Дисертації з теми "Head and neck radiotherapy"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Head and neck radiotherapy.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Head and neck radiotherapy".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
Beasley, William. "Optimising adaptive radiotherapy for head and neck cancer." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/optimising-adaptive-radiotherapy-for-head-and-neck-cancer(96e831b0-751a-454d-8a6d-4dd490b6a88f).html.
Повний текст джерелаАнотація:
Anatomic changes occur throughout head and neck radiotherapy, and a new treatment plan is often required to mitigate the resulting changes in delivered dose to key structures. This process is known as adaptive radiotherapy (ART), and can be labour-intensive. The aim of this thesis is to optimise ART, addressing some of the technical and clinical challenges facing its routine clinical implementation. Optimising the frequency and timing of adaptive replanning is important, and it has been shown here that intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) are equally robust to weight loss during head and neck radiotherapy. Plan adaptation strategies that have previously been developed for IMRT are therefore applicable to VMAT.Contour propagation is an important component of ART, and it is essential to ensure that propagated contours are accurate. A method for assessing the suitability of a metric for measuring automatic segmentation accuracy has been developed and applied to the head and neck. For the parotids and larynx, metrics based on surface agreement were better than the commonly used Dice similarity coefficient. By establishing a consensus on which metrics should be used to assess segmentation accuracy, comparison of different algorithms is more objective and should lead to more accurate automatic segmentation. A novel method of assessing contour propagation accuracy on a patient-specific basis has also been developed. This was demonstrated on a cohort of head and neck patients and shows potential as a tool for identifying propagated contours that are subject to a high degree of uncertainty. This is a novel tool that will increase the efficiency of automatic segmentation and, therefore, ART.Optimum ART requires consideration of different radiotherapy-related toxicities, and image-based data mining is a powerful technique for spatially localising dose-response relationships. Correction for multiple comparisons through permutation testing is essential, but has so far only been applied to categorical data. A novel method has been developed for performing permutation testing and image-based data mining with a continuously variable clinical endpoint. Application to trismus for head and neck radiotherapy identified a region with a dose-response relationship in the ipsilateral masseter. Sparing this structure during radiotherapy should reduce the severity of radiation-induced trismus. ART mitigates the dosimetric effects of anatomic changes, and this thesis has addressed technical and clinical challenges that have so far limited its clinical implementation. Detailed knowledge of dose-response relationships will enable selection of patients for ART based on potential clinical benefit, and accurate contour propagation will make ART more efficient, facilitating its routine implementation.
2
Bhide, Shreeang Arvind. "Optimization of intensity modulated radiotherapy in head and neck cancer." Thesis, Institute of Cancer Research (University Of London), 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511161.
Повний текст джерела
3
Lei, Mary Wei-Ching. "Image guided intensity modulated radiotherapy in head and neck cancer." Thesis, University of Surrey, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.600034.
Повний текст джерелаАнотація:
Image Guided Intensity Modulated Radiotherapy (IG-IMRT) incorporates novel imaging strategies into IMRT planning and delivery. FDG-PET/CT imaging may be used to identify potentially radioresistant tumour cell populations in head and neck cancer (HNC). Dose-painting with IMRT is a novel technique which provides an opportunity to widen the therapeutic window by dose escalation to radioresistant subvolumes. The purpose of this thesis was to evaluate the feasibility of th is technique, to provide methodology for identification of the FDG-avid region and to inform on a reasonable dose level to use in a future phase I clinical study investigating dose-painting to the FDG-avid target volume. This technique requires confidence in the quality of geometric and dosimetric accuracy of delivery and this issue was investigated in this thesis. Pre-clinical work included a comparison of five different FDG segmentation techniques. One of these techniques was used to identify the FOG-avid biological volume selected to receive dose-painting with IMRT in a planning study. Four dose levels were tested. Radiobiological modelling was used to determine an optimal dose level as the basis for a future clinical study and to determine the impact of using different FDG segmentation techniques. A clinical study was performed in patients with HNC to compare in -room volumetric imaging - cone beam computed tomography (CBCT) - with planar kilovoltage (kV) electronic portal imaging (EPI) for aspects of image guidance and to inform on appropriate planning margins. Pre-clinical work suggested that dose-painting with IMRT to the FOG-avid subvolume would be associated with increases in estimated tumour control probability (TCP) and with acceptable increases in normal tissue complication probability (NTCP). Verification using CBCT provided accurate data to guide treatment delivery and appropriate planning margins. The findings reported in this thesis provide valuable information that will inform the design of future clinical studies.
4
Leslie, Martin David. "Salivary gland function after radiotherapy for head and neck cancer." Thesis, University College London (University of London), 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341706.
Повний текст джерела
5
Ostyn, Mark R. "Reducing Uncertainty in Head and Neck Radiotherapy with Plastic Robotics." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5558.
Повний текст джерелаАнотація:
One of the greatest challenges in achieving accurate positioning in head and neck radiotherapy is that the anatomy at and above the cervical spine does not act as a single, mechanically rigid body. Current immobilization techniques contain residual uncertainties that are especially present in the lower neck that cannot be reduced by setting up to any single landmark. The work presented describes the development of a radiotherapy friendly mostly-plastic 6D robotic platform for positioning independent landmarks, (i.e., allowing remote, independent positioning of the skull relative to landmarks in the thorax), including analysis of kinematics, stress, radiographic compatibility, trajectory planning, physical construction, and phantom measurements of correction accuracy. No major component of the system within the field of imaging or treatment had a measured attenuation value greater than 250 HU, showing compatibility with x-ray-based imaging techniques. Relative to arbitrary overall setup errors of the head (min = 1.1 mm, max = 5.2 mm vector error) the robotic platform corrected the position down to a residual overall error of 0.75 mm +/- 0.33 mm over 15 cases as measured with optical tracking. This device shows the potential for providing reductions to dose margins in head and neck therapy cases, while also reducing setup time and effort.
6
Andrews, Nigel Anthony. "Intrinsic cellular radiosensitivity in head and neck cancer." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367189.
Повний текст джерела
7
Patterson, Joanne Margaret. "Swallowing in head and neck cancer patients treated by (chemo) radiotherapy." Thesis, University of Newcastle Upon Tyne, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.545765.
Повний текст джерела
8
Urbano, Maria Teresa Guerrero. "Evaluation of intensity modulated radiotherapy in head and neck and pelvic malignancies." Thesis, Institute of Cancer Research (University Of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510356.
Повний текст джерела
9
Ho, Kean Fatt. "Optimising dose escalated intensity modulated radiotherapy (IMRT) in head and neck cancer." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508596.
Повний текст джерела
10
Ramadaan, Ihab Safa. "Validation of Deformable Image Registration for Head & Neck Cancer Adaptive Radiotherapy." Thesis, University of Canterbury. Physics and Astronomy, 2013. http://hdl.handle.net/10092/8083.
Повний текст джерелаАнотація:
Anatomical changes can have significant clinical impact during head and neck radiotherapy. Adaptive radiotherapy (ART) may be applied to account for such changes. Implementation of ART to alter dose delivery requires deformable image registration (DIR) to assess 3D deformations. This study evaluates the performance and accuracy of a commercial DIR system for clinical applications.
The investigations in this project were carried out using images of induced changes in two standard radiotherapy phantoms (RANDO® and CIRS®) and one in-house built phantom. CT image data before and after deformation of the phantoms were processed using Eclipse / SmartAdapt® v.10 system employing a Demons-based algorithm. A DIR protocol was designed, and algorithm performance was assessed quantitatively, using volume analysis and the Dice Similarity Index (DSI), and also evaluated qualitatively. In addition, algorithm performance was assessed for 5 head and neck cancer patients using clinical CT images. Each original planning CT image containing contours of 10 volumes of interest including treatment target volumes and organs at risk was deformed to match a second CT image acquired during the course of the treatment. The original structures were deformed, copied onto the target image and compared to reference contours drawn by 3 radiation oncologists.
Phantom investigations gave varied results with average DSI scores ranging from 0.69 to 0.93, with an overall average of 0.86 ± 0.08. These quantitative results were reflected qualitatively, with generally accurate matching between reference and DIR-generated structures. Although air gaps in the phantoms compromised algorithm performance and gave rise to physically aberrant results. Clinical results were generally better with a DSI range of 0.75-0.99 and an overall average of 0.89 ± 0.05, suggesting high DIR accuracy. Qualitatively, some minor contour deformations were noted, as well as artefacts in the axial direction that were due to the CT slice resolution (3 mm) that was used to scan the patients. In addition, contour propagation between images using DIR reduced the time required by physicians to contour the images of head and neck cancer patients by ~47%.
This study demonstrated that deformable image registration using a Modified Demons algorithm yields clinically acceptable results and time-saving benefits in contouring that improve clinical workflow. The study also showed that it is feasible to incorporate deformable image registration as part of an adaptive radiotherapy strategy for head and neck cancer, provided further studies are designed to carry out accurate and verifiable dose deformation.
11
Maraveyas, Anthony. "Refinement of targeted radiation strategies for the treatment of head and neck squamous cell carcinoma." Thesis, Imperial College London, 1995. http://hdl.handle.net/10044/1/8275.
