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Breast cancer is the most frequent cancer worldwide. The x-ray mammography an important imaging technique for detection can succeed balance between low breast dose and high image quality with the achievement of high sensitivity and specificity. Special requirements lead to the continuing effort to optimize the mammographic technique. Different studies target in improvement of quality image and as a consequence increase the diagnostic accuracy of pathological findings. In this study Monte Carlo methods play a key role as it offers a safe, reliable, inexpensive and flexible tool for complicated studies in medical radiation physics. It gives the solution to a major limitation, the lack of quantitative objective measures of the characteristics of pathological findings inside the environment of a real mammographic image. Different pathological findings are simulated in this study with the help of Monte Carlo techniques having the same density with the area of a clinical mammogram where they are superimposed, creating the synthetic images. The whole followed procedure is presented. Finally a number of result images is created containing different types and sizes of pathological findings reaching the conclusion that calcifications can be very well simulated up to 200μm ,lesions as masses can be realistic up to 0.5cm and especially when the appropriate size is embedded in the suitable heterogeneous area. Finally, masses of air was a difficult task since turned to be difficult to simulate a realistic cyst. The simulation procedure and created synthetic images can be evaluated by experts and gives the opportunity as a future work for a large database to be created. Untrained scientists can take advantage of this procedure or evaluating the detactibility of CAD systems. / Ο καρκίνος του μαστού είναι ο πιο συχνός καρκίνος παγκοσμίως. Η μαστογραφία με ακτίνες Χ, μια σημαντική απεικονιστική τεχνική για ανίχνευση παθολογικών ευρημάτων μπορεί να επιτύχει ισορροπία μεταξύ χαμηλής δόσης μαστού και υψηλή ποιότητα εικόνας με την επίτευξη υψηλής ευαισθησίας και ειδικότητας. Ειδικές απαιτήσεις οδηγούν στη συνεχόμενη προσπάθεια για βελτιστοποίηση της μαστογραφίας.Διαφορετικές μελέτες στοχεύουν στη βελτίωση της ποιότητας της εικόνας και σαν συνέπεια αυξάνουν τη διαγνωστική ακρίβεια. Σε αυτή τη μελέτη οι μέθοδοι Monte Carlo παίζουν ένα σημαντικό ρόλο,καθώς προσφέρει ένα ασφαλές, αξιόπιστο, οικονομικό και εύχρηστο εργαλείο για πολύπλοκες μελέτες στην ιατρική ακτινοφυσική.Δίνει τη λύση σε ένα μεγάλο περιορισμό, την έλλειψη ποσοτικοποιημένων, αντικειμενικών μετρήσεων των χαρακτηριστικών των παθολογικών ευρημάτων μέσα στο περιβάλλον μιας πραγματικής μαστογραφικής εικόνας.Διαφορετικά παθολογικά ευρήματα προσομοιώνονται σε αυτή τη μελέτη με τη βοήθεια μεθόδων Monte Carlo διατηρώντας τη ίδια πυκνότητα με την περιοχή της κλινικής μαστογραφίας όπου θα τοποθετηθούν, δημιουργώντας συνθετικές εικόνες. Όλη η διαδικασία που ακολουθήθηκε παρουσιάζεται. Τελικά, μια ποσότητα από εικόνες αποτελέσματα δημιουργείται περιέχοντας διαφορετικούς τύπους και μεγέθη παθολογικών ευρημάτων, φτάνουμε στο συμπέρασμα οτι οι αποτιτανώσεις μπορούν να προσομοιωθούν μέχρι τα 200 μm, αλλοιώσεις σαν μάζες μπορούν να είναι ρεαλιστικές μέχρι 0.5cm και ειδικά όταν το κατάλληλο μέγεθος τοποθετείται στην κατάλληλη ετερογενή περιοχή. Τέλος, οι μάζες αέρα ήταν δύσκολο θέμα καθώς αποδείκτηκε δύσκολο να προσομοιωθεί μία ρεαλιστική κύστη. Η διαδικασία προσομοίωσης και οι συνθετικές εικόνες που δημιουργήθηκαν μπορούν να αξιολογηθούν από έμπειρους και να δώσει την ευκαιρία σαν μελλοντική δουλειά να δημιουργηθεί μια μεγάλη βάση δεδομένων. Μη εκπαιδευμένοι επιστήμονες μπορούν εκπαιδευτούν ή να αξιολογηθεί η ικανότητα ανίχνευσης των υπολογιστικών συστημάτων.

