Search results for "tomography"
showing 10 items of 2332 documents
Three-year follow-up of patients at intermediate probability of coronary artery disease assessed with Multislice Computed Tomography Coronary Angiogr…
2011
Purpose Methods and Materials Results Conclusion References Personal Information
Optimal recovery of a radiating source with multiple frequencies along one line
2020
We study an inverse problem where an unknown radiating source is observed with collimated detectors along a single line and the medium has a known attenuation. The research is motivated by applications in SPECT and beam hardening. If measurements are carried out with frequencies ranging in an open set, we show that the source density is uniquely determined by these measurements up to averaging over levelsets of the integrated attenuation. This leads to a generalized Laplace transform. We also discuss some numerical approaches and demonstrate the results with several examples.
Algorithms for the Automated Analysis of Age-Related Macular Degeneration Biomarkers on Optical Coherence Tomography: A Systematic Review
2017
PURPOSE To assess the quality of optical coherence tomography (OCT) grading algorithms for retinal biomarkers of age-related macular degeneration (AMD). METHODS Following a systematic review of the literature data on detection and quantification of AMD retinal biomarkers by available algorithms were extracted and descriptively synthesized. Algorithm quality was assessed using a modified version of the Quality Assessment of Diagnostic Accuracy Studies 2 checklist with a focus on accuracy against established reference standards and risk of bias. RESULTS Thirty five studies reporting computer-aided diagnosis (CAD) tools for qualitative analysis or algorithms for quantitative analysis were iden…
PET Studies of d-Methamphetamine Pharmacokinetics in Primates: Comparison with l-Methamphetamine and (—)-Cocaine
2007
The methamphetamine molecule has a chiral center and exists as 2 enantiomers, d-methamphetamine (the more active enantiomer) and l-methamphetamine (the less active enantiomer). d-Methamphetamine is associated with more intense stimulant effects and higher abuse liability. The objective of this study was to measure the pharmacokinetics of d-methamphetamine for comparison with both l-methamphetamine and (-)-cocaine in the baboon brain and peripheral organs and to assess the saturability and pharmacologic specificity of binding.d- and l-methamphetamine and (-)-cocaine were labeled with (11)C via alkylation of the norprecursors with (11)C-methyl iodide using literature methods. Six different ba…
Significance of immunohistochemistry biomarkers in prediction of malignant transformation of oral lichen planus
2022
Background: Oral lichen planus (OLP) is a chronic inflammatory disorder with increased risk for malignant transformation. Biomarker validation is a pivotal step in moving newly discovered biomarkers towards clinical implementation. We performed a systematic review of studies on biomarkers related to OLP, wherein biomarkers have been described in at least two independent studies. Our aim was to determine whether any of these biomark-ers might be promising in predicting the increased risk of malignant transformation of OLP. Material and Methods: We searched the following databases until August 2021: PUBMED, EMBASE, and Web of Science. Due to high heterogeneity, a qualitative rather than quant…
Aqueous foam as the carrier phase in the deposition of fibre networks
2015
Re-exposure in cone beam CT of the dentomaxillofacial region: a retrospective study.
2018
Cone beam CT (CBCT) often uses a smaller field of view compared to conventional CT scans. This might lead to a wrong field of view with the need for secondary exposure (“retakes”). The purpose of this retrospective study was to assess the frequency of re-exposures in CBCT and to identify whether the parameters age, gender, and field of view have an influence on the re-exposure of the patient. Additionally, the causes of re-exposures were determined and categorized. METHODS: In a retrospective cohort study CBCT images of 4986 patients from the patient database from the Department of Oral Radiology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany were included a…
Maxillary first molar with three mesiobuccal canals confirmed with spiral computer tomography
2012
Anatomic variations in root canal morphology have become easier to detect with the rapid advancements in clinical and diagnostic aids. Also an increased awareness of unusual anatomic morphology and a better understanding of the root canal system guides the clinician in diagnosis and treatment of such variations in order to achieve a successful endodontic outcome. Mesiobuccal root of first maxillary molar teeth have been considered to be one of the most complex and challenging root canal systems. This case report presents a successful management of a third canal in the mesiobuccal root of permanent maxillary first molar using dental operating microscope along with a modified access preparati…
3D-CT von Frakturen: Vergleich von Volumen- und Oberflächen-Rekonstruktionen
1998
Purpose The comparison of volume rendering (VR) and surface rendering (SSD) for demonstrating fractures from spiral-CT data. Materials and methods Standardized VR and SSD projections were produced from 50 spiral CT scans of 50 consecutive patients with fractures. Appropriate multiplanar reformattings (MPR) were used as the standard. Results SSD provided sufficient information in 31/50 cases. Results of VR were not significantly different (33/50). VR was superior in demonstrating 6/7 craniofacial fractures and 3/3 calcaneal fractures. SSD was superior for visualizing 2/3 shoulder fractures and 2/2 elbow fractures. Conclusion VR is a flexible technique for the depiction of fractures and the a…
Importance of cone beam computed tomography for diagnosis of calcifying cystic odontogenic tumour associated to odontoma. Report of a case.
2010
Made available in DSpace on 2013-08-12T18:45:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-01 Made available in DSpace on 2013-09-30T19:14:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:31:24Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T15:31:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-01 The calcifying cystic odontogenic tumour (CCOT) is a rare benign cystic neoplasm not infrequently associated with odontoma. This report documents a case of CCOT associated with compound odontoma arising in the anterior maxilla in a 25-year-old woman. Co…