keyword
MENU ▼
Read by QxMD icon Read
search

CBCT

keyword
https://www.readbyqxmd.com/read/28102960/nine-degrees-of-freedom-flexmap-for-a-cone-beam-computed-tomography-imaging-device-with-independently-movable-source-and-detector
#1
Peter Keuschnigg, Daniel Kellner, Karl Fritscher, Andrea Zechner, Ulrich Mayer, Philipp Huber, Felix Sedlmayer, Heinz Deutschmann, Philipp Steininger
PURPOSE: Couch-mounted cone-beam computed tomography (CBCT) imaging devices with independently rotatable x-ray source and flat-panel detector arms for acquisitions of arbitrary regions of interest (ROI) have recently been introduced in image-guided radiotherapy (IGRT). This work analyzes mechanical limitations and gravity-induced effects influencing the geometric accuracy of images acquired with arbitrary angular constellations of source and detector in nonisocentric trajectories, which is considered essential for IGRT...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28101784/dental-implants-and-grafting-success-remain-high-despite-large-variations-in-maxillary-sinus-mucosal-thickening
#2
Bartosz Maska, Guo-Hao Lin, Abdullah Othman, Shabnam Behdin, Suncica Travan, Erika Benavides, Yvonne Kapila
BACKGROUND: Although mucosal thickening is the most common radiographic finding observed regarding sinus pathology, the knowledge regarding its clinical significance on the outcomes of dental implants and grafting in the maxillary sinuses is still limited. We hypothesized that mucosal thickening would not alter the predictability for sinus floor augmentation and dental implant placement. The purpose of this retrospective study was to evaluate the outcomes of dental implant placement in sinus-augmented areas with preexisting sinus mucosal thickening...
December 2017: International Journal of Implant Dentistry
https://www.readbyqxmd.com/read/28097666/understanding-external-cervical-resorption-patterns-in-endodontically-treated-teeth
#3
M Mavridou, E Hauben, M Wevers, E Schepers, L Bergmans, P Lambrechts
AIM: To understand the pattern of external cervical resorption (ECR) in endodontically treated teeth. To compare characteristics and mechanisms of ECR in root filled teeth with those established in teeth with vital pulps. METHODOLOGY: Seven cases of endodontically treated permanent teeth displaying ECR were investigated. ECR diagnosis was based on clinical findings and radiographic examination with cone-beam computed tomography (CBCT). The extracted teeth were further analysed by a nano-focus computed tomographic (nano-CT) system, hard tissue histology and scanning electron microscopy (SEM)...
January 18, 2017: International Endodontic Journal
https://www.readbyqxmd.com/read/28095486/three-dimensional-assessment-of-temporomandibular-joint-using-mri-cbct-image-registration
#4
Mohammed A Q Al-Saleh, Kumaradevan Punithakumar, Manuel Lagravere, Pierre Boulanger, Jacob L Jaremko, Paul W Major
PURPOSE: To introduce a new approach to reconstruct a 3D model of the TMJ using magnetic resonance imaging (MRI) and cone-beam computed tomography (CBCT) registered images, and to evaluate the intra-examiner reproducibility values of reconstructing the 3D models of the TMJ. METHODS: MRI and CBCT images of five patients (10 TMJs) were obtained. Multiple MRIs and CBCT images were registered using a mutual information based algorithm. The articular disc, condylar head and glenoid fossa were segmented at two different occasions, at least one-week apart, by one investigator, and 3D models were reconstructed...
2017: PloS One
https://www.readbyqxmd.com/read/28094865/long-term-side-effects-on-the-temporomandibular-joints-and-orofacial-function-in-patients-with-obstructive-sleep-apnea-treated-with-a-mandibular-advancement-device
#5
Sofie W Knappe, Merete Bakke, Palle Svanholt, Arne Petersson, Liselotte Sonnesen
Patients with obstructive sleep apnea (OSA) in long-term treatment with a mandibular advancement device (MAD) to increase the upper airway space, may develop changes in the temporomandibular joint (TMJ) and the orofacial function due to the protruded jaw position during sleep. The aim was to investigate the influence of long-term MAD treatment on the TMJs, orofacial function and occlusion. This prospective study included 30 men and 13 women (median age 54) with OSA (Apnoea-Hypopnoea Index (AHI): 7-57). They were examined with the Nordic Orofacial Test Screening (NOT-S), the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and cone beam computed tomography (CBCT) of the TMJs...
