Background: Artifacts fault image quality but handling several factors can affect it. This study was conducted to investigate the effect of object size on artifacts in cone-beam computed tomography systems.
Methods: Five phantoms, each containing a titanium implant in a sheep bone block, were fabricated of various sizes ranging from XS to XL: The M phantom was the same size as the device's field of view (FOV). The L and XL phantoms were 20 and 40% larger than the FOV while the S and XS phantoms were 20 and 40% smaller than FOV, respectively. Ballistic gelatin was used to fill the phantoms. Phantoms were scanned by NewTom VGI and HDXWill Q-FACE. The mean and standard deviation (SD) of gray values in each 120 ROI was obtained by OnDemand software. The contrast to noise ratio (CNR) was also calculated.
Results: The gray value in S and M phantoms were more homogenous. The lowest SD value (10.20) was found in S phantom. The highest value for SD (125.16) was observed in XL phantom. The lowest (4.47) and highest (9.92) CNR were obtained in XL and S phantoms, respectively. HDXWill Q-FACE recorded a higher SD and a lower CNR than NewTom VGI (P < 0.05).
Conclusion: Object dimensions of the FOV size or up to 20% smaller provided better image quality. Since the dimensions of soft tissue in most patients are larger than the selective FOV, it is recommended that in CBCT artifacts studies, an object with dimensions closer to the patient's dimensions be used to better relate the results with the clinical condition, because the sample dimensions affect the amount of artifacts.
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http://dx.doi.org/10.1186/s13005-022-00326-1 | DOI Listing |
Cancer Imaging
December 2024
Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, People's Republic of China.
Purpose: To assess and compare the diagnostic efficiency of histogram analysis of monochromatic and iodine images derived from spectral CT in predicting Ki-67 expression in gastric gastrointestinal stromal tumors (gGIST).
Methods: Sixty-five patients with gGIST who underwent spectral CT were divided into a low-level Ki-67 expression group (LEG, Ki-67 < 10%, n = 33) and a high-level Ki-67 expression group (HEG, Ki-67 ≥ 10%, n = 32). Conventional CT features were extracted and compared.
Respir Res
December 2024
National Jewish Health, Denver, USA.
Background: We sought consensus among practising respiratory physicians on the prediction, identification and monitoring of progression in patients with fibrosing interstitial lung disease (ILD) using a modified Delphi process.
Methods: Following a literature review, statements on the prediction, identification and monitoring of progression of ILD were developed by a panel of physicians with specialist expertise. Practising respiratory physicians were sent a survey asking them to indicate their level of agreement with these statements on a binary scale or 7-point Likert scale (- 3 to 3), or to select answers from a list.
BMC Oral Health
December 2024
College of Dental Medicine, QU Health, Qatar University, P.O. Box: 2713, Doha, Qatar.
Background: The collum angle, tooth dimensions, root length, and alveolar bone thickness have a significant impact on orthodontic diagnosis and treatment planning. The boundaries of orthodontic tooth movement are determined by alveolar bone thickness and dimensions while the collum angle determines the appropriate positioning of the root relative to the cortical plate. This study aimed to compare the collum angle, crown dimensions, root length, and alveolar bone thickness of the upper and lower incisors, canines, and premolars in subjects with varying anteroposterior relationships.
View Article and Find Full Text PDFJ Orthop Surg Res
December 2024
Department of Orthopedics and Trauma, Peking University People's Hospital, Beijing, China.
Background: The traditional classification for lateral malleolus fracture has its limitations. In this study, we introduced a three-dimensional (3D) fracture mapping technique using computed tomography (CT) data to assess fracture line distributions and their impact on patient outcomes, offering a refined classification approach.
Methods: Retrospectively, we analysed 97 patients who underwent lateral malleolus fracture surgeries (2014-2019), using CT Digital Imaging and Communications in Medicine data to create 3D models and fracture maps.
BMC Oral Health
December 2024
Department of Orthodontics, Central Laboratory, Hospital for Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices & Beijing Key Laboratory of Digital Stomatology & Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health & NMPA Key Laboratory for Dental Materials & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Peking University School, 22th Zhongguancun South Ave, Beijing, 100081, China.
Background: Orthodontic tooth movement (OTM) relies on the remodeling of periodontal tissues, including the periodontal ligament (PDL) and alveolar bone. Collagen remodeling plays a crucial role during this process, allowing for the necessary changes in the PDL's structure and function. Endo180, an urokinase plasminogen activator receptor-associated protein, is a transmembrane receptor regulated collagen remodeling.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!