Повний текст джерела
12
Lundmark, Martin. "Clinical evaluation of atlas-based segmentation for radiotherapy of head and neck tumours." Thesis, Umeå universitet, Institutionen för fysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-45571.
Повний текст джерелаАнотація:
Background Semi-automated segmentation using deformable registration of atlases consisting of pre-segmented patient images can facilitate the tedious task of delineating structures and organs in patients subjected to radiotherapy planning. However, a generic atlas based on a single patient may not function well enough due to the anatomical variation between patients. Fusion of segmentation proposals from multiple atlases has the potential to provide a better segmentation due to a more complete representation of the anatomical variation. Purpose The main goal of the study was to investigate potential operator timesaving from editing of atlas-based segmentation compared to manual segmentation for head & neck cancer. Materials and Methods A commercial atlas-based segmentation software (VelocityAI from Nucletron AB) was used together with several expert generated and protocol-based atlases of delineated CT images to create multiple atlas segmentations through deformable registration. The atlas that was considered most universal was selected to construct single atlas segmentation proposals. For fusion of the multiple atlas segmentations an in-house developed algorithm, including information of local registration success was used in a MATLAB-environment1. The algorithm uses weighted distance map calculations where weights represent probabilities of improving the segmentation results. Based on previous results1 the probabilities were estimated using the cross correlation image similarity measure evaluated over a region within a certain distance from the segmentation. Ten patients were incorporated in the study. Each patient was delineated three times, (a) manually by the radiation oncologist, (b) with a single atlas segmentation and (c) with a fusion of multiple atlas segmentations. For the methods (b) and (c) the radiation oncologist corrected the proposed segmentations blindly without using the result from method (a) as reference. For case (c) a total number of 11 atlas segmentations were used. The time spent for segmenting or editing the segmentation proposals by the radiation oncologist was recorded separately for each method and each individual ROI. In addition a grading was used to score how helpful the candidate segmentation proposals were for the structure delineations. The Dice Similarity Coefficient, the Hausdorff distance and the volume were used to evaluate the similarity between the delineated structures. Results The results show a time reduction in the order of 40% when the radiation oncologist only has to correct the multiple atlas-based segmentation proposal compared to manual segmentation. When using single atlas the corresponding figure is 21%. Conclusions Using atlas-based segmentation can reduce the time needed for delineation in the head and neck area of patients admitted for radiotherapy. 1C. Sjöberg and A. Ahnesjö, Evaluation of atlas-based segmentation using probabilistic weighted distance maps, Manuscript, Uppsala University, 2011Bakgrund Atlasbaserad, semiautomatisk segmentering skulle kunna användas för att underlätta den för onkologen tidskrävande uppgiften med att manuellt segmentera strukturer och organ i patienter vid behandlingsplanering inför strålbehandling. Tidigare segmenterade atlaspatienter ger med hjälp av deformeringsalgoritmer segmenteringsförslag för strukturer i den aktuella patienten. Dessa kan sedan kontrolleras och editeras av onkologen med en tidsbesparing gentemot manuell segmentering som följd. En atlas som baserats på en enstaka individ (singelatlas) kan dock ha begränsningar när det gäller att täcka de anatomiska variationer som finns mellan olika patienter. Därför har metoder med fusionering av multipla segmenteringsförslag från en databas bestående av ett antal sedan tidigare segmenterade patienter (fusionerad multipelatlas) potential att ge ett bättre segmenteringsresultat. Syfte Huvudsyftet med arbetet var att undersöka de möjliga tidsbesparingar för onkologen som kan åstadkommas när editering av atlasbaserad segmentering används vid planering inför strålbehandling i huvud- och halsområdet istället för manuell segmentering Material och metoder En kommersiell, atlasbaserad segmenteringsprogramvara (VelocityAI från Nucletron AB) användes i studien. Genom att låta en erfaren onkolog segmentera ett antal CT-studier (11 st) enligt ett vedertaget protokoll skapades en databas av atlaser som sedan, via deformerbara registreringar, kunde generera lika många segmenteringsförslag för en nytillkommen patient. Den enskilda atlas som ansågs mest representativ valdes till att framställa segmenteringsförslaget för metoden med singelatlas. Till metoden med fusionerade multipla atlaser användes en lokalt utvecklad MATLAB-algoritm baserad på viktade distansmappar. Vikterna representerar sannolikheten för förbättrat segmenteringsresultat och baseras på tidigare resultat1 där sannolikheterna bestämts utifrån en beräkning av likheterna mellan bilderna i ett visst område från den specifika segmenteringen. Tio patienter har inkluderats i studien. Varje patient segmenterades tre gånger, (a) manuellt, (b) med singelatlas och (c) med fusionerade multipla atlaser. För metoderna (b) och (c) editerades sedan segmenteringsförslagen av onkologen utan att denne fick använda resultatet från metod (a) som referens. För fallet med fusionerade multipla atlaser, (c), användes databasen med 11 atlaser. Tiden onkologen behövde för segmentering respektive editering av segmenteringsförslaget uppmättes i varje enskilt fall för jämförelse. Onkologen fick även göra en bedömning av hur hjälpsamt segmenteringsförslaget var i samband med editeringen. För utvärdering av resultaten användes Dice’s similaritetskoefficient, Hausdorff’s distansmått samt strukturernas volym. Resultat Resultaten visar på att en tidsbesparing i storleksordningen 40 % är rimlig när onkologen editerar förslag från fusioneringen av multipla atlassegmenteringar i jämförelse med manuell segmentering. Vid användning av singelatlas är motsvarande siffra 21 %. Slutsatser Användandet av atlasbaserad segmentering kan reducera tidsåtgången för segmentering av patienter inför strålbehandling i huvud-halsområdet. 1C. Sjöberg and A. Ahnesjö, Evaluation of atlas-based segmentation using probabilistic weighted distance maps, Manuscript, Uppsala University, 2011
13
Webster, Gareth John. "Intensity-Modulated Radiotherapy for the Head and Neck : Improvements in Planning and Delivery." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509060.
Повний текст джерела
14
Brown, Elizabeth M. "Biologically guided adaptive radiotherapy treatment planning for virally-mediated head and neck cancer." Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/98899/1/Elizabeth_Brown_Thesis.pdf.
Повний текст джерелаАнотація:
This thesis developed predictive models and risk profiles for pre-treatment identification of suitable adaptive radiotherapy candidates, from a cohort of oropharyngeal and nasopharyngeal cancer patients. This unique prospective approach could facilitate effective implementation of head and neck cancer adaptive radiotherapy into radiotherapy departments in Australia and internationally, through forward planning and appropriate resource allocation. Predicting those patients more likely to need adaptive radiotherapy in an efficient and judicious manner provides numerous benefits to radiotherapy departments across the world and ultimately, the patients under our care.
15
Tang, Nin-fai Francis, and 鄧年輝. "Monte Carlo dose calculations in quality assurance for IMRT of head and neck cancers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40203797.
Повний текст джерела
16
Newbold, Katie Lindsay. "The application of advanced imaging techniques to radiotherapy planning in head and neck cancer." Thesis, Institute of Cancer Research (University Of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498512.
Повний текст джерела
17
Berthon, Beatrice. "Optimisation of Positron Emission Tomography based target volume delineation in head and neck radiotherapy." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/69184/.
Повний текст джерелаАнотація:
Automatic segmentation of tumours using Positron Emission Tomography (PET) was recommended for radiotherapy treatment (RT) planning of head and neck (H&N) cancer patients, and investigated in the scientific literature without reaching a consensus on the optimal process. This project aimed at evaluating the performance of PETCbased automatic segmentation (PETCAS) methods and developing an optimal PETC AS process to be used at Velindre Cancer Centre (VCC). For this purpose, ten algorithms were implemented to represent the most promising PETCAS approaches from a systematic review of the literature. The algorithms’ performance was evaluated on filled phantom inserts with variable size, geometry, tumour intensity and image noise. The impact of thick insert plastic walls on both image quantification and segmentation was thoroughly assessed. The PETCAS methods were further applied to realistic H&N tumours, modelled using a printed subresolution sandwich phantom developed and calibrated in house. Results showed that different PETCAS performed best for different types of target objects. An Advanced decision TreeCbased Learning Algorithm for Automatic Segmentation (ATLAAS) was therefore developed and validated for the selection of the optimal PETCAS approach according to the target object characteristics. Finally, a protocol was designed for the use of PETCAS within RT planning at VCC. The protocol was used retrospectively on a group of 10 oropharyngeal cancer patients, and the results highlighted the additional information brought by PET beyond anatomical imaging. In a prospective study on 10 additional patients, PETCAS replaced manual PET/CT delineation, and accounted for up to 33% of the modifications of manually drawn CT/MRI contours to derive the final planning contour. This study demonstrated the usefulness and reliability of the PETCAS method in RT planning, and led to modifying the clinical workflow for H&N patients at VCC. This work has the potential to be extended to other tumour sites and institutions.
18
Kuo, Michael Jeo-Ming. "Aberrations of chromosome arms 5q and 8p in squamous cell carcinomas of the head and neck." Thesis, University of Birmingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340558.