January 17, 2017: Journal of Oral Rehabilitation
https://www.readbyqxmd.com/read/28086901/gpu-accelerated-voxel-driven-forward-projection-for-iterative-reconstruction-of-cone-beam-ct
#6
Yi Du, Gongyi Yu, Xincheng Xiang, Xiangang Wang
BACKGROUND: For cone-beam computed tomography (CBCT), which has been playing an important role in clinical applications, iterative reconstruction algorithms are able to provide advantageous image qualities over the classical FDK. However, the computational speed of iterative reconstruction is a notable issue for CBCT, of which the forward projection calculation is one of the most time-consuming components. METHOD AND RESULTS: In this study, the cone-beam forward projection problem using the voxel-driven model is analysed, and a GPU-based acceleration method for CBCT forward projection is proposed with the method rationale and implementation workflow detailed as well...
January 5, 2017: Biomedical Engineering Online
https://www.readbyqxmd.com/read/28079527/binary-moving-blocker-based-scatter-correction-in-cone-beam-computed-tomography-with-width-truncated-projections-proof-of-concept
#7
Ho Lee, Benjamin Fahimian, Lei Xing
This paper proposes a binary moving-blocker (BMB)-based technique for scatter correction in cone-beam computed tomography (CBCT). In concept, a beam blocker consisting of lead strips, mounted in front of the x-ray tube, moves rapidly in and out of the beam during a single gantry rotation. The projections are acquired in alternating phases of blocked and unblocked cone beams, where the blocked phase results in a stripe pattern in the width direction. To derive the scatter map from the blocked projections, one-dimensional B-Spline interpolation/extrapolation is applied by using the detected information in the shaded regions...
January 12, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28079267/estimating-4d-cbct-from-prior-information-and-extremely-limited-angle-projections-using-structural-pca-and-weighted-free-form-deformation-for-lung-radiotherapy
#8
Wendy Harris, You Zhang, Fang-Fang Yin, Lei Ren
PURPOSE: To investigate the feasibility of using structural-based principal component analysis (PCA) motion-modeling and weighted free-form deformation to estimate on-board 4D-CBCT using prior information and extremely limited angle projections for potential 4D target verification of lung radiotherapy. METHODS: A technique for lung 4D-CBCT reconstruction has been previously developed using a deformation field map (DFM)-based strategy. In the previous method, each phase of the 4D-CBCT was generated by deforming a prior CT volume...
January 12, 2017: Medical Physics
https://www.readbyqxmd.com/read/28078367/topographical-relationship-between-positions-of-lingual-foramina-and-attachment-of-mylohyoid-muscle-in-mental-region
#9
Naohiro Morikage, Tomohiro Hamada, Akinobu Usami, Satoshi Takada
PURPOSE: Lingual foramina can be observed between the lingual aspects of the mandible in humans. A sublingual artery is thought to exist in sublingual space and a submental artery in submaxillary space, which pierce the mandible through lingual foramina. During surgery for oral implant placement between apices of the mental foramen, it is important to determine the existence and positioning of lingual foramina. The purpose of this study was to investigate the positions of lingual foramina in relation to the mylohyoid muscle and vertical position of the mylohyoid line using cone-beam computed tomography (CBCT) images...
January 11, 2017: Surgical and Radiologic Anatomy: SRA
https://www.readbyqxmd.com/read/28077902/the-length-of-the-greater-palatine-canal-in-a-lebanese-population-a-radio-anatomical-study
#10
Georges Aoun, Ibrahim Nasseh
OBJECTIVE: The aim of this study was to evaluate the length of the greater palatine canal in a Lebanese population using cone-beam computed tomography (CBCT) technology. MATERIAL AND METHODS: In this study, we measured the length of 148 greater palatine canals in 74 CBCT images of Lebanese adult patients (38 females and 36 males). The data obtained was analyzed statistically to determine 1) if age is related to the length of the canal, 2) if the length of the left side tends to be systematically larger or smaller than the length of the right side, and 3) if the mean length of the canals in females is different than the one in males...