Mammography, either for screening or for the examination of a woman who displays symptoms of breast cancer, must be capable of revealing subtle differences in density and composition of breast parenchymal tissue, as well as the presence of any abnormalities. This is a challenging imaging task since connective tissue, glandular tissue, skin and fat must be simultaneously visualized and differentiated, while having very similar attenuation coefficients and thus low subject contrast. The detection of small low-contrast lesions is essential for screening mammography. Because the mammogram is a projected image of superimposed breast structures, it is generally more difficult to detect cancer in a dense breast pattern. This is attributed to minor differences in x-ray attenuation between lesions and the surrounding parenchymal. The visibility of small structures on a mammogram is restricted by the compromise between the image quality and the absorbed dose. This leads to a continuous drive for improved techniques, mainly with respect to improving the low contrast character of the technique. In the framework of this master thesis, the imaging performance of a wide range of mammographic spectra has been evaluated and their influence on imaging of inhomogeneities was studied. These spectra correspond to several combinations of anode (Mo, Rh, W) and filter (Mo, Rh, Nb, Zr Al, and Pd) materials and diameters (90–250 μm), and tube voltages (26-30 kVp), with 1 mm Be-window inherent filtration. A properly designed mathematical breast phantom was utilized, simulating water, containing two identical spherical inhomogeneities of air of various diameters. An earlier developed and validated Monte Carlo model (MASTOS), was utilized for the simulation studies. Utilizing the developed model, the influence of the factors affecting the x-ray spectrum (tube voltage, anode material, filter material) on the detectability of small low contrast lesions was investigated in terms of Contrast to Noise Ratio (CNR) and Contrast-Detail (CD) analysis. Results demonstrate that spectra mainly produced from W anodes and filtered with k-edge filters (Mo, Rh, Nb, Pd and Zr) provide improved imaging characteristics that is similar and in some cases better compared to commonly used Mo and Rh anodes filtered with k-edge filters, especially for inhomogeneities of larger diameters. However, in the case of inhomogeneities of smaller diameter softer spectra mainly produced from Mo anodes and spectra filtered with k-edge filters of low energy k-absorption edge provide better CNR. As far as the filter material is concerned, k-edge filters demonstrate improved imaging performance compared to Al filter. This is the reason that justifies the use of these filters in clinical mammographic procedure. Tube voltage has a limited effect on CNR for all inhomogeneity sizes. As a conclusion, the discriminability of low contrast details, in terms of CNR, depends on all the parameters affecting the x-ray spectrum, but especially on the combination of the anode material and filter. / Η μαστογραφία, είτε για απεικόνιση είτε για εξέταση γυναικών που παρουσιάζουν συμπτώματα καρκίνου του