Semi-automatic Tracking of the Hyoid bone and the Epiglottis Movements in Digital Videofluoroscopic Images

Swallowing is a process that happens hundreds of times per day during eating, drinking, or swallowing saliva. Dysphagia is an abnormality in any stage of the swallowing process. It can cause serious problems such as dehydration and respiratory infection. In order to help dysphasic patients, radiologists need to evaluate the patient’s swallowing ability, usually using Video Fluoroscopic Swallowing Study (VFSS). During the assessment, several measurements are taken and evaluated, such as the displacement of the hyoid bone and epiglottis. Usually radiologists perform evaluation by means of visual inspection, which is a time consuming process that produces subjective results. Previous research has made strides automating swallowing measurements in order to produce objective results, but there is no study that automatically tracks the movement of the epiglottis. This thesis presents a design and implementation of a Computer Aided Diagnosis (CAD) system that can automatically track the movement of the hyoid bone and the epiglottis using minimal user input. The correlation between these two movements will be studied. With the aid of this system, radiologists can more reliably and efficiently take measurements and evaluate the health of the swallowing process

RAJKIRAN NATARAJAN

Many research questions in dysphagia research require frame-by-frame annotation of anatomical landmarks visible in videofluorographs as part of the research workflow, which can be a tedious and error prone process. Such annotation is done manually using image analysis tools, is error prone, and characterized by poor rater reliability. In this thesis, a computer-assisted workflow that uses a point tracking technique based on the Kanade-Lucas-Tomasi tracker to semi-automate the annotation process, is developed and evaluated. Techniques to semi-automate the annotation process have been explored but none have had their research value demonstrated. To demonstrate the research value of a workflow based on point tracking in enhancing the annotation process, the developed workflow was used to perform an enhanced version of the recently published Coordinate Mapping swallowing study annotation technique to determine several swallowing parameters. Evaluation was done on eight swallow studies obtained from a variety of clinical sources and showed that the workflow produced annotation results with clinically insignificant spatial errors. The workflow has the potential to significantly enhance research processes that require frame-by-frame annotation of anatomical landmarks in videofluorographs as part of their data preparation steps, by reducing the total time required to annotate clinical case

Automatic demarcation for videofluoroscopy swallowing study

Videofluoroscopy tests are designed to analyze the swallowing response of the patient. Lot of patients die due to swallowing disorders, and physicians want to analyze this procedure to detect this swallowing problems. The principal problem is that the time spent to analyze a video is so long, and has to be done manually, and this derives to a high cost of time and money to the health system. Hyoid Marker is an application that provides an automatic demarcation for videofluoroscopy studies, saving to the physician the time to mark important objects in the video, and allowing him to dedicate his time analyzing only the medical aspects of the video

Evaluation of the results of orthodontic treatment by non-rigid image registration and deformation-based morphometry

The goal of this research was to find out, whether the non-rigid registration of dental casts can be used in the evaluation of orthodontic treatment and to develop a program, which would at least partially automatize the evaluation process of images. The aim was also to experiment the evaluation of three-dimensional models of the casts. This research was delimited to cover only the evaluation of malocclusions within the dental arch. The relationships between the dental arches were not considered. This thesis was done in the University of Vaasa at the Department of Electrical Engineering and Energy Technology as a part of the HammasSkanneri research project, whose aim is to automatize the digitization and archiving of dental casts. This research used two-dimensional images of dental casts which were taken of orthodontically treated patients before and after orthodontic treatment. Non-rigid registration was performed by using a registration tool of Fiji software. The evaluation of the accuracy of the registration was performed by measuring distances between manually inserted landmarks, and by comparing the linear and angular parameters of the registered images and the original target images. The displacements of the teeth were approximated with the help of deformation-based morphometry. The accuracy of registration is within reasonable error limits, if the image is taken straight from above of the cast and the registration is performed with the help of landmarks inserted by a human. Estimation of the changes showed that the movement of teeth can be coarsely measured by using deformation-based morphometry based on change estimates that resemble the Jacobian estimates. A set of programs, which partially automatize the evaluation of the accuracy and the changes, were developed. Three-dimensional imaging of the casts was unsuccessful, and thus the development of 3D evaluation system was left as a future research topic.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

Advances in Management of Voice and Swallowing Disorders

Special Issue “Advances in Management of Voice and Swallowing Disorders” is dedicated to innovations in screening and assessment and the effectiveness of interventions in both dysphonia and dysphagia. In contemporary practice, novel techniques have been introduced in diagnostics and rehabilitative interventions (e.g., machine learning, electrical stimulation). Similarly, advancements in methodological approaches to validate measures have been introduced (e.g., item response theory using Rasch analysis), prompting the need to develop new, robust measures for use in clinics and intervention studies. Against this backdrop, this Special Issue focuses on studies aiming to improve early diagnostics of laryngological disorders and its management. This issue also welcomes the submission of studies on diagnostic accuracy and psychometrics performance of existing and newly developed measures. This includes but is not limited to studies investigating screening tools with sound diagnostic accuracy and robust psychometric properties. Furthermore, interventions with high levels of evidence in relation to clinical outcome using robust methodology (e.g., sophisticated meta-analytic approaches) are of great interest. This issue provides an overview of the latest advances in voice and swallowing disorders

Optimization based on genetic algorithms for image registration

Diplomová práce se zabývá globálními optimalizačními metodami a jejich využitím při registraci medicínských obrazů. Hlavní cíl spočívá ve vytvoření genetického algoritmu a testování jeho funkčnosti na syntetických datech. Kromě testovacích funkcí a obrazců byl algoritmus podroben i skutečným medicínským snímkům. K tomuto účelu se vytvořilo grafické uživatelské prostředí s volbou parametrů podle aktuální potřeby. Přidáním iterační gradientní metody se algoritmus stal hybridním genetickým algoritmem.Diploma thesis is focused on global optimization methods and their utilization for medical image registration. The main aim is creation of the genetic algorithm and test its functionality on synthetic data. Besides test functions and test figures algorithm was subjected to real medical images. For this purpose was created graphical user interface with choise of parameters according to actual requirement. After adding an iterative gradient method it became of hybrid genetic algorithm.