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Ribeiro, Nuno João Peixoto. "CBCT em endodontia." Master's thesis, [s.n.], 2014. http://hdl.handle.net/10284/4453.
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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária<br>A Endodontia é uma área da Medicina Dentária responsável pelo estudo da polpa dentária, de todo o sistema de canais radiculares e dos tecidos periapicais, bem como das doenças que os atingem.
Em casos de alterações por cárie, fraturas dentárias, trauma dentário, trauma ortodôntico, lesões endo-periodontais, necessidades protéticas e outras patologias Endodônticas, o tratamento Endodôntico está indicado, visando a manutenção do dente na cavidade oral e a saúde dos tecidos periapicais.
A imagiologia, área a que a Medicina Dentária recorre frequentemente, associa-se também, e cada vez mais, à Endodontia uma vez que tem vindo, nos últimos anos, a desenvolver novas tecnologias.
A Tomografia Computurizada De Feixe Cónico (CBCT) é uma dessas técnicas imagiológicas relativamente recentes, sendo que é um sistema radiológico que possibilita a visualização de imagens tridimensionais de áreas que se pretendam examinar. Assim, com esta opção imagiológica tornar-se-á mais fácil o diagnóstico, tratamento e controlo de diversas patologias. Endodontics is an area of dentistry responsible for study of dental pulp, of the whole system of root canals and Periapical tissues, as well as the diseases that affect them.
In cases of dental caries, dental fractures, trauma, endo-perio injuries, prosthetic needs and other pathologies, endodontic treatment may be the solution, as it helps to preserve and the periapical tissues health.
Imagiology, it´s a common area used in the Dentistry, and it´s associated more and more to Endodontics, as it has been developing new techniques in the last several years.
Cone Beam Computed Tomography (CBCT) is one of those new techniques, and it provides three-dimensional radiological image of the tooth areas that they wish to examine. This Imagiologic choice makes diagnosis and treatment of several deseases easier.
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La, Ciacera Giorgio. "Tomografia computerizzata a fascio conico (CBCT)." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12315/.
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Questo elaborato tratta le apparecchiature per la tomografia computerizzata a fascio conico (CBCT). Inizialmente sono descritte le caratteristiche dei raggi X ed il loro utilizzo in campo clinico, analizzando le varie tipologie di radiografia. Successivamente, si introduce il tomografo computerizzato, del quale si descrive la struttura e i principi di funzionamento, fino ad arrivare alla trattazione dei sistemi CBCT. Di questi viene studiato il funzionamento, il meccanismo di formazione delle immagini, gli ambiti di applicazione e i rispettivi vantaggi e limiti. Infine si analizza la dose di radiazione X emessa dall'apparecchiatura, studiando se il paziente corra rischi sottoponendosi a questi esami radiologici.
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Giles, David. "Cone-beam computed tomography: imaging dose during CBCT scan acquisition and accuracy of CBCT based dose calculations." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95242.
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Cone beam computed tomography (CBCT) is a recent development in radiotherapy for use in image guidance. Image guided radiotherapy using CBCT allows visualization of soft tissue targets and critical structures prior to treatment. Dose escalation is made possible by accurately localizing the target volume while reducing normal tissue toxicity. The kilovoltage x-rays of the cone beam imaging system contribute additional dose to the patient. In this study a 2D reference radiochromic film dosimetry method employing GAFCHROMICTM model XR-QA film is used to measure point skin doses and dose profiles from the Elekta XVI CBCT system integrated onto the Synergy linac. The soft tissue contrast of the daily CBCT images makes adaptive radiotherapy possible in the clinic. In order to track dose to the patient or utilize on-line replanning for adaptive radiotherapy the CBCT images must be used to calculate dose. A Hounsfield unit calibration method for scatter correction is investigated for heterogeneity corrected dose calculation in CBCT images. Three Hounsfield unit to density calibration tables are used for each of four cases including patients and an anthropomorphic phantom, and the calculated dose from each is compared to results from the clinical standard fan beam CT. The dose from the scan acquisition is reported and the effect of scan geometry and total output of the x-ray tube on dose magnitude and distribution is shown. The ability to calculate dose with CBCT is shown to improve with the use of patient specific density tables for scatter correction, and for high beam energies the calculated dose agreement is within 1%.<br>La tomographie par faisceaux conique (CBCT) informatisée a été récemment développée en radiothérapie pour l'utilisation de guidage par imagerie. La radiothérapie guidée par imagerie (IGRT) utilisant le CBCT, permet la visualisation des cibles à tissus mous et des structures critiques avant le traitement. En localisant précisément la cible, une « escalade » de dose est rendue possible et la toxicité des tissus sains est réduite. Les rayons-X à basse énergie (kilovoltage) du system d'imagerie du CBCT, contribue à une dose additionnelle pour le patient. Dans cette étude, une méthode dosimétrique utilisant un film 2D radiochromic (Gafchromic film, model XR-QA) a été employé pour mesurer des points de dose à la peau ainsi que des profiles de dose. Cette étude a été réalisée à l'aide d'un system d'Elekta XVI CBCT installé sur un accélérateur linéaire du Synergy. Le contraste des images quotidiennes du CBCT des tissus mous rend possible au niveau clinique l'utilisation de la radiothérapie adaptive. Dans le but de suivre la dose administrée au patient ou utiliser de la replanification en ligne pour la radiothérapie adaptive, les images CBCT doivent être utilisées pour le calcul de dose. Une calibration des unités de Hounsfield par méthode de correction de dispersion est examinée dans le cas de dose calculée dans des milieux hétérogènes pour les images CBCT. Trois unités de Hounsfield par table de calibration de densité sont utilisées pour chaque des quatre cas incluant des patients et un fantôme anthropomorphique. Le calcul de dose pour chaque cas est comparé avec les résultats cliniques standards de tomographie par faisceaux en éventail. La dose acquise avec le scanner est reportée et l'effet géométrique du scanner ainsi que le débit total du tube a rayon-X sur la magnitude et la distribution de la dose sont montrés. La capacité de calculer la dose avec un CBCT est présentée dans le but d'amélio
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Pichotka, Martin Peter [Verfasser], and Caroline [Akademischer Betreuer] Röhr. "Iterative CBCT reconstruction-algorithms for a spectroscopic Medipix-Micro-CT = Iterative CBCT Rekonstruktions-Algorithmen für ein spektroskopisches Medipix-Mikro-CT." Freiburg : Universität, 2014. http://d-nb.info/1115495674/34.
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Lalani, Sara. "Three-dimensional CBCT analysis of cranial base symmetry." Thesis, Boston University, 2015. https://hdl.handle.net/2144/37816.
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Thesis (MSD) --Boston University, Henry M. Goldman School of Dental Medicine, 2015 (Department of Orthodontics and Dentofacial Orthopedics).<br>Includes bibliographic references: leaves 37-42.<br>Background: Craniofacial skeletal asymmetry is a common finding in the general population that often goes undetected. Interest in this topic has led to many studies aimed at describing this type of asymmetry, its distribution and etioIogy. The cranial base, being cIosely related to the face and brain, is a key component in craniofacial growth and may also display varying amounts of asymmetry contributing to this anomaly. Though many studies have explored underlying skeletal asymmetry, most of them were limited by their two-dimensional method of investigation. With the advent of three-dimensional technology, more recent studies have had the advantage of studying the cranial base in its true anatomic form, resulting in greater accuracy of analysis. Despite access to this technoIogy, there is still a lack of literature regarding the cranial base in a normal population. Determining average skull base dimensions will provide a set of normative data that can be used as a reference for future studies.
Material and Methods: Pre-treatment Cone Beam Computed Tomography (CBCT) films of 160 esthetic human subjects previously used by another investigator were screened for use in our current research. These DICOM files were imported into InVivoDental5.3 software (Anatomage[TM]; San Jose, Calif.) for screening and 70 CBCT scans were selected for analysis. All patients were classified as cervical vertebral stage 4 and above. The images were oriented in all three planes of space for uniformity and 14 bilateral anatomic landmarks were identified on each scan. A mid-sagittal reference plane was created using crista galli as the origin, and extending a perpendicular passing through the middle of the right and left clinoid points connected by a line, and through posterior points basion and opisthion. Each landmark was given an x-, y- and z- coordinate representing its three dimensional position and bilateral linear measurements to the reference plane were recorded using the software system.
Statistical Analysis: InVivoDental5.3 software was used to calculate linear distances between each landmark and the mid-sagittal plane. This data was exported into Microsoft excel for analysis. Descriptive statistics of our sample and paired t-tests with a 5% significance level, or p value of 0.05, were performed.
Results: The means of the right and left measurements of each bilateral landmark were calculated along with their standard deviations. A comparison between right and left means was accomplished with the use of paired t-tests. 12 1andmarks did not show a statistical difference in their locations on either side of the mid-sagittal plane. However, the means of 2 landmarks were found to be statistically significant. These were euryon (p = 0.01) and the jugular foramen (p = 0.00)
Conclusion: The overall trend of our data indicated that the cranial base in a normal population, without craniofacial anomaly, displays symmetry, with the exception of the location of euryon and the jugular foramen. These findings are in accordance with those of similar three-dimensional studies. It is likely that the significant findings were due to tracing error, given the indiscrete location of euryon and the large, relatively asymmetric shape of the jugular foramen. However, if these structures are truly asymmetric, we can infer from our sample of symmetric patients, that there is no clinical relevance. Further studies with an increased sample size, additional landmarks or a more discrete sample can be performed to continue describing the skull base. The results of this study offer valuable reference data that can be used as a baseline for future studies.
