment, we developed Brain-Dynamics, a vendor-neutral platform integrating auto‑segmentation, multimodal co‑registration, lesion labeling/tracking, and quantitative analytics for resear...

The Russian invasion of Ukraine has significantly disrupted radiation therapy (RT) services, highlighting the urgent need to replace Cobalt-60 machines and modernize infrastructure and training across 43 RT centers. In response, Help Ukraine Group (HUG) and R...

Cone-beam CT (CBCT) acquired on the linear accelerator is being increasingly used beyond image guidance to support simulation and treatment planning workflows. This work reports the clinical implementation, challenges, and solutions associated with CBCT-based...

Dual‑source photon‑counting CT (DS‑PCCT) enables fast FLASH acquisition combined with spectral imaging—capabilities not available in single‑source PCCT (SS‑PCCT). This study evaluates whether DS‑PCCT maintains quantitative accuracy by comparing CT number and...

To clinically validate an implicit neural representation (INR)-based fitting approach for intravoxel incoherent motion (IVIM) diffusion MRI parameter estimation against conventional non-linear least squares (NLLS), and to evaluate a robustness metric (R-index...

Combination radiopharmaceutical therapy (RPT) and external beam radiation therapy (EBRT) is an underexplored strategy that may improve outcomes over either modality alone; however, practical implementation requires a clear understanding of dosimetry and radia...

Positron Emission Tomography/Computed Tomography (PET/CT) plays a pivotal role in radiation therapy, particularly in tumor delineation, response assessment, and adaptive therapy planning. However, the reliability of PET/CT depends on key system performance an...

Diffusion-weighted MRI (DWI) and its derived parameters, including apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM) metrics, are valuable for assessing tumor response to radiotherapy. However, DWI processing workflows are complex,...

In MR-only radiotherapy planning (MROP), limited field-of-view (LFOV) acquisition and imaging artifacts can introduce truncated anatomy and density inaccuracies, reducing the reliability of dose calculation and preventing comprehensive plan evaluation due to...

Photon-counting detector (PCD)–based cone-beam CT (CBCT) is gaining increasing interest for its potential to enable high-resolution and spectrally rich imaging. This study develops a tabletop PCD-CBCT system as a research platform and reports our progress in...

Simulation-omitted prostate SBRT (SO-PRO) has potential to reduce treatment delays and expand access to care but presents unique challenges for SBRT workflows that require careful management of target and organ-at-risk (OAR) dose. A major barrier is diagnosti...

DeepTuning is a deep learning–based dose prediction framework that generates multiple dose distributions with different trade-offs, analogous to multi-criteria optimization. Leveraging historical cases with varying trade-offs, DeepTuning extracts semantic tra...

To develop an AI agent framework leveraging large language models (LLMs) for intelligent data extraction and reasoning over radiation oncology data from oncology information systems (OIS) and electronic medical records (EMR), enabling patient-specific queries...

One major bottleneck in MRI-guided online adaptive radiotherapy is the prolonged treatment process, particularly extended delivery times, partly due to the relatively low dose rate and high prescription doses. Efficient radiation delivery is essential for mai...

Amid ongoing war, Ukraine continues to maintain and modernize radiation therapy (RT) services. Between 2023 and 2025, 24 linacs were installed to replace aging, non-rechargeable cobalt units. While linacs offer clinical advantages, they require stringent dosi...

Accurate prediction of overall survival (OS) in glioblastoma (GBM) remains challenging in clinical practice. Recently developed foundation models trained on large-scale medical imaging datasets offer a promising strategy to improve downstream clinical predict...

CBCT-based online adaptive radiotherapy (CBCT-oART) enables daily plan adaptation but is sensitive to intra-fraction motion during extended adaptive workflows. This study evaluates breath-hold (BH) motion stability and workflow impact using an in-bore surface...

Proton PBS treatment planning relies on iterative numerical optimization and is time-consuming. Deep learning enables rapid inference and therefore has the potential for fast prediction of beamlet intensities from anatomical imaging inputs (e.g., CT voxels an...

Magnetic resonance (MR)–only radiotherapy planning requires accurate synthetic CT (sCT) generation from images acquired using standard clinical MRI simulation protocols. However, MRI acquisition protocols vary substantially across anatomical sites, and many e...

Weisskoff analysis assesses temporal stability of echo-planar imaging (EPI) in functional MRI (fMRI) by comparing how the temporal coefficient of variation (CoV) scales with ROI size relative to uncorrelated noise (e.g. ideal scaling) to assess unwanted inter...

Online adaptive prostate MR-guided radiotherapy (MRgRT) is time-sensitive, and contouring with structure preparation can require upwards of 15 minutes per fraction. While vendor-TPS provided contours can be useful, performance and consistency vary by site, pr...

Stereotactic ablative radiotherapy (SAbR) achieves high local control in patients with oligometastatic renal cell carcinoma (omRCC), but a subset of patients experience early progression due to occult micrometastatic disease and may not benefit from an oligom...

Photon-counting CT (PCCT) incorporates detector technology that supports quantitative imaging in routine diagnostic evaluation by reducing scanner- and patient-specific effects, thereby enabling more reliable material quantification and characterization. Prev...

To provide AAPM members with a centralized, authoritative, and continuously updated web-based resource for obtaining beam quality conversion factors, kQ, and other data needed to realize absorbed dose measurements using the AAPM TG-51 protocol.

Conventional intensity-modulated proton therapy (IMPT) planning commonly relies on fixed, uniformly distributed spot grids with optimization restricted to spot weights. Although adaptive spot placement has been explored to improve dose conformity, particularl...

Cancer treatment planning requires clinicians to rapidly synthesize complex clinical information from detailed patient notes, a process that is time-consuming and cognitively demanding, particularly in multidisciplinary workflows involving non-physician clini...

Magnetic resonance imaging-guided online adaptive radiotherapy (MRgRT) requires a complex planning process, during which an upstream peer review prior to physician approval plays an essential role in early error detection and supporting safe and efficient onl...

Lattice radiotherapy (LATTICE) is a spatially fractionated technique that delivers high doses to discrete peak regions within the target while maintaining lower doses in surrounding valley regions, yielding a high peak-to-valley dose ratio (PVDR). Conventiona...

Lattice radiotherapy (LRT) is a spatially fractionated radiation technique that creates three-dimensional arrays of high-dose vertices within tumor volumes. Current LRT implementations face geometric constraints in small and medium-sized tumors, primarily due...

Ring artifacts were observed on our photon-counting CT (PCCT) daily quality control images, with 40 keV virtual monoenergetic images (VMIs) exhibiting the most pronounced artifacts. Because these artifacts may reflect degraded system stability and detector pe...

To compare MR-simulation motion emulation with measured respiratory gating performance for ultra-central lung treatments on 1.5T MR-linac and to identify the dominant factors affecting gating efficiency. The study focuses on the role of tracking surrogate sel...

Proton arc therapy (PAT) holds promise for enhancing plan conformity while minimizing dose sparing. However, PAT faces practical barriers related to delivery inefficiency, and its effectiveness can be compromised by beam range and radiobiological uncertaintie...