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Showing 1 to 14 of 14 for “"Hounsfield Units"”.
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Significancer of Osteoporosis in Facial Bone Density using the Computed Tomography Scan
… was analyzed in the region of interest, and the Hounsfield units were measured. There was a significant difference in the mean bone density of the mid-facial bones between the osteoporosis group and the control group (p=0.000). For both groups, each of comparison of the 7 skeletal regions was …
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The Development and Implementation of An Anthropomorphic Head Phantom For The Assessment of Proton Therapy Treatment Procedures
… of ±3%. The relative stopping power (RSP) and Hounsfield Units (HU) were measured for potential phantom materials and a human skull was cast in tissue-equivalent Alderson material (RLSP 1.00, HU 16) with anatomical airways and a cylindrical hole for imaging and dosimetry inserts drilled into …
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Assessment of Human Alveolar Bone Density by Using Volumetric CT Machine
… for density evaluations. Bone density in Hounsfield units (HU) was assessed in a standardized implant area superimposed on the images, and also subjectively evaluated by 2 independent examiners using the Lekholm & Zarb (1985) classification. Density measurements in HU in most of the areas, …
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A Novel Artificial Intelligence-Driven Technique for Enhancing Medical Imaging Technologies to Aid Diagnosis of Non-Small Cell Lung Cancer
… features analysed by the model is that of the Hounsfield Units (HU) of each pixel within the lung, which are used to pinpoint areas of high density within the lungs that are identified as potential tumours. The model achieved a classification accuracy of 97.1% and an Area Under the Receiver …
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Discrete spring–mass system inversion of lung stiffness from 4DCT with adjoint regularization and graph convolutional network
… (GCN) as a learned prior. Per tetrahedron Hounsfield units are first mapped to a physiology guided baseline stiffness via a piecewise linear HU to modulus relation. A tetrahedral GCN operating on face adjacency then predicts small log space corrections to this baseline. Its parameters are …
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Optimizing Kilovoltage Cone-Beam Computed Tomography for Image-Guided Radiation Therapy
… dose, poor soft-tissue contrast and inaccurate Hounsfield Units as a result of in-patient scatter. The specific aims of this dissertation research are to: 1) reduce noise associated with the low-dose CBCT scans acquired with low tube current/time (mAs) protocols by the application of innovative …
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Identification of Intracranial Lesions With Dual-Energy Computed to mography and Magnetic Resonance Phase Imaging
… lesions with an attenuation greater than 100 Hounsfield Units (HU) can be definitively diagnosed as calcification. However, low-density calcifications and hemorrhage may have overlapping attenuation ranges between 40 and 100 HU and, therefore, cannot be differentiated with SECT alone. On …
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Implementation of An Anthropomorphic Phantom For The Evaluation of Proton Therapy Treatment Procedures
… (SP) of each phantom material was measured. Hounsfield Units (HU) for each phantom material were measured with a CT scanner and compared to the relative stopping power calibration curve. The tissue equivalency for each material was calculated. Two proton treatment plans were created; one …
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Modification and Implementation of The Rpc Heterogeneous Thorax Phantom For Verification of Proton Therapy Treatment Procedures
… within 5%/3mm with a reproducibility of 5%. The Hounsfield Units (HU) for lung equivalent materials (balsa wood and cork) was measured using a CT scanner. The relative linear stopping power (RLSP) of these materials was measured. The linear energy transfer (LET) of Gafchromic EBT2 film was …
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Effects on Initial Fixation of Cementless Tibial Trays in Total Knee Arthroplasty
… elements (Hypermesh, Altair, Troy, MI) and Hounsfield units for each element were extracted from the DICOM using custom Matlab scripting and converted to bone mineral density using the known densities of the phantom. The ratio of tray coverage, the tibial plateau area of the tray within the …
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Development and Implementation of A Homogeneous and A Heterogeneous Anthropomorphic End to End Quality Assurance Audit System Phantom For Magnetic Resonance Guided Radiotherapy Modalities Ranging From 0.35 T to 1.50 T
… Materials were characterized by: 1) measuring Hounsfield units, 2) visualizing in MR and CT imagers and 3) evaluating their dosimetric characteristics. Once materials were selected for the MRgRT phantoms, radiochromic film and double-loaded TLDs were then characterized in a 1.5T and a 0.35T MR …
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Computed tomography of the thorax and abdomen of the clinically normal common marmoset (Callithrix jacchus)
… 2) to describe the normal reference range of Hounsfield units (HU) of major abdominal and thoracic organs; 3) to refine the computed tomography (CT) protocol; 4) to compare abdominal CT to other imaging modalities such as radiography and ultrasound (US). Eight clinically healthy mature common …
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Understanding mechanical environment changes and biological responses to canine retraction using T-loop
… bone mineral density (BMD) represented by the Hounsfield units (HU) change were recorded and analyzed. The ME in terms of stress were also calculated by using FEM. Paired t-test and mixed model ANOVA methods were used to analyze the relationships between the mechanical inputs (quantified and …
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Imaging of abdominal aortic aneurysm disease activity and implications for endovascular aneurysm repair
… in asymptomatic patients (-81.4±7 versus -75.4±8 Hounsfield units, HU) and comparable segments in control subjects (-83.3±9 versus -78.8±6 HU, p>0.05 for all comparisons). However, symptomatic patients demonstrated higher periaortic adipose tissue attenuation in both aneurysmal (-57.9±7 HU, …