Повний текст джерела
19
Chan, Sze-man, and 陳詩敏. "A clinical guideline to manage radiotherapy induced oral mucositis in head and neck cancer patients." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44622934.
Повний текст джерела
20
Ryalat, Mohammad. "Automatic construction of immobilisation masks for use in radiotherapy treatment of head-and-neck cancer." Thesis, University of East Anglia, 2017. https://ueaeprints.uea.ac.uk/66573/.
Повний текст джерелаАнотація:
Current clinical practice for immobilisation for patients undergoing brain or head and neck radiotherapy is normally achieved using Perspex or thermoplastic shells that are moulded to patient anatomy during a visit to the mould room. The shells are “made to measure” and the methods currently employed to make them require patients to visit the mould room. The mould room visit can be depressing and some patients find this process particularly unpleasant. In some cases, as treatment progresses, the tumour may shrink and therefore there may be a need for a further mould room visits. With modern manufacturing and rapid prototyping comes the possibility of determining the shape of the shells from the CT-scan of the patient directly, alleviating the need for making physical moulds from the patients’ head. However, extracting such a surface model remains a challenge and is the focus of this thesis. The aim of the work in this thesis is to develop an automatic pipeline capable of creating physical models of immobilisation shells directly from CT scans. The work includes an investigation of a number of image segmentation techniques to segment the skin/air interface from CT images. To enable the developed pipeline to be quantitatively evaluated we compared the 3D model generated from the CT data to ground truth obtained by 3D laser scans of masks produced by the mould room in the frame of a clinical trial. This involved automatically removing image artefacts due to fixations from CT imagery, automatic alignment (registration) between two meshes, measuring the degree of similarity between two 3D volumes, and automatic approach to evaluate the accuracy of segmentation. This thesis has raised and addressed many challenges within this pipeline. We have examined and evaluated each stage of the pipeline separately. The outcomes of the pipeline as a whole are currently being evaluated by a clinical trial (IRAS ID:209119, REC Ref.:16/YH/0485). Early results from the trial indicate that the approach is viable.
21
Carr, Simon David. "Assessing the effects of radiotherapy on head and neck squamous cell carcinoma using microfluidic techniques." Thesis, University of Hull, 2013. http://hydra.hull.ac.uk/resources/hull:8396.
Повний текст джерелаАнотація:
Objective The aim of this study was to investigate how HNSCC tissue biopsies maintained in a pseudo in vivo environment within a bespoke microfluidic device, respond to radiation treatment. Materials and Methods 35 patients with HNSCC were recruited; in addition liver tissue from 5 Wistar rats was used. A glass microfluidic device was used to maintain the tissue biopsy samples in a viable state. Rat liver was used to optimise the methodology. HNSCC was obtained from patients with T1-T3 laryngeal or oropharyngeal SCC; N1-N2 metastatic cervical lymph nodes were also obtained. Irradiation consisted of single doses of between 2 Gy and 40 Gy and a fractionated course of 5x2 Gy. Cell death was assessed in the tissue effluent using the soluble markers LDH and cytochrome c, and in the tissue by immunohistochemical detection of cleaved cytokeratin18 (M30 antibody). Radiation-induced DNA strand breaks were detected using the TUNEL assay. Results A significant surge in LDH release was demonstrated in the rat liver after a single dose of 20 Gy; in HNSCC it was seen after 40 Gy, compared to the control. There was no significant difference in cytochrome c release after 5 Gy or 10 Gy. M30 demonstrated a dose-dependent increase in apoptotic index for a given increase in single dose radiation. There was a significant increase in apoptotic index between the non-irradiated HNSCC tissue and irradiated tissue and between the tissue irradiated with 1x2 Gy and 5x2 Gy. As with the apoptotic index, there was a significant increase in radiation-induced DNA breaks between the non-irradiated and the irradiated tissue and between the tissue irradiated with 1x2 Gy and 5x2 Gy. Conclusion This microfluidic technique can be used to study the effects of radiation on HNSCC tissue. The device was capable of maintaining the HNSCC in a viable state, without it undergoing significant apoptosis or DNA damage and can be used to demonstrate the relationship between radiotherapy dose and radiation-induced cell death using tissue-based cell death markers. This study is a significant step towards achieving the ultimate goal of developing this device as a tool, capable of predicting a patient’s response to radiotherapy prior to the commencement of treatment.
22
Pow, Ho-nang Edmond. "Oral health and quality of life after intensity-modulated head and neck radiotherapy for nasopharyngeal carcinoma /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36749333.
Повний текст джерела
23
Pow, Ho-nang Edmond, and 鮑浩能. "Oral health and quality of life after intensity-modulated head and neck radiotherapy for nasopharyngeal carcinoma." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B4501565X.
Повний текст джерела
24
Nguyen, Nam, Paul Vos, Vincent Vinh-Hung, Misty Ceizyk, Lexie Smith-Raymond, Michelle Stevie, Benjamin Slane, et al. "Feasibility of image-guided radiotherapy based on helical tomotherapy to reduce contralateral parotid dose in head and neck cancer." BioMed Central, 2012. http://hdl.handle.net/10150/610349.
Повний текст джерелаАнотація:
BACKGROUND:To evaluate the feasibility of image-guided radiotherapy based on helical Tomotherapy to spare the contralateral parotid gland in head and neck cancer patients with unilateral or no neck node metastases.METHODS:A retrospective review of 52 patients undergoing radiotherapy for head and neck cancers with image guidance based on daily megavoltage CT imaging with helical tomotherapy was performed.RESULTS:Mean contralateral parotid dose and the volume of the contralateral parotid receiving 40Gy or more were compared between radiotherapy plans with significant constraint (SC) of less than 20Gy on parotid dose (23 patients) and the conventional constraint (CC) of 26Gy (29 patients). All patients had PTV coverage of at least 95% to the contralateral elective neck nodes. Mean contralateral parotid dose was, respectively, 14.1Gy and 24.7Gy for the SC and CC plans (p<0.0001). The volume of contralateral parotid receiving 40Gy or more was respectively 5.3% and 18.2% (p<0.0001)CONCLUSION:Tomotherapy for head and neck cancer minimized radiotherapy dose to the contralateral parotid gland in patients undergoing elective node irradiation without sacrificing target coverage.
25
Goodall, Benjamin David. "An exploration of the experience of undergoing radiotherapy for head and neck cancer patients : a biopsychosocial approach." Thesis, University of Hull, 2007. http://hydra.hull.ac.uk/resources/hull:15098.
Повний текст джерелаАнотація:
Aims: The objective of this research was to explore the changes in mood, memory and attention over the course of radiotherapy for treatment of head and neck cancer. This was with the aim of understanding head and neck cancer patients within the context of their illness and treatment; the biopsychosocial approach was used to explore this. To this end participants were asked for their subjective views on the process of undergoing radiotherapy treatment. Method: The study employed a prospective, small numbers design with repeated measures. Seven patients who were diagnosed with cancer of the larynx between August 2005 and March 2006 were invited to participate in the study. Five participants completed the measures prior to radiotherapy, post-radiotherapy and at three-month follow-up. Results: Participants reported changes in mood, memory and attention. Mood was found to decrease, with increased levels of both anxiety and depression reported. especially in the final two weeks of treatment. Memory and attention fluctuated over the course of treatment for all participants. Trends in the results are reported, along with the observation that there is great variability between individuals. which is important when considering the treatment and support of head and neck cancer patients. Conclusions: The biopsychosocial approach may be helpful in considering patients with head and neck cancers, as it provides a framework for staff to consider all of the factors that interact to affect how patients adjust to their illness and cope with the treatment process.
26
SCALCO, ELISA. "Evaluation of morphological and structural variations in parotid glands during radiotherapy in the head and neck district." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/50419.
Повний текст джерелаАнотація:
The treatment of head and neck cancer (HNC) patients is one of the widest applications of radiation treatment. One of the main organs involved in dose delivery and playing a relevant role in the quality of life of patients treated for HNC is the parotid gland, the major salivary gland, whose damage causes a pathologic condition called xerostomia. During the treatment, HNC patients may undergo significant anatomical changes; it was generally reported that parotids shrink during RT with a shift of the center of mass (COM) toward the midline. These modifications cause a translation of the glands into the high dose region, thus the effective delivered dose on parotids is significantly higher than that planned.
Therefore, the study of local changes in parotid glands due to irradiation is still an open challenge, and the exploitation of the information content in medical images acquired during the radiation treatment is of practical interest for the non-invasiveness of these techniques. The aim of this work was thus the evaluation of morphological and structural modifications induced by RT on parotid glands using image-based indices extracted from CT images acquired during the treatment. In particular, in this PhD project it was proposed to estimate morphological changes by the deformation of the glands, evaluated by applying a non-rigid registration method expressly optimized and validated on CT images of the HN district. Secondly, a method of image analysis based on textural feature extraction was proposed to characterize structural variations of parotid tissue. All these methods were evaluated and optimized for the clinical problem and all these parameters were studied in relation to dosimetric and clinical indices and to the clinical outcome, in order to better assess their contribution in this research field.