μαστού, πρέπει να είναι ικανή να αποκαλύπτει τόσο πολύ μικρές διαφορές στην πυκνότητα και σύσταση του μαστογραφικού παρεγχύματος, όσο και την παρουσία ανωμαλιών. Αυτή είναι μια αντικρουόμενη διαδικασία καθώς ο συνδετικός ιστός, ο αδενικός ιστός, το δέρμα και το λίπος πρέπει ταυτοχρόνως να απεικονιστούν και να διαφοροποιηθούν ενώ έχουν πολύ μικρές διαφορές στους συντελεστές εξασθένισης και γι’αυτό το λόγο χαμηλή αντίθεση θέματος. Η ανίχνευση μικρών χαμηλής αντίθεσης αλλοιώσεων είναι απαραίτητη για την απεικονιστική μαστογραφία. Επειδή το μαστογράφημα είναι μια προβολική εικόνα των δομών του μαστού, είναι γενικά πολύ δύσκολο να ανιχνευθεί ο καρκίνος σε ένα πυκνό μαστογραφικό παρέγχυμα. Αυτό αποδίδεται στις ασήμαντες διαφορές στην εξασθένιση των ακτινών χ μεταξύ των αλλοιώσεων και του περιβάλλοντος παρεγχύματος του μαστού. Η ανιχνευσιμότητα των μικρών δομών σε μια μαστογραφία περιορίζεται από τον συμβιβασμό ανάμεσα στην ποιότητας εικόνας και την απορροφούμενη δόση. Αυτό οδηγεί σε μια συνεχή προσπάθεια για βελτιωμένες τεχνικές, λαμβάνοντας υπόψη τα χαμηλής αντίθεσης χαρακτηριστικά της μαστογραφικής διαδικασίας. Στο πλαίσιο της παρούσας μεταπτυχιακής εργασίας αποτιμήθηκε η απεικονιστική ικανότητα ενός μεγάλου εύρους μαστογραφικών φασμάτων και μελετήθηκε η επίδρασή τους στην ανιχνευσιμότητα ανομοιογενειών. Τα φάσματα αυτά αντιστοιχούν σε διάφορους συνδυασμούς υλικών ανόδων (Mo, Rh, W), φίλτρων (Mo, Rh, Nb, Zr Al, and Pd) και υψηλών τάσεων με έμφυτο φιλτράρισμα 1mm παράθυρο Βe. Χρησιμοποιήθηκε ένα κατάλληλα σχεδιασμένο μαθηματικό ομοίωμα μαστού από νερό που περιέχει δύο πανομοιότυπες ανομοιογένειες αέρα διαφόρων διαμέτρων. Για τις μελέτες προσομοίωσης χρησιμοποιήθηκε ένα νωρίτερα ανεπτυγμένο και επικυρωμένο μοντέλο Monte Carlo, το MASTOS. Χρησιμοποιώντας το μοντέλο, διερευνήθηκε η επίδραση των παραγόντων που επηρεάζουν το μαστογραφικό φάσμα (υλικό ανόδου, υλικό φίλτρου, υψηλή τάση), στην ανιχνευσιμότητα μικρών χαμηλής αντίθεσης λεπτομερειών σε όρους αντίθεσης προς θόρυβο (CNR). Τα αποτελέσματα αποδεικνύουν ότι τα φάσματα που παράγονται από ανόδους W και φιλτράρονται με φίλτρα κ-αιχμής (Mo, Rh, Nb, Pd, Zr) δίνουν βελτιωμένα απεικονιστικά χαρακτηριστικά τα οποία είναι παρόμοια και σε μερικές περιπτώσεις καλύτερα συγκρινόμενα με φάσματα από ανόδους Mo και Rh φιλτραρισμένα με φίλτρα κ-αιχμής, ειδικά για τις μεγαλύτερες ανομοιογένειες. Παρολ’αυτά, στην περίπτωση των μικρότερων ανομοιογενειών τα μαλακά φάσματα που παράγονται από ανόδους Mo και φιλτράρονται με φίλτρα κ-αιχμής, με αιχμή απορρόφησης χαμηλής ενέργειας παρέχουν καλύτερο λόγο αντίθεσης προς θόρυβο (CNR). Λαμβάνοντας υπόψη το υλικό του φίλτρου, τα φίλτρα κ-αιχμής προσφέρουν καλύτερη απεικόνιση συγκρινόμενα με τα φίλτρα αλουμινίου (Al). Αυτός είναι ο λόγος που δικαιολογεί τη χρήση αυτών των φίλτρων στην κλινική μαστογραφική διαδικασία. Η υψηλή τάση έχει περιορισμένη επίδραση στον λόγο αντίθεσης προς θόρυβο για όλα τα μεγέθη ανομοιογενειών. Γενικά ως συμπέρασμα, η ανιχνευσιμότητα των χαμηλής αντίθεσης λεπτομερειών σε όρους αντίθεσης προς θόρυβο, εξαρτάται από όλους τους παράγοντες που επηρεάζουν το μαστογραφικό φάσμα, αλλά κυρίως από το υλικό της ανόδου και το υλικό του φίλτρου.

