Purpose: Understanding motion characteristics of liver such as, interfractional and intrafractional variability, difference in within different locations the organ, their complex relationship with breathing cycles are particularly important for image‐guided SBRT. The purpose this study was to investigate based on fiducial markers tracked x‐ray projections CBCT scans, taken immediately prior treatments. Methods: Twenty SBRT patients were analyzed. Each patient had three (2 × 5‐mm gold)...

Purpose: All forms of past and current high‐dose‐rate brachytherapy utilize immobile applicators during treatment delivery. The only moving part is the source itself. This paradigm misses an important degree freedom that, if explored, can in some instances produce previously unachievable dose conformality; that is, dynamic motion applicator itself Monte Carlo planning simulations were used to illustrate potential benefits for rectal cancer applications particular. concept termed modulated...

Background/Objectives: Cone-beam computed tomography (CBCT)-guided online adaptive radiotherapy (oART) represents a significant advancement in radiation oncology, enabling on-couch plan adaptation to account for daily anatomical changes. While this automation improves precision and workflow efficiency, it also introduces new failure modes (FMs) irregularities. This study aimed systematically evaluate the clinical technical challenges associated with CBCT-guided oART implementation. Methods:...

CBCT-guided online adaptive radiotherapy (oART) plans presently utilize daily synthetic CTs (sCT) that are automatically generated using deformable registration algorithms. These algorithms may have poor performance at reproducing variable volumes of gas present during treatment. Therefore, we analyzed the air mapping error between CBCTs and corresponding sCT explored its dosimetric effect on oART plan calculation.Abdominopelvic volume was contoured both CBCT images for 207 pelvic...

Purpose: The aim of this work was to design a novel high‐dose rate (HDR) ( 192 Ir) brachytherapy applicator for treatment rectal carcinomas that uses tungsten shielding possibly improved dosimetric results over commercial applicator(s). Methods: A set 15 single‐depth applicators and one dual‐depth were designed simulated using Monte Carlo (MCNPX). All high‐density alloy cylinders, 16‐mm in diameter, 60‐mm long, with longitudinal grooves within which an Ir source can be placed. designs varied...

Abstract Purpose CBCT‐guided online‐adaptive radiotherapy (oART) systems have been made possible by using artificial intelligence and automation to substantially reduce treatment planning time during on‐couch adaptive sessions. Evaluating plans generated an session presents significant challenges the clinical team as process gets compressed into a shorter window than offline planning. We identified MU variations up 30% difference between plan reference in several oART sessions that caused...

Purpose To evaluate respiratory motion of a patient by generating four-dimensional digital tomosynthesis (4D DTS), extracting signal from patients' on-board projection data, and ensuring the feasibility 4D DTS as localization tool for targets which have movement. Methods Materials Four patients with lung liver cancer were included to verify 4D-DTS an imager. CBCT acquisition (650–670 projections) was used reconstruct images breath generated diaphragm during data acquisition. Based on...

Abstract Various reactions, intentional or unwanted, between several types of boron‐containing compound and multifunctional nucleophilic substrates occurring on the probe tip can be examined in situ by negative‐ion fast atom bombardment mass spectrometry (FABMS). Unwanted reactions spiroborates with common liquid matrices avoided using tetraethylene glycol diethyl ether as solvent for FABMS. Even so, components mixtures undergo ligand exchange each other. Different orientations hydroxy...

Abstract Purpose To propose guidelines for lung stereotactic body radiation therapy (SBRT) when using Acuros XB (AXB) equivalent to the existing ones developed convolution algorithms such as analytic anisotropic algorithm (AAA), considering difference between algorithms. Methods A retrospective analysis was performed on 30 patients previously treated with SBRT. The original AAA plans, which were dynamic conformal arcs, recalculated and then renormalized planning target volume (PTV) coverage...

