Brigham and Women's Hospital

To investigate whether the apparent diffusion coefficient (ADC) from diffusion-weighted imaging (DWI) acquired at a 0.35T MR-Linac can determine prostate and intraprostatic lesion changes caused by adaptive radiotherapy performed on this treatment modality.

Anatomic motion and deformation modeling using digital twins (DTs) hold much promise for radiotherapy applications. However, clinical implementation is limited by availability of high-quality data, computationally intensive and unphysical anatomical simulatio...

We compared denoising methods for Diffusion-Weighted Imaging (DWI) of phantoms acquired on a low-field MR-Linac to determine which method best preserves Apparent Diffusion Coefficient (ADC) accuracy and image feature detection. Our goal was to quantify image...

Cone beam CTs at typical kV energies exhibit metal artifacts in IGRT patients with metal prosthetics. MV-CBCT, available on some linacs, reduces artifacts at the expense of soft tissue contrast-to-noise (CNR). As a remedy, we propose an AI network to convert...

Accurate source positioning is essential for dose delivery in high-dose-rate (HDR) gynecologic (GYN) brachytherapy, necessitating routine applicator quality assurance (QA). This study introduces an applicator-specific, 3D-printed phantom with a quantitatively...

Preclinical studies combining radiation with gadolinium-based AGuIX nanoparticles show potent radiosensitization effect. However, physics simulations to date show a lack of macroscopic dose enhancement. We address this by shifting from absorbed dose (D) to mi...

Cognitive decline following brain radiotherapy is strongly associated with hippocampal injury, yet scalable methods for assessing treatment-related hippocampal structural change in clinical practice remain limited. This study evaluates hippocampal volume loss...

CT-based lung ventilation imaging can provide a functional assessment of tumor and normal tissue response to lung stereotactic body radiation therapy (SBRT). The speed of ventilation map generation hinders the clinical adoption of LVI for online adaptive SBRT...

To clinically implement and evaluate an MRI-only treatment planning (MRTP) workflow for interstitial high-dose-rate (HDR) brachytherapy in gynecologic cancers. In contrast to the conventional CT/MRI-based planning (CTP) approach, MRTP eliminates CT imaging, t...

During lung SBRT, tumor motion is managed using 4DCT-based ITV expansion, respiratory or external gating, or breath-hold techniques, each with limitations. Existing real-time tracking methods require implanted fiducials or additional imaging dose. A non-invas...

To quantify organ-at-risk (OAR) sparing achievable using a hybrid approach combining conventional image-guided radiotherapy (IGRT) with a CT-guided online adaptive radiotherapy (CT-ART) cone-down boost for pelvic malignancies.

Conventional radiotherapy dose (Gy) quantifies deposited energy, but response is influenced by the local radiochemical environment driving indirect DNA damage. Superoxide is a comparatively long-lived paramagnetic radical species showing potential as a marker...

To evaluate the clinical accuracy and utility of a commercial deep learning-based auto-segmentation tool by Siemens for delineating brain metastases (GTV) and organs-at-risk (OAR) on contrast-enhanced MRI.

PET imaging of positrons emitted during megavoltage radiotherapy has not been implemented due to concern of high-count rates. This computational study explores the feasibility of coincidence-counting experiments using two scintillators inside the linac vault...

To characterize the microsecond-scale dynamics of the free induction decay (FID) of a 0.35T Magnetic Resonance (MR)-guided Linear Accelerator (MR-Linac) during irradiation.

Limiting jaw position across midline is a common inverse-planning strategy to minimize dose to normal tissue and improve conformality when treating irregular targets. However, jawless linacs lack an analogous, planner-controlled method. In this study, we eval...

Adaptive MR-guided Stereotactic Body Radiation Therapy (MRg-SBRT) is an effective treatment for malignant pancreatic lesions. However, its implementation may be hindered by the presence of implants with scanning conditions interdicting body coil transmission...

Peer review is a core component of quality assurance in radiation oncology. This study evaluated whether physician years of clinical experience were associated with differences in peer review change rates within a standardized, prospective, disease-site–speci...

The efficacy of stereotactic radiosurgery (SRS) and radiotherapy (SRT) for brain metastases is often compromised by tumor growth and soft tissue changes between simulation and treatment. To eliminate these latencies, we clinically implemented a novel same-day...

AGuIX nanoparticles, composed of a polysiloxane core with gadolinium chelates, are a theranostic agent, providing both MRI contrast and radiosensitization. The ongoing NanoBrainMets clinical trial looks to evaluate the therapeutic efficacy of AGuIX by quantif...

To evaluate the dosimetric accuracy of plans calculated on the Varian TrueBeam HyperSight cone beam CT (CTHS) imager upgrade compared to current fan beam simulation CT (CTSim) solutions towards online adaptive radiotherapy.

Conventional dual-energy material decomposition methods suffer from significant noise amplification, which limits their clinical utility for tasks such as intra-fraction markerless tumor tracking. This study introduces PRISM, an open-source Julia framework sp...

Dual-layer imagers (DLIs) enable simultaneous acquisition of low- and high-energy images in a single exposure, offering detector-based spectral imaging capability for the on-board kV imaging systems of conventional linear accelerators towards avoiding motion...

To evaluate the correlation between lung tumor and pulmonary vessel motion under MR-guided radiotherapy and to inform surrogate tracking feature selection when direct tumor tracking is challenging.

Therapy Physics

Therapy Physics

As artificial intelligence becomes increasingly integral to clinical oncology and clinical trials, medical physicists are uniquely positioned to lead the development of the robust system architectures required to integrate AI safely and effectively. This sess...

Clinical Trials Specialty Program

Diagnostic and Interventional Radiology Physics

Spectral imaging confers several benefits such as material decomposition, increased soft tissue contrast, and metal artifact reduction. Novel methods currently under evaluation for adoption to linac onboard imaging include a kV dual-layer imager investigated...

Automatic treatment planning and physician’s plan preference quantification are both critical tasks in High-dose-rate brachytherapy (HDRBT) of cervical cancer for rapidly generating high-quality plans meeting physician’s intent. This study employs inverse dee...

Therapy Physics