Background: Prior to selective internal radiotherapy of liver tumors, a determination of the lung shunt fraction (LSF) is performed using 99mTc- macroaggregated albumin (99mTc-MAA) injected into the hepatic artery. Most commonly planar but sometimes SPECT/CT images are acquired upon which regions of interests are drawn manually to define the liver and the lung. The LSF is then calculated by taking the count ratios between these two organs.
View Article and Find Full Text PDFBackground: The small molecule radiotracer I-PU-H71 is an imaging biomarker of epichaperome formation. The tracer has been established to localize in tissues under chronic stress, specifically in cancer cells and neurodegenerative brain cells. A first-in-human imaging trial using positron emission tomography (PET) in cancer patients revealed unexpected tracer accumulation in the myocardium.
View Article and Find Full Text PDFObjective: In frontal crashes belt-positioning boosters (BPB) may prevent submarining when the seatback is reclined. It is unclear if the BPB can also mitigate injuries in far-side lateral-oblique crashes in reclined conditions, where current restraints are less effective in reducing lateral excursion. This study aimed to understand reclined child injury risk during lateral-oblique impacts, with and without a booster seat, by using the Large Omni-Directional Child (LODC) test device.
View Article and Find Full Text PDFImportance: Given high rates of locoregional control after definitive management of head and neck squamous cell carcinoma (HNSCC), better methods are needed to project distant metastasis (DM) risk. Tumor hypoxia on 18F-fluoromisonidazole (FMISO) positron emission tomography (PET) is associated with locoregional failure, but data demonstrating an association with DM are limited.
Objective: To determine whether tumor hypoxia on FMISO PET is associated with DM risk after chemoradiotherapy (CRT) for HNSCC.
Tumor hypoxia, an integral biomarker to guide radiotherapy, can be imaged with F-fluoromisonidazole (F-FMISO) hypoxia PET. One major obstacle to its broader application is the lack of standardized interpretation criteria. We sought to develop and validate practical interpretation criteria and a dedicated training protocol for nuclear medicine physicians to interpret F-FMISO hypoxia PET.
View Article and Find Full Text PDFTHOR-AV 5F, a modified THOR-5F dummy, was designed to represent both upright and reclined occupants in vehicle crashworthiness studies. The dummy was evaluated in four test conditions: a) 25° seatback, 15 km/h, b) 25° seatback, 32 km/h, c) 45° seatback, 15 km/h, d) 45° seatback, 32 km/h. The dummy's biomechanical responses were compared against those of postmortem human subjects (PMHS) tested in the same test conditions.
View Article and Find Full Text PDFLung adenocarcinoma (ADC) is the most common non-small cell lung cancer. Surgical resection is the primary treatment for early-stage lung ADC while lung-sparing surgery is an alternative for non-aggressive cases. Identifying histopathologic subtypes before surgery helps determine the optimal surgical approach.
View Article and Find Full Text PDFThe American population is getting heavier and automated vehicles will accommodate unconventional postures. While studies replicating mid-size and upright fore-aft seated occupants are numerous, experiments with post-mortem human subjects (PMHS) with obese and reclined occupants are sparse. The objective of this study was to compare the kinematics of the head-neck, torso and pelvis, and document injuries and injury patterns in frontal impacts.
View Article and Find Full Text PDFA single-institution prospective pilot clinical trial was performed to demonstrate the feasibility of combining [Lu]Lu-PSMA-617 radiopharmaceutical therapy (RPT) with stereotactic body radiotherapy (SBRT) for the treatment of oligometastatic castration-sensitive prostate cancer. Six patients with 9 prostate-specific membrane antigen (PSMA)-positive oligometastases received 2 cycles of [Lu]Lu-PSMA-617 RPT followed by SBRT. After the first intravenous infusion of [Lu]Lu-PSMA-617 (7.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
November 2023
Purpose: To determine the mechanisms involved in partial volume radiation therapy (RT)-induced tumor response.
Methods And Materials: We investigated 67NR murine orthotopic breast tumors in Balb/c mice and Lewis lung carcinoma (LLC cells; WT, Crispr/Cas9 Sting KO, and Atm KO) injected in the flank of C57Bl/6, cGAS, or STING KO mice. RT was delivered to 50% or 100% of the tumor volume using a 2 × 2 cm collimator on a microirradiator allowing precise irradiation.