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Katkar, Rujuta Amol. "Comparison of observer reliability of three-dimensional cephalometric landmark identification on subject images from Galileos and i-CAT CBCT." Thesis, University of Iowa, 2011. https://ir.uiowa.edu/etd/3478.
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Zimmerman, Jason Noah. "Reliability of upper pharyngeal airway assessment using dental CBCT." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62653.
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Introduction: Upper airway analysis is an often-cited use of CBCT imaging in orthodontics, however the reliability of airway measurements using this technology is not fully understood. The purpose of this study was to determine the intra-examiner and inter-examiner reliability of the complete process of volumetric and cross-sectional area assessments of the upper airway using CBCT imaging.
Methods: Five examiners of varying levels of education and clinical experience performed manual orientation, slice and threshold selection, and measured nasopharyngeal, oropharyngeal, hypopharyngeal, and total upper pharyngeal airway volumes in addition to minimum cross-sectional area on the CBCT images of 10 patients. All measurements were repeated after 4-weeks. Intra and inter-examiner reliability was calculated using ICC and 95% CI.
Results: Threshold selection showed poor intra and inter-examiner reliability, while minimum cross-sectional area showed moderate intra and poor inter-examiner reliability. Intra-examiner reliability of volumetric measurements varied based on the anatomical region assessed with ICC ranging from 0.747-0.976, and was worst for hypopharynx and best for the oropharynx. Inter-examiner reliability of volume measurements was generally lower, with ICC ranging from 0.175-0.945, and was worst for nasopharynx and best for the oropharynx.
Conclusions: This study, for the first time, assessed the reliability of upper airway analysis with CBCT when all steps of image processing and measurement are performed by each examiner. Reliability improved with examiner experience, though was generally low for the hypopharynx and nasopharynx volumes and overall minimal cross sectional area. The oropharyngeal volume was the only parameter to have excellent intra-examiner and inter-examiner reliability.<br>Dentistry, Faculty of<br>Graduate
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Junes, Prado Luisa. "Utilización de CBCT en retratamiento endodóntico selectivo no quirúrgico." Master's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/625916.
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El retratamiento de canales radiculares es una alternativa ante el fracaso endodóntico. Este procedimiento tiene como objetivo reducir los síntomas que pueden presentarse o agravarse posterior al tratamiento de endodoncia.
El procedimiento del retratamiento de canales sigue la premisa que aparentemente la calidad del material de obturación en todo el sistema de canales es deficiente, por consiguiente, todo el material debe ser retirado.
Actualmente, con mejores técnicas de análisis imagenológico es posible identificar el origen de la lesión apical, por lo tanto, es posible seleccionar los canales pulpares con tratamiento deficiente y poder ser tratados de forma individual.
De esta manera, el retratamiento selectivo de canales podría evitar el desgaste innecesario de canales en buen estado.<br>Root canal Retreatment is an alternative in the face off endodontic failure. This procedure aims to reduce the symptoms that may occur or worsen after the endodontic treatment.
The root canal retreatment procedure follows the premise that apparently the quality of the filling material in the entire canal system is deficient, therefore, all the material must be removed.
Currently, with better techniques of image analysis it is possible to identify the origin of the apical lesion, therefore, it is possible to select the pulp canals with poor treatment and be able to treat them individually.
In this way, the selective root canal retreatment could avoid the unnecessary wear of root canals in good condition.<br>Trabajo académico
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Wood, Ryan LaDell. "Factors Affecting Alveolar Bone Height Measurements from CBCT Images." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1331044145.
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Woland, Bradley David. "CBCT-derived norms for tip and torque in Caucasians." Thesis, Boston University, 2014. https://hdl.handle.net/2144/37824.
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Thesis (MSD) --Boston University, Henry M. Goldman School of Dental Medicine, 2014 (Department of Orthodontics and Dentofacial Orthopedics).<br>Includes bibliographic references: leaves 38-40.<br>Background: Previous CBCT studies have established standards for mesiodistal angulations and faciolingual inclinations of the dentition in a non-Caucasian population. These standards help ensure proper root positioning, since they are not based solely on the clinical crowns.
Objective: to use the USC root vector analysis to measure the tip and torque of teeth to establish Caucasian norms.
Methods: We measured and obtained mean mesiodistal and faciolingual angulations from each whole tooth from 34 pretreatment and 43 previously treated Caucasian patients, by using the University of Southern California root vector analysis program in Dolphin 3D. We used descriptive statistics to present normal torque and tip values. Two-Sample t-test was executed to compare right tip and torque values to the left side. One sample t-test was used to compare our Caucasian sample to the multi-ethnic sample in Tong et al. paper, and to compare pretreatment to post-treatment patients within the Caucasian group.
Results: Comparing right to the left tip and torque values in our sample showed no significant difference (P[greater than]0.05). We compared our study sample to the USC sample norm and we found that there was statistical significant difference in almost all tip and torque values (P[less than]0.05). We found no statistically significant difference in angulation of teeth between treated and untreated Caucasian patients.
Conclusion: We measured and obtained mean mesiodistal and faciolingual angulations from each whole tooth from 34 pretreatment and 43 previously treated Caucasian patients′ by using the University of Southem California root vector analysis program in Dolphin 3D. When comparing the right side to the left side of the treated and untreated Caucasian groups, there was no statistically significant difference between the measurements for either tip or torque. We found a statistically significant difference in angulation of teeth between Caucasian and USC populations. We found no statistically significant difference in angulation of teeth between treated and untreated Caucasian patients.
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Kördel, Mikael. "A Physical X-Ray Scintillator Detector Model for CBCT Imaging Applications." Thesis, KTH, Medicinsk bildfysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147690.
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Padala, Soumya. "A Grey-level Assisted Method for CBCT Alveolar Bone Height Measurements." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1396005811.
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Srinivasan, Soorya. "Reliability and Accuracy of Assessing TAD - Tooth Root Contact using CBCT." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1553782462280014.
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Kessling, Paul Christopher II. "Suppression of CBCT X-ray Scatter Using Bite Registration (PVS) Material." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594998120708499.
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Campbell, Matthew Stephen. "A Practical Method to Superimpose Sella Turcica in Serial CBCT Images." Master's thesis, Temple University Libraries, 2017. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/470228.
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Oral Biology<br>M.S.<br>Introduction: We argue, for studies of growth or treatment changes, superimposed CBCT images ought to be employed routinely. The location of 3D landmarks on curved structures, however, has been complex. In this study, a reliable method of CBCT superimposition was developed with the aid of AMIRA XImage® software. The specific focus was to develop a practical method for cranial base superimpositions at sella turcica in serial CBCT images. Subsequently, evaluations of the anterior curvature of hypophyseal fossa during growth were completed to confirm the stability. Comparisons of surface changes in the superimposed images in different regions were also made. Methods: Samples of pre- and post-orthodontic CBCT data were procured from Case Western Reserve University. Cranial base changes in 10 adolescent patients of Class I and II hypodivergent, normodivergent, and hyperdivergent malocclusions, were observed over an average interval of 2 years and 5 months. Cranial base models were superimposed using a rigid registration technique, and 3D models constructed from manual segmentation in the AMIRA software. Surface distance changes of the entire cranial base were compared to that of the anterior portion of sella turcica. Results: Mean surface distance changes for the entire cranial base and anterior sella were 0.73-1.57 ± 0.71-1.30 mm and 0.37-0.63 ± 0.29-0.43 mm, respectively. The area above a threshold of 0.5 mm was 61.02-74.11% (cranial base) and 40.70-50.94% (anterior sella) as well. Paired t-tests were applied to compare differences between the mean distance and area above the threshold for data of cranial base versus anterior sella. Both illustrated p-values less than 0.0001 and were statistically significant. Intra-rater reliability was evaluated by completing segmentation and registration three consecutive times on each CBCT volume. Mean surface differences were within 0.01 mm with the exception of one patient. In addition, all subjects exhibited less than 1.00% deviation except three patients, which deviated by 1.03%, 1.46%, and 1.64%, respectively. Conclusions: A practical method of superimposition of serial CBCT images was developed. Through production of color maps, the surface distance of the anterior portion of sella turcica was shown to change much less than the clivus and remaining cranial base structures in pre- and post-treatment scans of growing children. Lastly, the method of superimposition developed here may assist future studies of skeletal changes with accuracy.<br>Temple University--Theses
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Lindbäck, Elias. ""Imaging with CBCT and 4D-CT of objects moving with respiratory motions"." Thesis, Stockholms universitet, Medicinsk strålningsfysik (tills m KI), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-89053.
