Tesis sobre el tema "Intraoperative evaluation"

Restoring a correct implant kinematics and providing a good ligament balance and patellar tracking is mandatory to improve clinical and functional outcome after a Total Knee Replacement. Surgical navigation systems are a reliable and accurate tool to help the surgeon in achieving these goals. The aim of the present study was to use navigation system with an intra-operative surgical protocol to evaluate and determine an optimal implant kinematics during a Total Knee Replacement.

Restoring a correct implant kinematics and providing a good ligament balance and patellar tracking is mandatory to improve clinical and functional outcome after a Total Knee Replacement. Surgical navigation systems are a reliable and accurate tool to help the surgeon in achieving these goals. The aim of the present study was to use navigation system with an intra-operative surgical protocol to evaluate and determine an optimal implant kinematics during a Total Knee Replacement.

Zahlreiche chirurgische Assistenzsysteme sind in der klinischen Praxis im Einsatz, um die Genauigkeit und Sicherheit medizinischer Eingriffe zu erhöhen. Die Verwendung von Bildgebungsverfahren durch solche Systeme und die Teilautomatisierung von Prozessen kann einen weiteren Schritt in Richtung höherer Effizienz chirurgischer Interventionen und höherer Patientensicherheit darstellen. Dies stellt jedoch große Herausforderungen an die Systementwickler, welche zur Evaluation dieser Systeme während der Konstruktion geeignete Konzepte und Testmethoden benötigen. Diese Arbeit hat zwei wesentliche Zielsetzungen: Zum einen soll vorgestellt werden, wie zur zielführenden Entwicklung eines duplexsonographisch geführten, semiautomatisch arbeitenden Assistenzsystems zur Gefäßpräparation (ASTMA-System) ein anthropomorphes, physiologisches Phantom anhand zuvor definierter, für die Entwicklung relevanter, Anforderungen konstruiert wurde. Dieses ermöglichte es, die Arbeitsprozesse des Systems und deren Eignung bereits in vitro umfangreich zu testen. Zum andern soll dargestellt werden, wie das Phantom hinsichtlich dieser Anforderungen in einer Studie validiert wurde, um zu gewährleisten, dass dieses für die Systementwicklung erforderliche Eigenschaften aufwies. Dadurch konnten wichtige Informationen über Nutzen und Limitierung der Verwendung des Phantoms und mögliche Probleme des ASTMA-Systems gewonnen werden. Hiermit soll demonstriert werden, wie ein Entwicklungs- und Validierungsansatz für ein Phantom als Testsystem zur Entwicklung und Evaluation ähnlicher komplexer medizintechnischer Systeme mit intraoperativer Bildgebung gestaltet werden kann und welchen Anforderungen solche Phantome genügen sollten. Dies kann dabei helfen, die Systementwicklung zielführend und ressourceneffizient durchzuführen, Probleme bereits während früher Entwicklungsschritte aufzudecken und zu lösen und die Eignung des Verfahrens des entwickelten Systems zu beurteilen.

