Stanford University

Radiopharmaceutical therapy (RPT) plays an important role in the management of oncology patients, particularly those with thyroid cancer, prostate cancer, and neuroendocrine tumor. The use of radionuclide therapy has expanded rapidly in recent years, with the...

Prior to clinical launch of the world’s first installation of MEVION S250-FIT combined with Marie® system we evaluated anatomical and dosimetric differences between conventional photon-based supine treatments and proton-based upright treatments for prostate c...

Cherenkov imaging (CI) provides direct, real-time visualization of dose on a patient's surface and has been used for treatment verification and error detection in radiation therapy. However, clinical adoption of CI remains in its infancy; existing image revie...

To develop and validate a unified multimodal medical foundation model that combines visual understanding, cross-modal generation (image-text translation), and interpretable reasoning with visual grounding, and to quantify the gains enabled by multi-objective...

To evaluate the ability of a RefleXion X2 system with extended PET-FOV with a developmental Anchor Point Tracking algorithm to autonomously follow PET-avid target and deliver dose, accounting for large sudden target displacements.

Sparse detector arrays commonly used for patient-specific radiotherapy quality assurance (QA) cannot provide complete spatial dose distribution measurements, leading to uncertainties particularly in high-gradient dose regions.The goal of this project is to de...

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...

Recent advances in nanophotonic engineering have enabled subwavelength nanostructures to be patterned onto conventional scintillating materials, significantly enhancing light yield by both amplifying and directing emission toward the detector. This study repr...

Therapy Physics

Deep learning-based image reconstruction has shown substantial promise for addressing the highly non-uniform and under-sampled projections encountered in nonstop gated CBCT (ngCBCT). However, due to the statistical nature of data-driven learning and inherent...

Radiotherapy treatment planning is a resource-intensive process characterized by multiple manual steps that can contribute to treatment delays and inter-observer variability. The Radiation Planning Assistant (RPA) is a web-based platform designed to deliver a...

Interstitial brachytherapy enables highly conformal radiotherapy, but accuracy depends on surgical skill, and few in vivo dosimetry systems exist. Effective monitoring requires not just dose but tracking source position, dwell time, and transit times. We deve...

The significant tissue-sparing advantages of upright proton therapy (UPT) make it an appealing treatment for pediatric patients, yet its widespread use is limited by the lack of a commercially available solution for upright anesthesia-assisted treatment. Addi...

Precise proton therapy treatment planning relies on the synergy between the superior soft-tissue definition obtained from MRI and the accurate relative stopping power (RSP) maps derived from CT. However, standard workflows that utilize separate scans are ofte...

Colorectal cancer (CRC) ranks as the third most diagnosed malignancy in the world. This study aims to investigate an automated, visually interpretable framework for intelligent identification and localization of the primary CRC in portal venous phase contrast...

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...

The MEVION S250-FIT introduces a novel fixed-gantry, upright patient positioning system, yet lacks commercial secondary dose calculation (SDC) tools necessary for clinical safety verification. While Monte Carlo (MC) simulations offer gold-standard accuracy, t...

Fast and accurate dose calculation is a key requirement for real-time adaptive radiotherapy, particularly for emerging image-guided radiation therapy systems. Monte Carlo methods and existing treatment planning system (TPS) algorithms do not achieve the compu...

Although most patients with Hodgkin lymphoma (HL) are cured with chemotherapy with or without immunotherapy, a subset fails to respond to first-line therapy. Baseline clinical factors alone do not reliably identify nonresponders. Baseline PET radiomic feature...

Biological systems are inherently structured, with genes and molecular components interacting through organized pathways and networks. Graph-based representations are therefore widely used in biological analysis. However, many existing deep learning approache...

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...

An improved imager and software (HyperSight on a Varian TrueBeam linac) feature a larger detector panel and increase the maximum gantry rotation speed for CBCT imaging to 1.5 revolutions per minute (rpm). While enabling faster acquisition, its impact on free-...

The clinical utility of low field MRI is limited by inherently low signal-to-noise ratio (SNR). Effective feature modeling plays a vital role in image denoising yet modeling long-range feature dependencies are computationally expensive. This study investigate...