Parotid deformation was here estimated through an image registration and contour propagation method, based on Free Form Deformation and Mutual Information. A deep validation of this method was performed to assess the accuracy of contour propagation method, to ensure a reliable quantification of parotid deformation. The quantification of parotid deformation was carried out starting from the estimated deformation field, by calculating the Jacobian index, while the structural characterization of parotid tissue was performed by the extraction of features related to the intensity patterns of the image, quantified by texture analysis.
We evidenced that parotid shrinkage is highly related to low dose DVH values; at the same time, density variation measured after RT is significantly correlated with volume decrease, suggesting that the loss of acinar cells and the consequent increase in the percentage of the fatty component is related to the decrease in functionality. We proved that the major reduction in density is concentrated in the first half of the treatment, while the decrease in volume and in tissue complexity is quite constant during the whole treatment. Finally, we found that the most accurate prediction of parotid shrinkage is achieved by the combination of geometrical and structural variations measured in the first two weeks and that the early prediction of xerostomia score was preliminary achieved by early density and volume variation.
27
Rodrigues, Joana de Matos. "From genes to radioresistance in head and neck squamous cell carcinoma." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/16133.
Повний текст джерелаАнотація:
Mestrado em Biomedicina MolecularHead and Neck Cancers (HNC) are a group of tumours located in the upper aero-digestive tract. Head and Neck Squamous Cell Carcinoma (HNSCC) represent about 90% of all HNC cases. It has been considered the sixth most malignant tumour worldwide and, despite clinical and technological advances, the five-year survival rate has not improved much in the last years. Nowadays, HNSCC is well established as a heterogeneous disease and that its development is due to accumulation of genetic events. Apart from the majority of the patients being diagnosed in an advanced stage, HNSCC is also a disease with poor therapeutic outcome. One of the therapeutic approaches is radiotherapy. However, this approach has different drawbacks like the radioresistance acquired by some tumour cells, leading to a worse prognosis. A major knowledge in radiation biology is imperative to improve this type of treatment and avoid late toxicities, maintaining patient quality of life in the subsequent years after treatment. Then, identification of genetic markers associated to radiotherapy response in patients and possible alterations in cells after radiotherapy are essential steps towards an improved diagnosis, higher survival rate and a better life quality. Not much is known about the radiation effects on cells, so, the principal aim of this study was to contribute to a more extensive knowledge about radiation treatment in HNSCC. For this, two commercial cell lines, HSC-3 and BICR-10, were used and characterized resorting to karyotyping, aCGH and MS-MLPA. These cell lines were submitted to different doses of irradiation and the resulting genetic and methylation alterations were evaluated. Our results showed a great difference in radiation response between the two cell lines, allowing the conclusion that HSC-3 was much more radiosensitive than BICR-10. Bearing this in mind, analysis of cell death, cell cycle and DNA damages was performed to try to elucidate the motifs behind this difference. The characterization of both cell lines allowed the confirmation that HSC-3 was derived from a metastatic tumour and the hypothesis that BICR-10 was derived from a dysplasia. Furthermore, this pilot study enabled the suggestion of some genetic and epigenetic alterations that cells suffer after radiation treatment. Additionally, it also allowed the association of some genetic characteristics that could be related to the differences in radiation response observable in this two cell lines. Taken together all of our results contribute to a better understanding of radiation effects on HNSCC allowing one further step towards the prediction of patients’ outcome, better choice of treatment approaches and ultimately a better quality of life.
Cancro da Cabeça e Pescoço refere-se a um grupo de tumores que aparecem no trato aerodigestivo superior, sendo que o carcinoma das células escamosas da cabeça e pescoço (CCECP) corresponde a mais de 90% de todos os casos de cancro nesta região. Foi considerado o sexto tumor mais maligno em todo o mundo e, apesar de todos os avanços tecnológicos e clínicos, a taxa de sobrevivência a cinco anos não melhorou significativamente nas últimas décadas. Atualmente sabe-se que o CCECP é uma doença bastante heterogénea que se desenvolve devido à acumulação de alterações genéticas e epigenéticas. Alguns dos grandes problemas associados a este tipo de cancro são o diagnóstico em fase tardia da doença e os poucos resultados terapêuticos. Uma das escolhas terapêuticas para o CCECP é a radioterapia, no entanto, esta tem diversos inconvenientes, como a radioresistência adquirida por algumas células tumorais, que se associam a piores prognósticos. Um aumento do conhecimento na área da biologia da radiação é necessário para melhorar esta opção terapêutica, evitando futuros efeitos tóxicos e fornecendo uma melhor qualidade de vida nos anos subsequentes ao tratamento. Desta forma, a identificação de marcadores moleculares associados quer a uma resposta à radioterapia, quer a possíveis alterações celulares após tratamento com radiação, é essencial para melhorar o diagnóstico, taxa de sobrevivência e qualidade de vida destes doentes. Adicionalmente, existe uma grande falha no conhecimento em relação aos efeitos da radiação nas células, como tal, o principal objetivo deste estudo foi o de contribuir para um conhecimento mais alargado do efeito da radiação em doentes com CCECP. Para isso foram utilizadas duas linhas comerciais celulares, HSC-3 (derivada de um tumor metastático da língua) e BICR-10 (derivada de um tumor da mucosa bucal), que foram caracterizadas com recurso a aCGH, MS-MLPA e citogenética convencional. Estas linhas foram submetidas a diferentes doses de radiação e as alterações genéticas e de metilação pós tratamento foram determinadas. Estes resultados demonstraram uma grande variação de resposta à radiação para estas duas linhas celulares, permitindo a conclusão que a linha HSC-3 é mais radiossensível que a linha BICR-10. Tendo isto em mente, procedeu-se a análise da morte celular, ciclo celular e danos no DNA de forma a tentar compreender esta diferença. A caracterização genética de ambas as linhas celulares permitiu corroborar que a linha HSC-3 era derivada de um tumor metastático e sugeriu que a linha celular BICR-10 estaria associada a um estado de displasia. Para além disto, foi possível analisar alterações genéticas e epigenéticas ocorridas após irradiação e associar determinados perfis genéticos a uma melhor ou pior resposta à radiação. Em suma, os nossos resultados contribuiram para um conhecimento mais aprofundado dos efeitos da radiação no CCECP possibilitando, no futuro, melhores opções de tratamento e uma melhor qualidade de vida para estes doentes.
28
Isenring, Elisabeth A. "The impact of nutrition support in oncology outpatients receiving radiotherapy to the gastrointestinal or head and neck area." Thesis, Queensland University of Technology, 2003. https://eprints.qut.edu.au/36795/1/36795_Digitised%20Thesis.pdf.
Повний текст джерелаАнотація:
Background
Malnutrition occurs frequently in patients with cancer of the gastrointestinal (GI) or head and neck area. This can negatively impact on response to therapy, duration and quality of life (QoL) and health-care costs. The lack of formal systems in oncology outpatient settings means that patients at risk of malnutrition, especially those who are obese or within the healthy-weight range, may be overlooked.
The majority of studies investigating nutrition support in the oncology setting have focused on the impact of enteral or parenteral nutrition. Effects on patient outcomes were mixed. However, inappropriate study designs and goals of nutrition support, or inadequate nutrition support and follow up may have ameliorated these effects. Outcomes which were investigated have often focused on single biochemical and clinical issues and have overlooked the service delivery and more qualitative aspects of care such as, QoL and patient satisfaction.
The aim of this study was to determine the impact of early and intensive nutrition support on a range of outcomes including nutritional status, body composition and QoL compared to usual practice in oncology outpatients receiving radiotherapy to the GI or head and neck area.
Methods
A prospective, randomised-controlled trial was conducted. All outpatients commencing at least five weeks of radiotherapy to the GI or head and neck area at a private Australian radiation-oncology facility during a 12-month period were eligible for inclusion. Persons were deemed ineligible if they were: under the age of 18 years; hospital inpatients for greater than five days; receiving enteral or parenteral nutrition; or not able to provide informed consent.
Outcome parameters were measured at baseline and four, eight, and twelve weeks after commencing radiotherapy treatment. Wherever possible valid and reliable outcome measures were used. Other measures were developed and trialled. Nutritional status was measured using Subjective Global Assessment and the scored Patient-Generated-Subjective Global Assessment (PG-SGA) questionnaire. QoL was measured by the European Organisation for the Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire, version 3. Patient satisfaction was measured with the Patient Satisfaction with Nutrition Services questionnaire within 10 days of completing the 12-week study. Body composition (fat-free mass) was assessed using foot-to-foot bioelectrical impedance analysis (BIA). Foot-to-foot BIA was validated using a deuterium oxide dilution technique and was found to be acceptable at the group level. Bowel health was measured using the Bowel Health Assessment Scale (BHAS) which was developed as part of this study and found to have acceptable reliability and construct validity. Body weight, body mass index, percentage weight loss in the previous six months, diagnosis, treatment, professional field notes collecting qualitative data, and nutrition prescriptions were also recorded.