Les tumeurs solides relèvent pour un très grand nombre de cas d’un traitement chirurgical. La réussite thérapeutique dépend de la qualité, de la précision de l’exérèse et de la capacité à « visualiser » les résidus tumoraux. Pour ce faire, différents marqueurs sont disponibles sur le marché, notamment radioactifs. Depuis peu, des émetteurs de positrons spécifiques sont disponibles, relançant l’intérêt des techniques de chirurgies radioguidées. Les objectifs de ces travaux ont été la conception, le développement et l’optimisation d’un détecteur de positons pour la localisation de la tumeur avant exérèse et des amas tumoraux résiduels après exérèse. L’avantage de la détection des positons est leur parcours dans les tissus mous, de quelques millimètres. Leur détection est donc plus précise et de meilleure sensibilité (1 à 3 ordres de grandeurs) que la détection de rayonnements gamma. Elle consiste en une technique d’imagerie de contact sur une profondeur de quelques millimètres. Nous avons donc développé 2 prototypes d’imageurs beta+ composés de photomultiplicateurs en silicone (SiPM). Le SiPM sont des photomultiplicateurs présentant les mêmes caractéristiques que les tubes photomultiplicateurs (PMT), tout en étant sensibles à une faible luminosité et de très petite dimension, ce qui est parfaitement adapté à la problématique. La tête de détection du premier prototype est l’association d’un scintillateur organique sur une matrice de SiPM. Cette configuration permet de réduire le bruit dû à la contamination du signal par des rayonnements gamma. La seconde configuration inclus une méthode de soustraction permettant d’améliorer la discrimination du bruit Gamma, sans l’éliminer totalement. Pour ce faire, un assemblage de deux scintillateurs séparés par un guide de lumière est utilisé. Le signal issu des extrémités du scintillateur sont discriminés par l’analyse des différentes distributions de lumière sur la matrice SiPM. Dans les deux cas, le détecteur a été conceptualisé de façon à positionner la tête de détection dans un boitier mécanique comprenant une électronique de lecture miniaturisée. Différents designs de la sonde Beta+, prenant en compte le matériau et l’épaisseur du scintillateur, la fenêtre de propagation lumineuse et le réflecteur optique ont été simulés avec MonteCarlo et mesurés expérimentalement. Ces paramètres ont été optimisés de façon à ce que la sonde offre les meilleures performances en termes de sensibilité de détection des positons, discrimination du bruit Gamma, résolution et distorsion spatiale et uniformité de réponse. L’influence des différents algorithmes de reconstruction sur les performances spatiales ont été étudiées et une première étude préclinique du détecteur sur fantôme a pu être réalisée avec la première configuration de détecteur
Extent and accuracy of surgical resection is a crucial step in the therapy of operable solid tumors. The recent availability of specific tumor-seeking agents, positron labeled, renewed the interest for radioguided surgery. The detection of beta particles, due to their short range, allows a more sensitive and accurate tumor localization. Since no mechanical collimation is necessary, it is possible to design probes with a sensitivity increased by one to three orders of magnitude compared to gamma detectors. The beta particle short range also reduces the contamination from distal non-specific radiotracers uptake region, which results in a increased signal-to-noise-ratio. Conversely, beta detection requires sensors to be extremely compact in order to operate in contact with the surveyed tissues in narrow surgical cavities. This thesis takes place in that context. Its aim was to develop an intraoperative positron imaging probe based on the silicon photomultiplier technology (SiPM) and to evaluate its ability to perform in real time tumor localization and post-operative control of the surgical cavity. During this work, two prototypes of intraoperative positron imaging probe were developed. The first detector design is based on the use of a single organic scintillator coupled to an array of SiPMs. This configuration uses a small sensitive volume to reduce the contamination noise coming from the annihilation gamma rays. The second version of the probe implements a subtraction method allowing to improve gamma rejection efficiency. This configuration uses a stack of two scintillators separated by a light guide. The events interacting in the top and the bottom scintillator are discriminated by the analysis of the different light distributions on the SiPM array. Different designs of the positron imaging probes, including scintillator material and thickness, light spreading window and optical reflector, were investigated with Montecarlo simulations and measurements. Their impact on the probes performances were optimized in terms of positron sensitivity, gamma ray rejection efficiency, spatial resolution and bias and uniformity of response. The effect of different reconstruction algorithm on spatial performances was also studied. Finally, the objective of developing an intraoperative probe fully operational in the operating room has been achieved by the design of dedicated miniaturized electronic readouts and mechanical housing. In the last part of my thesis, the evaluation of the single scintillator configuration in a realistic clinical environment was performed with 18F-FDG phantoms. We showed that the low intrinsic sensitivity of this probe to gamma radiations allows to detect tumor volumes as small as 14 mg for uptake properties corresponding to currently available radiotracers and acquisition times compatible with the surgery duration

