The aim of this research is to analyse how adaptation / standardisation, trust and network development counter the challenges created by intangibility and heterogeneity of service in the case of Philippine Gamma Knife Incorporated. This research used qualitative data that were gathered through unstructured interviews, direct observation and documents. The adaptation / standardisation, trust and network facilitate service visibility and decrease heterogeneity of a health care service. Among the variables adaptation / standardisation signifies an important role; however, trust manifestation was concluded more significant compared to network in a cultural environment such as that found in the Philippines. Moreover, culture was found to be an important role in the development of adaptation / standardisation, trust and network processes.

ABSTRACT Title: Services Marketing in a Cross-Cultural Environment – The Case of Elekta in Russia Level: Final assignment for Master Degree in Business Administration Authors: Alena Bazyleva and Maria Zaytseva Supervisor: Dr. Maria Fregidou-Malama Aim: The aim of this research is to investigate how the products and services of the Swedish company Elekta are marketed in Russia, a country with cultural environment different from Sweden. For this purpose such aspects of marketing strategy as adaptation/standardization, trust and network development, which help to decrease the influence of intangibility and heterogeneity of services, are examined. Method: In present research explanatory applied type of study was used to describe services marketing process. Combination of induction and deduction methods, and qualitative methods of research were used. Case study of Swedish company Elekta was chosen as the research area. Primary data was collected through survey by means of semi-structured interviews and open questionnaires. Secondary data was collected from sources such as relevant books, scientific articles, company brochure, and websites of company and its clients. Results and conclusion: The research reveals that trust, network building, balance of adaptation and standardization strategies, employed by Elekta company, help to overcome heterogeneity and intangibility of its services in Russian market. It has also been found that the image of Sweden as a country of origin plays an important role in trust establishment in Russia, but in a sense that it is a foreign country, not Sweden in particular. Moreover, it is suggested, that organizational structure of international company, matrix structure in this particular case study, favours the development and effectiveness of the discussed variables. In spite of such characteristics of Russian market as high bureaucracy, corruption, “blat” network, unstable laws, etc., this market is considered to be a promising emerging market for international business. Russian national culture displays large power distance, high uncertainty avoidance, collectivist and feminine values, which influence the whole society and the business sphere as well. Suggestions for future research: It would be beneficial for future research to expand the range of complementing studies, examining the cases of Elekta in different countries and emerging markets in particular. In addition, in order to develop international services marketing theory, it is necessary to include other services industries in the scope of research. Furthermore, getting feedback from the patients, who experienced treatment on Elekta equipment, can contribute to the future research. Contribution of the thesis: The modification and adaptation of the theoretical framework of Fregidou-Malama and Hyder (2011) made by authors of this study contributes to the theory of international services marketing process. In addition, as there is lack of research in this area for health care sector, this study can be valuable addition to this research area. Research of the case of Elekta in Russia complements the range of studies on international services marketing process in health care sector with the cases of Elekta company in different countries: Egypt, China, the Philippines, Brazil, Hong Kong. Besides, current research has certain practical value: it is beneficial for international companies expanding into emerging markets in general and in Russian market in particular. This research may help to increase awareness about Elekta treatment solutions. Key words: Elekta, Gamma Knife, Russia, Services Marketing, Services characteristics, Network, Trust, Adaptation, Standardization, Culture, Organizational structure.

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Any center planning to install a Gamma Knife radiosurgery unit has to provide for an efficient shielding of the treatment room, to protect the patient, the staff and the public, against undesired radiation. The shielding barrier design is controlled by national and international recommendations; the reference documents for gamma ray radiotherapy facilities are the National Council on Radiation Protection and Measurements (NCRP) reports 49 and 151. However, some facts highlighted in this thesis point out that NCRP methods are ill-adapted to the Gamma Knife. Spectroscopic measurements were performed around the Gamma Knife with a Germanium detector. They revealed that the radiation field contains few high energy photons, is highly anisotropic, and that the leakage level is much lower than the NCRP estimation. These observations led to the development of a new approach to determine the necessary shielding, based on the actual and directly measurable radiation field around the unit. This method would reduce the shielding oversizing induced by the unsuitability of the NCRP recommendations for the Gamma Knife.