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...

Longitudinal brain MRI enables analysis of anatomical changes associated with aging and neurodegenerative disease, yet interpreting structural evolution over time remains challenging due to subtle changes such as inter-subject heterogeneity, and variability a...

To develop a reliable batch‑calibration method and dose‑reading protocol for in-vivo scintillation imaging dosimetry during radiation therapy.

In non-coplanar SBRT/SRS, efficient high-resolution volumetric imaging under limited-angle non-coplanar CBCT (LA-NC-CBCT) acquisition is critical for avoiding potential collisions while ensuring treatment delivery accuracy. However, severe data occlusion outs...

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...

Clinical translation of FLASH requires treatment planning systems (TPS) capable of accurately modeling ultra-high dose rate delivery. For FLASH configurations on clinical machines, vendor-provided phase space files are not applicable, thus necessitating indiv...

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...

Upright radiotherapy offers physiological and dosimetric advantages. Mevion S250-FIT, world’s first clinical ultra-compact synchrocyclotron-based upright proton therapy system, incorporates a novel upright CT for treatment planning and image guidance. This st...

The RefleXion X1 system requires activity concentration (AC) >5 kBq/mL for successful biology-guided radiotherapy (BgRT). We evaluated whether the extended field-of-view (FOV) PET detector in a can lower this AC threshold and expand treatment eligibility.

To develop and validate a fully automated, cost-effective Field-in-Field (FiF) planning script within the Varian Eclipse Scripting API (ESAPI) environment. The project aims to improve the plan quality and efficiency for breast radiotherapy by leveraging Eclip...

To evaluate real-time, longitudinal performance of a commercial auto-segmentation model across a broad radiotherapy cohort and examine contour editing influence on planning decisions and organ-at-risk (OAR) doses, with attention to practice patterns, disease-...

Upright radiotherapy offers favorable physiological and geometric conditions compared with conventional supine delivery. However, posture-induced anatomical deformation complicates the alignment of supine diagnostic images with upright simulation and treatmen...

Deep silicon photon counting CT can produce quantitative CT images with every scan, leveraging 8 energy bins to quantify material densities. This study evaluates the material decomposition (MD) and virtual monoenergetic image (VMI) accuracy of calcium and iod...

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...

To characterize the reproducibility and dosimetric stability of a 5-day fractionated preclinical irradiation protocol delivered on a clinical Varian TrueBeam linac operated under FLASH and conventional (CONV) settings.

Radiation therapy optimization problems frequently involve multiple competing objectives, requiring multi-objective optimization to navigate trade-offs. This work used a Non-dominated Sorting Genetic Algorithm (NSGA-II) optimizer to identify Pareto-optimal ge...

Configuring clinical linear accelerators (LINACs) for ultra-high dose rate (UHDR) electron experiments typically requires invasive hardware modification or manufacturer intervention, limiting accessibility. We developed an independent, non-invasive, software-...

While MR-guided radiotherapy enables real-time, soft-tissue–based motion management, clinical 2D cine MRI often sacrifices spatial resolution to maintain frame rate, which can contrast oncological contrast. This study aims to optimize a 2D cine MRI protocol o...

To assess the effectiveness of a developmental anchor point tracking algorithm with PET deblurring in targeting tumors on the RefleXion X2 platform.

Adaptive radiotherapy (ART) and personalized ultra‑fractionated stereotactic adaptive radiotherapy (PULSAR) require longitudinal anatomical modeling, deformable image registration (DIR), and dose recalculation and accumulation. While these capabilities are we...

High-dimensional genomic and clinical tabular data lack spatial structure, limiting the effectiveness and interpretability of modern deep learning. In medical physics, raw measurements are routinely transformed into structured physical representations (e.g.,...

Accurately modeling how organs move is essential in modern medical imaging and radiotherapy. Tasks such as deformable image registration (DIR), dose accumulation, motion tracking, and treatment adaptation all depend on reliable representations of anatomical d...