Probe-based confocal laser endomicroscopy (pCLE) is an emerging imaging tool that allows real-time in situ morphological imaging at cellular and subcellular resolution. Its ability to image morphological features of epithelial surfaces of the gastrointestinal tract, biliary tree and respiratory tree rendered differentiation of macroscopically inconspicuous neoplastic and non-neoplastic tissues possible in real-time. However, its role outwith the endoluminal environment for surgical applications has been comparatively sparsely investigated and little reported on its ability to characterise morphological features beyond endoluminal applications. This thesis aims to systematically evaluate the potential pCLE has in visualization of soft tissue morphology in applications pertaining to breast conserving surgery (BCS), parathyroid surgery and thyroid surgery; whereby morphological information regarding cavity wall margin status, tissue-specific entity and viability status of preserved parathyroid glands (PG), respectively, could potentially guide decision-making intraoperatively. The perceptions that pCLE imaging is confined to endoluminal mucosal surfaces, the inability of pCLE to perform image acquisition through sterile transparent sheaths and the inability of surgeons to interpret pCLE images were interrogated using three small feasibility studies. Firstly, in a study carried out on a live, anaesthetised, porcine model, pCLE image acquisition of morphological architecture of soft tissues of the neck e.g. thyroid, lymph nodes, adipose, skeletal and smooth muscles, were shown to be feasible in an intraoperative field and the presence dried blood on the tissue surface did not impede the consistency of morphological architecture visualization. Secondly, we demonstrated that utilization of a sterile transparent sheath did not impede pCLE image acquisition and that the quality of images obtained was comparable to that of without the sheath. Thirdly, we have shown that surgeons with little or no histopathology background were able to acquire the relevant pattern recognition skills to interpret pCLE images following a training session utilizing a validated pCLE morphological classification from colorectal lesions. Building upon these discoveries, we elucidated the potential of pCLE to image neoplastic and non-neoplastic breast morphology with the envisaged application of identifying residual cancerous foci intraoperatively, thereby guiding operative decision making based on real-time breast cavity scanning during BCS. Preliminary ex vivo analyses from 71 freshly excised, acriflavine-stained neoplastic and non-neoplastic tissues samples from 50 breast cancer patients show excellent correlation with histopathology findings. In particular, the glandular structures, adipocytes and collagen fibres of non-neoplastic breast tissues were readily visualised on pCLE images. These were distinguishable from the markedly haphazard and hypercellular architecture exhibited by invasive and non-invasive carcinoma. We developed a classification based on description of pCLE morphology unique to neoplastic and non-neoplastic breast morphology and validated this with 17 histopathologists and surgeons through a systematic pattern recognition training session based on this classification where they were subsequently subjected to objective assessment of 50 pCLE images while blinded to histopathology results. The overall mean accuracy of pCLE image interpretation for histopathologists and surgeons were 94% and 92%, respectively. The overall inter-observer agreement was ‘almost perfect’ (κ=0.81) for the former and ‘substantial’ (κ=0.77), for the latter. We explored the role of intravenous fluorescein sodium (FS) in a prospective, cross-sectional, observational study of 10 patients undergoing BCS where they received between 1.5ml to 3.5ml of intravenous bolus of 10% fluorescein sodium (FS) intraoperatively. Ex vivo analyses of FS-stained breast samples showed that dense fibrous tissue response evoked by infiltrating tumor cells were readily visualised as fluorescent regions with haphazardly arranged, amorphous-looking collagen fibres. However, the lack of nuclei visualization rendered differentiation of neoplastic from non-neoplastic tissues impossible. Nevertheless, the uniformity that FS staining imparts to all tissue layers facilitated