Analysis
All analyses were performed on an intention to treat basis. Repeated measures analyses were carried out for changes in weight, nutritional status and QoL using SPSS for windows (version 10). Greater than 10 percent of the data were missing for fat-free mass and so repeated measures using a different mathematical modelling approach was carried out using SUDAAN (version 7.5.2A). This is a generalised estimating equations approach which permits the inclusion of subjects with incomplete data records. BHAS was not normally distributed ie Mann-Whitney rank tests were used to compare scores for the two groups across time-points and Fisher's exact tests were performed to determine differences in proportions of those maintaining or improving bowel health between timepoints. Independent T-tests were used to compare mean patient satisfaction scores between the two groups. Statistical significance was reported at the conventional p < 0.05 level (two-tailed).
Results
Seventy-eight consecutive patients undergoing radiotherapy to the GI or head and neck area were eligible for inclusion. Sixty patients (51M;9F; mean age 61.9 yr± 14.0) were emolled and randomised to receive either nutrition intervention (NI; n=29) in the form of regular and intensive nutrition counselling by a dietitian and 3provision of nutrition supplements if appropriate, or usual care (UC; n=31). Six subjects were lost to follow up. There were no significant differences in baseline characteristics between the two study groups.
The NI group maintained weight over 12 weeks (mean change= -0.4kg) compared with those receiving UC who had a significantly greater deterioration in weight (mean change= -4.7kg) (F (1.8)= 10.00; p < 0.001). Changes in fat-free mass over time were clinically significant with the NI group resulting in a mean gain of 0.5kg and the UC group a mean loss of l.4kg fat-free mass over 12 weeks, but this difference did not reach statistical significance (Wald F c3) = 1.62; p = 0.195). Those receiving NI had a significantly smaller deterioration in nutritional status as measured by PG-SGA score and recovered faster than those receiving UC (Fc2.6) = 5.434; p = 0.02). The NI group also had a significantly smaller decrease and faster recovery in QoL over time compared with the UC group (F(3) = 4.03; p = 0.009). The greatest proportion of subjects who maintained or improved their bowel-health status over time were receiving NI and this was significant between baseline and one month (Fisher's exact test; p = 0.004) and two and three months (Fisher's exact test; p = 0.053), but not between one and two months (Fisher's exact test; p = 0.456). Subjects receiving NI were significantly more satisfied with nutrition services than those receiving UC (F51)= 13.88; p = 0.002).
Conclusions
In conclusion, results of this study suggest that early and intensive nutrition support provides beneficial outcomes in terms of minimising weight loss and deterioration in nutritional status, QoL and bowel health in oncology outpatients receiving radiotherapy to the GI or head and neck area. Weight maintenance in this population leads to beneficial outcomes and suggests that this, rather than weight gain, may be a more appropriate aim of nutrition support. Patients receiving NI were more satisfied with services than those receiving UC. Further studies are required to determine which patients respond positively to NI and the form of NI that leads to the greatest benefits.
29
Kawamura, Mitsue. "A scoring system predicting acute radiation dermatitis in patients with head and neck cancer treated with intensity-modulated radiotherapy." Kyoto University, 2019. http://hdl.handle.net/2433/244519.
Повний текст джерела
30
Zziwa, Aloysious. "A RADIOTHERAPY PLAN SELECTOR USING CASE-BASED REASONING." Master's thesis, Temple University Libraries, 2010. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/85055.
Повний текст джерелаАнотація:
Electrical EngineeringM.S.E.
Developing a head and neck cancer treatment plan for a candidate of Intensity Modulated Radiation Therapy (IMRT) requires extensive domain knowledge and subjective experience. Therefore, it takes a cancer treatment team at least 2 to 3 days to develop such a plan from scratch. Many times the team may not use a reference plan. Sometimes, to reduce the amount of time taken to generate each treatment plan, these experts recall a patient, whose plan they recently prepared, and who had similar symptoms as the candidate. Using this recalled patient's plan as the starting point, the cancer treatment team modifies it based on the differences in the symptoms of the new candidate and those of the reference patient record. The resultant plan after modification is presented as the new treatment plan for the oncologist to evaluate its suitability for treatment of the candidate. This approach is heavily dependent on the team's choice of the reference patient record. Choosing a starting treatment plan where the patient's symptoms are not the closest to the new candidate implies that more time will be spent modifying the plan than is necessary and the resultant treatment plan may not be the best achievable under the same circumstances given a better starting plan. Therefore, the team's bias in choosing the starting plan may affect the quality of treatment plan that is finally produced for the candidate. This thesis proposes a system that behaves like an un-biased radiotherapy expert - following a similar process and standards as the human experts and which searches the entire IMRT patient database and returns the record (with patient symptoms and treatment plan) for a patient whose symptoms are most similar to the candidate's symptoms. It takes in the new candidate's information (from diagnosis, scans of the tumor and interviews with the candidate), searches the database and prints out a patient record showing another patient's treatment plan as the suggested starting point for generating the new plan. The system uses Case-Based Reasoning (CBR) because it mimics the experts' approach since it makes use of previous successes and shuns reasoning that has failed in the past. This occurs by considering only treatment plans that have been implemented successfully on patients in the hospital archive. For this thesis, CBR is applied using fuzzy IF-THEN rules to search the patient database. Fuzzy logic is used because it can handle imprecise expressions commonly used in natural language to determine the appropriate weight of the patient attributes in the search process. Filtering of patient records based on parameter value ranges is also used to reduce the number of records that have to be compared. The system code developed for this thesis was prepared in Java and C Language Integrated Production System (CLIPS) using the Java Expert System Shell (JESS). This system is part of a bigger expert system that is being prepared by the Intelligent Systems Applications Center (ISAC) for Thomas Jefferson University Hospital, expected to generate a radiotherapy plan for a patient designated for IMRT treatment. Initial results from the developed prototype prove the viability of selecting similar patients using CBR. It is important to note that the overall objective of the project is to build a system that effectively aids decision support by the IMRT team when generating a new treatment plan and not to replace them. The team is expected to use the generated plan as a starting point in determining a new treatment plan. If the generated plan is sufficient, the oncologist and their team will have to check this plan (in their various capacities) against expected standards for quality control before passing it on for implementation. This will save them time in planning and allow them to focus more on the patient's needs hence a higher quality of life for the patient after treatment.
Temple University--Theses
31
Helal, Azza Mahmoud. "The effect of patient anatomy on optimised intensity modulated radiotherapy dose distributions for head and neck and prostate cancer." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438639.
Повний текст джерела
32
Zheng, Xiangpeng. "Specificity and feasibility of HN-5 peptide for diagnosis and targeted therapy of head and neck squamous cell carcinomas : a dissertation /." San Antonio : UTHSC, 2007. http://proquest.umi.com/pqdweb?did=1400957411&sid=1&Fmt=2&clientId=70986&RQT=309&VName=PQD.
Повний текст джерела
33
Gulati, Shuchi. "Phase-1 Study of Metformin in Combination with Concurrent Cisplatin and Radiotherapy in Patients with Locally Advanced Head and Neck Cancer." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1593171585877322.
Повний текст джерела
34
Lochner, Johann Georg. "A comparison of two saliva substitutes in the management of xerostomia during radiotherapy for cancer of the head and neck." Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_9540_1257166768.
Повний текст джерелаАнотація:
The aim of the study is to compare the palliative efficacy of two saliva substitutes (Sinspeek and Xerostom) in patients during radiotherapy for cancer of the head and neck. This crossover randomised controlled clinical trial was carried out on twenty-five patients with malignant tumours of the head and neck, following four weeks of radiotherapy at tygerberg hospital. The benefit of saliva substitutes to ameliorate the effects of xerostomia is well established and proper advice and access to relevant preparations is essential.
35
Marcu, Loredana Gabriela. "Deterministic modelling of kinetics and radiobiology of radiation-cisplatin interaction in the treatment of head and neck cancers." Title page, contents and abstract only, 2004. http://hdl.handle.net/2440/37961.
Повний текст джерелаАнотація:
One of the main objectives of combining radiation treatment and chemotherapy is to obtain a therapeutic gain by an improved tumour control with less or no enhancement of normal tissue toxicity. The optimal schedule for the combined treatment of cisplatin-radiation is still under investigation. Neither the optimal time interval, nor the most adequate sequence of administration of cisplatin and radiation are known. The results of the trials are also inconclusive. Some trials showed a supra-additive effect from the administration of cisplatin before radiotherapy, others, on contrary, from the injection of drug after radiotherapy. The present work encompasses the major challenges brought by the combined modality treatment: cisplatin-radiotherapy. The major goal of this work was to investigate the optimal treatment sequencing between cisplatin and radiotherapy and also the optimal schedule for head and neck carcinomas. Therefore, a computer-based tumour model with literature-given biological parameters has been developed which has allowed the simulation of treatment with radiation and chemotherapy. Radiotherapy has been simulated on the virtual tumour and the effects of radiotherapy on tumour regression and regrowth have been analyzed. Also, the mechanisms of cisplatin's action on tumour have been implemented, and the phenomena of drug resistance and tumour repopulation during chemotherapy studied. Finally, the combined modality treatment has been simulated, and the effect of drug-radiation interaction on tumour behaviour evaluated. The current investigation has shown that cisplatin administered immediately before radiation gives similar tumour control to the post-radiation sequencing of the drug. Furthermore, the killing effect of the combined modality treatment on tumour increases with the increase in cell recruitment. The individual cell kill produced by cisplatin and radiation leads to an additive-only tumour response when the treatments are given concurrently, and for a synergistic effect cisplatin must potentiate the effect of radiation. The final conclusion, by which cisplatin administered on a daily basis leads to a better tumour control than cisplatin administered weekly, is in accordance with the latest trial results on head and neck cancers. Therefore, treatment regimens that correlate better with the pharmacokinetics and the radiobiological properties of the therapeutic agents result in better outcomes.Thesis (Ph.D.)--School of Chemistry and Physics, 2004.