Purpose: To evaluate the yttrium-90 (Y) activity distribution in biopsy tissue samples of the treated liver to quantify the dose with higher spatial resolution than positron emission tomography (PET) for accurate investigation of correlations with microscopic biological effects and to evaluate the radiation safety of this procedure.
Materials And Methods: Eighty-six core biopsy specimens were obtained from 18 colorectal liver metastases (CLMs) immediately after Y transarterial radioembolization (TARE) with either resin or glass microspheres using real-time Y PET/CT guidance in 17 patients. A high-resolution micro-computed tomography (micro-CT) scanner was used to image the microspheres in part of the specimens and allow quantification of Y activity directly or by calibrating autoradiography (ARG) images.
Pelvis and lumbar spine fractures occur in falls, motor vehicle crashes, and military combat events. They are attributed to vertical impact from the pelvis to the spine. Although whole-body cadavers were exposed to this vector and injuries were reported, spinal loads were not determined.
View Article and Find Full Text PDFPurpose: Intraventricular compartmental radioimmunotherapy (cRIT) with 131-I-omburtamab is a potential therapy for recurrent primary brain tumors that can seed the thecal space. These patients often previously received external beam radiotherapy (EBRT) to a portion or full craniospinal axis (CSI) as part of upfront therapy. Little is known regarding outcomes after re-irradiation as part of multimodality therapy including cRIT.
View Article and Find Full Text PDFRadiolabeled antibody treatment with I-omburtamab, administered intraventricularly into the cerebrospinal fluid (CSF) space, can deliver therapeutic absorbed doses to sites of leptomeningeal disease. Assessment of distribution and radiation dosimetry is a key element in optimizing such treatments. Using a theranostic approach, we performed pretreatment I-omburtamab imaging and dosimetric analysis in patients before therapy.
View Article and Find Full Text PDFObjective: The objective of the study was to investigate the difference between elderly and young occupant injury risks using human body finite element modeling in frontal impacts.
Methods: Two elderly male occupant models (representative age 70-80 years) were developed using the Global Human Body Consortium (GHBMC) 50th percentile as the baseline model. In the first elderly model (EM-1), material property changes were incorporated, and in the second elderly model (EM-2), material and anthropometric changes were incorporated.
Background: The prognosis for metastatic and recurrent tumors of the central nervous system (CNS) remains dismal, and the need for newer therapeutic targets and modalities is critical. The cell surface glycoprotein B7H3 is expressed on a range of solid tumors with a restricted expression on normal tissues. We hypothesized that compartmental radioimmunotherapy (cRIT) with the anti-B7H3 murine monoclonal antibody omburtamab injected intraventricularly could safely target CNS malignancies.
View Article and Find Full Text PDFPrevious full body cadaver testing has shown that both obliquely oriented seats in survivable aircraft crashes and far-side oblique crashes in vehicles present distinctive occupant kinematics that are not yet well understood. Knowledge surrounding how these loading scenarios affect the lumbar spine is particularly lacking as there exists minimal research concerning oblique loading. The current study was created to evaluate a novel experimental method through comparison with existing literature, and to examine the impact of a static bending pre-load (posture) on the load-displacement response for the whole lumbar spine loaded in non-destructive axial distraction.
View Article and Find Full Text PDFBackground: An open-source, extensible medical viewing platform is described, called the TriDFusion image viewer (3DF). The 3DF addresses many broad unmet needs in nuclear medicine research; it provides a viewer with several tools not available in commercial nuclear medicine workstations, yet invaluable for imaging in research studies.
Results: The 3DF includes an image integration platform to register images from multiple imaging modalities together with delineated volumes of interest (VOIs), structures and dose distributions.
The objective of the current study was to compare the GHBMC female model responses with in-house sled test data for three small female post mortem human surrogates (PMHS) at 32 km/h and a seatback recline angle of 45 degrees. The kinematics and the seatbelt forces were used to compare the female PMHS and model responses. The study aimed to identify updates that may be needed to the model.
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