creation of longer and meaningful pCLE mosaics. These findings could have important implications where tissue deformation could result in AH-stained layers intermittently fail to coincide with the optical slice imaged at the respective depth. The promising findings of AH-stained breast tissues were found to be potentially relevant in parathyroid surgery. Similar analyses on freshly excised AH-stained parathyroid specimens from 35 patients undergoing parathyroidectomy for primary and secondary hyperparathyroidism showed nest-like arrangements of parenchymal cells, fibrovascular septum and microfollicles of diseased PGs were readily identifiable on CE images and these were consistent with histopathological findings. Following pattern recognition training based on an in-house developed classification system, these were distinguishable from epithelial-lined thyroid follicles and polygonal-shaped adipocytes with mean accuracies of 94% and 93% for histopathologists and surgeons, respectively, and high overall inter-observer agreement, κ=0.82. Where intraoperative identification of diseased PGs presents a challenge especially in multi-glandular disease and re-operative surgery, pCLE could potentially facilitate its recognition. Finally, the role for pCLE imaging of PG vasculature was explored by means of an intraoperative clinical study utilising a sterile-transparent draped pCLE probe on 20 patients undergoing thyroid and parathyroid surgery. Utilising intravenous FS, branched-vessels including capillary networks were readily visualised. Vascular flow on viable glands was depicted by unidirectional, high velocity thrusts of dark-coloured erythrocytes within hyperfluorescent vessels or diffusely in the parenchyma whereas these were absent on non-viable (post-excision) glands. Further analysis on preserved PGs showed that absence of blood flow was found in patients who had sub-optimal post-operative parathyroid function. Given that visual assessment of tissue discolouration is not a reliable method of determining parathyroid gland viability during thyroidectomy, information regarding viability of preserved PGs decisions could potentially aid decisions pertinent to autotransplantation remains challenging. This thesis significantly expands upon the potential intraoperative applications of pCLE. Evidently, these findings are preliminary and warrant further evaluation in well-powered clinical trials. However a systematic approach to investigate the optimal trade-offs between the optical resolution requirements of tissue morphology visualization and deployability of pCLE probe holds the key to successful clinical translation. In particular, evaluation of a robust mechatronically enhanced platform equipped with the flexibility to cater for tissue surface deformation and precision mechanisms that generates accurate spatio-temporal localisation in real-time to aid intraoperative decision making constitutes the next stage of research priorities.

No Brasil a principal causa de hipertensão portal é a esquistossomose mansônica na sua forma hepato-esplênica, classificada como pré-sinusoidal. Esta doença adquire grande importância epidemiológica, por acometer indivíduos jovens, com função hepática preservada, e por atingir uma grande parcela da população (cerca de 1 milhão de indivíduos). Destes, cerca de 12 a 52% irão apresentar hemorragia digestiva por ruptura de varizes de esôfago. Não existe até o momento nenhum tratamento que se estabeleça como de consenso para esta enfermidade, porém há uma preferência dos autores para o tratamento cirúrgico e, no Brasil, esta recai sobre a desconexão ázigo-portal e esplenectomia geralmente associada a escleroterapia endoscópica das varizes no pós-operatório. Não estão bem estabelecidas as alterações hemodinâmicas portais decorrentes do tratamento cirúrgico da hipertensão portal e sua influência no resultado deste tratamento. Com o objetivo de avaliar o impacto imediato da desconexão ázigo-portal e esplenectomia (DAPE) na pressão portal e os resultados do tratamento cirúrgico da hipertensão portal no que se refere à recidiva hemorrágica e ao calibre das varizes de esôfago, foram estudados 19 pacientes portadores de esquistossomose hepato-esplênica e hipertensão portal com história de hemorragia digestiva alta por ruptura de varizes esofágicas, com idade média de 37,9 anos. Durante a cirurgia foi avaliada a pressão portal, no início e no final do procedimento através da cateterização da veia porta por cateter de polietileno introduzido por veia jejunal. Todos os pacientes foram submetidos à endoscopia no pré e pós-operatório para avaliar a variação do calibre das varizes esofágicas. Os pacientes foram acompanhados ambulatorialmente e o tempo médio de seguimento foi de 26 meses. Como resultado obteve-se uma queda na pressão portal média de 31,3% após a DAPE (p=0,0001). No acompanhamento pós-operatório houve redução significativa do calibre das varizes esofágicas quando comparadas com a avaliação pré-operatória (p < 0,05). Apenas um paciente (8,3%) apresentou, durante o acompanhamento, recidiva hemorrágica porém, esta foi decorrente de úlcera gástrica e não de varizes esofágicas. Por fim chegou-se à conclusão de que a desconexão ázigo-portal e esplenectomia promoveu queda imediata na pressão portal, com conseqüente diminuição do calibre das varizes esofágicas, tendo sido eficaz no tratamento da hipertensão portal destes pacientes