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AB S TRACT purpose : To further investigate the effects of respiratory motions on CBCT imaging, as well as 4D-CT examinations, with a future goal of using obtained results to implement new methods for individual margins and daily matching procedures into routine clinical practice. background : Since the implementation of CBCT combined with modern accelerators, a higher degree of accuracy has been made possible in RT. However, due to the slow gantry speed of linear accelerators, the imaging procedure of CBCT is a slow process which is thereby degraded by internal motion such as respiration. material and methods : Attain patient specific respiratory motion patterns from CBCT projection data of previous examinations. Utilize this data to perform simulations for both CBCT and 4D-CT using a steering system which allows for arbitrary motion patterns in the longitudinal direction. results : Various imaging with CBCT showed that the resulting images during respiratory motion, can be described by the Probability Density Function of the motion for as long as it does not cause related distortions. This also meant that convolution could be implemented as a model to estimate the CBCT images during oscillation, knowing the object and motion pattern. The 4D-CT examinations using the steering system showed that irregular motion patterns were less accurately described than regular patterns, making the actual motion an important feature to combine together with the measured amplitude. conclusions : It was made clear that CBCT images can be described by the PDF, and thus can be seen as a Color Intensity Projection of the object position. Also it has been shown that the projection data of CBCT images contains valuable information about the respiratory motion of the patient. Another conclusion is that with the help of fiducials, the position of the target within the respiratory cycle can be determined relative to the 4D-CT examination, enabling further input data as to the daily matching procedure, proper applied margins as well as dose to the OAR.
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Beshtawi, Khaled Raed. "The accuracy of the mental foramen position on panoramic radiographs and CBCT." University of the Western Cape, 2017. http://hdl.handle.net/11394/5953.
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Magister Scientiae Dentium - MSc(Dent) (Diagnostics and Radiology)<br>Data was analysed from 31 archived cone-beam computed
tomography (CBCT) images and Digital panoramic radiographs (DP) for the same patients
taken on the same x-ray machine (Carestream CS9000 3D). The position and demarcations
of mental foramen were identified and then compared by means of linear measurements
performed using the manufacturer provided software. Distances measured for the mental
foramen in CBCT reformatted panoramic views (CRP) and digital panoramic radiographs (DP)
were obtained and compared for both the vertical and horizontal positions. CBCT oblique
coronal views (CORO) were studied for the vertical position of the mental foramen and
compared to those obtained from CRP and DP for the same distance.
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Barateau, Anaïs. "Calcul de dose à partir d'images CBCT et IRM en radiothérapie externe." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1B064.
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Une radiothérapie externe repose sur l’acquisition d’une image scanner (computed tomography : CT) de planification. Celle-ci contient l’information des densités électroniques nécessaires au calcul de la dose à délivrer. Des images volumique, cone beam CT (CBCT), MV-CT ou imagerie par résonance magnétique (IRM), sont acquises pour le repositionnement du volume cible sous la machine de traitement. Ces images pourraient être utilisées pour quantifier l’impact dosimétrique des variations anatomiques pouvant survenir en cours de traitement. L’objectif de cette thèse était de développer, d’évaluer et de comparer des méthodes de calcul de dose à partir d’images CBCT et IRM, dans une perspective de radiothérapie adaptative guidée par la dose. Pour un calcul de dose à partir d’images CBCT, une méthode de deep learning a été comparée à trois méthodes de la littérature de la sphère ORL. Pour un calcul de dose sur IRM, neuf méthodes, dont une méthode atlas, une méthode patches et des méthodes de deep learning avec différentes architectures ont été comparées. De plus, les bénéfices dosimétriques de stratégies de radiothérapie adaptative par replanification (ORL) et par bibliothèque de plans de traitement (col de l’utérus) ont été évalués. En conclusion, les méthodes de deep learning pour générer des pseudo-CT sont prometteuses, car rapides et précises. Ces méthodes peuvent être utilisées pour un suivi de la dose en cours de traitement dans le cadre d’une radiothérapie adaptative<br>Standard external beam radiotherapy is based on a planning computed tomography (CT) scan. This CT provides electron densities required for dose calculation. 3D imaging such as cone beam CT (CBCT), MV-CT or magnetic resonance imaging (MRI), are acquired just before irradiation for target volume registration. These images could be used to quantify dosimetric impact of anatomical variations occurring during the treatment course. The objective of the thesis was to develop, evaluate and compare CBCT-based and MRI-based dose calculation methods, in a dose-guided adaptive radiotherapy perspective. For head-and-neck CBCT-based dose calculation, a deep learning method was compared to three other methods from literature. For prostate MRI-based dose calculation, nine methods including an atlas-based, a patch-based and deep learning methods with different architectures were compared. Moreover, dosimetric benefits of adaptive radiotherapy strategies (offline for head-and-neck and plan treatment library for cervix) were evaluated. To generate pseudo-CT from CBCT or MRI, deep learning methods are promising, since they are fast and accurate. These methods can be used for a dose monitoring during treatment course in an adaptive radiotherapy process
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Mohunta, Vrinda V. "Radiographic Appearance of Inter-occlusal Record Materials for CBCT Guided Implant Surgery." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1436203075.
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Gianquinto, Jared Robert. "A Method of Superimposition of CBCT Volumes in the Posterior Cranial Base." Master's thesis, Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/210320.
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Oral Biology<br>M.S.<br>Three dimensional imaging in the form of Cone Beam Computed Tomography has become prevalent in the field of orthodontics. Analytical methods of resulting volumetric data sets have not kept pace with the technology capable of producing them. Current 3D analysis techniques are largely adaptations of existing 2D methods, offering no clear diagnostic advantage over traditional imaging techniques in light of increased radiation exposure, and cannot be compared with norms generated from 2D image capture sources. In order to study morphology in 3D, data sets must be generated for longitudinal studies and native 3D analytical methods must also be developed. Existing methods of CBCT volume superimposition are cumbersome, involving complex software pipelines and multiple systems to complete the process. The goal of the current study was to develop a reproducible method of CBCT volume superimposition in the posterior cranial base in a single software package, and construct an easy to follow, step-by-step manual to facilitate future studies in craniofacial morphology. Existing anonymized sequential CBCT volumes of three subjects meeting inclusion criteria were obtained from the Kornberg School of Dentistry Department of Radiology. Volumes for each subject were imported into AMIRA software, resampled to a standardized 0.5 mm voxel size and superimposed with a mutual information algorithm. Posterior cranial base surface data was extracted using a semi-automatic technique. Resulting surface distance data was compiled and visualized through application of color maps. A streamlined image processing protocol was produced and documented in a detailed step-by-step manual. Surface distance analysis of serial segmentations was performed to verify reliability of the process. Surface distance deviations greater than 0.5 mm consistently fell below 0.2 percent of the total surface area. Sequential scan superimpositions of all three subjects exhibited mean surface distances of less than 0.15 mm. Two out of three subjects exhibited deviations of greater than 0.5 mm in less than 1 percent of the total surface area, suggesting consistent sub-voxel accuracy of the protocol.<br>Temple University--Theses
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Alghalib, Thamer Alsharif [Verfasser], Dirk [Akademischer Betreuer] Schulze, and Wael [Akademischer Betreuer] Att. "Influence of examiner’s assessment on the precision of linear measurements of CBCT." Freiburg : Universität, 2016. http://d-nb.info/1122743211/34.
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Dodd, M. N. "The use of CBCT as an aid to endodontic assessment of calcified canals." Thesis, University of Liverpool, 2018. http://livrepository.liverpool.ac.uk/3022895/.
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Varghai, Kaveh Varghai. "The Production of Hydroxyapatite Standards, Used for Post CBCT Scan Hounsfield Unit Calibration." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1505842174493682.
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Rost, Anya. "Using CBCT as a diagnostic tool for evaluation of infrabony defects in vivo." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3333.
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BACKGROUND: Clinicians rely on radiographs and clinical exam to assess infrabony defects. However, two-dimensional radiographs have many limitations. Three-dimensional imaging has shown promise and has provided more precise measurements of defects created in skulls. The aim of this study is to compare the diagnostic efficacy of cone beam computed tomography to clinical measurements in patients presenting with infrabony defects. METHODS: The study population included 20 patients with 25 infrabony defects. Clinical measurements of pocket depth (PD), gingival margin (GM), bone sounding (BS) were obtained and PD and BS were compared to CBCT measurements. RESULTS: The average difference between the means of measurements obtained by BS and by CBCT was 1.08mm with BS always being the greater value. BS measurement was statistically significantly different with p<0.05 from CAL and CBCT values. CONCLUSION: The CBCT provided measurements that are on average 1.08mm smaller than bone sounding measurements.
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Vijayan, Suvendra. "Reliability of 3D-printed mandibles constructed from CBCT volumes of different voxel sizes." Thesis, University of Iowa, 2018. https://ir.uiowa.edu/etd/6323.
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Objectives: The aim of the current study is to establish the reliability of linear cephalometric measurements made on mandibles and their respective 3D printed models created from different voxel resolutions from a cone beam CT machine.
Materials and methods: Ten dry mandibles obtained from the Department of Oral Pathology, Radiology and Medicine at The University of Iowa College Of Dentistry were used for this study. All mandibles were scanned on the i-CAT FLX cone beam CT machine (Imaging Sciences International, LLC, Pennsylvania, USA) using voxel resolutions of .30mm, .25mm and .20 mm in a 16cm x 8cm field of view using 360° rotation. The 3D models were reconstructed and saved as .STL files using 3D Slicer software and send to a 3D printer for printing. Two observers measured the 10 mandibles and 30 3D printed models. The measurement were repeated on 50% of the samples after at least one week interval. Cronbach’s alpha and intraclass correlation coefficient were calculated to measure reliability.
