Bakgrund: Forskning visar att barn är känsligare för joniserande strålning än vuxna. Röntgenundersökningar får inte utföras i onödan och nyttan med undersökningen skall överstiga dess risker. Det är viktigt att optimera röntgenundersökningar och så långt som möjligt minimera stråldoser utan att påverka det diagnostiska resultatet, då forskning visar att även låga stråldoser kan ge upphov till DNA-skador och i förlängningen orsaka cancer. Syfte: Att beskriva metoder som optimerar röntgenundersökningar och minskar stråldosen till barn vid konventionell röntgen. Metod: Litteraturstudie vars resultat är baserat på 14 vetenskapliga artiklar funna i databaserna PubMed och CINAHL samt via manuell sökning. Resultat: Det fanns ett flertal metoder och tillvägagångssätt som optimerar röntgenundersökningar och minskar stråldosen till barn vid konventionell röntgen. Metoderna berörde åtgärder i undersökningsrummet, parametrar, filtrering och ny teknik. Konklusion: Röntgensjuksköterskor med kunskap om optimering har goda möjligheter att sänka stråldoser till barn vid konventionell röntgen. / Background: Research shows that children are more sensitive to ionizing radiation than adults. X-ray imaging may not be performed unnecessarily and its necessity must exceed the risks. It is important to optimize the imaging and as far as possible minimize the radiation dose without affecting the diagnostic performance negatively. Research shows that even low doses of radiation can cause DNA damage and ultimately induce cancer. Objective: The aim of this paper was to describe methods that optimize the x-ray examination and reduce radiation doses to children in conventional radiography. Method: A literature study whose results are based on 14 scientific articles found in the databases PubMed and CINAHL and manual searches. Results: There were several methods that optimize the x-ray examination and reduce the radiation doses to children in conventional radiography. These methods concern approaches in the examination room, parameters, filtering and new technology. Conclusion: Radiographers’ with knowledge of optimization have good opportunities to lower radiation doses in x-ray examinations of children in conventional radiography.

Das Ziel dieser Untersuchung ist es, Aspekte der Strukturqualität (technische Untersuchungs- und Bildqualität), Prozessqualität (Angemessenheit der Indikation) und der Ergebnisqualität (Richtigkeit der Befunderhebungen) von Röntgenaufnahmen aus der tierärztlichen Praxis zu erörtern und häufige Fehlerquellen festzustellen. Dazu werden alle Röntgenaufnahmen von Kleintieren, die im Zeitraum von Anfang Dezember 2003 bis Ende Dezember 2004 als Original in die Klinik für Kleintiere der Universität Leipzig gelangen auf praxisrelevante Merkmale der Struktur-, Prozess- und Ergebnisqualität hin untersucht. Die Ermittlung der Daten erfolgt auf subjektiver Grundlage anhand eines Befundbogens durch Konsensbeurteilung von zwei Unter-suchern. Zur Auswertung gelangen 1259 Röntgenaufnahmen aus 600 verschiedenen Untersuchungen. Diese Aufnahmen stammen zu 86,9 % aus den Bundesländern Sachsen, Sachsen-Anhalt und Thüringen von 216 verschiedenen Tierarztpraxen. 80,3 % der untersuchten Tiere sind Hunde, 18,9 % Katzen. In der Gesamtbeurteilung der Bildqualität erweisen sich 48,7 % der Aufnahmen ohne Bean-standung. 29,2 % zeigen geringfügige Mängel, 16,0 % sind bedingt diagnostisch geeignet und 6,1 % sind unzureichend. 22,1 % der ausgewerteten Aufnahmen sind somit mangelhaft. Sie weisen Defizite in der diagnostischen Eignung auf oder sind hierfür ungeeignet. Die wichtigsten Fehlerquellen der Strukturqualität sind Mängel der Lagerung und Projektion, des Bildkontrastes und der Bildschärfe. Abweichungen der Lagerung und Projektion, meist durch nicht winkelgerechte Lagerung des Patienten im Direktstrahl verursacht, sind mit 11,4 % aller Aufnahmen im Vergleich zu anderen Fehlerquellen relativ selten. Die Auswirkungen auf die diagnostische Eignung sind jedoch oft schwerwiegend: 69,9 % der von Mängeln in der Lagerung betroffenen Aufnahmen zeigen Einschränkungen hinsichtlich der diagnostischen Eignung. 33,3 % aller Aufnahmen weisen Abweichungen des Bildkontrastes auf. Die häufigste Ursache dafür ist der Umgang mit verbrauchter Entwicklerlösung, gefolgt von Unter- und Überbelichtung. Betrachtet man die Gesamtheit der Kontrastabweichungen kann festgestellt werden, dass 47,7 % auf Fehler in der Filmentwicklung zurückzuführen sind. Auswirkungen auf die Eignung zur Diagnosestellung sind weniger gravierend als bei Mängeln der Lagerung und Projektion: 35,1 % der von Kontrastabweichungen betroffenen Aufnahmen zeigen Einschränkungen des diagnosti-schen Nutzens. 23,0 % der Aufnahmen sind durch Abweichungen der Bildschärfe gekennzeichnet. Am häufigs-ten ist Bewegungsunschärfe (67,7 % der betroffenen Aufnahmen) zu ermitteln. Weiterhin wer-den oft Materialunschärfe und Unschärfe durch Streustrahlung beobachtet, die auf den falschen Umgang mit dem Streustrahlenraster und der Film-Folien-Kombination zurückzuführen sind. Die Auswirkungen auf die diagnostische Eignung zeigen, dass 29,6 % der Röntgenaufnahmen mit Abweichungen der Bildschärfe Einschränkungen des diagnostischen Nutzens nach sich ziehen. Artefakte, vor allem verursacht durch Kratzer, Risse oder Brüche in Film oder Folie sowie durch Verunreinigungen durch Entwickler-, Fixierlösung oder Wasser, sind bei 20,7 % aller Röntgen-aufnahmen zu finden. Einschränkungen der diagnostischen Eignung ergeben sich dadurch bei 1,2 % der analysierten Aufnahmen. Zur Untersuchung der Prozessqualität wird die Angemessenheit der Indikation ermittelt, die nach RöV § 2a für jede Röntgenaufnahme gegeben sein muss (ANON. 2003a). Eine absolute