The main cause of portal hypertension in Brazil is the hepato-splenic form of mansonic schistosomiasis, which is classified as pre-sinusoidal. It acquires major epidemiological importance because it occurs in young individuals and affects a huge parcel of the population (around 1 million people), 12 to 52% of whom will present digestive hemorrhage due to rupture of esophageal varices. There is no consensus treatment for this disease up to the moment, but there is a predilection for the surgical approach. In Brazil, the most employed technique is the esophagogastric devascularization with splenectomy (EGDS), generally associated to late postoperative endoscopical sclerotherapy of the esophageal varices. The hemodynamic alterations in the portal flow resulting from the surgery and their possible influences on the outcome are not well established. With the aim of evaluating the immediate impact of the EGDS upon the portal pressure as well as the results of the surgical treatment on the digestive hemorrhage recurrence and the caliber of the esophageal varices, 19 patients (11males, aged between 18 and 61 years) with hepato-splenic schistosomiasis, presenting portal hypertension and previous episodes of digestive hemorrhage were studied. None of the patients had received any treatment prior to the surgery. The portal pressure was assessed at the beginning and the end of the EGDS through catheterization of the portal vein with a polyethylene catheter introduced through a branch of a jejunal vein. All the patients were submitted to digestive endoscopy before and after the surgery (2 months), in order to classify the caliber of the esophageal varices according to Palmer\'s classification. They also entered the continuous program of endoscopical evaluation and sclerotherapy. The mean clinical follow up period was 26 months. Our results showed that the portal pressure had diminished in all the patients, with a mean decrease of 31.3% after the EGDS. In the postoperative follow up (1 month), the esophageal varices showed a statistically significant reduction in their calibers, when compared to the pre-surgical measurements (p=0.004). Only one patient presented digestive hemorrhage during the follow up period, but it was due to gastric ulcer and not to rupture of esophageal varices. These results have demonstrated that the EGDS promotes an immediate decrease in the portal pressure and a reduction in the caliber of the esophageal varices, thus contributing to the good results of this technique. With the association of EGDS and sclerotherapy of the esophageal varices, no hemorrhagic episodes were observed in this series, during the study

碩士
高雄醫學大學
醫學影像暨放射科學系碩士在職專班
104
The application of flat-panel detector mobile C-arm machine in the vertebral pedicle screw insertion can reduce the risk of surgery and surgery time. This study is to evaluate the radiation dose in vertebral pedicle screw insertion using flat-panel C-arm machin radiation dose e and Random phantom. In this study, we selected prosthesis is a female Rando phantom, with a height of 155 cm and weight of 50 kg, respectively. The prosthesis prone X-ray beam anterior posterior and horizontal projection is simulated the real operation position. The radiation doses of lumbar (L1-S1) and lumbar thoracic (T9-L2) are measured. The comparison of different X-ray frame rate (30, 15, 7.5) and limit collimate range are also measured to evaluate the radiation dose. The experiment of Rando phantom with perspective for one minute. Anterioroposter projection with limit collimate range in the lumbar studies revealed of 21.5 mGy and 24.3 mGy. Horizontally projection with limit collimate range in the lumbar spine studies revealed of 25.9 mGy and 32 mGy. The anterioroposter projection with limit collimate range of thoracolumbar spine studies revealed of 24.5 mGy and 27.2 mGy. The Horizontally projection with limit collimate range of thoracolumbar spine studies revealed of 23.4 mGy, and 27.2 mGy . Lumbar horizontal projections with the rate 30, 15, 7.5 frame are measure, respectively. and revealed 24.3 mGy, 17.5 mGy and 7.8 mGy. The 15 frame rate can reduce the patient radiation dose in 18% and the 7.5 frame rate can reduce the patient radiation dose in 63%. The result of this study, we reduce the patients radiation dose by the decreasing of the X-ray frame rate and the limit collimate range can improve image contrast, but to improve patient the radiation dose of 20%. The lowest X-ray frame rate to carry on the localization was performed by Department of orthopedic surgery, and can reduced to 63% radiation doses original.