Results: Good to excellent interobserver and intraobserver reliability was achieved across most of the measurements. There was no difference in reliability across models made from different voxel sizes.
Conclusion: The current study successfully showed that the reliability of measurements made on 3D printed models of dry skull mandibles created using fused deposition modeling technique using images of different voxel sizes from an i-CAT FLX CBCT machine are valid, reproducible, and reliable and can be used for diagnostic and clinical purposes.
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Choi, Ella. "Phantom dosimetry of i-CAT CBCT and i-CAT panoramic radiographs in pediatric patients." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/48516.
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Objectives: To obtain head dimensions from patients who received dental CBCT at BC Children’s Hospital (BCCH), to apply this information to design and construct small child and adolescent head phantoms, and to measure and compare the absorbed radiation doses from CBCT and panoramic radiographs using small child, adolescent and adult head phantoms.
Materials and Methods: Patients who received dental CBCT at BCCH were surveyed. Head dimensions from each subject’s image were measured to develop adolescent and small child head phantoms. The most commonly used dental CBCT imaging protocols were examined. Absorbed doses were measured for small child, adolescent and adult head phantoms with i-CAT CBCT and Planmeca panoramic radiograph machines.
Results: In the patient survey, 32 patients met the inclusion criteria. The most common indications for CBCT referral were for orthodontic treatment, followed by craniofacial abnormality and cleft lip and palate. A small child phantom was developed to represent the child patients with craniofacial abnormality and an adolescent phantom was developed to represent healthy orthodontic patients. Absorbed radiation doses varied depending on machine, imaging protocol, size of phantom and location of the ion chamber in the phantoms. For CBCT images, the highest radiation was measured in the small child phantom while the lowest radiation was measured in the adult phantom. For panoramic radiographs, the i-CAT CBCT panoramic option was compared to the Planmeca panoramic radiograph machine. For both machines, the small child phantom measured the highest while the adult phantom measured the lowest radiation. For the adolescent phantom, lower values were measured with the Planmeca machine while lower values were measured with i-CAT CBCT panoramic option for the small child phantom.
Conclusion: Two groups of pediatric patients were referred for dental CBCT at BCCH: young patients with craniofacial abnormality and healthy adolescent patients for orthodontic assessment. A consistent trend was observed for both CBCT and panoramic radiographs: the highest dose was measured in the smallest phantom while the lowest dose was measured in the largest phantom. Radiation in pediatric population is more detrimental than in adult population and it is important to child size the dose and protocol.<br>Dentistry, Faculty of<br>Graduate
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Abouei, Elham. "Quantitative performance characterization of image quality and radiation dose for dental CBCT machine (CS9300)." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50297.
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Purpose: To characterize the performance of cone beam CT (CBCT) used in dentistry, investigating quantitatively the image quality and radiation dose during dental CBCT over different settings for partial rotation of the x-ray tube.
Methods: Image quality and dose measurements were done on a variable field of view (FOV) dental CBCT (Carestream 9300). X-ray parameters for clinical settings were adjustable for 2-10 mA, 60-90 kVp, and two optional voxel size values, with fixed time for each protocol and FOV. The phantoms were positioned in the FOV to imitate clinical positioning. Image quality was assessed by scanning a cylindrical poly-methyl methacrylate (PMMA) image quality phantom (SEDENTEXCT IQ), and the images were analyzed using ImageJ to calculate image quality parameters such as noise, uniformity, contrast to noise ratio (CNR), and spatial resolution. A protocol proposed by SEDENTEXCT, dose index 1 (DI1), was applied to dose measurements obtained using a thimble ionization chamber and cylindrical PMMA dose index phantom (SEDENTEXCT DI). Dose distributions were obtained using Gafchromic film.
Results: The image noise was 6-12.5% which, when normalized to the difference of mean voxel value of PMMA and air, was comparable between different FOVs. Uniformity was 93.5-99.7% across the images. CNR was 0.5-4.2, 0.2-4.6, 3.7-11.7, 4.3-17.8, and 6.3-14.3 for LDPE, POM, PTFE, air, and aluminum, respectively. The measured FWHM and spatial resolution were larger than the voxel size. FWHM were 0.49-0.65 mm; spatial resolution was 194.81-467.68. Dose distributions were symmetric about the rotation angle’s bisector. For large and medium FOVs at 4 mA, 80-90 kVp, and 180-250 μm, DI1 values were in the range of 1.26-3.23 mGy. DI1 values were between 1.01-1.93 mGy for small FOV (5x5 cm²) at 4-5 mA,75-84 kVp, and 200 μm.
Conclusion: Noise and spatial resolution decreased and the CNR increased by increasing kVp; the geometric distortion, AAV, FWHM were very similar or the same when increasing the kVp. When FOV size increased, image noise increased and CNR decreased. FWHM and spatial resolution have no correlation with the voxel size. DI1 values were increased by increasing tube current (mA), tube voltage (kVp), and/or FOV.<br>Science, Faculty of<br>Physics and Astronomy, Department of<br>Graduate
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Zekry, Ahmed Khaled Ahmed Abdin. "Facial alveolar bone wall width: a cone beam computed tomography (CBCT) study in Asians." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48395663.
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Background: The width of the facial alveolar bone wall is crucial for long term successful esthetic outcomes of implants immediately placed into extraction sockets. A threshold of 2 mm is recommended to minimize buccal vertical bone resorption.
Aim: To assess the width of the facial alveolar bone wall using cone-beam computed tomography images (CBCT).
Methods: Retrospective CBCT images were acquired from a representative sample of Asians using the i-CAT® classic system with a 0.4 mm voxel size. At random, 200 CBCT images were selected according to predefined criteria. The DICOM file was imported into the i-Cat Vision® software. In the panoramic screen, the middle of each tooth was selected and, in the sagittal window, the middle cross section was selected for performing the measurements using a computer. The vertical distance from the alveolar crest (BC) - CEJ was measured. The width of the facial alveolar bone wall was measured at three locations: 1, 3, and 5 mm apical to BC. Descriptive statistics, frequency analyses, and multi-level comparisons were performed.
Results: The sample consisted of 74 males and 126 females (mean age of 37.2 years; range 17-82 years). A total of 3618 teeth were assessed.
There was no significant difference between the values of right and left sides, or between genders. However, statistically significant differences were observed between age groups at all levels. The distance from CEJ-BC varied from 0.4 to 4mm, with an overall tendency to increase with age. The mean width of the facial alveolar bone wall at anterior teeth was 0.9 mm and increased towards posterior regions. Rarely, a width of 2 mm was yielded (0.6-1.8 % for anterior teeth, 0.7- 30.8 % for posterior teeth). At a 5mm distance from BC, minimal widths of facial alveolar bone were identified for the anterior teeth. The frequency of dehiscence ranged from 9.9- 51.6 % for anterior and 3.1- 53.6 % for posterior teeth, respectively.
Conclusion and clinical implications: A thin facial alveolar bone wall was usually present in both jaws. Hence, for most patients, adjunctive bone augmentation may be needed when installing implants in areas of esthetic concern.<br>published_or_final_version<br>Dental Surgery<br>Master<br>Master of Dental Surgery
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Li, Si. "Data acquisition modeling and hybrid coronary tree 3D reconstruction in C-arm CBCT imaging." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S133/document.
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L'angiographie coronarienne RX (ou coronarographie) reste la modalité de référence permettant de déterminer avec précision le degré et le nombre de sténoses coronariennes ainsi que le nombre de vaisseaux atteints. L'objectif de ce travail de thèse de doctorat concerne l'amélioration de la reconstruction 3D des coronaires afin d'améliorer le diagnostic, ainsi que la sécurité et la précision des interventions minimalement invasives. Dans un premier temps, une contribution majeure vise à améliorer l'étape de calibration du système d'imagerie rotationnelle R-X. Premièrement, nous avons donc proposé un nouvel algorithme de calibrage basé objet inspiré de la méthode de Xu et al, dédié au système robotisé Artis Zeego. Deuxièmement, nous transposons les géométries de projection dans le système de coordonnées du C-arm. Nous avons proposé des modèles de mouvement des géométries de projection en considérant objectivement et systématiquement tous les facteurs possibles. Ces modèles de mouvement permettent de simplifier la procédure de calibration en routine clinique. The résultats expérimentaux indiquent que les modèles de mouvement proposés ont une précision acceptable afin estimer les paramètres d'acquisition. Dans un second temps, une contribution majeure vise à proposer une nouvelle méthode de reconstruction des coronaires par compensation de mouvement. Les étapes de reconstruction sont: l'opérateur de projection, la segmentation des projections acquises, le recalage iconique, la reconstruction initiale et la reconstruction avec compensation de mouvement. Nous avons opté pour l'opérateur de projection Distance Driven simplifié proposé par Oukili. Nous avons adopté comme mesure de similarité l'information Mutuelle (MI) avec un terme de rigidité. Pour optimiser cette fonction de coût, nous avons utilisé la méthode Advanced Adaptive Stochastic Gradient Descent (ASGD). Nous avons adopté une reconstruction statistique itérative basée on MAP et l'a priori L0. Les résultats expérimentaux indiquent que la méthode proposée améliore visuellement la qualité de la reconstruction. Le contraste et les détails des reconstructions sont améliorés par compensation de mouvement<br>The rotational angiography RX of the coronaries is a standard modality to determine the degree and the number of the coronaries stenosis. The objective of this dissertation aims at improving the 3D reconstruction of the coronary arteries, which can improve the diagnosis, the security and the precision of the minimal invasive interventions.For the first part, the major contribution is improving the calibration procedure of the rotational R-X imaging system. First, we propose a new calibration algorithm based on the classical helical phantom on the Artis-Zeego system. Second, we transfer the geometries to the C-arm coordinate system. Last, we propose the movement models of the projection geometries objectively and systematically at 3 representative work positions. The movement models simplify the clinical procedures. The experiment results indicate that the proposed movement models have an acceptable precision to estimate the acquisition parameters.For the second part work, the major contribution is proposing a new reconstruction method by motion compensation. The steps of the reconstruction method include: the forward projection, the segmentation of the acquired projection, registration, the initial and motion compensated reconstruction. We adopt the advanced Simplified Distance Driven projector to generate the forward projection. We use the mutual information (MI) and rigidity penalty (RP) to be the similarity measure. We adopt the advanced Adaptive Stochastic Gradient Descent (ASGD) to realize the optimization. The initial and the compensated reconstruction are based on the MAP iterative reconstruction. The experiment results indicate that the proposed method improves the quality of the 3D reconstruction. The contrast and the details of the coronary arteries are improved by the proposed motion compensation reconstruction method
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Dhou, Salam. "IMAGE-BASED RESPIRATORY MOTION EXTRACTION AND RESPIRATION-CORRELATED CONE BEAM CT (4D-CBCT) RECONSTRUCTION." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/496.