2016: Acta Informatica Medica: AIM
https://www.readbyqxmd.com/read/28074785/deformable-registration-of-ct-and-cone-beam-ct-with-local-intensity-matching
#11
Seyoun Park, William Plishker, Harry Quon, John Wong, Raj Shekhar, Junghoon Lee
Cone-beam CT (CBCT) is a widely used intra-operative imaging modality in image-guided radiotherapy and surgery. A short scan followed by a filtered-backprojection is typically used for CBCT reconstruction. While data on the mid-plane (plane of source-detector rotation) is complete, off-mid-planes undergo different information deficiency and the computed reconstructions are approximate. This causes different reconstruction artifacts at off-mid-planes depending on slice locations, and therefore impedes accurate registration between CT and CBCT...
February 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28074591/variations-in-crestal-cortical-bone-thickness-at-dental-implant-sites-in-different-regions-of-the-jawbone
#12
Yi-Chun Ko, Heng-Li Huang, Yen-Wen Shen, Jyun-Yi Cai, Lih-Jyh Fuh, Jui-Ting Hsu
BACKGROUND: Dental implants have become reliable and predictable tools for treating missing teeth. The survival rate of dental implants is markedly influenced by the host bone quality and quantity of the jawbone. A better host bone provides higher initial stability of the dental implant, resulting in better osseointegration and a higher success rate. Host bone quality and quantity are determined by the crestal cortical bone thickness and inner cancellous bone density. OBJECTIVE: The purpose of this study was to determine the crestal cortical bone thickness at dental implant sites in different regions of the jawbone through the use of dental cone-beam computed tomographic (CBCT) images...
January 10, 2017: Clinical Implant Dentistry and related Research
https://www.readbyqxmd.com/read/28073637/variable-angle-stereo-imaging-for-rapid-patient-position-correction-in-an-in-house-real-time-position-monitoring-system
#13
Sankar Arumugam, Mark Sidhom, Daniel Truant, Aitang Xing, Mark Udovitch, Lois Holloway
PURPOSE: To develop and validate a variable angle stereo image based position correction methodology in an X-ray based in-house online position monitoring system. MATERIALS AND METHODS: A stereo imaging module that enables 3D position determination and couch correction of the patient based on images acquired at any arbitrary angle and arbitrary angular separation was developed and incorporated to the in-house SeedTracker real-time position monitoring system. The accuracy of the developed system was studied by imaging an anthropomorphic phantom implanted with radiopaque markers set to known offset positions from its reference position in an Elekta linear accelerator (LA) and associated XVI imaging system...
January 7, 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28072990/-the-images-of-osteoarthrosis-associated-with-anterior-disc-displacement-without-reduction-detected-by-cone-beam-ct
#14
J H Han, J Lei, M Q Liu, K Y Fu
Objective: To analyze the radiological characteristics of the condylar bone in patients with anterior disc displacement without reduction of temporomandibular joint using cone-beam CT (CBCT), and to further investigate the clinical factors possibly associated with the early-stage osteoarthritic changes. Methods: Two hundred and four individuals (≤30 years old) diagnosed as unilateral anterior disc displacement without reduction (disease duration≤1 year) were recruited. CBCT images of bilateral condyles were independently evaluated by two assessors and documented...
January 9, 2017: Zhonghua Kou Qiang Yi Xue za Zhi, Zhonghua Kouqiang Yixue Zazhi, Chinese Journal of Stomatology
https://www.readbyqxmd.com/read/28072571/a-geometric-atlas-to-predict-lung-tumor-shrinkage-for-radiotherapy-treatment-planning
#15
Pengpeng Zhang, Andreas Rimner, Ellen Yorke, Yu-Chi Hu, Licheng Kuo, Aditya Apte, Natalie Lockney, Andrew Jackson, Gig Mageras, Joseph O Deasy
To develop a geometric atlas that can predict tumor shrinkage and guide treatment planning for non-small-cell lung cancer. To evaluate the impact of the shrinkage atlas on the ability of tumor dose escalation. The creation of a geometric atlas included twelve patients with lung cancer who underwent both planning CT and weekly CBCT for radiotherapy planning and delivery. The shrinkage pattern from the original pretreatment to the residual posttreatment tumor was modeled using a principal component analysis, and used for predicting the spatial distribution of the residual tumor...