36
Satherley, Thomas William Scott. "The impact of plan complexity on the accuracy of VMAT for the treatment of head and neck cancer." Thesis, University of Canterbury. Physics, 2015. http://hdl.handle.net/10092/10584.
Повний текст джерелаАнотація:
Purpose: At the Wellington Blood and Cancer Centre (WBCC), Volumetric Modulated Arc Therapy (VMAT) is used to treat a variety of head and neck (H&N) cancers. Presently, the complexity of plans is limited to ensure the accuracy of patient treatment within the range of the departmental experience. The complexity limitation is applied through use of a monitor unit (MU) constraint during plan optimisation. Plans of higher complexity can be obtained by loosening the MU constraint, and setting more stringent optimisation objectives on organs at risk (OAR) and target volumes (PTV). This could potentially yield higher quality treatment plans but may also degrade the accuracy of the TPS calculation or the plan delivery at the treatment machine. The aim of this study is to investigate the level of plan complexity that results in accurate treatment plan calculation and delivery, and quantify the corresponding gain in plan quality.
Methods: Five previously treated H&N patients were selected for the study. Each patient’s clinical plan was used as the lowest complexity level and labelled C1. Subsequently, an approximate pareto-optimal plan (C3) was created that focused equally on sparing spinal cord, brain stem and parotid gland while maintaining, or improving on, the previously obtained target coverage. Next, a C2 plan was created such that the plan quality was in between C1 and C3. Plan quality of each complexity level was assessed in terms of OAR sparing and PTV coverage. The average leaf pair opening (LPO), critical leaf pair opening (%LPO<1cm) and mean leaf travel were used as plan complexity metrics.
The calculation and delivery accuracy of each complexity level using Varian TrueBeam LINAC/Eclipse TPS was verified using time resolved point dose measurements (TRPD), EBT film measurements (Ashland Inc.) and ArcCheck measurements (Sun Nuclear Corp.). A comprehensive uncertainty analysis was carried out including a quantification of the measurement and delivery reproducibility.
Results: Increasing plan complexity from C1 to C3 reduced the Spinal Cord D1cc, Brain Stem D1 and Parotid Gland Dmean up to 14.7 Gy, 7.1 Gy and 7.8 Gy, respectively. In addition, C3 plans improved the target coverage compared to C1 plans, with the PTV66 and PTV54 D98 increasing up to 1.0 Gy and 0.6 Gy, respectively. The verification measurements showed that the plan calculation and delivery for all complexity levels was well within clinical acceptance levels (Table 1). TRPD showed that VMAT dose delivery itself was repeatable within 0.1% (1 S.D.) over 10 consecutive deliveries for both C1 and C3 complexity levels.
Discussion & Conclusions: This study has shown that increasing the plan complexity can provide significant dosimetric advantages for the treatment of H&N cancer. Verification measurement results indicated that this did not noticeably degrade the calculation and delivery accuracy of VMAT using a Varian TrueBeam LINAC and our Eclipse TPS beam model. H&N VMAT at the WBCC can now be developed further with greater confidence in the dosimetric accuracy of higher complexity plans.
37
POLI, MARIA E. R. "Definição do volume de planejamento do alvo (PTV) e seu efeito na radioterapia." reponame:Repositório Institucional do IPEN, 2007. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11552.
Повний текст джерелаАнотація:
Made available in DSpace on 2014-10-09T12:53:10Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T13:58:56Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
38
Larsson, Maria. "Eating problems in patients with head and neck cancer treated with radiotherapy : Needs, problems and support during the trajectory of care." Doctoral thesis, Karlstad University, Faculty of Social and Life Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-777.
Повний текст джерелаАнотація:
Aim: The overall aim of this thesis was to acquire knowledge about daily life with focus on eating problems during the trajectory of care for patients with head and neck cancer treated with radiotherapy. Method: The data in study I were gained from medical and nursing records of 50 patients. Documented parameters of eating problems, their causes and consequences, and undertaken interventions were collected before treatment, during radiotherapy, and one, six, and twelve months after completion of treatment, using a study-specific audit instrument. Data were analysed with descriptive and inferential non-parametric statistics. In study II eight patients were interviewed during the radiotherapy treatment period with focus on experiences of eating problems. In study III nine patients were interviewed six to twelve weeks after treatment with the focus on experiences of daily life during the trajectory of care having eating problems. In study IV twelve patients were interviewed about their conceptions of the significance of a supportive nursing care clinic during the whole trajectory of care. Data were analysed with interpretative phenomenology (II, III) and phenomenography (IV). Findings: The four studies showed that being a patient in the trajectory of care often meant that life was disturbed and threatened. This was partly due to the eating problems and their consequences, which could occur during the whole trajectory of care (I, III, IV) but was experienced as most intense and severe during radiotherapy (II) and the nearest weeks after completion of radiotherapy (III, IV). The disturbances and threats experienced due to eating problems could affect the whole person as they were physical (I-IV), psychological, social and existential (II, III). The experiences of eating problems due to the tumour and its treatment and the experience of having cancer per se were strongly connected as one phenomenon, which disturbed and threatened the informants’ daily life. The other part that disturbed the patients’ life was the waiting in suspense. A long and trying waiting in uncertainty was experienced due to lack of knowledge and support, practical as well as emotional. This was most pronounced during pauses in radiotherapy (III) and after completion of the treatment when the lack of support from the health care was obvious (I, II, III). The patients were then most often left to their own devices. In order to endure, they needed both inner strength, described as own coping strategies, and strength from outside, described as support from family, friends and health care professionals (II, III). The nurse clinic was found to give a hand to hold during the whole trajectory of care (IV). It could meet these patients’ needs of knowledge, care and support, both concerning practical measures related to the eating problems and other side-effects of the treatment, and concerning their emotional needs. In addition the nurse clinic could support the relatives in their worries and anxiety (IV). Conclusion: This thesis showed the necessity of continuous assessment, treatment and evaluation of patients’ problems, and the patients’ needs of information and support throughout the trajectory of care.
39
Nutting, Christopher. "Can intensity-modulated radiotherapy (IMRT) be used to reduce toxicity and improve tumour control in patients with head and neck cancer?" Thesis, City University London, 2012. http://openaccess.city.ac.uk/1128/.
Повний текст джерелаАнотація:
Radiotherapy is commonly used in the treatment of head and neck cancer. For early stage tumours, conventional radiotherapy techniques have a high cure rate and low levels of long-term complications. Patients with more advanced cancers have much lower cure rates and high levels of treatment-related complications. Intensity modulated radiotherapy (IMRT) is a new form of focussed radiation therapy. It has been used to reduce the radiation dose to normal tissue structures and increase the dose delivered to tumour bearing tissues. This potentially allows reduced side effects and increased tumour control compared to conventional radiotherapy. The rationale of this thesis was to test whether these twin goals could be achieved in head and neck cancer patients. The first part of the thesis describes improvements in patient immobilisation, optimisation of techniques for neck irradiation, and evaluation of the technique in a busy radiotherapy department. It includes pre-clinical evaluation of IMRT for different tumour sites, the development of quality assurance programs and the conduct of a national randomised controlled trial of parotid-sparing IMRT. This trial concluded that IMRT significantly reduced patient-reported xerostomia, allowed recovery of saliva production and improved quality of life. The second part of the thesis describes pre-clinical evaluation of techniques to escalate radiation dose in patients with larynx and hypopharynx tumours. A phase I/II clinical trial showed that higher doses of radiation can be delivered at the expense of an increase in acute radiation toxicity but without a measurable increase in late radiation side effects. In the larynx and hypopharynx groups, a possible increase in local control was observed. This thesis describes the process of evaluation of a new radiotherapy technology and could be used as a template for testing other new technologies in the future.
40
Wegoye, Emmanuel. "Radiotherapy for head and neck paragangliomas: A 10 year retrospective review 2005-2014 at Groote Schuur Hospital and UCT Private academic hospital." Master's thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/30840.