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Accounting for respiration motion during imaging helps improve targeting precision in radiation therapy. Respiratory motion can be a major source of error in determining the position of thoracic and upper abdominal tumor targets during radiotherapy. Thus, extracting respiratory motion is a key task in radiation therapy planning. Respiration-correlated or four-dimensional CT (4DCT) imaging techniques have been recently integrated into imaging systems for verifying tumor position during treatment and managing respiration-induced tissue motion. The quality of the 4D reconstructed volumes is highly affected by the respiratory signal extracted and the phase sorting method used. This thesis is divided into two parts. In the first part, two image-based respiratory signal extraction methods are proposed and evaluated. Those methods are able to extract the respiratory signals from CBCT images without using external sources, implanted markers or even dependence on any structure in the images such as the diaphragm. The first method, called Local Intensity Feature Tracking (LIFT), extracts the respiratory signal depending on feature points extracted and tracked through the sequence of projections. The second method, called Intensity Flow Dimensionality Reduction (IFDR), detects the respiration signal by computing the optical flow motion of every pixel in each pair of adjacent projections. Then, the motion variance in the optical flow dataset is extracted using linear and non-linear dimensionality reduction techniques to represent a respiratory signal. Experiments conducted on clinical datasets showed that the respiratory signal was successfully extracted using both proposed methods and it correlates well with standard respiratory signals such as diaphragm position and the internal markers’ signal. In the second part of this thesis, 4D-CBCT reconstruction based on different phase sorting techniques is studied. The quality of the 4D reconstructed images is evaluated and compared for different phase sorting methods such as internal markers, external markers and image-based methods (LIFT and IFDR). Also, a method for generating additional projections to be used in 4D-CBCT reconstruction is proposed to reduce the artifacts that result when reconstructing from an insufficient number of projections. Experimental results showed that the feasibility of the proposed method in recovering the edges and reducing the streak artifacts.
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Huang, Hechang. "Effects of Orthodontic Treatment on Human Alveolar Bone Density Distribution." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1331134320.
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Packer, McKay Barlow. "Comparison of treatment planning decisions when combining CBCT and digital radiography verses digital radiography alone." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4140.
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Cone beam computed tomography (CBCT) is the recommended imaging modality of choice for evaluating previous endodontic treatment (1). The aim of this study was to compare treatment planning decisions made when evaluating previous endodontic treatment to determine if treatment planned and projected prognosis differs when digital radiography is used alone or in combination with CBCT. A retrospective chart review was conducted. Patients for whom a CBCT was taken were included in the study. Twenty-eight patients qualified. Patient’s periapical digital radiographs (Dexis©) were evaluated by 2 calibrated endodontists, a treatment plan was identified and a prognosis was projected. Later the same radiographs were viewed with CBCT scan. The CBCT provided significant information 75% of the time. CBCT provided the only information for an accurate diagnosis 17% of the time. Prognosis changed 38% of the time when CBCT was added. An unfavorable or questionable prognosis changed to favorable 30% of the time.
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Calil, Louise Resti. "Long-term periodontal status of maxillary central incisors after orthodontic traction: CBCT and clinical findings." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/25/25144/tde-19072018-111825/.
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Purpose: The aim of this study was to evaluate the buccal and lingual alveolar bone morphology and the periodontal clinical condition of impacted permanent maxillary central incisors at least 6 months after the orthodontic traction. Methods: This split mouth transversal study evaluated a sample of 11 patients a mean of 15.41 years after the orthodontic traction of unilateral impacted maxillary central incisor. The experimental group (TR) consisted of 11 impacted central incisors. The comparison group (NTR) consisted of 11 non-impacted contralateral teeth. High-resolution CBCT exams of central incisors were performed using Accuitomo (J. Morita, Kyoto, Japan). Cross section imagens passing through the center of maxillary central incisors were used to measure buccal and lingual alveolar bone level. Presence of fenestration, root dilacerations, root coverage, and position of the root apex were also assessed in the same images. Clinical parameters included the periodontal probing depth, attachment level, gingival bleeding index, plaque index, degree of gingival recession, amount of gingival mucosa and evaluation of interproximal papilla and black triangle. Digital model analysis included an assessment of clinical crown height and width. Intergroup comparisons were performed using paired t tests, McNemar and Wilcoxon tests (p<0.05). Pearson correlation coefficient was calculated to determine the relationship between the clinical and CBCT findings. Results: TR group showed a significantly thinner buccal bone plate thickness at the middle and apical root level compared to NTR group. A decreased buccal alveolar crest level was observed in TR group in comparison to NTR group. The TR group showed a greater frequency of buccal bone dehicences and root dilacerations than antimeres. Experimental group showed more gingival recession, a decreased amount of gingival mucosa and an increased clinical attachment level at the buccal aspect than the NTR group. Moderate inverse correlation was found between buccal bone plate thickness of central incisors and attachment level and moderate positive correlation was found between buccal alveolar crest height and attachment level Conclusions: The periodontal conditions of maxillary central incisors long-term after orthodontic traction are different compared to its antimere. A decreased thickness and height of buccal alveolar bone and gingival recessions were observed in central incisors 15 years after orthodontic traction.<br>Introdução: o objetivo deste estudo foi avaliar a morfologia óssea alveolar vestibular e lingual e a condição clínica periodontal de incisivos centrais superiores impactados há, pelo menos, 6 meses após o tracionamento ortodôntico. Material e Métodos: Este estudo transversal de boca dividida avaliou uma amostra de 11 pacientes com média de 15,41 anos após a mecânica de tração ortodôntica de incisivo central superior retido unilateral. O grupo experimental (TR) foi composto por 11 incisivos centrais retidos. O grupo controle (NTR) foi composto por 11 incisivos contralaterais irrompidos naturalmente. Exames de TCFC de alta resolução dos incisivos centrais foram realizados utilizando o Accuitomo (J. Morita, Kyoto, Japão). As imagens transversais que passaram pelo centro dos incisivos centrais superiores foram utilizadas para medir o nível ósseo alveolar vestibular e lingual. A presença de fenestração, dilaceração, recobrimento radicular e posição do ápice radicular também foram avaliados nas mesmas imagens. Os parâmetros clínicos incluíram profundidade de sondagem periodontal, nível de inserção clínico, índice de sangramento gengival, índice de placa, grau de recessão gengival, quantidade de mucosa queratinizada e avaliação da presença de triângulo negro na papila interproximal. A análise de modelo digital consistiu da avaliação da altura e largura da coroa clínica. As comparações intergrupos foram realizadas utilizando os testes de t pareado, McNemar e Wilcoxon (p<0,05). O coeficiente de correlação de Pearson foi calculado para determinar a relação entre os achados clínicos e TCFC. Resultados: o grupo TR apresentou uma espessura da tábua óssea vestibular significantemente mais fina em nível médio e apical da raiz, em comparação ao grupo NTR. Observou-se uma diminuição do nível da crista alveolar vestibular no grupo TR em comparação ao grupo NTR. O grupo TR mostrou uma maior frequência de deiscência óssea vestibular e dilaceração radicular quando comparado aos contralaterais. O grupo experimental revelou maior recessão gengival, diminuição da quantidade de mucosa gengival e maior do nível de inserção clínico na face vestibular, em comparação ao grupo NTR. Verificou-se uma correlação inversa entre a espessura da tábua óssea vestibular dos incisivos centrais e o nível de inserção clínico e uma positiva correlação entre a altura da crista alveolar vestibular e o nível de inserção, ambas moderadas. Conclusões: As condições periodontais dos incisivos centrais superiores em longo prazo após o tracionamento ortodôntico são diferentes em comparação aos contralaterais. Uma menor espessura e altura óssea alveolar vestibular, bem como presença de recessões gengivais foram observadas nos incisivos centrais 15 anos após o tracionamento ortodôntico.