January 10, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28072395/evaluation-of-adaptive-treatment-planning-for-patients-with-non-small-cell-lung-cancer
#16
Hualiang Zhong, Salim Siddiqui, Benjamin Movsas, Indrin Chetty
The purpose of this study was to develop metrics to evaluate uncertainties in deformable dose accumulation (DDA) for patients with non-small cell lung cancer (NSCLC). Initial treatment plans (primary) and cone-beam CT (CBCT) images were retrospectively processed for seven NSCLC patients, who showed significant tumor regression during the course of treatment. Each plan was developed with IMRT for 2 Gy��33 fractions. A B-spline-based DIR algorithm was used to register weekly CBCT images to a reference image acquired at fraction 21 and the resultant displacement vector fields (DVFs) were then modified using a finite element method (FEM)...
January 10, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28069053/influence-of-daily-imaging-on-plan-quality-and-normal-tissue-toxicity-for-prostate-cancer-radiotherapy
#17
Katharina Bell, Marina Heitfeld, Norbert Licht, Christian Rübe, Yvonne Dzierma
BACKGROUND: Modern radiotherapy offers various possibilities for image guided verification of patient positioning. Different clinically relevant IGRT (image guided radiotherapy) scenarios were considered with regard to their influence on dosimetric plan quality and normal tissue complication probability (NTCP). METHODS: This study is based on treatment plans of 50 prostate patients. We evaluate the clinically performed IGRT and simulate the influence of different daily IGRT scenarios on plan quality...
January 10, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28068573/guidelines-for-reproducing-geometrical-aspects-of-intra-oral-radiographs-images-on-cone-beam-computed-tomography
#18
Janaina Paiva Curi, Thiago Leite Beaini, Ricardo Henrique Alves da Silva, Rodolfo Francisco Haltenhoff Melani, Israel Chilvarquer, Edgard Michel Crosato
Human identification requires comparison of individual traits of a person, depending on the availability and reproduction of antemortem (AM) records. If there is no presumed identity or AM exams are not available for comparison, the production of postmortem (PM) records is impaired. The purpose of this research is to describe and test standards to enable the comparison of antemortem periapical radiographs to images extracted from the manipulation of postmortem CBCT exams in multiple identification simulations in a randomized blind study...
December 22, 2016: Forensic Science International
https://www.readbyqxmd.com/read/28066676/image-guided-localization-of-small-lung-nodules-in-video-assisted-thoracic-surgery
#19
REVIEW
Ze-Rui Zhao, Rainbow W H Lau, Peter S Y Yu, Randolph H L Wong, Calvin S H Ng
The advancement of imaging technology has recently facilitated single port minimally-invasive thoracic surgery techniques. Cone-beam computed tomography (CBCT) shows promising results in visualizing the target lesion and its surrounding critical anatomy, with an error of less than 2 mm. The integration of CBCT with the operating room (OR) to form the hybrid OR, provides unparalleled real-time imaging of the patient, which can be used with electromagnetic navigation bronchoscopy to confirm successful navigation and increase procedural accuracy particularly for small peripheral pulmonary targets...
October 2016: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/28065704/alveolar-bone-level-changes-in-maxillary-expansion-treatments-assessed-through-cbct
#20
Vi Pham, Manuel O Lagravère
OBJECTIVES: Determine changes in alveolar bone levels during expansion treatments as assessed through cone-beam computer tomography (CBCT). METHODS: Sixty-one patients from Edmonton, Canada, with maxillary transverse deficiencies were split into three groups. One group was treated with a bone-anchored expander, another group was treated with a tooth-borne maxillary expander (Hyrax) and one group was untreated. CBCTs were obtained from each patient at two time points (initialT1 and at removal of appliance after 6 months T2)...
January 5, 2017: International Orthodontics
keyword
keyword
663
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"