C-arm Cone Beam CT (CBCT) systems – due to compact size, flexible geometry and low radiation exposure – inaugurated the era of on-board 3D image guidance in therapeutic and surgical procedures. Leksell Gamma Knife Icon by Elekta introduced an integrated CBCT system to determine patient position prior to surgical session, thus advancing to a paradigm shift in facilitating frameless stereotactic radiosurgeries. While CBCT offers a quick imaging facility with high spatial accuracy, the quantitative values tend to be distorted due to various physics based artifacts such as scatter, beam hardening and cone beam effect. Several 3D reconstruction algorithms targeting these artifacts involve an accurate and fast segmentation of craniofacial CBCT images into air, tissue and bone. The objective of the thesis is to investigate the performance of deep learning based convolutional neural networks (CNN) in relation to conventional image processing and machine learning algorithms in segmenting CBCT images. CBCT data for training and testing procedures was provided by Elekta. A framework of segmentation algorithms including multilevel automatic thresholding, fuzzy clustering, multilayer perceptron and CNN is developed and tested against pre-defined evaluation metrics carrying pixel-wise prediction accuracy, statistical tests and execution times among others. CNN has proven its ability to outperform other segmentation algorithms throughout the evaluation metrics except for execution times. Mean segmentation error for CNN is found to be 0.4% with a standard deviation of 0.07%, followed by fuzzy clustering with mean segmentation error of 0.8% and a standard deviation of 0.12%. CNN based segmentation takes 500s compared to multilevel thresholding which requires ~1s on similar sized CBCT image. The present work demonstrates the ability of CNN in handling artifacts and noise in CBCT images and maintaining a high semantic segmentation performance. However, further efforts targeting CNN execution speed are required to utilize the segmentation framework within real-time 3D reconstruction algorithms. / C-arm Cone Beam CT (CBCT) system har tack vare sitt kompakta format, flexibla geometri och låga strålningsdos startat en era av inbyggda 3D bildtagningssystem för styrning av terapeutiska och kirurgiska ingripanden. Elektas Leksell Gamma Knife Icon introducerade ett integrerat CBCT-system för att bestämma patientens position för operationer och på så sätt gå in i en paradigm av ramlös stereotaktisk strålkirurgi. Även om CBCT erbjuder snabb bildtagning med hög spatiel noggrannhet så tenderar de kvantitativa värdena att störas av olika artefakter som spridning, beam hardening och cone beam effekten. Ett flertal 3D rekonstruktionsalgorithmer som försöker reducera dessa artefakter kräver en noggrann och snabb segmentering av kraniofaciala CBCT-bilder i luft, mjukvävnad och ben. Målet med den här avhandlingen är att undersöka hur djupa neurala nätverk baserade på faltning (convolutional neural networks, CNN) presterar i jämförelse med konventionella bildbehandlings- och maskininlärningalgorithmer för segmentering av CBCT-bilder. CBCT-data för träning och testning tillhandahölls av Elekta. Ett ramverk för segmenteringsalgorithmer inklusive flernivåströskling (multilevel automatic thresholding), suddig klustring (fuzzy clustering), flerlagersperceptroner (multilayer perceptron) och CNN utvecklas och testas mot fördefinerade utvärderingskriterier som pixelvis noggrannhet, statistiska tester och körtid. CNN presterade bäst i alla metriker förutom körtid. Det genomsnittliga segmenteringsfelet för CNN var 0.4% med en standardavvikelse på 0.07%, följt av suddig klustring med ett medelfel på 0.8% och en standardavvikelse på 0.12%. CNN kräver 500 sekunder jämfört med ungefär 1 sekund för den snabbaste algorithmen, flernivåströskling på lika stora CBCT-volymer. Arbetet visar CNNs förmåga att handera artefakter och brus i CBCT-bilder och bibehålla en högkvalitativ semantisk segmentering. Vidare arbete behövs dock för att förbättra presetandan hos algorithmen för att metoden ska vara applicerbar i realtidsrekonstruktionsalgorithmer.