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Patel, Alpesh. "Sensitivity and Accuracy of Cone Beam Computed Tomography in Diagnosing Osseous Defects at the Mandibular Condyle." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1363606389.
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Liu, shang lun. "PREVALENCE OF ODONTOGENIC RELATED MAXILLARY SINUS PATHOLOGY IN PATIENTS OF TEMPLE UNIVERSITY KORNBERG SCHOOL OF DENTISTRY." Master's thesis, Temple University Libraries, 2016. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/376252.
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Oral Biology<br>M.S.<br>ABSTRACT Objectives: Cone beam computerized tomography use is becoming more common in preparation for surgical planning and treatment diagnosis by clinicians. The scanning result gives clinicians a more accurate understanding of each patients’ anatomy, which aids in designing better treatment plan, avoidance of vital anatomy, etc. Modern treatments involving extraction of teeth has become more sophisticated due to advent of dental implant treatment. Along with the procedure, more sophisticated treatment techniques involving manipulation of sinus has flourished. Traditional periapical and panoramic radiograph are not as adapt at identifying sinus pathologies. As patients age, proximity of sinus floor and apex of teeth may become closely related where possibility of one affecting another is observed. This study aims to study the prevalence of odontogenic related pathologies in relation to maxillary sinus in the population who had CBCT images taken at Temple University Kornberg School of Dentistry. The study also looks in detail the relationship of such pathology in relation to teeth status, age, gender, and ethnicity. Methods: 821 CBCT scans completed at Temple University Kornberg School of Dentistry Department of Oral Maxillofacial Radiology from January 1st, 2009 to July 31, 2013 were evaluated with iCAT computer imaging software. Patients under 18, no posterior dentition, or complete edentulous were excluded from the study. A total of four hundred fourty four (444) CBCT scans were included in the study. Patients with odontogenic related maxillary sinus pathology were selected and teeth status, age, gender and ethnicity recorded. Individual scans had sinus pathology identified and examined for proximity and relationship to respective tooth/teeth. Each individual tooth’s status were also recorded. Chi-square test was conducted to verify validity Results: After reviewing 680 scans, only 444 were included in the study due to exclusions. Scans were subdivided by age (18-35: 77, 36-53: 113, 54-71: 188, 72> : 46), gender (280 male and 164 female), ethnicity (African American 86, Asian 45, Caucasian 291, Hispanic 22), tooth status (caries, 26, crown 87, healthy 31, impacted 11, root canal 88, restoration 58), tooth position ( 3rd molar 9, 2nd molar 86, 1st molar 138, 2nd premolar 20, 1st premolar 6, canine 3). Overall 63.06% of scans were classified as healthy, and 36.04% were classified as presenting odontogenic related maxillary sinus pathology. None of the parameters showed significant predilection to odontogenic related pathology, however, 1st molar has the highest risk of exhibiting pathology in the maxillary sinus with 2nd molar second. The pathology incidence rates are slightly higher in male patients 41% vs 34%. Age is not a significant factor as all age groups demonstrates similar incidence rate except 72> group. Dentition status showed root canal and crown being the most commonly associated with pathology at 29% each. In Caucasian population, crown and root canal was most commonly related. African American was restoration and healthy teeth. Asian population had the most link with large restorations. Conclusions: Maxillary 1st molar is the most commonly involved tooth with maxillary sinus pathologies with 2nd molar as second most common. Caucasian individuals had the most odontogenic related pathologies. In general, crown and root canal are associated with a significant number of pathologies found in the sinus and should be evaluated prior to any surgical evaluation prior to any sinus manipulative surgery or odontogenic treatment.<br>Temple University--Theses
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Anamali, Sindhura. "Prevalence of the posterior superior alveolar canal assessed with cone beam computed tomography." Thesis, University of Iowa, 2012. https://ir.uiowa.edu/etd/1425.
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Octave, Nadia. "La radiothérapie adaptative et guidée par imagerie avec la technologie Cone-Beam CT : mise en oeuvre en vue du traitement de la prostate." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30207/document.
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L'imagerie est maintenant partie intégrante des traitements de radiothérapie. Avec la technologie CBCT embarquée sur les appareils de traitement, l'imagerie tomographique permet non seulement de repositionner fidèlement le patient tout au long de son traitement mais aussi d'adapter la planification initiale aux modifications quotidiennes de volume. C'est la radiothérapie adaptative, objet des travaux de cette thèse. Nous avons établi les limites techniques de précision de repositionnement des équipements utilisé. Ensuite, à partir des acquisitions CBCT quotidiennes de patients traités pour la prostate, nous avons élaboré une stratégie de traitement basée sur une banque de plans personnalisés. Nous avons mis au point une méthode semi-automatique de sélection du plan de traitement du jour qui a montré une efficacité supérieure à la sélection par des opérateurs expérimentés. Enfin, nous avons quantifié les doses additionnelles à la dose thérapeutique associées à l'utilisation quotidienne de l'imagerie CBCT. En conclusion, on peut dire qu'avec l'imagerie CBCT embarquée, on peut voir ce que l'on veut traiter, irradier ce que l'on a vu et contrôler ce qu'on a traité<br>Imaging is now fully integrated in the radiation therapy process. With on-board CBCT systems, tomography imaging allows not only patient positioning but also treatment planning adaptation with patient anatomy modifications, throughout the entire treatment. This is called adaptive radiation therapy, and is the main subject of this PhD thesis. During this work, we measured the repositioning accuracy of the system used. We also developed a treatment strategy using daily CBCT images and a personalized plan database to adapt treatment plan to patient anatomy. We found a way to select the daily treatment plan that shows superiority over operator selection. Then we also quantified the additional dose delivered while using this technique and the impact with regards to the risks added to patients. As a conclusion, with CBCT imaging, radiation therapy has entered an era where one can see what need to be treated, can treat what has been seen and can control what has been treated
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Ljungsell, Emma, and Elin Luoma. "Utvärdering av cone beam computed tomography som metod vid fraktur i övre extremiteter : - En jämförelse mellan modaliteter." Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för naturvetenskap och biomedicin, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-44642.
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Bakgrund: Cone beam computed tomography (CBCT) är en form av datortomografi vanlig inom odontologi och börjar utnyttjas mer inom ortopedisk diagnostik. Frakturer i övre extremiteter är vanligt förekommande i samband med trauma. Konventionell röntgen är oftast förstahandsmetod men kan inte alltid utesluta scaphoideumfraktur, som obehandlad kan ge allvarliga konsekvenser. Syfte: Syftet är att utvärdera CBCT som metod vid fraktur i övre extremiteter genom att jämföra med andra modaliteter. Metod: Arbetet är en systematisk litteraturstudie. Databaserna Medline, CINAHL och PubMed användes. Endast artiklar publicerade inom de senaste 10 åren inkluderades. Kvalitetsgranskning utfördes med protokoll från Hälsohögskolan i Jönköping. Resultat: 15 artiklar inkluderades i resultatet. Faktorer som identifierades var konkordans, stråldos, bildkvalitet, diagnostisk kvalitet samt patienttolerans och undersökningstid. CBCT hade överlägsen eller likvärdig konkordans. I åtta av nio artiklar visades CBCT ha lägre stråldos än jämförande modalitet. Generellt var bildkvaliteten god för CBCT. Skilda resultat uppkom för diagnostisk förmåga. Patienttoleransen var högre för CBCT än multidetektor-CT (MDCT) gällande tid. Slutsats: CBCT påvisade god bildkvalitet och diagnostisk förmåga till en relativt låg stråldos, samt högre sensitivitet och specificitet än konventionell röntgen. På grund av skillnader i mätinstrument i det insamlade materialet kan ingen definitiv slutsats dras. Vidare studier inom ämnet rekommenderas.<br>Background: Cone beam computed tomography (CBCT) is a method commonly used in odontology and is becoming more used in orthopedic diagnostics. Fractures in upper extremities are a common occurrence in trauma. Conventional radiography is often the firsthand method but cannot always exclude scaphoid fractures, which untreated can have serious consequences. Purpose: The purpose is to evaluate CBCT as an examination method for fractures in the upper extremities by comparing with other modalities. Method: This study is a systematic literature review. The databases used were Medline, CINAHL and PubMed. Only articles published within the last 10 years were included. A quality audit was implemented using a protocol from Jönköping University. Results: 15 articles were included. The factors identified were observer agreement, radiation dose, image quality, diagnostic quality, patient tolerance and image duration. CBCT had a better or equal observer agreement. In eight out of nine articles, CBCT was shown to have a lower radiation dose than its comparative modality. In general, a good image quality in CBCT was found. Differing results were found about diagnostic ability. The patient tolerance was higher for CBCT than multidetector-CT (MDCT) regarding image duration. Conclusions: CBCT demonstrated a good image quality and diagnostic ability to a relatively low radiation dose, and a higher sensitivity and specificity than conventional radiography. Due to differences in measuring instruments used in the gathered material, no definitive conclusion could be drawn. Further studies in the subject is recommended.