Η διπλωματική αυτή εργασία σχετίζεται με την ανίχνευση νεοπλασιών σε μαστογραφίες. Στις μέρες μας, έχουμε μία καλή εικόνα για τον τρόπο που δημιουργείται ο καρκίνος. Αυτό βοηθά στην βελτίωση της θεραπείας αλλά και στην μείωση εμφάνισης της πάθησης. Το κλειδί για την επιτυχή καταπολέμηση της νόσου είναι η πρώιμη ανίχνευση. Οι πιο διαδεδομένες μέθοδοι εξέτασης και διάγνωσης καρκίνου του μαστού είναι η αυτοεξέταση των μαστών από την ίδια τη γυναίκα, η τακτική προληπτική εξέταση του στήθους από το γιατρό καθώς και η πρόληψη μέσω της μεθόδου της μαστογραφίας. Η ανίχνευση του καρκίνου, είναι μια διαδικασία δύσκολη και απαιτεί υψηλό βαθμό αυτοσυγκέντρωσης. Τα νεοπλάσματα αποτελούν παθολογίες και μπορούν να καταταχθούν σε καλοήθη και κακοήθη με ενδιάμεσες διαβαθμίσεις. Το μεγαλύτερο ποσοστό των βιοψιών καταλήγουν τελικά να είναι καλοήθεις. Το νεόπλασμα του μαστού είναι το συχνότερο νεόπλασμα του γυναικείου πληθυσμού. Η διαδικασία συρρίκνωσης της εικόνας, ο αλγόριθμος μετατροπής βάθους των εικονοστοιχείων, ο εμπλουτισμός και η κλιμάκωση της εικόνας αποτελούν κάποιες μεθόδους βελτίωσης της ψηφιακής εικόνας στον τομέα της μαστογραφίας. Περιγράφονται οι τεχνικές ανίχνευσης των ανωμαλιών, με τη βοήθεια των οποίων, μπορούν να εντοπιστούν ανωμαλίες των ιστών στις μαστογραφικές εικόνες. Τέτοιες μορφές ανωμαλιών είναι οι οζώδεις σκιάσεις και οι μικροαποτιτανώσεις. Παρουσιάζονται τα λεγόμενα συστήματα απόφασης και πιο συγκεκριμένα, περιγράφεται ο ορισμός και οι αρχές λειτουργίας των νευρωνικών δικτύων που αποτελούν και τα πιο ευρέως χρησιμοποιούμενα. Τέλος, παρουσιάζεται μια μέθοδος ανίχνευσης νεοπλασιών σε μαστογραφίες, ξεκινώντας από μία γενική εισαγωγή στο σύστημα και στα επίπεδα από τα οποία αποτελείται, και συνεχίζοντας με την ανάλυση των μεθόδων που χρησιμοποιεί. / This assignment is related to neoplasia detection in mammograms. Nowadays, we are aware of the way cancer is created. This fact helps to the improvement of the treatment and also to the reduction of the disease appearance. The key to the successful opposition of the disease is the precocity detection. The most prevalent examination and diagnosis methods of breast cancer are self-examination, regular preventive examination by a doctor and the prevention through the method of mammography. Breast cancer detection, is a difficult procedure and requires a high degree of concentration. Neoplasms represent pathologies and can be categorized in benign and malignant. Breast neoplasm is the most common neoplasm of the female population. The procedure of shrinking the digital image, the depth transduction algorithm of the pixels, the enhancement and the scale of the image, comprise some improvement methods of the digital image in the field of mammography. There is a description of the techniques used for detecting abnormalities of the tissues. Masses and micro-calcifications are examples of that kind of abnormalities. Furthermore, there is a presentation of the well known decision systems, and particularly, definition and principles of functionality of neural networks are described, which are the most widely used. Finally, a new method of neoplasias detection is presented in mammograms, starting from a general introduction of the system and the levels it consists of, and continuing with the analysis of the methods used.