Radiation shielding is a central part of the design of treatment rooms for radiation therapy systems. The dose levels that medical staff and members of the public can be exposed to outside the treatment rooms are regulated by authorities and influence the required wall thicknesses and possible locations for the systems. Several standard methods exist for performing shielding calculations, but they are not well adapted to the stereotactic radiosurgery system Leksell Gamma Knife because of its self-shielding properties. The built-in shielding makes the leakage radiation anisotropic and generally have lower energy than the primary radiation from the Gamma Knife's cobalt sources. Oversimplifications made in the standard shielding calculation methods regarding the field can lead to excessively thick shielding and limit the number of suitable locations for the system.  In this thesis project, a simulation-based dose calculation algorithm was developed, that uses Monte Carlo-generated data in two steps. The algorithm uses a phase space to accurately describe the radiation field around the Gamma Knife. Information about individual photons in the field is then combined with a generated library of data describing the resulting dose outside a wall depending on the wall thickness and the photon energy. The dose calculation algorithm is fast enough to be integrated into optimization processes, in which the algorithm is used iteratively while varying room design parameters. Demonstrated in this report is a case with a room of fixed size, in which the Gamma Knife's position and the walls' thicknesses are varied, with the aim to find the room design resulting in the minimum wall thicknesses needed to achieve acceptable dose levels outside. The results in this thesis indicate that the dose calculation algorithm performs well and could likely be used in more complex optimizations with more design variables and more advanced design goals. / Strålsäkerhet är en viktig aspekt vid uppförandet av behandlingsrum för strål-terapisystem. Strålningsnivåerna som sjukvårdspersonal och allmänheten kan exponeras för utanför behandlingsrummet regleras av myndigheter och påverkar vilken väggtjocklek som behövs och vilka platser som är lämpliga att placera systemen på. Flertalet metoder för strålskyddsberäkning existerar, men de är inte väl anpassade till det stereotaktiska radiokirurgiska systemet Leksell Gamma Knife, eftersom det har ett inbyggt strålskydd. Det inbyggda strålskyddet gör att strålfältet runt Gamma Knife är anisotropt och generellt har lägre energi än primärstrålningen från systemets koboltkällor. Förenklingar som görs rörande strålfältet i flera existerande metoder för strålskyddsberäkning kan leda till att överdrivet tjocka strålskydd används eller begränsa antalet lämpliga platser att placera systemet på. I detta projekt utvecklades en dosberäkningsalgoritm, som i två steg använder data genererad genom Monte Carlo-simuleringar. Algoritmen använder ett fasrum för att detaljerat beskriva strålfältet runt Gamma Knife. Information om enskilda fotoner i fältet används sen i kombination med ett genererat bibliotek av data som beskriver det dosbidrag som en foton bidrar med utanför behandlingsrummet, baserat på fotonens energi och väggarnas tjocklek. Dosberäkningsalgoritmen är snabb nog att integreras i optimeringsprocesser där den används iterativt samtidigt som rumsdesignparametrar varieras. I denna rapport demonstreras ett fall med ett rum av bestämd storlek, där positionen av Gamma Knife i rummet och väggarnas tjocklekar varieras. Optimeringens syfte i exemplet är att hitta den rumsdesign som med de minsta väggtjocklekarna resulterar i acceptabla strålningsnivåer utanför rummet. Resultaten tyder på att dosberäkningsalgoritmen sannolikt kan användas i mer komplexa optimeringar med fler designvariabler och mer avancerade designmål.

La radiochirurgie par Gamma Knife constitue une modalité thérapeutique reconnue de certaines affections cérébrales. Le traitement se base sur l’administration d’un rayonnement focalisé au niveau d’une cible intracrânienne. L’efficacité de ce traitement repose sur la délivrance d’une dose d’irradiation efficace au sein d’un volume-cible associé à la délivrance d’une dose d’irradiation négligeable à l’extérieur de ce même volume-cible. En pratique, la dose d’irradiation administrée à l’intérieur du volume-cible n’est pas distribuée de manière homogène, et la dose d’irradiation reçue par les tissus situés en-dehors du volume-cible n’est pas nécessairement faible. Notre travail est basé sur l’hypothèse que l’imperfection de la distribution de la dose d’irradiation au sein du volume-cible et en-dehors de celui-ci peut être responsable des échecs et des complications rencontrées en radiochirurgie. Dans deux modèles cliniques de traitement radiochirurgical, le schwannome vestibulaire et la névralgie du trijumeau, nous avons montré qu’il existait une relation entre les paramètres de distribution de dose d’irradiation et certains résultats du traitement radiochirurgical par Gamma Knife de ces pathologies. Nous avons développé deux modèles expérimentaux d’irradiation radiochirurgicale de rats, l’un ciblé sur le striatum et l’autre sur le nerf trijumeau, permettant d’analyser les conséquences histologiques des variations de la distribution de dose à l’intérieur du volume-cible ainsi qu’à distance de celui-ci. Nous avons démontré que la réponse radiobiologique des tissus irradiés était fortement dépendante de ce paramètre dosimétrique, et que ce dernier constituait une donnée de la planification chirurgicale aussi importante que la dose de prescription. Nous avons corrélé ces résultats avec certaines observations réalisées dans d’autres indications de traitement radiochirurgical ainsi que dans l’analyse histologique de tumeurs traitées par Gamma Knife. Ces études mettent en évidence le rôle important joué par l’optimalisation de la distribution de la dose d’irradiation dans l’amélioration des résultats cliniques du traitement radiochirurgical. Les valeurs optimales de la distribution de dose dans les différentes indications de traitement radiochirurgical doivent être recherchées, et les différentes méthodes mises à notre disposition lors de la planification dosimétrique pour améliorer la distribution de dose doivent être utilisées avec discernement pour obtenir la dosimétrie radiochirurgicale la plus parfaite possible. / Doctorat en sciences médicales / info:eu-repo/semantics/nonPublished