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Chilà, Deborah. "Dose tracking in radiation oncology using daily CBCT: effects of physical parameters on dose calculation accuracy." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20587/.
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The availability of cone beam computerized tomography (CBCT) images at the time of treatment has opened possibilities for recalculations and tracking of the delivered dose, becoming an effective tool for adaptive radiotherapy. A significant component in the accuracy of dose recalculation on CBCT images is the calibration of the Hounsfield units (HU) to density.
The aim of this thesis, developed at the Policlinic of Modena, is to assert a methodology for the characterization of the HU-to-density calibration curve, and to evaluate the impact of the calibration phantom inserts composition and phantom volume on dose calculation accuracy.
The HU-to-density calibration curves from four different phantoms were measured and compared. The HU output of a kV CBCT scan depends on the physical parameters of the phantom density inserts, with particular reference to the atomic number (Z), due to the photoelectric effect which is the main radiation-matter interaction at kV energies. The phantom radial diameter also influences the HU values on the image. The effect of scattering and beam hardening was examined as a function of phantom diameter, founding a high deviation on the HU value of the same density insert when varying the radial diameter of the phantom, especially for high densities. When we are dealing with CBCTs also the acquisition parameters influence the resulting image, that’s why we will show that a protocol-specific calibration curve is needed. The resulting calibration curves were used to compare the calculated doses against planned ones. The percent difference between recalculated and planned dose was obtained for chosen clinically important dose levels and a box plot analysis was conducted.
Results show that the best calibration curve for dose recalculation on CBCT images has been obtained when a human-tissue-equivalent inserts are used and when the radial diameter of the phantom is close to the dimensions of the real patient.
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Guijarro, Martínez Raquel. "Cone-beam computerized tomography (CBCT) evaluation of the upper airway in the context of orthognathic surgery." Doctoral thesis, Universitat Internacional de Catalunya, 2014. http://hdl.handle.net/10803/134767.
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Upper airway analysis has become a key focus of investigation in the fields of Orthognathic Surgery and Orthodontics. This is due to the well-acknowledged relationship between a narrow upper airway and sleep-disordered breathing, and to the association between airway configuration and specific craniofacial phenotypes. As a result of the advancement of the skeletal insertions of the suprahyoid and velopharyngeal muscles, maxillomandibular advancement with counterclockwise rotation has established itself as an effective strategy to increase the pharyngeal airway volume, with subsequent improvement in sleep-disordered breathing symptomatology. These changes can be assessed objectively with cone-beam computerized tomography (CBCT), which has provided a paradigm shift in cranio-maxillofacial imaging due to its capacity to obtain a thorough two- and three-dimensional evaluation of the upper airway at relatively modest costs, with greater accessibility, lower radiation, and shorter scanning times. The most important contributions of this PhD Thesis are the following: 1) Paper one provides the first systematic review of the literature concerning upper airway imaging and analysis with CBCT. Results confirm that CBCT is indeed an accurate and reliable tool for upper airway analysis. Nevertheless, specific problems related to the image acquisition process and to image processing and analysis persist. 2) Paper two is a preliminary CBCT evaluation of the effect of mono- and bimaxillary advancement on the volume of the upper airway. Results showed a systematic volumetric increase for all groups. However, bimaxillary and mandibular advancement achieved a greater percentage increase than maxillary advancement alone. These results suggest the influence of mandibular advancement on the posterior airway space’s dimensions is greater than the effect of the forward movement of the maxilla. 3) Based on the results of the previous two papers, paper three was aimed at providing clinical three-dimensional anatomical limits for the upper airway subregions, translating them into accurate and reliable cephalometric landmarks in CBCT data, and validating the proposed measuring protocol. Our proposed protocol for upper airway subregion analysis proved to be anatomically logical, technically feasible, and statistically reliable.
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Jonczyk, Martin [Verfasser]. "Diagnostische Genauigkeit und Dosisreduktion vaskulärer und perkutaner Interventionen mittels periinterventioneller Cone Beam Computertomographie (CBCT) / Martin Jonczyk." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2021. http://d-nb.info/1236572882/34.
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Duggan, Sayward. "Alveolar Ridge Dimension Analysis Following Socket Preservation Using Clinical Assessment and Cone Beam Computed Tomography (CBCT)." VCU Scholars Compass, 2001. http://scholarscompass.vcu.edu/etd/2433.
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AIM: Extraction of a tooth can lead to alveolar ridge resorption which can be minimized by socket preservation. The aim of this study is to analyze vertical and horizontal alveolar ridge dimensions clinically and by CBCT immediately following extraction and 3-4 months following socket preservation. METHODS: The preserved group (P) consisted of 20 patients with1-2 non-molar teeth requiring extraction with socket preservation, while the control group (C) consisted of 5 patients requiring extraction alone. An acrylic stent was fabricated presurgically in order to measure vertical and horizontal ridge dimensions clinically and radiographically immediately following extraction and 3-4 months following socket preservation. RESULTS: Overall, P sites gained ridge height and lost minimal ridge width over 3-4 months, while C sites lost both ridge height and width. Preserved sites in which the teeth were extracted due to caries had the most significant gain in the radiographic vertical occlusal dimension (RVO). Overall, high correlations were found between the clinical and radiographic measurements at the initial surgery and at the 3-4 month follow up. CONCLUSIONS: The preserved group had minimal ridge resorption and more socket bony fill when compared to the non-preserved group 3-4 months following tooth extraction, especially when the tooth was extracted due to caries. Additionally, the CBCT can be a useful diagnostic tool to evaluate socket preservation healing, as it compares well to clinical assessments of socket healing.
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Mariani, Chiara. "La kV Cone Beam CT (kV-CBCT) in radioterapia guidata dalle immagini (IGRT): misure di dose e ottimizzazione di un protocollo di acquisizione clinico." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14220/.
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Scopo: Il presente lavoro di tesi, svolto presso le Unità Operative di Radioterapia e di Fisica Sanitaria dell’Ospedale Bellaria di Bologna, si pone l’obiettivo di valutare la dose erogata al paziente in seguito all’acquisizione di immagini CT volumetriche prima del trattamento radiante. Inoltre, si presenta una procedura per ottimizzare la dose dovuta a tali procedure di imaging.
Materiali e Metodi: Si è misurato il parametro “CTDI” (Computed Tomography Dose Index) quale indice dosimetrico correlato alla dose assorbita dal paziente sottoposto a kV-CBCT. Le misure sono state effettuate con una camera a ionizzazione di tipo “pencil”, lunga 10 cm, in un apposito fantoccio in polimetil-metacrilato avente 5 alloggiamenti per la camera a ionizzazione (4 in periferia e 1 al centro). Sono state effettuate misure di dose sia per i protocolli di acquisizione di immagini di kV-CBCT (“preset”) forniti dalla casa costruttrice, sia per quelli modificati, per diverse esigenze cliniche, dall’utente. Infine, allo scopo di ottimizzare la dose dovuta alla kV-CBCT, si è agito sul parametro radiologico dei mAs/frame, abbassando tale valore fino al punto oltre il quale un ulteriore abbassamento avrebbe causato un detrimento della qualità di immagine, non più accettabile dal punto di vista clinico.
Risultati: Nel lavoro, sono state effettuate e presentate circa 90 misure sperimentali di CTDI. I risultati relativi alle misure dei preset clinici di fabbrica hanno confermato i valori dichiarati dal costruttore. Un preset clinico utilizzato frequentemente nella pratica clinica è stato ottimizzato, riducendone la dose erogata al paziente del 20%.
Conclusioni: In questo lavoro di tesi sono state effettuate misure di dose in kV-CBCT sia per preset di acquisizione forniti dalla ditta costruttrice sia per i protocolli personalizzati dall’utente. Per il preset ottimizzato, è stato raggiuto un buon compromesso tra il risparmio di dose erogata al paziente e la qualità dell’immagine ottenuta.
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Albertini, Ascanio. "Validazione preliminare all'utilizzo di Cone Beam CT su distretti anatomici "non convenzionali": confronto di dose al paziente e image quality su immagini acquisite con TAC convenzionale." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22943/.
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La “Cone Beam Computed Tomography” è una tecnica di scansione del corpo umano prevalentemente in uso in campo odontoiatrico, maxillo
facciale o come riferimento nei sistemi di radioterapia. Diversi studi hanno valutato l’impiego di tale tecnologia anche nell’analisi di altre regioni del corpo, in virtù principalmente del suo basso costo se confrontato con CT convenzionali, che ad oggi rappresentano il “gold standard” in ambito
clinico/radiologico.
In questa tesi si presenta una ricerca bibliografica sull’uso della CBCT su distretti anatomici periferici e per i quali la CBCT è ancora considerata “tecnica non convenzionale”. Nell’analisi degli articoli riportati, si è posta particolare attenzione ai parametri dosimetrici e di qualità immagine, al fine di valutare le prestazioni della CBCT in questi ambiti, chiarendo criticità e pregi delle metodiche tomografiche, supportando, come richiesto ad un fisico che si approcci alla medicina, l’eventuale clinico nella valutazione della fattibilità/utilità della CBCT anche per questi distretti anatomici.
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McLaughlin, Victoria L. "Can Application of Artifact Reduction Algorithm or Increasing Scan Resolution Improve CBCT Diagnostic Accuracy of TAD - Tooth Root Contact?" The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1616485015766912.