Zahlreiche chirurgische Assistenzsysteme sind in der klinischen Praxis im Einsatz, um die Genauigkeit und Sicherheit medizinischer Eingriffe zu erhöhen. Die Verwendung von Bildgebungsverfahren durch solche Systeme und die Teilautomatisierung von Prozessen kann einen weiteren Schritt in Richtung höherer Effizienz chirurgischer Interventionen und höherer Patientensicherheit darstellen. Dies stellt jedoch große Herausforderungen an die Systementwickler, welche zur Evaluation dieser Systeme während der Konstruktion geeignete Konzepte und Testmethoden benötigen. Diese Arbeit hat zwei wesentliche Zielsetzungen: Zum einen soll vorgestellt werden, wie zur zielführenden Entwicklung eines duplexsonographisch geführten, semiautomatisch arbeitenden Assistenzsystems zur Gefäßpräparation (ASTMA-System) ein anthropomorphes, physiologisches Phantom anhand zuvor definierter, für die Entwicklung relevanter, Anforderungen konstruiert wurde. Dieses ermöglichte es, die Arbeitsprozesse des Systems und deren Eignung bereits in vitro umfangreich zu testen. Zum andern soll dargestellt werden, wie das Phantom hinsichtlich dieser Anforderungen in einer Studie validiert wurde, um zu gewährleisten, dass dieses für die Systementwicklung erforderliche Eigenschaften aufwies. Dadurch konnten wichtige Informationen über Nutzen und Limitierung der Verwendung des Phantoms und mögliche Probleme des ASTMA-Systems gewonnen werden. Hiermit soll demonstriert werden, wie ein Entwicklungs- und Validierungsansatz für ein Phantom als Testsystem zur Entwicklung und Evaluation ähnlicher komplexer medizintechnischer Systeme mit intraoperativer Bildgebung gestaltet werden kann und welchen Anforderungen solche Phantome genügen sollten. Dies kann dabei helfen, die Systementwicklung zielführend und ressourceneffizient durchzuführen, Probleme bereits während früher Entwicklungsschritte aufzudecken und zu lösen und die Eignung des Verfahrens des entwickelten Systems zu beurteilen.

碩士
元培醫事科技大學
醫學影像暨放射技術系碩士在職專班
104
The purpose of this study is to verifythe quality assurance and dose evaluation for a intraoperative low-energy photon radiotherapeuic equipment with 50-kV miniature radiation source system. To provide the breast cancer patients have the same healing effect and reduce side effects and reduce the risk of contralateral breast cancer-bearing. In this experiment, we used radiation color film (GAFCHROMIC ® EBT3 Dosimetry Film) to perform the relevant measures. These data allows users to understand the benefits and limitations of the instrument use, on the other hand, to obtain the relevant data before the actual implementation of patient treatment. At first, our team performed radioactivity testing in three operating roomr with X-ray photography and basic radiation protection.The control zone (<10μSv / h) and outside control areas (<0.5μSv / h) are in compliance with the provisions of the Radiation Protection Safety. Next, the characteristics and the physical parameters were measured on the equipment: Radial Dose Function had 4% deviation, Anisotropy Function axis around 45 rooms had an deviation less than 5%, Gamma Index 4π direction is also more than 90%, benchmark with (2%, 2mm).BrachyVisionTM establish the first optimized treatment planning computer system for IORT in Taiwan. The of results of this study can help surgeons, radiation oncologists and medical teams.To realize this radiotherapy machine and to achieve accurate and personalized treatment in medical therapy.Finally,we hope the study can improve the medical level of domestic breast cancer patients.