Indikation kann bei 94,7 % der ausgewerteten Aufnahmen festgestellt werden. Bei knapp der Hälfte aller Aufnahmen dieser Arbeit kann die Ergebnisqualität erörtert werden. Die gestellte radiologische Verdachtsdiagnose ist bei 85,5 % dieser Fälle medizinisch nachvoll-ziehbar. Aus den Ergebnissen dieser Arbeit lässt sich ableiten, dass ein wesentlicher Teil der vorkom-menden Mängel der Bildqualität auf ungenügende Sorgfalt bei der Anfertigung und Verarbeitung der Röntgenaufnahme zurückzuführen ist. Allerdings liegen auch Defizite bei der Interpretation der gewonnenen Information durch die Röntgenuntersuchung vor. Da jeder Anwender ionisierender Strahlen verpflichtet ist, jede unnötige Strahlenexposition von Mensch und Umwelt zu vermeiden, müssen bestehende Defizite in Bezug auf die Anwendung der Projektionsradio-grafie abgebaut werden und die Vermittlung von Wissen und praktischen Fertigkeiten auf diesem Gebiet während der tierärztlichen Ausbildung verbessert werden. Ebenso sollte eine Feh-lerbeseitigung durch Ausnutzung oder Verbesserung der technischen Möglichkeiten erfolgen. Eine erneute Untersuchung zur Qualität von Röntgenaufnahmen in der tierärztlichen Praxis auf der Grundlage dieser Studie erscheint zur Überprüfung der getroffenen Maßnahmen zur Ver-besserung der Bildqualität sinnvoll. / The aim of this study is to evaluate aspects of structural quality (technical examination and im-age quality), quality of the process (adequacy of indication) and the outcome (correctness of findings) of radiographs from the veterinary practice and to indentify frequent radiographic er-rors. For this purpose all radiographs of small animals that are received at the Department of Small Animal Medicine of the University of Leipzig between December 1st 2003 and December 31th 2004 as an original are examined for relevant features of structural quality, process quality and outcome. The data collection is done subjectively based on the consensus examination of the radiographs by two independent examiners. The evaluation includes 1259 radiographs from 600 different examinations. 86.9 % of these images come from the federal states of Germany Saxony, Saxony-Anhalt and Thuringia from 216 different veterinary practices. 80.3 % of the examined animals are dogs, 18.9 % are cats. Concerning the over-all evaluation of the image quality, 48.7 % of the radiographs are without restrictions. Minor faults are detected in 29.2 % of the radiographs, 16.0 % are diagnostically compromised and 6.1 % are insufficient. Thus, 22.1 % of the examined radiographs are unsatis-factory. They show either deficits in their diagnostic suitability or are completely useless. The most important sources of errors are faults in positioning of the patient and the following projec-tion, of image contrast and sharpness. Deviations in positioning and projection, mostly caused by a suboptimal angle in the position of the patient in the x-ray, are with 11.4 % of all radiographs in comparison to other errors relatively rare. However the effect on the diagnostic use is severe: 69.9 % of the images with positioning faults show deficits with regard to the diagnostic suitability. Regarding the contrast of the image, 33.3 % of all radiographs display deficits. The most com-mon cause is the use of exhausted developer, followed by under- and overexposure. Consider-ing the overall deviations of image contrast, 47.7 % are attributed to errors during the x-ray film development. Consequences for the diagnostic use are less serious compared to errors in posi-tioning and projection: 35.1 % of the images with contrast deviations are of limited diagnostic use. 23.0 % of the radiographs are characterized by deviations in the sharpness: motion haziness occurs most frequently (in 67.7 %) of the images concerned. Receptor unsharpness and scat-tered radiation are often observed, caused by improper use of radiographic grids and film-screen combinations. The effects on the diagnostic suitability show that 29.6 % of the radiographs with deviations in the sharpness are of limited diagnostic use. Artifacts, most frequently caused by scratches, tears and breaks of the film or the intensifying screen as well as by splashes of the developing resp. fixation reagent or water, are found on 20.7 % of all radiographs. As a result of artifacts 1.2 % of the radiographs examined show defi-cits in their diagnostic suitability. To evaluate the quality of the process the adequacy of indication is determined, which is required for every radiographic examination according to RöV § 2a (ANON. 2003a). An absolute indication can be found in 94.7 % of all images. The quality of the outcome can be discussed in almost halve of all radiographs. The referral diagnosis is medically plausible in 85.5 % of these cases. The results of this study reveal that a considerable portion of the occurring errors in the image quality are caused by a lack of care during taking and processing of the radiographic images. Deficits in the interpretation of the gained information from the radiographic examination occur as well. Since avoidance of unnecessary exposure of humans and the environment to radiation is a major obligation of every user of ionizing radiation, existing deficits regarding the use of projection radiography should be reduced and the transfer of knowledge and practical capabili-ties in this area during the veterinary training should be improved. Furthermore, the elimination of errors by use or improvement of the technical possibilities is important. A new evaluation of the quality of radiographic images from the veterinary practice on the basis of this study seems useful to examine the effects of the steps taken to improve the image quality.