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Awadi, Mona, Heeyeon Suh, Joorok Park, and Heesoo Oh. "OROPHARYNGEAL AIRWAY CHANGES FOLLOWING ORTHODONTIC TREATMENT OF ANTERIOR OPEN BITE IN GROWING VS NON-GROWING PATIENTS." Scholarly Commons, 2020. https://scholarlycommons.pacific.edu/dugoni_etd/8.
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Introduction: Orthodontic treatment of anterior open bite can result in a counter-clockwise rotation of the mandible and a more ideal forward position of the tongue. Usually this movement is thought to increase the oropharyngeal airway. The primary aim of the present study was to evaluate changes in vertical dimension and airway in AOB patients following orthodontic treatment. Methods: 52 subjects were included in this retrospective study of anterior open bite malocclusion treated in the graduate orthodontics clinic at the University of the Pacific, Arthur A. Dugoni School of Dentistry between 2006 – 2019. Cephalometric and airway measurements were done by 2 judges. Intraclass correlation coefficient (ICC) was used to evaluate inter-judge reliability for evaluating airway volume and MCA measurements. Chi-square tests were used to compare proportions. Unpaired t-tests were used to compare mean differences and paired t-tests were used to compare pre- and post-treatment changes. Results: More vertical control and intrusion of molars was seen in non-growing (NG) subjects. There was more successful open bite correction in NG subjects. Even though there was a reduction in FMA, LFA, improved incisor position and open bite correction, there was not much influence on airway dimensions. There was no statistically significant change in airway in growing (G) and NG subjects when looking at the whole sample. Conclusion: With correction of an anterior open; intrusion of molars and a more forward mandibular position result. However, these changes did not result in an increase in oropharyngeal airway in our study.
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Kortam, Sahira Ibrahim. "Buccal Bone Changes With Self Ligating Brackets Versus Conventional Brackets. A Comparative Study." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1268085301.
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Kim, Daniel Muhun. "PREVALENCE OF MAXILLARY SINUS PATHOLOGY IN PATIENTS AT TEMPLE UNIVERSITY SCHOOL OF DENTISTRY- A COMPARATIVE STUDY." Master's thesis, Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/504558.
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Oral Biology<br>M.S.<br>Objectives: There is increasing research regarding pathology of the maxillary sinus in dentistry. This may be attributed to the increasing routine use of cone beam computerized tomography (CBCT) for diagnosis and treatment planning of complex dental treatments, and incidental findings identified by clinicians during the process. This study aims to compare two different CBCT viewing software programs, and evaluate their detection of pathological findings in the maxillary sinus of a group of patients at Temple University School of Dentistry. Methods: A total of 316 CBCT scans taken on 176 females and 140 males (202 Caucasian, 69 African-American, 30 Asian, and 15 Hispanic) between 2009 and mid- 2013 by the Division of Oral & Maxillofacial Radiology at Temple University School of Dentistry were evaluated using i-CAT and INFINITT viewing software programs. The CBCT scans were examined with both viewing programs, and classified each time by independent evaluators as yielding one of 5 categories of maxillary sinus pathology as follows: healthy status with mucosal thickening ≤ 3 millimeters, mucosal thickening > 3 millimeters, polypoidal mucosal thickening, partial opacification, or complete opacification. Results: The i-CAT viewing program revealed 193 (61.1%) scans with a healthy maxillary sinus presenting with mucosal thickening ≤ 3 millimeters, and 123 (38.9%) scans yielding various forms of maxillary sinus pathology. In comparison, the INFINITT viewing program found 194 (61.4%) scans with healthy maxillary sinus conditions without pathology, and 122 (38.6%) scans with various types of maxillary sinus pathology. The difference in detection of maxillary sinus pathology between the i-CAT and INFINITT viewing programs was not statistically significant. Conclusions: The i-CAT and INFINITT viewing software programs for evaluation of human CBCT scans used in dental treatment planning provided nearly identical information relative to detection of maxillary sinus pathology. This suggests that both viewing programs may be employed interchangeably by clinicians in their pre- treatment evaluation of the maxillary sinus in dental patients.<br>Temple University--Theses
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Bernades, Mayordomo Ramon. "Análisis volumétrico mediante cbct de la región anterior del maxilar como zona donante de múltiples injertos óseos." Doctoral thesis, Universitat Internacional de Catalunya, 2016. http://hdl.handle.net/10803/386471.
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L'objectiu d'aquest estudi va ser analitzar mitjançant CBCT el volum, densitat i morfologia de l'os disponible a la regió anterior del maxil·lar com a zona donadora potencial d'empelts ossis. Es van avaluar tres zones independents: procés palatí del maxil·lar (PPM), espina nasal anterior (ENA) i os subnasal (SN). L'últim es va estudiar de forma bilateral independent (SND, SNE). Es van examinar 100 estudis CBCT. L'anàlisi morfomètrica va comprendre càlculs de volums, densitats així com mesures lineals. Es van descobrir possibles correlacions entre aquests paràmetres i les relacions d'aquests amb les característiques demogràfiques dels subjectes estudiats. L'estudi va involucrar 52 dones i 48 homes (49.6 ± 14.5 anys). Les mitjanes dels volums obtinguts van ser 2.41 ± 0.72 cm3 (PPM), 0.46 ± 0.16 cm3 (ENA), 0.58 ± 0.2 cm3 (SND) 0.57 ± 0.21 cm3 (SNE). La regió anterior del maxil·lar disposa de tres zones potencials (PPM, ENA, SN) on obtenir empelts ossis d'una grandària significativa com per tenir-les present en la restauració de defectes ossis propers.<br>El objetivo de este estudio fue analizar mediante CBCT el volumen, densidad y morfología del hueso disponible en la región anterior del maxilar como zona dadora potencial de injertos óseos. Se evaluaron tres zonas independientes: proceso palatino del maxilar (PPM), espina nasal anterior (ENA) y hueso subnasal (SN). El último se estudió de forma bilateral independiente (SND, SNI). Se examinaron 100 estudios CBCT. El análisis morfométrico comprendió cálculos de volúmenes, densidades así como mediciones lineales. Se averiguaron posibles correlaciones entre tales parámetros y las relaciones de estos con las características demográficas de los sujetos estudiados. El estudio involucró 52 mujeres y 48 varones (49.6 ± 14.5 años). Las medias de los volúmenes obtenidos fueron 2.41 ± 0.72 cm3 (PPM), 0.46 ± 0.16 cm3 (ENA), 0.58 ± 0.2 cm3 (SND) 0.57 ± 0.21 cm3 (SNI). La región anterior del maxilar dispone de tres zonas potenciales (PPM, ENA, SN) donde obtener injertos óseos de un tamaño significativo como para tenerlas presente en la restauración de defectos óseos cercanos.
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Rahmat, Roushanak. "Monitoring of lung cancer patients during radiotherapy using combined texture and level set analysis of CBCT images." Thesis, Heriot-Watt University, 2017. http://hdl.handle.net/10399/3349.
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In the UK, radiotherapy (RT) contributes to a large amount of lung cancer treatment while its imaging information is limited to computed tomography (CT) and cone beam CT (CBCT) images. The oncologists defines the gross tumour volume (GTV) manually on the planning-CT images before any treatment starts. Manual contouring suffers from many disadvantages and the bad quality of CBCT images makes it very challenging for the clinicians to observe tumour behaviour in the time of treatment. CBCT is the only kind of image available throughout the whole course of RT which is used in the mechanical procedure of adjusting patient position before starting each session of treatment and is not generally used by clinicians for monitoring the tumour. The goal of this thesis is to develop a tumour detection model of non-small cell lung tumours on CBCT images in the course of treatment. By developing this process clinicians will be greatly aided in their role, helping them to detect lung tumours to allow better diagnosis and improving patient treatment outcome. Therefore a new segmentation approach is proposed as combined texture analysis and level set model. It has the potential capability to track the variation of the tumour shape over time of treatment solely using CBCT images, and evaluate the accountability of RT for different patients. The texture analysis, second-order statistics obtained from gray level co-occurrence matrices (GLCM), highlight the tumour boundary and help Chan-Vese and Li level set models convergence in the segmentation process. Further on a new parallel level sets model is proposed by combining Chan-Vese and Li models in the concept of vector-valued image level set. This new approach overcomes the difficulties in the parameter settings of current models by giving more freedom of choice in tuning parameters as well as selecting level set models. All proposed models were evaluated on the dataset of fifty different patients suffered from non-small cell lung cancer. For the validation procedure, qualitative analysis was carried out by an oncologist as there is no ground truth in each CBCT image during RT. The decision of the oncologist based on patient history has proven the results of this work. For quantitative analysis, the Dice coefficient is used to evaluate the tumour segmentation results on CBCT compared to GTV on CT images prior to treatment to evaluate the amount of changes especially after one third of RT on CBCT #10. Additionally, the proposed segmentation models had the accuracy of almost 90% to the GTV delineated by the oncologist for the only one patient in the dataset having GTV on CBCT images which proved the ability of these models for further analysis during the absence of GTV on CBCTs. For improving this research and helping the clinicians at most, the proposed segmentation model can be used as a notification model to assist clinicians for a better understanding of the tumour during RT and subsequent use in offline adaptive radiotherapy (ART).