Purpose: To build, from grounds up, a novel dynamic modulated brachytherapy (DMBT) system for treating intracavitary tumors, such as rectal, breast, and vaginal cancers. The key component of the innovation is in enabling “dynamic” modulation (i.e., Ir-192 source highly collimated dynamically moved during delivery) to create an unparalleled dose conformality compared with currently available commercial systems/applicators. We show that our proposed prototype (both soft- hard-ware) extremely...

Purpose: To develop a novel brachytherapy applicator for HDR‐based accelerated partial breast irradiation (APBI) that significantly improves upon those commercially available, thereby reducing acute and late side effects seen with current APBI techniques. Methods: First, the limitations of adjusting channel placements or placing more channels in balloon‐like multi‐catheter ABPI device were explored. Then, tungsten‐shielded design was evaluated. The consists 9‐mm diameter tungsten rod,...

Purpose: This case report discusses the safe delivery of total body irradiation (TBI) to a patient with left ventricular assist device (LVAD).This treatment required radiation-dose determinations and consequential reductions for heart, LVAD, an external controller connected LVAD.Methods: The was treated using traditional 16MV anterior posterior (AP)/posterior (PA) technique at source surface distance (SSD) 515cm 400cGy in two fractions.A 3cm thick Cerrobend block placed on spoiler reduce...

Key Clinical Message A patient presented with cardiogenic shock, requiring the implantation of a left ventricular assist device (LVAD), and acute myeloblastic leukemia. This necessitated total body irradiation (TBI) while balancing dose reduction to LVAD components avoid potential radiation damage. Here we outline our treatment approach estimates LVAD. Abstract case report discusses delivery TBI an required radiation‐dose determinations consequential reductions for heart, LVAD, external...

This case report addresses the complex management of a patient with concurrent prostate cancer, inflammatory bowel disease (IBD), and bilateral total hip arthroplasty, demonstrates efficacy cone-beam computed tomography (CBCT)-guided daily online adaptive radiation therapy (oART) advanced imaging techniques in overcoming significant treatment challenges. A 68-year-old male history ulcerative colitis prostheses was diagnosed high-risk cancer. Conventional modalities, including external beam...

Abstract Purpose To compare the effect of two linacs designs on fetal dose sparing a pregnant patient, including estimation dose, and lead apron. Methods A patient with high‐grade sarcoma located in right knee/lower thigh was prescribed 51 Gy (1.7 Gy/Fx) simultaneous‐integrated‐boost (SIB) 60 to smaller volume, starting 26th gestational week. Volumetric modulated radiation therapy (VMAT) plans 6MV‐FFF were developed using identical dosimetric constraints Varian Truebeam Edge HD‐MLC Halcyon...

Purpose: Correct centering of the HDR source with spherical MammoSite balloon is critical for proper brachytherapy delivery. We tested a modified to incorporate linear MOSFET dosimeter array assess whether real‐time dosimetry measurements could confirm in catheters. Method and Materials: A “MammoSite MOSFETs” was simulated using (Thomson Nielsen) consisting 2 MOSFETs at end flexible strip spaced 4 cm apart. The placed along an uninflated 6‐French endobronchial catheter within...

Purpose: To investigate the hardware necessary for implementing our Dynamic Modulated Brachytherapy (DMBT) treatment concept rectal cancer. Methods: The DMBT robot has three major parts: 1) shield and delivery module, 2) controlling 3) monitoring software. is a tungsten alloy cylinder (r=0.95cm, l=4.5cm) with 5.5mm rectangular‐shaped opening. controlled by an aluminum pipe gear set (1:3) linear actuator (2mm/turn). An Ir‐192 radiation source will be placed through pipe. power Nema‐17...

Purpose: To develop a 3D quality assurance (QA) tool for Cyberknife plans using GPU‐based Monte Carlo dose calculation package, gDPM. The developed QA will be used as secondary check treatment planning software (TPS) reported distributions. Methods: Phase space files of the 5, 7.5, 10, 15, and 60 mm iris cones were downloaded from IAEA phase‐space database. From 60mm cone phase file, we able to generate raw all other particle rejection method. particles in binned with respect radial position...