As dificuldades impostas pela anatomia do sistema de canais radiculares são causas freqüentes de falhas no tratamento endodôntico, principalmente no primeiro molar superior onde a prevalência do canal mésio-palatino (MP) é variável. A condição clínica do dente e a presença de materiais restauradores ou obturadores parecem impor dificuldades para a detecção da presença do canal MP, especialmente quando métodos de imagem são utilizados. Assim, este estudo teve como objetivos: i) avaliar a capacidade diagnóstica da radiografia convencional e da tomografia computadorizada de feixe cônico (TCFC) com diferentes tamanhos de voxel na detecção do canal MP em diferentes situações radiculares; e, ii) avaliar a reprodutibilidade do diagnóstico do canal MP nas mesmas condições. Exames radiográficos e tomográficos (voxel 0.2-mm, 0.25-mm e 0.3-mm), de oitenta e nove molares superiores humanos extraídos foram realizados em três etapas: canal mésio-vestibular (MV) vazio, obturado e após a desobturação. Em seguida, foi realizada a infiltração de corante e diafanização dos dentes. Para a análise estatística utilizou-se o software PASW Statistics 17.0. Para o primeiro objetivo, um examinador, cegado e calibrado, avaliou as imagens para a detecção do canal MP. Como resultados desse estudo pôde-se observar que a TCFC é um método complementar fidedigno para a investigação do canal MP. Em dentes com o canal MV obturado deve-se escolher o protocolo 0.2-mm, entretanto para canais radiculares sem preparo e sem obturação e canais desobturados, a escolha do tamanho de voxel 0.3-mm mostrou-se suficiente para um correto diagnóstico. Para o segundo objetivo proposto, três examinadores, calibrados e cegados, avaliaram as imagens e diagnosticaram a presença ou ausência do canal MP. Na avaliação de reprodutibilidade de diagnóstico, pode-se concluir que a condição do canal foi o fator mais relevante para a variação nos resultados quando comparado ao tamanho do voxel e experiência do examinador. Esses resultados devem ser considerados quando existe a suspeita da presença de um canal MP em um dente onde o re-tratamento endodôntico for necessário, visto que a remoção do material antes da solicitação do exame por imagem reduz os artefatos permitindo a utilização de um protocolo com voxel 0.3-mm, que se mostrou capaz de permitir um correto diagnóstico com menor dose de exposição para o paciente. / The difficulties imposed by the anatomy of the root canal system are a frequent cause of endodontic treatment failures, especially in upper first molars where the prevalence of the second mesiobuccal canal (MB2) is variable. Several methods have been proposed to detect this root canal, but also is important to consider the influence of the clinical condition of the over tooth its the correct diagnosis. Therefore, this study was aimed: i) to assess the diagnostic ability of conventional radiography and CBCT with different voxel sizes in the detection of MB2 in different root conditions; and, ii) to assess the reproducibility of this diagnosis under the same conditions. Radiographs and CBCT scans (0.2-mm, 0.25-mm and 0.3-mm voxel) of eighty-nine extracted human molars were performed in three steps: first mesiobuccal canal (MB1) non filled, filled and after deobturation. Then, samples were cleared. Three examiners, calibrated and blinded, evaluated the images and pointed out the presence or absence of MB2. Statistical analysis was crried on with the PASW Statistics 17.0 software. It was observed that CBCT is a secure complementary method for investigating the presence of MB2. Moreover, when the MB1 canal is filled should be choose the 0.2-mm protocol. The 0.3-mm voxel size images proved to be adequate for a correct diagnosis when the MB1 was non filled or deobturated. In the assessment of diagnostic reproducibility, it can was concluded that the MB1 seemed to be a determinant factor for the result outcome canal condition when compared to the voxel size and the examiner’s experience. These results should be considered when an endodontic re-treatment was indicated, specially when the presence of a MB2 is suspected. The removal of endodontic material prior to request the images exams reduces the presence of artifacts, allowing the use of the 0.3-mm voxel protocol. It was able to allow a correct diagnosis with less patient exposure to the X ray.