Background and Objective In stereotactic brain tumor biopsies, the combination of real-time fluorescence spectroscopy with the detection of microvascular perfusion using laser Doppler flowmetry provides an improved localization of the brain tumor while decreasing the risk of intra-cranial hemorrhage. The surgeon using the measurement probe is required to view signal values on a screen or usually, when her or his visual focus is directed at the patient, the verbal feedback of a biomedical engineer who is monitoring the measurement signals is needed. In this process possible important information can be overlooked and time is lost. The aim of the thesis was the development a visual and auditory user interface (UI) for use in stereotactic brain tumor biopsies. Materials and Methods The system translates the fluorescence intensity of protoporphyrin IX (PpIX) into sound and visual indicators that are easy and fast to recognize and transmits warning signals in case of signal error or the detection of microvascular perfusion. The increasing and de-creasing fluorescence values at tumor margins were reproduced to improve the precision of de-tecting varying fluorescence intensities when entering tumor tissue with color gradient models. The algorithm produced five signal values when specific fluorescence intensities were measured and compared at different wavelengths.For the development of the UI, a user-centered design was implemented. The user-, operating room- and safety requirements were gathered by communicating with the biomedical engineers and neurosurgeons who had experience in working with fluorescence guided brain tumor biop-sies. The requirements were considered when designing the UI’s features in LabVIEW and the auditory feedback was generated using OSC (Open Sound Control). The user interface intended to deliver measurement data to the user that triggered a high response accuracy by being easy to understand while inducing high user acceptance. The user interaction and function response accuracy of the visual and auditory interface were evaluated in statistical tests where operating room situations were mimicked. The user acceptance of the UI was evaluated. Results Signals for no, low (increasing and decreasing) and high fluorescence indicators, as well as two warning indicators for a blocked signal and vessel occurrence were represented visually and auditorially by the user interface. An intensity/time graph and intensity/wavelength graph, along with the option of recording measurement files and opening saved files allowed the inspec-tion of detailed measurement values. The user study exhibited auditory response accuracy of 95 ± 3% in the intuition test and 91±16% in a memory test. The testing of the response accuracy of the individual signal values displayed accurate responses in 84% to 100% of times a signal was played back. The user acceptance rating of the auditory and visual interface showed no negative results. Conclusion A UI was developed to visually and auditorially represent measurement values to a neurosurgeon performing a stereotactic brain tumor biopsy procedure and biomedical engineers monitoring the measurement signals. The visual display was successful in representing data in a way that was easy to understand. The auditory interface showed high response accuracies for the individual tones representing measurement values. The majority of the test subjects per-ceived the signals to be intuitive, easy to understand and easy to remember. The auditory and visual UI showed high user acceptance ratings, indicating that the user interface was useful and satisfactory in its application.

碩士
中山醫學大學
醫學影像暨放射科學系碩士班
106
In recent years, the newly developed intraoperative radiotherapy (IORT) is the first choice for early breast cancer patients. Radiation homogeneity of this technique have been questioned to the patients and physicians. A left breast with a 30 cm3 cavity of Rando phantom had been developed and made of polymethylmethacrylate (PMMA). Thermoluminescent dosimetry (TLD) approach was used to evaluate radiation doses under 20 Gy, 50 kV of Xoft Axxent exposure of extra radiations undergoing IORT. Doses was 20 Gy at the surface of balloon applicator, 17.04 Gy was found at the 0.7 cm away from surface, and dropped apparently. More clearly dropped, 6.88 Gy was indicated at the 1.2 cm away from surface. This study will be useful and recommended to the relatives, physicians and radiologists and authorit.