Introduktion: Bröstcancer är den vanligaste cancerform som drabbar kvinnor, tidig upptäckt är en viktig del för en ökad överlevnad i sjukdomen. Variationer i kunskap och utbildning gällande bröstcancer samt attityder kring undersökningsmetoder tenderar att påverka kvinnors tolkning av symptom och deras beslut att söka eller delta i screening/vård. Syfte: Att beskriva kunskaper om bröstcancer och attityder kring mammografiundersökning och självundersökning av bröst hos kvinnor med olika kulturell bakgrund som är bosatta i Sverige. Design: En kvalitativ studie med intervjumetodik. Metod: Studien utfördes med hjälp av semistrukturerade intervjuer med öppna intervjufrågor. Ett strategiskt urval med snöbollsurval användes. Tolv kvinnor i åldersspannet 35-65 år som härstammade från olika asiatiska- och afrikanska länder deltog i studien. Kvalitativ innehållsanalys användes för dataanalys. Resultat: Majoriteten av kvinnorna beskrev att de hade goda allmänna kunskaper om bröstcancer, vilket var mer än den kunskap de hade med sig från sina hemländer. Resultatet gällande attityder till mammografiundersökning och självundersökning visade på att kvinnorna ansåg det viktigt att delta i screeningprogram och att utföra självundersökning men att det inte varit så när de först kommit till Sverige. Kulturella uppfattningar som framkom i studien var att det skulle innebära rädsla för kvinnan att dra skam över sin familj, att sjukdomen i vissa kulturer upplevdes som smittsam samt det kunde upplevas lite som tabu att prata om den egna kroppen.  Slutsats: Det finns fortfarande ett kunskapsbehov kring bröstcancer bland kvinnor med icke europeisk härkomst. Ökad medvetenhet kring bröstcancer hos kvinnor, deras kunskapsnivåer om bland annat självundersökning av bröst kan användas för att uppnå målet med tidig upptäckt av sjukdomen. / Introduction: Breastcancer is the most common type of cancer among women, early detection is important for an increased survival of the desease. Variations in knowledge and education about breastcancer and attitudes towards screeningmethods seem to influate womens perceptions about symthoms and decisions to contact healthcare providers or participate in screening-programmes. Objective: To describe the knowledge about breast cancer and attitudes about mammography and self-breast-examination in women with different cultural backgrounds living in Sweden. Design: A qualitative study using interview methods. Method: The study was conducted by using semi-structured interviews with open-ended questions. A strategic selection of snowball sampling was used. Twelve women in the age range 35-65 years descended from different Asian- and African countries participated in the study. Qualitative content analysis was used for data analysis. Results: The majority of women described that they had good general knowledge about breastcancer, which was more than the knowledge they had brought from their homelands. The results regarding attitudes toward mammography screening and self-examination showed that the women considered it important to participate in screening programs and to perform self-examination but that it might not have been like that when they first came to Sweden. Cultural beliefs that emerged from the study was such that it would mean the fear of an affected woman to shame her family, that the disease in some cultures was seen as contagious, and it could seem somewhat taboo to talk about their own body. Conclusion: There is still a need for knowledge about breast cancer among women with non-European descent. Increased awareness of breast cancer in women, their levels of knowledge about including self-breast-examination can be used to achieve the goal of early detection of the disease.

Doses de radiação de baixa energia podem induzir quebras de dupla fita no DNA assim como também produzir perfis alterados de expressão de genes relacionados a estas lesões. Os danos não reparados ou mal reparados levam a uma maior suscetibilidade à transformação oncogênica já que os efeitos biológicos mais importantes causados pela radiação ionizante são mutação e carcinogênese. As lesões no DNA provocadas pela radiação podem também ocasionar o surgimento micronúcleos e as células podem ser induzidas à apoptose. O objetivo deste trabalho é estudar in vitro a presença de micronúcleos e a apoptose ocasionados por Raios-X de baixa energia. Pretende-se analisar estes efeitos biológicos em relação à energia equivalente à utilizada em exames mamográficos usando duas linhagens estabelecias de células de mama: a MCF-7 (tumoral) e a HB-2 (não-tumoral). As células, em crescimento exponencial, foram irradiadas no equipamento de arranjo experimental de mamografia do LCR/UERJ. A dose de 5Gy na energia de 30 kV foi aplicada com taxa de 0,1 Gy/seg utilizando filtro de 0,03 mm de molibdênio. As irradiações foram realizadas duas vezes, após as irradiações, as células foram incubadas por 4, 24 ou 48 horas e