As dificuldades impostas pela anatomia do sistema de canais radiculares são causas freqüentes de falhas no tratamento endodôntico, principalmente no primeiro molar superior onde a prevalência do canal mésio-palatino (MP) é variável. A condição clínica do dente e a presença de materiais restauradores ou obturadores parecem impor dificuldades para a detecção da presença do canal MP, especialmente quando métodos de imagem são utilizados. Assim, este estudo teve como objetivos: i) avaliar a capacidade diagnóstica da radiografia convencional e da tomografia computadorizada de feixe cônico (TCFC) com diferentes tamanhos de voxel na detecção do canal MP em diferentes situações radiculares; e, ii) avaliar a reprodutibilidade do diagnóstico do canal MP nas mesmas condições. Exames radiográficos e tomográficos (voxel 0.2-mm, 0.25-mm e 0.3-mm), de oitenta e nove molares superiores humanos extraídos foram realizados em três etapas: canal mésio-vestibular (MV) vazio, obturado e após a desobturação. Em seguida, foi realizada a infiltração de corante e diafanização dos dentes. Para a análise estatística utilizou-se o software PASW Statistics 17.0. Para o primeiro objetivo, um examinador, cegado e calibrado, avaliou as imagens para a detecção do canal MP. Como resultados desse estudo pôde-se observar que a TCFC é um método complementar fidedigno para a investigação do canal MP. Em dentes com o canal MV obturado deve-se escolher o protocolo 0.2-mm, entretanto para canais radiculares sem preparo e sem obturação e canais desobturados, a escolha do tamanho de voxel 0.3-mm mostrou-se suficiente para um correto diagnóstico. Para o segundo objetivo proposto, três examinadores, calibrados e cegados, avaliaram as imagens e diagnosticaram a presença ou ausência do canal MP. Na avaliação de reprodutibilidade de diagnóstico, pode-se concluir que a condição do canal foi o fator mais relevante para a variação nos resultados quando comparado ao tamanho do voxel e experiência do examinador. Esses resultados devem ser considerados quando existe a suspeita da presença de um canal MP em um dente onde o re-tratamento endodôntico for necessário, visto que a remoção do material antes da solicitação do exame por imagem reduz os artefatos permitindo a utilização de um protocolo com voxel 0.3-mm, que se mostrou capaz de permitir um correto diagnóstico com menor dose de exposição para o paciente. / The difficulties imposed by the anatomy of the root canal system are a frequent cause of endodontic treatment failures, especially in upper first molars where the prevalence of the second mesiobuccal canal (MB2) is variable. Several methods have been proposed to detect this root canal, but also is important to consider the influence of the clinical condition of the over tooth its the correct diagnosis. Therefore, this study was aimed: i) to assess the diagnostic ability of conventional radiography and CBCT with different voxel sizes in the detection of MB2 in different root conditions; and, ii) to assess the reproducibility of this diagnosis under the same conditions. Radiographs and CBCT scans (0.2-mm, 0.25-mm and 0.3-mm voxel) of eighty-nine extracted human molars were performed in three steps: first mesiobuccal canal (MB1) non filled, filled and after deobturation. Then, samples were cleared. Three examiners, calibrated and blinded, evaluated the images and pointed out the presence or absence of MB2. Statistical analysis was crried on with the PASW Statistics 17.0 software. It was observed that CBCT is a secure complementary method for investigating the presence of MB2. Moreover, when the MB1 canal is filled should be choose the 0.2-mm protocol. The 0.3-mm voxel size images proved to be adequate for a correct diagnosis when the MB1 was non filled or deobturated. In the assessment of diagnostic reproducibility, it can was concluded that the MB1 seemed to be a determinant factor for the result outcome canal condition when compared to the voxel size and the examiner’s experience. These results should be considered when an endodontic re-treatment was indicated, specially when the presence of a MB2 is suspected. The removal of endodontic material prior to request the images exams reduces the presence of artifacts, allowing the use of the 0.3-mm voxel protocol. It was able to allow a correct diagnosis with less patient exposure to the X ray.