The Leksell Gamma Knife® (LGK) is a device for performing radiosurgery. The LGK contains approximately 200 radioactive sources whose beams intersect in a focal point in order to treat brain tumours. Quality assurance tools are used at Elekta to indirectly assess the number of sources in an LGK from the total amount of radiation. In order to increase patient safety, regulatory agencies have been asking for evidential proof of the number of sources in the LGK. This thesis' goal is to directly measure each source in the LGK and optimize the total detection time. To do this, a source detection system was developed with two parts, a radiation detection system and a moving gantry. Initial tests of the design were performed at Elekta and a final test was performed on an LGK at Karolinska Universitetssjukhuset. The results show that the proposed design has the possibility of detecting all sources in an LGK.

The Leksell Gamma Knife® is an instrument designed for high precision treatment of tumours and lesions located in the brain and upper spine. Today, the radioactive cobalt-60 sources can only move linearly along the radiation unit, but the machine could be modified to include rotational motion as well. We extend an existing linear programming approach to inverse planning for the Gamma Knife by examining the benefits from rotational degrees of freedom. The improvements offered from rotations are limited, but easy to make use of. We investigate the model in four patient cases, and find that an upper bound on the improvement of the optimization cost function is between 4.5% and 7.0% depending on case. With a total of four angles distributed uniformly over a 45 degree interval, one can in each case achieve a solution that performs up to within 1% of this bound. The average maximal improvements in terms of clinical metrics are 0.5% selectivity and 1.9% gradient index, at the cost of 5.9% worse beam-on time. No statistically significant change in coverage is found. A dynamic model based on column generation is proposed, which allows treatment during constant velocity angular motion and can achieve practically the same plan quality as the model with uniformly distributed angles at a significantly lower problem size. A similar algorithm can be designed to locate the most effective angles in a non-uniform manner that achieves better plans with fewer added rotational degrees of freedom. Trade-offs between memory and solution times are used to successively reduce the RAM occupation by around 90% and make significantly larger models computationally feasible to solve. A voxel clustering approach with emphasis on surface voxels, adapted to the radiosurgical framework, can significantly reduce the problem size while still producing competitive plans. / Strålkniven Leksell Gamma Knife® är ett instrument designat för högprecisionsbestrålning av tumörer och lesioner i hjärnan och övre delen av ryggraden. Idag kan de radioaktiva källorna endast förflyttas linjärt under behandlingen, men maskinen skulle kunna modifieras för att även tillåta rotationsrörelser. Vi utvidgar ett ramverk för inversplanering, formulerat som ett linjär-programmeringsproblem, genom att undersöka fördelarna med nya rotationsfrihetsgrader. Förbättringarna som rotationer möjliggör är begränsade, men kan relativt enkelt tas till vara. Vi undersöker de potentiella förändringarna i fyra patientfall och finner att den övre gränsen av förbättringarna för målfunktionsvärdet i optimeringsproblemet är mellan 4.5% och 7.0% beroende på fall. Genom att tillåta rotation av källorna till fyra jämnt fördelade vinklar över 45 grader kan man i samtliga fall hitta en lösning som är inom 1% från det bästa målfunktionsvärdet. De genomsnittliga förbättringarna i form av kliniska metriker är 0.5% selektivitet och 1.9% gradient-index, dock på bekostnad av en försämring av bestrålningstiden med 5.9%. Ingen tydlig förändring av täckningen kunde påvisas. En modell baserad på kolumngenerering, som tillåter behandling under rotation av kollimator-kroppen med konstant hastighet, föreslås. I denna modell kan praktiskt taget lika bra lösningar uppnås som för likformigt fördelade vinklar, men med betydligt mindre problemstorlek. En liknande algoritm kan lokalisera de mest effektiva vinklarna och åstadkomma samma plankvalitet med färre, men olikformt fördelade, rotationsfrihetsgrader. RAM-användningen kan reduceras med cirka 90% genom avvägningar mellan minne och beräknings-tider, vilket möjliggör lösning av probleminstanser som tidigare var beräkningsmässigt omöjliga. Klustringsmetoder av voxlar anpassade till strålkniven kan minska problemstorleken betydelsefullt medan de resulterande behandlingsplanerna är fortsatt konkurrenskraftiga.

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