posteriormente coradas com o corante Hoechst33258 para análise em microscopia de fluorescência. Para cada análise, 1000 células foram categorizadas pela morfologia do núcleo. Os resultados mostraram que a HB-2, utilizada neste estudo como célula mamária normal, apresentou maior sensibilidade aos efeitos da radiação, com 37 % das células em apoptose após 4 hs de incubação, enquanto a MCF-7 apresentou 6,5 %. Nas análises após 24 hs foi possível confirmar a radioresistência da MCF-7 tendo sido observadas 11% de células em apoptose no grupo irradiado. Houve um aumento crescente de micronúcleos radioinduzidos nas duas linhagens de acordo com os tempos de incubação. Na análise de 4 hs a HB-2 apresentou 3%, em 24 hs, 8,5% e 48 hs, 11,5 %. Diante destes resultados, foi possível concluir que a energia do feixe de raios-X utilizada na mamografia pode ser capaz de ocasionar aumento de ocorrência de apoptose e geração de micronúcleos nas duas linhagens estudadas / Radiation doses of low-energy can induce double-stranded breaks in DNA as well resulting in altered profiles of gene expression related to these injuries. The damage is not repaired or poorly repaired leading to increased susceptibility to oncogenic transformation since most important biological effects caused by ionizing radiation are mutation and carcinogenesis. The DNA lesions caused by radiation can also provoke the presence of micronuclei and as result cells can be induced to apoptosis. The aim of this work is to perform a preliminary study "in vitro" to identify the presence of micronuclei caused by low energy. X-rays. It is intended analyze these biological effects caused by x-rays with energy equivalent to the ones used in mammography in two very well established breast: cell lines the MCF-7 (tumor) and HB-2 (non-tumor). Cells in exponential growth were irradiated using an experimental arrangement with a mammography tube of the LCR / UERJ. The dose of 5Gy was used for 30 kVp x-rays using 0.03 mm filter molybdenum with a fixed dose rate of 0.1 Gy / sec. The irradiations were repeated twice and. the cells were incubated for 4, 24 or 48 hours and stained with dye Hoechst 33258 for fluorescence microscopy analysis. For each analysis 1000 cells were categorized by the morphology of the nucleus. The results revealed that the HB-2, used in this study as normal mammary cell have showed high sensitivity to the effects of radiation, with 37% of cells undergoing apoptosis after incubation of 4hs, while MCF-7 showed 6.5%. In the 24 hour-analysis it was confirmed the radiation resistance of MCF-7 were it was observed 11% of cells in apoptosis in the irradiated group. There was an increasing number of radiation-induced micronuclei in both cell lines, according to the incubation times. After 4 hours, HB-2 presented 3% of micronuclei, in 24 hours, the experiment reveled 8.5%, and after 48 hours it increased to 11.5%. As result of this study we may conclude that the energy used in mammography is capable to cause an increase in incidence of apoptosis and in the production of micronuclei in both cell lines studied

Introduction : La télémédecine en général et la télé échographie en particulier est une des solutions indéniables au problème de pénurie de médecins spécialistes notamment dans les pays en développement au regard des progrès sans cesse croissant des nouvelles technologies de I‘information et de la communication. Objectif : Concevoir et valider un système de télé expertise échographique temps réel et de télédiagnostic échographique temps différé entre sites expert (CHU) et isolé (hôpitaux périphériques) avec une infrastructure moindre coût accessible même aux pays à faible environnement numérique comme le Togo. Matériels et Méthodes : Une technologie innovante de télétransmission (vidéos échographiques et d’ambiance) temps réel via internet à base de Caméra réseau AXIS 207 et de Serveur vidéo internet AXIS 243 dotée d’adresse IP ou un logiciel d’accès à distance (LogMeln) permet une télé expertise temps réel si le centre isolé dispose d’un échographiste peu expérimenté. / Introduction: Telemedicine generally, and telesonography in particular, is one of undeniable solutions to the problem of specialists’ shortage specially in developing countries with regard to the progress ceaselessly growing of the new technologies of information and communication. Purpose: Design and validate a .system of real time ultrasound tele-expertise, and delayed ultrasound tele-diagnostic between isolated peripherals hospitals and University Hospital center (Expert center) functioning with a lesser infrastructure cost accessible to low digital environment countries like Togo. Materials and Methods: An IP camera and an internet video server are installed in a geographically isolated site equipped with an echograph served by an echographist of first level. Real time tele-expertise (second opinion diagnosis) is possible via internet with an expert center.