As dificuldades impostas pela anatomia do sistema de canais radiculares são causas freqüentes de falhas no tratamento endodôntico, principalmente no primeiro molar superior onde a prevalência do canal mésio-palatino (MP) é variável. A condição clínica do dente e a presença de materiais restauradores ou obturadores parecem impor dificuldades para a detecção da presença do canal MP, especialmente quando métodos de imagem são utilizados. Assim, este estudo teve como objetivos: i) avaliar a capacidade diagnóstica da radiografia convencional e da tomografia computadorizada de feixe cônico (TCFC) com diferentes tamanhos de voxel na detecção do canal MP em diferentes situações radiculares; e, ii) avaliar a reprodutibilidade do diagnóstico do canal MP nas mesmas condições. Exames radiográficos e tomográficos (voxel 0.2-mm, 0.25-mm e 0.3-mm), de oitenta e nove molares superiores humanos extraídos foram realizados em três etapas: canal mésio-vestibular (MV) vazio, obturado e após a desobturação. Em seguida, foi realizada a infiltração de corante e diafanização dos dentes. Para a análise estatística utilizou-se o software PASW Statistics 17.0. Para o primeiro objetivo, um examinador, cegado e calibrado, avaliou as imagens para a detecção do canal MP. Como resultados desse estudo pôde-se observar que a TCFC é um método complementar fidedigno para a investigação do canal MP. Em dentes com o canal MV obturado deve-se escolher o protocolo 0.2-mm, entretanto para canais radiculares sem preparo e sem obturação e canais desobturados, a escolha do tamanho de voxel 0.3-mm mostrou-se suficiente para um correto diagnóstico. Para o segundo objetivo proposto, três examinadores, calibrados e cegados, avaliaram as imagens e diagnosticaram a presença ou ausência do canal MP. Na avaliação de reprodutibilidade de diagnóstico, pode-se concluir que a condição do canal foi o fator mais relevante para a variação nos resultados quando comparado ao tamanho do voxel e experiência do examinador. Esses resultados devem ser considerados quando existe a suspeita da presença de um canal MP em um dente onde o re-tratamento endodôntico for necessário, visto que a remoção do material antes da solicitação do exame por imagem reduz os artefatos permitindo a utilização de um protocolo com voxel 0.3-mm, que se mostrou capaz de permitir um correto diagnóstico com menor dose de exposição para o paciente. / The difficulties imposed by the anatomy of the root canal system are a frequent cause of endodontic treatment failures, especially in upper first molars where the prevalence of the second mesiobuccal canal (MB2) is variable. Several methods have been proposed to detect this root canal, but also is important to consider the influence of the clinical condition of the over tooth its the correct diagnosis. Therefore, this study was aimed: i) to assess the diagnostic ability of conventional radiography and CBCT with different voxel sizes in the detection of MB2 in different root conditions; and, ii) to assess the reproducibility of this diagnosis under the same conditions. Radiographs and CBCT scans (0.2-mm, 0.25-mm and 0.3-mm voxel) of eighty-nine extracted human molars were performed in three steps: first mesiobuccal canal (MB1) non filled, filled and after deobturation. Then, samples were cleared. Three examiners, calibrated and blinded, evaluated the images and pointed out the presence or absence of MB2. Statistical analysis was crried on with the PASW Statistics 17.0 software. It was observed that CBCT is a secure complementary method for investigating the presence of MB2. Moreover, when the MB1 canal is filled should be choose the 0.2-mm protocol. The 0.3-mm voxel size images proved to be adequate for a correct diagnosis when the MB1 was non filled or deobturated. In the assessment of diagnostic reproducibility, it can was concluded that the MB1 seemed to be a determinant factor for the result outcome canal condition when compared to the voxel size and the examiner’s experience. These results should be considered when an endodontic re-treatment was indicated, specially when the presence of a MB2 is suspected. The removal of endodontic material prior to request the images exams reduces the presence of artifacts, allowing the use of the 0.3-mm voxel protocol. It was able to allow a correct diagnosis with less patient exposure to the X ray.

>Magister Scientiae - MSc / Odontogenic myxoma (OM) is one of the rare odontogenic tumours that affect the maxilo-facial regions. Skeletal myxomas are more common than soft tissue types in the facial regions. Odontogenic myxomas (OM) are non metastasizing tumours and therefore are considered benign. These lesions are known for their distinctive infiltrative nature which makes complete surgical removal a challenging task.Since the tumour occurs inside the bone and can reach a considerable size with little or no clinical manifestation, the radiologic examination remains the main method to determine the size and the extension of the tumour preoperatively.Aim of the study To assess the different imaging techniques which are currently in use for the diagnosis of the odontogenic myxomas.Materials and methods The images were retrieved from the library of the Department of Diagnostics and Radiology at the Tygerberg Oral Health Centre.Initially each of the imaging modalities was assessed independently to describe the imaging features of odontogenic myxoma on conventional radiograph,Computed Tomography (CT) and Magnetic Resonance Image (MRI). Secondly the imaging features of the three techniques were correlated and contrasted to determine the most valuable imaging modality in the diagnosis of the tumour.Results In this study we found that MRI was superior to other modalities in the ability to show and determine the true extension of the tumours. Therefore, MRI distinguished the tumour tissue from the surrounding structures and soft tissues.Myxomas were found to display characteristic patterns of growth on MRI. These patterns include lobulations and/or budding, nodulation and crevices formation.Moreover T2 weighted images deduced the contents of the tumour by emitting different signal intensities from the various components of the tumours.Additionally, characteristic pattern of contrast uptake differentiated the myxomatous, collagenous parts and presumed the nature of the trabeculae whether it is bony or fibrous.CT also showed the tumour and determined the subtle extension of the tumour into the adjacent structures and bone. Expansion and status of the cortical margin were reliably detected on CT. It also determined the pattern of growth in all tumours whether it is lobulation and/or budding, crevices formation or combination of them. In the present study this feature seemed to be a characteristic finding for all the tumours on CT. Moreover CT was able to compare densities of the tumours to surrounding muscles.Conventional radiography (CR) showed great limitations with regard to diagnostic abilities. Although it displayed the existence of the abnormality in all cases,conventional radiograph failed to detect margins and extension in most of the lesions. Therefore conventional radiograph is not reliable for presurgical assessment of the tumour or in differentiation the tumour from other benign and some malignant tumour. Conclusion In spite of the many limitations and shortcomings, conventional radiography remains the preliminary step in the diagnosis process. However digital imaging techniques provide images of great diagnostic value which is especially helpful in the diagnosis of odontogenic myxoma.