Повний текст джерелаАнотація:
Objective. Over the last two decades there has been increasing evidence that radiosurgery and radiotherapy management of skull-base paragangliomas is as effective as microsurgical resection and carries less morbidity. This 10 year retrospective review of 24 patients in a single institution, treated over 10 years assesses tumour control rates and morbidity associated with radiosurgery and radiotherapy treatment. Method. Patients with a radiological diagnosis of skull-base paragangliomas were treated with different techniques of stereotactic and image-guided radiotherapy delivering hypo fractionated irradiation. Techniques used included conventional radiotherapy or intensity modulated radiotherapy (IMRT), dynamic arc (DA) and volumetric modulated arc therapy (VMAT). Analysis of local tumour control was performed using RECIST criteria and the KaplanMeier method. 69% of patients received 14-16gy in 1-3 fractions while 31% received 48- 50gy in 25 fractions. Radiation-associated toxicity was graded according to the commonly used Radiation therapy Oncology group (RTOG) toxicity criteria. Results. 24 patients with skull-base paragangliomas were treated with a median follow up of 43 months. One patient lost to follow up and was excluded. Tumour control was achieved in 96% of patients. 76% of patients treated reported no radiation associated toxicity. 24% of patients had some radiation associated toxicity: the conventional group 12%, stereotactic radiosurgery 8% and stereotactic radiotherapy 4%. 43% of patients in the conventional group had progression of hearing loss in the affected ear. One patient in the radiosurgery group developed osteonecrosis of the temporal bone at 5 year follow up. Conclusion. Radiosurgery and radiotherapy are efficacious in achieving tumour control with minimal morbidity. Tumour control rates in the study are similar to control rates in literature. Radiation associated toxicities are mainly minor. Study is limited by the retrospective nature and limited duration of follow up.
41
De, Pomeroy-Legg Jeanita. "Prevalence of side-effects and change in nutritional status during radical radiotherapy for head and neck malignancies at Tygerberg Academic Hospital, Western Cape, South Africa." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1492.
Повний текст джерела
42
Blades, Rae. "A cost-effectiveness analysis of a silicone film-forming gel versus 10% glycerine in patients with head and neck cancer." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/198193/1/Rae_Blades_Thesis.pdf.
Повний текст джерелаАнотація:
Radiation dermatitis is one of the most common and difficult to manage side effects for patients with head and neck cancer undergoing radiotherapy. This thesis involved a trial based economic evaluation of a silicone gel (StrataXRT®) versus 10% Glycerine (Sorbolene) in the management of radiation dermatitis in patients with head and neck cancer. The study highlighted the importance of undertaking robust economic evaluations to inform health service managers' decision making about resource use. The use of silicone and other gels remains a promising area for future research.
43
Conibear, John Richard. "Assessment of target volume and organ at risk contouring variability within the context of UK head and neck and lung cancer radiotherapy clinical trials." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10045105/.
Повний текст джерелаАнотація:
AIMS: Radiotherapy quality assurance (RTQA) is now a requirement of radiotherapy trials since poor target volume and organ at risk (OAR) contouring has been shown to impact on patient outcomes within the context of clinical trials. The first hypothesis for this research is that statistically significant inter-observer variation exists amongst clinical oncologists’ target volume and OAR contours within the context of the pre-trial quality assurance (QA) benchmark cases for four different UK radiotherapy trials. The second hypothesis is directed towards confirming that RTQA feedback during the pre-trial benchmark period does influence contouring for head and neck cancers. MATERIALS/METHODS: Four radiotherapy trials (ART-DECO, COSTAR, IDEAL and i-START trials) that require all prospective investigators to submit pre-accrual benchmark cases were selected. All benchmark cases until November 2012 were collected in DICOM format. The investigator contours were grouped into either target contours (TARGET) i.e. CTV1, parallel OARs (OAR-P) i.e. parotid glands, lungs and heart or serial OARs (OAR-S) i.e. brainstem, spinal cord and oesophagus. These were then analysed using a tumour management group (TMG) consensus contour to determine whether statistically significant differences existed between them. The local conformity index (L-CI) for each structure was also calculated for analysis. RESULTS: Analysis of the pre-trial benchmark cases revealed statistically significant differences (p= < 0.05) between clinical oncologists’ target volume, serial and parallel OAR contours. Analysis of the resubmitted head and neck pre-trial benchmark cases also revealed statistically significant differences between first and subsequent submission contours. CONCLUSIONS: This research revealed that a statistically significant difference does exist in clinical oncologists’ target volume and OAR contours within the pre-trial QA benchmark cases for both lung and head and neck cancers. It was also revealed that RTQA feedback during the pre-trial benchmark period had a positive and statistically significant impact on head and neck clinician contouring.
44
Georgi, Alexander. "Lokal fortgeschrittene Kopf-Hals-Tumoren- Eine retrospektive, monoinstitutionale Studie zur Beurteilung der postoperativen Radiochemotherapie im klinischen Alltag." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-130129.
Повний текст джерелаАнотація:
Die vorliegende retrospektive Studie zur postoperativen Radiochemothera-pie bei fortgeschrittenen Kopf-Hals-Tumoren sollte die eigenen Ergebnisse mit den prospektiv-randomisierten Studien vergleichend darlegen und dabei den Nutzen einer Radiochemotherapie überprüfen. Insgesamt wurden 155 Patienten in der retrospektiven Analyse eingeschlossen. Die Überlebens- und Rezidivraten des Patientengutes konnten anlehnend zu den publizier-ten Studien reproduziert werden. Ein Vorteil der Radiochemotherapie in Bezug nehmend auf den posttherapeutischen Verlauf konnte hierbei nicht festgestellt werden. Es traten signifikant vermehrt höhergradige Akutne-benwirkungen nach Applizierung der simultanen, systemischen Therapie auf. Die Arbeit konnte zeigen, dass sich durch die Reduzierung der Gesamt-behandungszeit als auch des Intervalls zwischen Operation und Beginn der adjuvanten Therapie das Gesamtüberleben sowie die lokoregionäre Rezidiv-rate signifikant verbessern ließen. Insgesamt scheinen die Fernmetastasie-rungen und die lokoregionären Rezidive maßgebend für die immer noch un-befriedigenden Überlebensraten zu sein. Gegenstand weiterer Untersu-chungen sollte daher die Optimierung der prätherapeutischen Diagnostik sowie der adjuvanten Therapie sein.
45
Albuquerque, Danielle Frota de. "Avaliação dos parâmetros de halitose e sialometria em pacientes submetidos à radioterapia de cabeça e pescoço." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/25/25132/tde-14062007-132546/.
Повний текст джерелаАнотація:
O objetivo deste estudo foi investigar as relações entre os parâmetros de halitose e sialometria em pacientes submetidos à radioterapia de cabeça e pescoço, avaliando a presença de saburra, classificada em termos de peso seco, fluxo salivar, teste BANA e halimetria oral e comparar os resultados entre os grupos. Foram examinados 48 pacientes divididos em três grupos. O grupo 1 (\"saúde\") foi constituído de pacientes que haviam terminado o tratamento na Faculdade de Odontologia de Bauru (FOB), sem queixa de halitose e com íntegra saúde oral; o grupo 2 (\"N. O.\") por indivíduos com necessidades odontológicas e o grupo 3 (\"radio\") pacientes que haviam sido submetidos à radioterapia na região de cabeça e pescoço. Foram avaliadas as concentrações bucal de Compostos Sulfurados Voláteis (CSVs) através do monitor portátil de sulfetos HalimeterTM, os valores relacionados à taxa de fluxo salivar em repouso e estimulado, teste BANA com material proveniente da saburra lingual e peso seco da mesma. Os resultados foram analisados utilizando o teste de análise de variância que quantificaram o hálito antes e após a remoção da saburra. As relações entre halimetria bucal, peso seco da saburra, fluxo salivar com e sem estímulo, e a relação entre fluxo salivar em repouso e estimulado foram feitas através do teste de correlação de Pearson. Para verificar correlações entre halimetria bucal inicial e teste BANATM foi utilizado o teste \"t\" de Student. Os resultados mostraram que houve diferença estatisticamente significante entre a halimetria oral nos grupo \"saúde\" e \"radio\" e, nos grupos \"saúde\" e \"N.O.\" Pode-se observar também que houve relação entre a presença de saburra e os níveis de CSVs. Em relação ao fluxo salivar, foi observada uma redução estatisticamente significante entre o grupo \"radio\" e os outros dois. Nas condições dessa pesquisa, foi constatado que a halitose pode ser considerada um efeito adverso da radioterapia, vinculada à hipossalivação e saúde oral deficiente.The aim of this study was to verify the halitosis parameters in patients who had received head and neck radiotherapy. The degree of halitosis was determined through the presence of tongue coating, classified according to its dry weight; the salivary flow rate, the BANATM test and HalimeterTM oral measurements. A total of 48 subjects were examined, which were divided into three groups. Group 1 was consisted for patients with good oral health and no complains of bad breath; Group 2 consisted of patients with bad oral health condition and Group 3 comprised individuals who had received head and neck radiotherapy. The concentration of Volatile Sulfur Compounds (VSC) was assessed by means of a portable sulfide monitor (HalimeterTM) and the values were correlated to the resting and stimulated salivary flow rate and to the BANATM test with material collected from the tongue coating and its dry weight. Halitosis was quantified before and after the removal of the tongue coating and the data was analyzed by means of the ANOVA test. The correlation among salivary flow rate, weight of the tongue coating and HalimeterTM oral measurements was evaluated by the Pearson test. The results showed a statistically significant difference between group 1 and 3, and between groups 1 and 2. A relationship between the presence of tongue coating and the VSC levels was also demonstrated. In concerning to the salivary flow rate, there was a statistically significant reduction between group 1 and 3, and group 2 and 3. In the accordance of this study, halitosis can be considered a side effect of radiotherapy, tied with the hyposalivation and deficient oral health.
