Purpose Radiomics provides quantitative tissue heterogeneity profiling and is an exciting approach to developing imaging biomarkers in the context of precision medicine. Normal-appearing parenchymal tissues surrounding primary tumors can harbor microscopic disease that leads increased risk distant metastasis (DM). This study assesses whether computed-tomography (CT) features such peritumoral predict DM locally advanced non-small cell lung cancer (NSCLC). Material methods 200 NSCLC patients...

Purpose: To determine the validity of assumption that γ dose distribution comparison tool defaults to distance agreement test under conditions clinically relevant steep gradients and criteria. Methods: The was tested by computing angle θ between axis vector for clinical treatment plans. a function evaluated gradient ratio (α) difference (DTA) Dose distributions from prostate, head neck, lung plans were examined: 50 selected each prostate neck sites 27 lung. Dose‐gradient histograms prepared...

To demonstrate that a "5DCT" technique which utilizes fast helical acquisition yields the same respiratory-gated images as commercial for regular, mechanically produced breathing cycles.Respiratory-gated of an anesthetized, ventilated pig were generated using Siemens low-pitch protocol and 5DCT range rates amplitudes with standard low dose imaging protocols. reconstructions independently evaluated by measuring distances between tissue positions predicted 5D motion model those measured...

Purpose: To determine if and by how much the commercial 4DCT protocols under‐ overestimate tumor breathing motion. Methods: 1D simulations were conducted that modeled a 16‐slice CT scanner tumors moving proportionally to amplitude. External surrogate traces of at least 5‐min duration for 50 patients used. Breathing trace amplitudes converted motion relating nominal 90th percentile amplitude, reflecting defined more recent 5DCT approach. Based on clinical low‐pitch helical acquisition,...

Breathing motion modeling requires observation of tissues at sufficiently distinct respiratory states for proper 4D characterization. This work proposes a method to improve sampling the breathing cycle with limited imaging dose. We designed and tested prospective free-breathing acquisition protocol simulation using datasets from five patients imaged model-based 4DCT technique. Each dataset contained 25 fast helical CT scans simultaneous surrogate measurements. Tissue displacements were...

Radiotherapy is safely employed for treating wide variety of cancers. The radiotherapy workflow includes a precise positioning the patient in intended treatment position. While trained radiation therapists conduct positioning, consultation occasionally required from other experts, including oncologist, dosimetrist, or medical physicist. In many circumstances, rural clinics and developing countries, this expertise not immediately available, so concerns may get addressed. paper, we present...

The article aims to determine if a prospective acquisition algorithm can be used find the ideal set of free-breathing phases for fast-helical model-based 4D-CT. A retrospective five-patient dataset that consisted 25 repeated free breathing CT scans per patient was used. sum square root amplitude difference between all defined as an objective function optimality sets phases. intended specific would yield motion model could accurately predict in scans. Voxel models were calculated using...

Deformable image registration (DIR) is an important step in radiotherapy treatment planning. An optimal input parameter set critical to achieve the best performance with specific algorithm. <i>Methods </i> In this paper, we investigated a optimization strategy for Optical-flow based DIR of 4DCT lung anatomy. A novel fast simulated annealing adaptive Monte Carlo sampling algorithm (FSA-AMC) was solving complex non-convex problem. The metric error given computed using landmark-based mean...

A recently proposed "5DCT" protocol uses deformable registration of free-breathing fast-helical CT scans to generate a breathing motion model. In order allow accurate registration, images are required be free doubling-artefacts, which arise when tissue is greater than scan speed.Using unique set digital phantoms based on patient data and verified with phantom, this work identifies the minimum scanner parameters successfully artefact-free scans. phantom 5 patients were imaged 25 times under...

Purpose: To investigate the applicability of feasibility‐seeking cyclic orthogonal projections to field intensity modulated proton therapy (IMPT) inverse planning. Feasibility constraints only, as opposed optimization a merit function, is less demanding algorithmically and holds promise parallel computations capability with non‐cyclic algorithms such string‐averaging or block‐iterative strategies. Methods: A virtual 2D geometry was designed containing C‐shaped planning target volume (PTV)...

Abstract Disclosure: R. Wang: None. T. Dou: L. Guan: X. Qi: C. Yu: Q. Premature ovarian failure (POF), a condition impacting women's fertility and physical well-being. Specifically, autoimmune thyroid disease (TAI) is recognized as an organ-specific that may co-occur with POF in clinical scenarios, yet the precise nature of their relationship remains uncertain. The objective this study to investigate influence TAI on function, identify shared pathogenic genes, predict potentially effective...

To determine if the parameters relating lung tissue displacement to a breathing surrogate signal in previously published respiratory motion model vary with rate of during image acquisition. An anesthetized pig was imaged using multiple fast helical scans sample cycle simultaneous monitoring. Three datasets were collected while animal mechanically ventilated different rates: 12 bpm (breaths per minute), 17 bpm, and 24 bpm. sets describing correspondences between signals displacements...

Purpose: To develop tools for performing 4D proton computed tomography (CT). Methods: A suitable patient with a tumor in the right lower lobe was selected from set of CT scans. The volumetric images formed basis calculating parameters breathing model that allows reconstruction static reference and each phase. were imported into TOPAS Monte Carlo simulation platform simulating an experimental scan 45 projections spaced by 4 degree intervals. Each projection acquired data 2 seconds followed...

Purpose: To perform a parametric study of the effect registration parameters on 4D‐CT image accuracy.Methods and Materials: A GPU based that registers 4D lung anatomy using multi‐level multi‐contrast optical flow was used for this study. set 14 datasets employed The segmented into surface contour, blood vessels parenchyma regions OsiriX. started at lowest resolution 3D volume. Within each level, volumes were registered flow. motion field first computed contour pairs in resolution. At stage,...

The aim of this paper is to enable model guided multi-scale and multi-modal image integration for the head neck anatomy. modality used purpose includes multi-pose Magnetic Resonance Imaging (MRI), Mega Voltage CT, hand-held Optical Coherence Tomography. A biomechanical that incorporates subject-specific young's modulus shear properties developed from MRI, positioned in treatment setup using CT (MVCT), actuated multiple kinect surface cameras mimic patient postures during Microscopy (OCM)...

Purpose: To develop a technique that validates breathing motion model and its reconstructed phase-specific image generation process using the original free-breathing images as ground truths. Methods: 16 lung cancer patients underwent published protocol where 25 fast helical CT scans were acquired with simultaneous surrogate. The first was arbitrarily selected reference image. For constructing patient-specific model, state-of-the-art deformable registration employed to determine tissue...

Purpose: Fusing information from multiple correlated realizations (e.g., 4DCT) can improve image quality. This process often involves ill‐conditioned and asymmetric nonlinear registration the proper selection of a reference is important. work proposes to examine post‐registration variation indirectly for such selection, develops further insights reduce number cross‐registrations needed. Methods: We consider each individual scan as noisy point in vicinity an manifold, related by motion....

Purpose: A recently proposed 5DCT protocol uses fast helical CT scans to model lung tissue motion that requires one of the be used as a reference for deformable image registration. We have found that, while are acquired using acquisition, residual motionartifacts remain during mid inspiration or exhalation. Selecting scan with minimal artifacts will improve registration and accuracy. Methods: free‐breathing patient was scanned 25 successive times in alternating directions Siemens 64‐slice...