Esta pesquisa in vitro, avaliou comparativamente a acurácia do diagnóstico do método radiográfico digital com o método radiográfico convencional, na detecção de lesões de cárie oclusal em molares decíduos. O material foi composto por 55 dentes posteriores decíduos, que apresentavam pigmentações e pelo menos um sítio suspeito de lesão de cárie oclusal, sem restaurações e superfícies sem selantes. As radiografias digitais foram executadas com o sistema Dixi3 (Planmeca, Helsink, Finland) e as radiografias convencionais com o filme Insight (Kodak Eastman Co., EUA), ambas de modo padronizado, em idênticas condições geométricas. As imagens foram avaliadas individualmente por três radiologistas, em ideais condições de interpretação radiográfica e sem acesso aos recursos de manipulação de imagens do sistema digital. Os achados foram classificados de acordo com o seguinte critério: 0 - ausência de radiolucidez no esmalte, 1- radiolucidez confinada ao esmalte, 2- radiolucidez no esmalte até o limite dentina-esmalte, 3- radiolucidez no esmalte e na metade mais externa da dentina, 4- radiolucidez no esmalte alcançando a metade mais interna da dentina. O padrão ouro foi obtido pelo estudo histológico. Os dados foram analisados através do teste de Freidman (P <= 0,05). Os resultados obtidos com os filmes radiográficos convencionais foram similares aos resultados obtidos com as radiografias digitais diretas e o padrão ouro, porém os resultados obtidos com o sistema radiográfico digital foram significativamente menores que o histológico. Nas condições deste estudo, concluímos que o método de radiografia digital subestimou a extensão das lesões de cárie oclusal em molares decíduos. / This in vitro research, evaluated the accuracy of the direct digital radiographic method compared to the conventional radiographic method in the analysis of the extension of occlusal carious lesions in primary molars. The material was composed by 55 primary molars presenting pigmentation and, at least, one suspect site of occlusal carious lesion, these teeth had neither restoration nor surfaces with sealant. Digital radiographs were obtained with the Dixi3 system (Planmeca, Helsink, Finland) and the conventional radiographs with the Insight film (Kodak Eastman Co., USA), both in standard form and identical geometrical conditions. The images were evaluated individually by three radiologists, in ideal conditions for radiographic interpretation and with no access to the resources of imaging manipulation from the digital system. The results were rated according to the following criteria: 0 - absence of radiolucence in the enamel: 1 - radiolucence confined to the enamel, 2 - radiolucence in the enamel to the limit dentine-enamel, 3 - radiolucence in the enamel and in the half outer part of the dentine, 4 - radiolucence in the enamel reaching to the half inner part of the dentine. The gold standard was obtained by histological study. Data were compared by the Friedman`s test (P <= 0.05). The results obtained with the conventional radiographic films were similar to those obtained with both direct digital radiographs and gold standard; however, the results obtained with the digital radiographic system were significantly lower than those observed in the histological analysis. In the conditions of this study, it was concluded that the direct digital radiographic method significantly underestimate the extension of the occlusal caries lesions in primary molars.

Objetivo: Avaliar o desempenho diagnóstico da ressonância magnética (RM) na avaliação da presença de reação periosteal (RP) em sarcomas primários de ossos longos, utilizando a radiologia convencional (RC) como padrão de referência. Materiais e Métodos: Estudo retrospectivo com aprovação do Comitê de Ética Institucional. A partir do Sistema de Informática da Radiologia (RIS) e do Sistema de Arquivo de Imagens do HCRP identificamos retrospectivamente os casos de 42 pacientes consecutivos (idade média de 22 anos, sendo 20 homens, 22 mulheres) que realizaram tratamento de osteossarcoma ou sarcoma de Ewing no HCRP e cujos exames de RM e RC estavam disponíveis para reavaliação. Foram incluídos apenas casos de tumores de ossos longos e com confirmação histopatológica. Três radiologistas musculoesqueléticos avaliaram retrospectivamente a presença ou ausência de RP e identificaram para cada caso a ausência ou presença de cada um dos padrões de RP agressiva nas imagens da RC e da RM: Triângulo de Codman, multilamelada e espiculada. A classificação dos Radiologistas foi realizada de forma independente e às cegas em relação ao diagnóstico definitivo e em relação as demais avaliações realizadas. As leituras das imagens de RM e RC realizadas pelo mesmo observador tiveram um intervalo de pelo menos três meses entre elas. Usamos as leituras dos três observadores para avaliar a confiabilidade interobservador por meio do coeficiente Kappa. Finalmente uma análise consensual das leituras realizadas pelos três observadores tanto para a RC quanto para a RM foi utilizada para calcular o desempenho diagnóstico da ressonância magnética na detecção de RP e na classificação de cada padrão agressivo de RP. O radiologista com maior tempo de experiencia fez a classificação consensual da presença ou ausência de cada subtipo de reação periosteal nos casos em que houve discordância entre os observadores. 