46
Alencar, Anelise Ribeiro Peixoto. "Tratamento da mucosite oral radio e quimioinduzida: comparação entre protocolo medicamentoso convencional e tratamentos com lasers em baixa intensidade." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-01072011-131133/.
Повний текст джерелаАнотація:
Neste estudo clínico verificaram-se os efeitos do laser em baixa intensidade na prevenção e tratamento da mucosite oral radio e/ou radioquimioinduzida. Foram selecionados 31 pacientes portadores de câncer em cabeça e pescoço a serem submetidos à radioterapia ou a radioterapia em associação a quimioterapia, os quais foram distribuídos aleatoriamente em três grupos: grupo 1 (controle) tratamento medicamentoso; grupo 2 tratamento medicamentoso e laserterapia diária, a partir do início da ulceração referente à mucosite grau 2 e grupo 3 tratamento medicamentoso e laserterapia diária a ser iniciada imediatamente antes do início da radioterapia. Os parâmetros de irradiação foram: comprimento de onda de 660nm, potência de 100mW, modo de operação contínuo, aplicação pontual, energia de 2J por ponto em 30 pontos pré-determinados, sendo o tempo utilizado de 20s por ponto. O grupo controle recebeu tratamento medicamentoso que consistia no uso de um conjunto de medidas preventivas e terapêuticas para abordagem dos efeitos adversos agudos radioinduzidos. Os resultados foram avaliados, quanto à ocorrência, graus e escore de dor associados à mucosite oral, perda de massa corpórea, uso de sonda nasogástrica, necessidade de internação e interrupção do tratamento oncológico decorrentes da mucosite oral. Os resultados indicam que o protocolo de aplicação do laser em sua forma preventiva é o mais efetivo na prevenção e tratamento da mucosite oral e que seu uso diário contribuiu para o alívio da sintomatologia dolorosa colaborando para melhora da qualidade de vida do paciente oncológico.In this clinical study verified the effects of low intensity laser in the prevention and treatment of oral mucositis radio and/or chemical induced. Thirty one patients with head and neck cancer were selected before being submitted to cancer exclusive radiotherapy or radio and associated chemotherapy. The patients were distributed into three randomly groups as follows: group 1- (control) conventional medicine treatment; group 2 conventional medicine treatment and daily lasertherapy as soon as grade two oral mucositis appeared; group 3 conventional medicine treatment and daily lasertherapy to be initiated immediately before radiotherapy sessions.The irradiation parameters were: wavelength of 660nm, potency of 100mW, continuous mode, punctual application, 2J energy on thirty pre-determined 30 points, with 20s of exposure per point. The control group received medical treatment which consisted in using a set of preventive and therapeutic approach for acute radiation-induced adverse effects. Results were evaluated observing occurrence and grade of oral mucositis, score of pain, loss of body mass, use of nasogastric sound line, internment and interruption of oncologic treatment due to oral mucositis. The results showed that the preventive protocol as used was the most effective in prevention and treatment of oral mucositis and that its daily application contributed in relieving the painful symptomatology so collaborating to maintain and/or bettering the life quality of oncologic patients.
47
Silva, Ana Margarida Abreu Rodrigues da. "A radioterapia em patologia oncológica de cabeça e pescoço: impacto na qualidade de vida e na saúde oral." Master's thesis, [s.n.], 2012. http://hdl.handle.net/10284/3407.
Повний текст джерелаАнотація:
Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina DentáriaO cancro é um problema de saúde pública a nível mundial, devido à sua crescente prevalência, com grande impacto individual e social. Têm-se verificado progressos importantes no tratamento oncológico, aumentando a expectativa de vida dos doentes, pelo que é de extrema importância para a sua recuperação e reintegração na sociedade, melhorar a Qualidade de Vida Relacionada com a Saúde (QdVRS) dos mesmos. A radioterapia é uma das modalidades terapêuticas mais utilizadas no tratamento do patologia oncológica de cabeça e pescoço, podendo estar associada ou não à cirurgia ou quimioterapia. No entanto, apesar do tratamento radioterápico visar atingir apenas as células neoplásicas, pode provocar efeitos secundários nocivos nas células normais da zona irradiada, interferindo na QdVRS do doente ou mesmo alterando a evolução do próprio tratamento. Algumas das complicações mais frequentes da radioterapia na cavidade oral são a xerostomia, mucosite, disfagia, candidose, entre outras. Assim, o Médico Dentista tem um papel fundamental na equipa multidisciplinar de tratamento oncológico, permitindo minimizar a frequência e morbilidade das complicações decorrentes da doença ou do seu tratamento e, consequentemente, melhorar a QdVRS destes doentes. Neste estudo pretende-se avaliar o impacto do tratamento radioterápico na QdVRS dos doentes oncológicos de cabeça e pescoço. Para isso, 91 doentes oncológicos de cabeça e pescoço do Instituto Português de Oncologia Francisco Gentil do Porto (IPOPFG) responderam a dois questionários diferentes sobre QdVRS: EORTC QLQ-C30 (avaliação geral da QdVRS) e QLQ-H&N35 (módulo específico para pacientes com patologia oncológica de cabeça e pescoço). Os resultados obtidos indicam que aquando do diagnóstico, a maioria dos tumores encontra-se em estádios avançados da doença (58.5%), sendo a QdVRS dos homens mais afectada comparativamente à das mulheres. Conclui-se que é de extrema importância a sensibilização da população para o cancro oral e a necessidade de exames de rotina da cavidade oral de modo a permitir o diagnóstico precoce da doença. Due to its increasing prevalence cancer is a public health problem worldwide with huge individual and social impact. There have been significant advances in cancer treatment, increasing patients’ life expectancy. Thus it is of utmost importance to their recovery and reintegration into society to improve patients’ Health-Related Quality of Life (HRQoL). Radiation therapy is one of the most used therapies in the treatment of the head and neck cancer, and may be used together with surgery or chemotherapy. However, despite aiming at targeting only the neoplastic cells, it can cause harmful side effects in normal cells of the radiated area, interfering in the patient's HRQoL or even changing the evolution of the treatment itself. Some of the most frequent complications of radiotherapy in the oral cavity are xerostomy, mucositis, dysphagia, candidiasis, among others. So, the Dentist has a fundamental role in the multidisciplinary team of oncological treatment, minimizing the frequency and morbidity of the complications arising from the disease or its treatment and, consequently, improving the HRQoL of these patients. This study aims to evaluate the impact of radiation treatment on the HRQoL of patients with head and neck cancer. To do this, 91 patients with head and neck cancer being treated at Instituto Português de Oncologia Francisco Gentil (Portuguese Institute of Oncology Francisco Gentil - IPOPFG), in Porto, answered to two different questionnaires on HRQoL: EORTC QLQ-C30 (general assessment of HRQoL) and QLQ-H&N35 (specific module given to patients with head and neck cancer). The results obtained indicate that at the time of diagnosis, most tumors are in advanced stages of the disease (58.5%), the HRQoL of men being more affected when compared to that of women. It is concluded that it is of utmost importance the awareness of the population to oral cancer and the need for routine examinations of the oral cavity to allow for early diagnosis of the disease.
48
Duma, Marciana Nona [Verfasser], Hans C. W. E. [Akademischer Betreuer] Geinitz, Jürgen [Akademischer Betreuer] Debus, and Michael [Akademischer Betreuer] Molls. "The impact of image guided radiotherapy in head and neck cancers:soft tissue changes, dosimetric consequences and adaptive radiotherapy / Marciana-Nona Duma. Gutachter: Jürgen Debus ; Hans C.-W. E. Geinitz ; Michael Molls. Betreuer: Hans C.-W. E. Geinitz." München : Universitätsbibliothek der TU München, 2012. http://d-nb.info/103151211X/34.
Повний текст джерела
49
ALENCAR, ANELISE R. P. "Tratamento da mucosite oral radio e quimioinduzida: comparacao entre protocolo medicamentoso convencional e tratamentos com lasers em baixa intensidade." reponame:Repositório Institucional do IPEN, 2011. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9632.
Повний текст джерелаАнотація:
Made available in DSpace on 2014-10-09T12:28:54Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T13:57:01Z (GMT). No. of bitstreams: 0
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
50
Chan, King Chong. "Jaw Bone Changes on Panoramic Imaging after Head and Neck Radiotherapy." Thesis, 2012. http://hdl.handle.net/1807/33363.
Повний текст джерелаАнотація:
Gnathic changes after head and neck radiotherapy have not been thoroughly characterized radiographically. The objectives of this study are to characterize changes to the teeth and jaws on panoramic images following intensity modulated radiotherapy (IMRT), and to determine whether subject comorbidities and radiation dose affect these changes. This retrospective analysis reviews the charts and panoramic images of 126 head and neck cancer patients who received IMRT at Princess Margaret Hospital between January 1, 2005 and December 31, 2008. Of the 126 subjects, 75 (60%) showed changes on panoramic radiographs; 66 (88%) of which consisted of widened periodontal ligament spaces (WPLS). The median time to WPLS was 29 months after IMRT. Female sex and dose correlated with decreased time to WPLS. These results suggest that WPLS is a common radiographic sign following IMRT that may not require endodontic intervention as post-IMRT WPLS is unrelated to the pulpal status of the tooth.