In Total Skin Electron Therapy (TSET) using the Stanford technique, the delivered dose is strongly affected by daily positioning uncertainties. This study presents an integrated framework that combines AI-assisted rapid generation of patient-specific six-post...

To quantify radiation induced glutathione (GSH) dynamics in A549 lung cancer cells using a ratiometric RealThiol (RT) probe and to assess microscopy and optical sensor platforms for real-time monitoring of redox responses following conventional and FLASH radi...

Overlapping tracks complicate particle classification and are unavoidable in pixelated semiconductor detectors due to their random nature. This study introduces a Hybrid Particle Track (HPT) net and a Simultaneous Track Energy And Length (STEAL) extension of...

The Mevion S250-FIT is the world’s first ultra-compact proton therapy system designed with a form factor compatible with existing LINAC vaults. This raises questions regarding radiation shielding adequacy and electromagnetic compatibility with adjacent radiot...

With improvements in patient outcomes, re-irradiation is increasingly pursued and is becoming a common occurrence in the clinic. Safe planning requires accurate characterization of cumulative organ-at-risk (OAR) exposure across treatment courses that may diff...

Deep learning–based glioma segmentation models are commonly developed under the assumption that the standard glioma MRI protocol—T1-weighted, contrast-enhanced T1 (T1ce), T2-weighted, and FLAIR—is available; however, this assumption may not hold in time-const...

To develop and characterize a lost-cost, 3D-printed, patient-specific electron cutout filled with steel ball bearings (BBs) for use with Elekta linear accelerators, and to assess current electron radiotherapy (ERT) practices and clinical perspectives on exist...

ZAP-X is a self-shielded radiosurgery system featuring a compact gyroscopic gantry design with kV imaging for patient setup and tracking. Its well-engineered treatment table and treatment-planning system allow lesions located inferiorly to remain treatable. H...

Diagnostic and Interventional Radiology Physics

Quality management at multicenter institutions takes on unique challenges when compared to that at standalone sites. With the trend towards institutions merging, the climate within several physics departments is taking on a new paradigm—quality assurance cann...

Therapy Physics

Leadership

Abstract: Since its publication in 2019, AAPM TG-203 has been used as a guide for physicists to assess the risks to cardiac implantable electronic devices (CIEDs) from radiation therapy treatments. There have been several new technological advances in radiati...

To develop FAST-X to deliver ultra-high dose-rate (UHDR) irradiation for complex cranial targets.

We developed a unified, fully automated, and open-source VMAT planning framework for three complex modalities: VMAT total body irradiation (VMAT-TBI), craniospinal irradiation (VMAT-CSI), and total marrow and lymphoid irradiation (VMAT-TMLI). The goal was to...

Numerous radioligand therapy (RLT) agents are under various stages of development for treating late-stage cancers. We developed a computational methodology for identifying promising targets for RLT based on spatial transcriptomics analysis of tumor tissue.

Total Skin Electron Irradiation (TSEI) is traditionally delivered with the patient standing at an extended source-to-surface distance, a position often intolerable for frail or compromised patients. While floor-based recumbent alternatives exist, they necessi...

Commissioning and performance validation of the world’s first ultra-compact upright proton therapy system and establish benchmarks for this novel treatment delivery paradigm.

Proton therapy offers superior dose conformity compared with photon therapy but remains limited by long delivery times and sensitivity to respiratory motion, particularly for thoracic tumors. Delivering an entire proton field within a short breath-hold (5–10s...

Therapy Physics

Radiotherapy plan quality education is limited by case availability, frequent clinical interruptions, and difficulty aligning schedules. These barriers leave residents underprepared to identify and correct suboptimal plans, potentially compromising future out...

To develop and evaluate a simulation-free, single-visit workflow for MRI-guided stereotactic ablative radiotherapy (SABR) for liver tumors using on-table imaging and online adaptive replanning, and to validate an MR-only dose calculation approach based on bul...

Imaging lies at the core of stereotactic radiosurgery (SRS), defining the geometric and biological precision required to safely deliver ablative doses to intracranial targets. Rapid advances in image acquisition, integration, and analysis are transforming eve...