8 Resultados: A concordância interobservador para a detecção de RP foi quase perfeita para a RC e substancial a quase perfeita para a RM. A concordância interobservador para a classificação dos diferentes padrões de RP foi moderada a substancial para a presença do triângulo de Codman. A avaliação dos padrões de RP multilamelada e espiculada foi menos consensual entre os radiologistas tanto para RC quanto para a RM. O diagnóstico por RM e RC e a classificação de cada RP agressiva foram estatisticamente associadas com o diagnóstico por RC (p <0,05). A RM mostrou alta especificidade e valor preditivo negativo elevado, mas moderada sensibilidade na detecção de reações periosteais quando comparada com a RC. Conclusão: Nossos resultados sugerem que a detecção de RP por meio da RM e da RC apresenta alta reprodutibilidade. A RM mostrou alta especificidade e sensibilidade moderada para a identificação de RP em comparação com a RC. No entanto, a reprodutibilidade da classificação em diferentes padrões de RP agressivas foi relativamente baixo, tanto para RC quanto para RM em relação às RPs multilameladas e espiculadas. / Objective - To evaluate the diagnostic performance of magnetic resonance imaging (MR) assessing the presence of periosteal reaction (PR) in primary long bone sarcomas using conventional radiography (CR) as the reference standard. Materials and methods After institutional board approval, we retrospectively reviewed the MRI and conventional radiographies of 42 consecutive patients (mean age 22 years, 20 men, 22 women). We included only cases of osteosarcoma or Ewings sarcoma in the long bones with histopathological confirmation. Three experienced musculoskeletal radiologists retrospectively evaluated the presence or absence of periosteal reaction and each pattern of aggressive periosteal reaction in radiographs and MR imaging: Codman triangle, multi layered and spiculated. Radiologists classification was blinded and independent. The readings of the MR images and CR performed by the same observer had an interval of at least three months between them. We use the readings of three observers to assess the interobserver reliability through the Kappa coefficient. Finally a consensus analysis of readings performed by the three observers for both CR and MR was used to calculate the diagnostic performance of MR in detecting PR and classification of each PR aggressive pattern. The radiologist with greater experience made the consensus score of the presence or absence of each periosteal reaction subtype where there was disagreement among observers. 10 Results The interobserver agreement for the detection of PR was almost perfect for the CR and substantial to almost perfect for the MR. The interobserver agreement for the classification of different patterns of PR was moderate to substantial for the presence of Codman triangle. The evaluation of PR multilammelated standards and spiculated was less consensus among radiologists as well for CR as to MR. The diagnostic and the classification of each aggressive PR with MR imaging and with CR were statistically associated with the diagnosis by CR (p <0.05). MR showed high specificity and high negative predictive value, but moderate sensitivity in detecting periosteal reactions when compared to the CR. Conclusions Our results suggest that detection of PR through MR and CR has high reproducibility. MRI showed high specificity and moderate sensitivity for the identification of PR compared to CR. However, the reproducibility of the classification into different patterns of aggressive PRs was relatively low for both CR and for MR regarding the multilamellated and spiculated PRs.

Esta pesquisa in vitro, avaliou comparativamente a acurácia do diagnóstico do método radiográfico digital com o método radiográfico convencional, na detecção de lesões de cárie oclusal em molares decíduos. O material foi composto por 55 dentes posteriores decíduos, que apresentavam pigmentações e pelo menos um sítio suspeito de lesão de cárie oclusal, sem restaurações e superfícies sem selantes. As radiografias digitais foram executadas com o sistema Dixi3 (Planmeca, Helsink, Finland) e as radiografias convencionais com o filme Insight (Kodak Eastman Co., EUA), ambas de modo padronizado, em idênticas condições geométricas. As imagens foram avaliadas individualmente por três radiologistas, em ideais condições de interpretação radiográfica e sem acesso aos recursos de manipulação de imagens do sistema digital. Os achados foram classificados de acordo com o seguinte critério: 0 - ausência de radiolucidez no esmalte, 1- radiolucidez confinada ao esmalte, 2- radiolucidez no esmalte até o limite dentina-esmalte, 3- radiolucidez no esmalte e na metade mais externa da dentina, 4- radiolucidez no esmalte alcançando a metade mais interna da dentina. O padrão ouro foi obtido pelo estudo histológico. Os dados foram analisados através do teste de Freidman (P <= 0,05). Os resultados obtidos com os filmes radiográficos convencionais foram similares aos resultados obtidos com as radiografias digitais diretas e o padrão ouro, porém os resultados obtidos com o sistema radiográfico digital foram significativamente menores que o histológico. Nas condições deste estudo, concluímos que o método de radiografia digital subestimou a extensão das lesões de cárie oclusal em molares decíduos. / This in vitro research, evaluated the accuracy of the direct digital radiographic method compared to the conventional radiographic method in the analysis of the extension of occlusal carious lesions in primary molars. The material was composed by 55 primary molars presenting pigmentation and, at least, one suspect site of occlusal carious lesion, these teeth had neither restoration nor surfaces with sealant. Digital radiographs were obtained with the Dixi3 system (Planmeca, Helsink, Finland) and the conventional radiographs with the Insight film (Kodak Eastman Co., USA), both in standard form and identical geometrical conditions. The images were evaluated individually by three radiologists, in ideal conditions for radiographic interpretation and with no access to the resources of imaging manipulation from the digital system. The results were rated according to the following criteria: 0 - absence of radiolucence in the enamel: 1 - radiolucence confined to the enamel, 2 - radiolucence in the enamel to the limit dentine-enamel, 3 - radiolucence in the enamel and in the half outer part of the dentine, 4 - radiolucence in the enamel reaching to the half inner part of the dentine. The gold standard was obtained by histological study. Data were compared by the Friedman`s test (P <= 0.05). The results obtained with the conventional radiographic films were similar to those obtained with both direct digital radiographs and gold standard; however, the results obtained with the digital radiographic system were significantly lower than those observed in the histological analysis. In the conditions of this study, it was concluded that the direct digital radiographic method significantly underestimate the extension of the occlusal caries lesions in primary molars.