O Estado do Rio de Janeiro possui indicadores de produção muito baixos na realização de exames de câncer de mama. Na tentativa de melhorar o acesso aos exames, principalmente em regiões com baixa densidade populacional onde a aquisição de mamógrafos não é custo-efetiva, o uso da mamografia móvel é uma alternativa para aumentar a execução de exames de rastreamento de câncer de mama. O objetivo desta pesquisa é a construção de um modelo computacional para definir a alocação de mamógrafos móveis. O Modelo considera as variáveis associadas com os custos e prazos, indicando quando, onde e por quanto tempo, as unidades móveis de mamografia devem permanecer em cada cidade. O modelo foi construído no software de modelagem e simulação Anylogic, usando técnicas de modelagem baseada em agentes. O principal resultado é determinar o percurso de cada veículo disponível, para oferecer a cobertura desejada em cada cidade. Todas as entradas são parametrizadas, permitindo simular diferentes cenários e fornecer informações importantes para o processo de tomada de decisão. O horizonte de tempo, número de mamógrafos (fixos e móveis), a cobertura desejada da população, a capacidade de produção de cada dispositivo, a adesão da população urbana e rural, entre outras variáveis, foram consideradas no modelo. Os dados da Região Serrana do Rio de Janeiro foram usados nas simulações, onde menos de metade das cidades possuem mamógrafos fixos. Com o modelo proposto foi possível determinar a distribuição de cada dispositivo físico e o número ótimo de unidades móveis de mamografia para oferecer cobertura à totalidade da população no ciclo de dois anos. O número de mamógrafos para oferecer cobertura de toda a população da região poderia ser reduzido pela metade com o modelo de alocação proposto neste trabalho. A utilização de mamografia móvel, em conjunto com a rede existente de mamógrafos fixos, procura maximizar a disponibilização de exames de testes de diagnóstico de câncer de mama no estado do Rio de Janeiro. O desenvolvimento de um modelo de roteamento que aperfeiçoa a cobertura de rastreio do câncer de mama é apresentado como um complemento importante na tentativa de melhorar o acesso à população residente em áreas urbanas e rurais dos municípios. / The Rio de Janeiro State has low indicators in screening exams of breast cancer. As an attempt to improve access to exams, particularly in regions with low population density, where the acquisition of mammography is not cost- effective, the use of mobile mammography is an alternative to increase screening tests for breast cancer. The objective of this research is to build a computer model to define the allocation of mobile mammography. The model considers the variables associated with the costs and deadlines, indicating when, where and how long, the mobile mammography units must remain in each city. The model was built in the modeling and simulation software AnyLogic, using Agent-Based modelling techniques. The main result is to determine the route of each vehicle available, to offer the desired coverage for each city. All inputs are parameterized, enabling simulate different scenarios and providing important information for decision-making. The time horizon, number of mammography devices (fixed and mobile) available, desired coverage of the population, production capacity of each device, adherence of urban and rural population, among others variables, were considered into the model. The tests data came from Mountain Region of the Rio de Janeiro State, where less than half of cities have fixed mammography units. Women need to move to other cities for the examination, which leads to decreased adherence to mammographic screening programs. With the proposed model was possible to determine the distribution of each physical device and the optimum number of mobile mammography units to cover to the entire population in the 2-year cycle. The number of mammography devices to provide coverage to the entire population of the region could be reduced by half with the routing proposed in the model. The use of mobile mammography, together with the existing network of fixed mammography, indicated a possibility to optimize the uptake of breast cancer diagnostic tests in the Rio de Janeiro State. The development of a routing model that optimized the breast cancer screening coverage represent an important complement in an attempt to improve access to mammography exams.