Tumor hypoxia is a major driver of radiation resistance in solid tumors, yet its contribution to treatment response and metabolic reprogramming remains challenging to study using conventional models. This work proposes and validates a lung tumor-on-a-chip pla...

It can be a daunting task to start a new high-dose rate (HDR) or low-dose rate (LDR) brachytherapy program or to join an established program and realize updates are necessary. With many brachytherapy task groups and medical physics practice guidelines publish...

Therapy Physics

To examine the dose conformity during planning and delivery for complex C-shaped targets in an investigational RefleXion X2 platform under static and motion conditions.

The goal of this study is to accurately estimate 3D deformation and generate real-time volumetric images using only one or two X-ray projections, overcoming the limitations of ultra-sparse conditions in conventional deformable image registration (DIR) and vol...

The global prevalence of Parkinson’s disease (PD) is rising in tandem with a rapidly aging population. Transcranial sonography (TCS) has emerged as a promising tool for early diagnosis, as it is radiation-free, highly accessible, and cost-effective. Specifica...

Therapy Physics

Diagnostic and Interventional Radiology Physics

Secondary electron range constrains standard 6MV radiotherapy to 80%-20% dose penumbra of ~2.4–3 mm, limiting conformity and organ sparing. Photon FLASH likely necessitates even larger penumbra, which is potentially problematic as the dose rates can be non-FL...

Protoacoustic (PA) imaging enables real-time verification of proton dose deposition by reconstructing 3D initial pressure maps from acoustic signals generated during proton delivery. However, in practical treatment settings, detectors cannot fully surround th...

Ultra-high dose-rate (UHDR) radiotherapy has been reported to reduce normal tissue toxicity compared to conventional dose-rate irradiation (CDR), yet objective, quantitative imaging markers associated with this effect remain limited. This study evaluates whet...

Histopathology is essential for disease diagnosis and treatment decision-making. Recent advances in artificial intelligence (AI) have enabled the development of pathology foundation models that learn rich visual representations from large-scale whole-slide im...

Therapy Physics

In respiratory gating radiotherapy (RG-RT), pretreatment imaging—particularly gated cone-beam CT (gCBCT)—is essential but operationally inefficient. Current gCBCT on C-arm linear accelerator is time-consuming (2–8 minutes) and often requires re-scans when gat...

Accurately decoding the spatiotemporal complexities of the human brain requires capturing the intrinsic physical geometry of functional imaging data. Traditional dimensionality reduction methods often struggle with the non-linear, time-varying nature of the B...

To update U.S. national adult CT DRLs and ADs using 2025 data and to demonstrate a scalable, acquisition-level, size-normalized framework for generating timely and clinically relevant national benchmarks.

Nonstop gated CBCT (ngCBCT) was developed to overcome the limitations of current gated CBCT (gCBCT), enabling 2-8x faster acquisitions and 2.5-3.5x lower imaging dose. However, ngCBCT produces highly non-uniform and under-sampled projection data that challeng...

Traditional reliability analyses of linear accelerators (LINACs) have typically focused on individual components using limited datasets, failing to exploit the comprehensive operational insights contained within service logs. This study presents a novel, auto...

Medical imaging and molecular omics data provide complementary information about disease. Imaging describes tissue and organ structure, while omics measurements, e.g., gene expression, capture cellular and molecular processes. Integrating these data types is...

Collision risk between the patient/immobilization devices with gantry or the on-board imaging system remains a safety and workflow concern in modern radiotherapy. We built and implemented a real-time laser visualization system, enabling immediate assessment o...

Diagnostic and Interventional Radiology Physics

Professional

Task Group (TG) reports are without any doubt one of the most important scientific deliverables of the AAPM. The number of TG reports especially under Therapy Physics Committee (TPC) has exponentially increased the last few year. However, challenges and compl...

Current motion management systems are reactive: they detect patient displacement but require 200-400 ms to respond. This limitation prevents anticipatory intervention during breath-holds, forcing patients to their physiological limits before the system can re...