Objetivo: Avaliar o desempenho diagnóstico da ressonância magnética (RM) na avaliação da presença de reação periosteal (RP) em sarcomas primários de ossos longos, utilizando a radiologia convencional (RC) como padrão de referência. Materiais e Métodos: Estudo retrospectivo com aprovação do Comitê de Ética Institucional. A partir do Sistema de Informática da Radiologia (RIS) e do Sistema de Arquivo de Imagens do HCRP identificamos retrospectivamente os casos de 42 pacientes consecutivos (idade média de 22 anos, sendo 20 homens, 22 mulheres) que realizaram tratamento de osteossarcoma ou sarcoma de Ewing no HCRP e cujos exames de RM e RC estavam disponíveis para reavaliação. Foram incluídos apenas casos de tumores de ossos longos e com confirmação histopatológica. Três radiologistas musculoesqueléticos avaliaram retrospectivamente a presença ou ausência de RP e identificaram para cada caso a ausência ou presença de cada um dos padrões de RP agressiva nas imagens da RC e da RM: Triângulo de Codman, multilamelada e espiculada. A classificação dos Radiologistas foi realizada de forma independente e às cegas em relação ao diagnóstico definitivo e em relação as demais avaliações realizadas. As leituras das imagens de RM e RC realizadas pelo mesmo observador tiveram um intervalo de pelo menos três meses entre elas. Usamos as leituras dos três observadores para avaliar a confiabilidade interobservador por meio do coeficiente Kappa. Finalmente uma análise consensual das leituras realizadas pelos três observadores tanto para a RC quanto para a RM foi utilizada para calcular o desempenho diagnóstico da ressonância magnética na detecção de RP e na classificação de cada padrão agressivo de RP. O radiologista com maior tempo de experiencia fez a classificação consensual da presença ou ausência de cada subtipo de reação periosteal nos casos em que houve discordância entre os observadores. 8 Resultados: A concordância interobservador para a detecção de RP foi quase perfeita para a RC e substancial a quase perfeita para a RM. A concordância interobservador para a classificação dos diferentes padrões de RP foi moderada a substancial para a presença do triângulo de Codman. A avaliação dos padrões de RP multilamelada e espiculada foi menos consensual entre os radiologistas tanto para RC quanto para a RM. O diagnóstico por RM e RC e a classificação de cada RP agressiva foram estatisticamente associadas com o diagnóstico por RC (p <0,05). A RM mostrou alta especificidade e valor preditivo negativo elevado, mas moderada sensibilidade na detecção de reações periosteais quando comparada com a RC. Conclusão: Nossos resultados sugerem que a detecção de RP por meio da RM e da RC apresenta alta reprodutibilidade. A RM mostrou alta especificidade e sensibilidade moderada para a identificação de RP em comparação com a RC. No entanto, a reprodutibilidade da classificação em diferentes padrões de RP agressivas foi relativamente baixo, tanto para RC quanto para RM em relação às RPs multilameladas e espiculadas. / Objective - To evaluate the diagnostic performance of magnetic resonance imaging (MR) assessing the presence of periosteal reaction (PR) in primary long bone sarcomas using conventional radiography (CR) as the reference standard. Materials and methods After institutional board approval, we retrospectively reviewed the MRI and conventional radiographies of 42 consecutive patients (mean age 22 years, 20 men, 22 women). We included only cases of osteosarcoma or Ewings sarcoma in the long bones with histopathological confirmation. Three experienced musculoskeletal radiologists retrospectively evaluated the presence or absence of periosteal reaction and each pattern of aggressive periosteal reaction in radiographs and MR imaging: Codman triangle, multi layered and spiculated. Radiologists classification was blinded and independent. The readings of the MR images and CR performed by the same observer had an interval of at least three months between them. We use the readings of three observers to assess the interobserver reliability through the Kappa coefficient. Finally a consensus analysis of readings performed by the three observers for both CR and MR was used to calculate the diagnostic performance of MR in detecting PR and classification of each PR aggressive pattern. The radiologist with greater experience made the consensus score of the presence or absence of each periosteal reaction subtype where there was disagreement among observers. 10 Results The interobserver agreement for the detection of PR was almost perfect for the CR and substantial to almost perfect for the MR. The interobserver agreement for the classification of different patterns of PR was moderate to substantial for the presence of Codman triangle. The evaluation of PR multilammelated standards and spiculated was less consensus among radiologists as well for CR as to MR. The diagnostic and the classification of each aggressive PR with MR imaging and with CR were statistically associated with the diagnosis by CR (p <0.05). MR showed high specificity and high negative predictive value, but moderate sensitivity in detecting periosteal reactions when compared to the CR. Conclusions Our results suggest that detection of PR through MR and CR has high reproducibility. MRI showed high specificity and moderate sensitivity for the identification of PR compared to CR. However, the reproducibility of the classification into different patterns of aggressive PRs was relatively low for both CR and for MR regarding the multilamellated and spiculated PRs.