Doses de radiação de baixa energia podem induzir quebras de dupla fita no DNA assim como também produzir perfis alterados de expressão de genes relacionados a estas lesões. Os danos não reparados ou mal reparados levam a uma maior suscetibilidade à transformação oncogênica já que os efeitos biológicos mais importantes causados pela radiação ionizante são mutação e carcinogênese. As lesões no DNA provocadas pela radiação podem também ocasionar o surgimento micronúcleos e as células podem ser induzidas à apoptose. O objetivo deste trabalho é estudar in vitro a presença de micronúcleos e a apoptose ocasionados por Raios-X de baixa energia. Pretende-se analisar estes efeitos biológicos em relação à energia equivalente à utilizada em exames mamográficos usando duas linhagens estabelecias de células de mama: a MCF-7 (tumoral) e a HB-2 (não-tumoral). As células, em crescimento exponencial, foram irradiadas no equipamento de arranjo experimental de mamografia do LCR/UERJ. A dose de 5Gy na energia de 30 kV foi aplicada com taxa de 0,1 Gy/seg utilizando filtro de 0,03 mm de molibdênio. As irradiações foram realizadas duas vezes, após as irradiações, as células foram incubadas por 4, 24 ou 48 horas e posteriormente coradas com o corante Hoechst33258 para análise em microscopia de fluorescência. Para cada análise, 1000 células foram categorizadas pela morfologia do núcleo. Os resultados mostraram que a HB-2, utilizada neste estudo como célula mamária normal, apresentou maior sensibilidade aos efeitos da radiação, com 37 % das células em apoptose após 4 hs de incubação, enquanto a MCF-7 apresentou 6,5 %. Nas análises após 24 hs foi possível confirmar a radioresistência da MCF-7 tendo sido observadas 11% de células em apoptose no grupo irradiado. Houve um aumento crescente de micronúcleos radioinduzidos nas duas linhagens de acordo com os tempos de incubação. Na análise de 4 hs a HB-2 apresentou 3%, em 24 hs, 8,5% e 48 hs, 11,5 %. Diante destes resultados, foi possível concluir que a energia do feixe de raios-X utilizada na mamografia pode ser capaz de ocasionar aumento de ocorrência de apoptose e geração de micronúcleos nas duas linhagens estudadas / Radiation doses of low-energy can induce double-stranded breaks in DNA as well resulting in altered profiles of gene expression related to these injuries. The damage is not repaired or poorly repaired leading to increased susceptibility to oncogenic transformation since most important biological effects caused by ionizing radiation are mutation and carcinogenesis. The DNA lesions caused by radiation can also provoke the presence of micronuclei and as result cells can be induced to apoptosis. The aim of this work is to perform a preliminary study "in vitro" to identify the presence of micronuclei caused by low energy. X-rays. It is intended analyze these biological effects caused by x-rays with energy equivalent to the ones used in mammography in two very well established breast: cell lines the MCF-7 (tumor) and HB-2 (non-tumor). Cells in exponential growth were irradiated using an experimental arrangement with a mammography tube of the LCR / UERJ. The dose of 5Gy was used for 30 kVp x-rays using 0.03 mm filter molybdenum with a fixed dose rate of 0.1 Gy / sec. The irradiations were repeated twice and. the cells were incubated for 4, 24 or 48 hours and stained with dye Hoechst 33258 for fluorescence microscopy analysis. For each analysis 1000 cells were categorized by the morphology of the nucleus. The results revealed that the HB-2, used in this study as normal mammary cell have showed high sensitivity to the effects of radiation, with 37% of cells undergoing apoptosis after incubation of 4hs, while MCF-7 showed 6.5%. In the 24 hour-analysis it was confirmed the radiation resistance of MCF-7 were it was observed 11% of cells in apoptosis in the irradiated group. There was an increasing number of radiation-induced micronuclei in both cell lines, according to the incubation times. After 4 hours, HB-2 presented 3% of micronuclei, in 24 hours, the experiment reveled 8.5%, and after 48 hours it increased to 11.5%. As result of this study we may conclude that the energy used in mammography is capable to cause an increase in incidence of apoptosis and in the production of micronuclei in both cell lines studied

Foram avaliados 507 casos de calcificações quanto as suas características (densidade, morfologia, distribuição, extensão e número) e associação com o câncer de mama.De acordo com os valores preditivos positivos de cada tipo de calcificação elas foram categorizadas pelo sistema BI-RADS em subcategorias 4A (2 a 10%), 4B (10,1 a 30%) e 4C (30,1 a 70,0%) e categoria 5 (acima de 70%). Todas as características se mostraram importantes na diferenciação das calcificações em benignas e malignas, em menor grau a densidade e em maior grau a morfologia e a distribuição. A distribuição linear ou segmentar, e a morfologia pleomorfa ou linear apresentaram as mais altas taxas de malignidade / Five hundred and seven cases of calcificações had been evaluated about its characteristics (density, morphology, distribution, extension and number) and association with the breast cancer. Using the VPP of each type of calcifications they had been categorized by the BI-RADS system in categories 4Â (2 to10%), 4B (10,1 to 30%) and 4C (30,1 to 70.0%) and category 5 (above 70%). All the characteristics had shown importance in the differentiation of the calcificações in benign and malignant, in lesser degree the density and bigger degree the morphology and distribuition. A linear or segmentary distribuition, and the pleomorfic or linear morphology had presented the highest taxes of malignidade