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Shi, Lin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 171-185). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

This thesis presents a three-dimensional computed tomography (3D-CT) analysis of craniofacial morphology and growth changes in Malaysian Malay subjects. A large number of CT scans (n=205) from birth to adulthood were gathered for this purpose. CT scans were obtained using a GE Lightspeed Plus Scanner. Craniofacial morphology has been analysed based on cephalometric landmarks located in three-dimensions, using specially-designed computer software. The main aims were to produce new 3D normative reference data for selected craniofacial variables in Malaysian Malays and to study growth changes in different craniofacial regions. The specific areas of investigation included: 1. Construction of craniofacial growth references (in tabular and graphical formats) for Malaysian Malays; 2. Quantitative analysis of growth changes in the craniofacial complex using linear and angular measurements derived from landmark data; 3. Comparison of craniofacial measurements between males and females to determine the extent of sexual dimorphism; 4. Quantitative analysis of the nature and extent of directional asymmetry of selected craniofacial regions; 5. Comparisons of selected variables with published data from other ethnic groups. Craniofacial morphology and growth changes were analysed using 3D osseous landmarks. A computer program, PERSONA, was used to locate and analyse the three-dimensional cephalometric landmarks. The accuracy of landmark location was assessed using double determinations. Selected measurements were derived from the landmark data to describe the morphology of different craniofacial regions, e.g. facial skeleton, cranial base and cranial vault. Normative reference data for a large number of variables covering the skull, cranial base and face at selected age categories for males and females were constructed. These data were presented in tables and scatter plots of variables against age. From the normative data collected, patterns of growth changes of different craniofacial regions in three-dimensions were also investigated. Generally, each craniofacial region showed a unique growth pattern as observed from differential growth patterns. All measurements showed size increase from infancy to adulthood. Periods of increased size differences were also noted for most variables in all regions that corresponded to the timing of mid- and adolescent growth spurts. These extensive normative reference data, specific for age categories and sexes, provide normal references against which the craniofacial morphology of individuals with craniofacial abnormalities can be compared. Clinical applications of this quantitative approach to the craniofacial skeleton should facilitate the management of craniofacial abnormalities. Following the construction of normative data and description of growth changes for different craniofacial regions, intra-populational differences were studied. This included analysis of sexual dimorphism of the craniofacial structures and an investigation of asymmetry between paired left and right measurements. Sexual dimorphism was observed for linear variables in this study. Differences in size between males and females were not very obvious during infancy as only a few variables showed significant differences. The number of variables that showed sexual dimorphism in size increased from infancy to adulthood. Sexual dimorphism in the craniofacial region was most evident during adulthood with 46% of variables displaying significant differences between the sexes. During infancy, only 3% of the variables showed significant size differences between the sexes, increasing to 7% during childhood. Magnitudes of sexual dimorphism were calculated to highlight the pattern of dimorphism in different craniofacial regions and across different ages. A small degree of directional asymmetry was noted in all of the craniofacial regions investigated. Asymmetry analysis revealed that the cranial base, face and mandible tended to be larger on the right side than the left. Other regions exhibited asymmetry but without any clear trend in direction. Asymmetry percentages were also calculated to enable the patterns and magnitudes of asymmetry in different craniofacial regions to be compared. Generally, the amount of asymmetry exhibited in the craniofacial structures for Malaysian Malays was small. Having established that differences existed within the Malay sample, craniofacial data for Malays were compared with published data for two Caucasian populations. This analysis revealed that differences exist in craniofacial morphology between different ethnic groups. Some of the differences can be discerned from childhood but many variables only display differences during adulthood. Craniofacial structures tended to be smaller in Malays than in Caucasians. The intent of this investigation has been to provide clinicians with normative values of measurements that will be useful in diagnosis, treatment planning and post-operative care of patients with craniofacial abnormalities. Important treatment goals include producing balanced cranial and facial form to approximate that of unaffected people and also improving the quality of life of patients. Therefore, it is important for clinicians to be able to recognise the nature and extent of normal variation in craniofacial structures and also appreciate the growth changes that may occur over time, before investigating these changes in patients with craniofacial abnormalities. Comparisons of measurements of affected patients with well-characterised referent data can facilitate diagnosis and overall patient management. Moreover, quantification based on three-dimensional data provides new insights into craniofacial growth changes and morphology compared with conventional 2D approaches. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1280892 / Thesis (Ph.D.) -- Dental School, 2007.

Cranial and post-cranial non-metric variants are used to examine 664 individuals from the Grasshopper Pueblo skeletal series. The pueblo was inhabited from the 12th to the 14th century A.D. A variety of statistical analyses are utilized to examine patterns of morphological variation which can be used to assess whether biological differences can be demonstrated on the basis of non-metric trait frequencies. All traits are examined for frequency of occurrence, and trait frequencies are then tested to determine if they vary by side of the body, sex, age, type of cranial deformation or association with one another. A series of skeletons are re-tested in order to test intra- and inter-observer reliability. A refined list of traits developed from these analyses is then used to examine trait frequency distributions among the three major room blocks at the site. The full battery of traits used in this study are found to be free of the effects of side of the body, sex, type of cranial deformation and associations with one another, but are affected slightly by age. Intra- and inter-rater reliability are low for this sample and battery of traits. The conclusion is that individuals from the Pueblo do not aggregate into groups which are distinguishable on the basis of non-metric traits.

This study was undertaken to identify the landmarks that would provide the most reliable and predictable indicators of the position of the supraorbital, infraorbital, mental and mandibular foramina in human skulls of Hokien, Hylam, Indian and British populations of ranging ages, which would provide clinicians with suitable modifications in technique to accommodate these variations. Measurements were taken using both electronic digital callipers and 3D laser scanning. Electronic digital calliper measurements were made to estimate how far each foramen was from specific anatomical landmarks on the skulls. An apparatus was developed to position the skulls securely so that the measurement points could be accurately identified, then an electronic digital calliper was used to measure the distance between the defined points. In addition, the same skulls were also scanned using a FastSCAN™ Polhemus Scorpion™ handheld laser scanner, and imported into 3D modelling software (FreeForm Modelling Plus™). This 3D software integrates a PHANYOM™ desktop arm and a haptic force feedback device that provides the user with a sense of touch. Accordingly, with the “Ruler” tool, the measurements between various foramina and defined anatomical landmarks were measured. Measurements made by electronic digital calliper were compared statistically with those made using the 3D scanning method, and overall there was good correlation between the two, indicating that 3D scanning could be used as an alternative method. With regard to age changes in the skulls, the ages of the Hokien and Hylam groups were known, having been recorded from death records, but the Indian and British skulls were not of known age. In a preliminary study the known age skulls were used to validate the methods of Miles (1962) and Brothwell (1981) who aged skulls using tooth wear patterns. The decision was taken to use the Brothwell chart for the assessment of age in the Indian and British skulls in the main study. For each of the four population groups, intra-population comparisons of the measurements were made between right and left sides, and between skulls of young and old individuals, also inter-population comparisons between ipsilateral measurements were made. The correlation between the obtuseness of the mandibular angle and the ipsilateral measurement from the mental foramen to the posterior border of the mandible were made on both sides of the skulls of each population group. Non-significant differences were found between the measurements on right and left sides for the skulls of all populations. There were significant differences between some ipsilateral measurements but although there were statistically significant, they were not considered to be clinically significant. There were no significant differences between ipsilateral measurements with increasing age of the skulls. Also there were weak correlations between the obtuseness of the mandibular angle and the ipsilateral measurement from the mental foramen to the posterior border of the mandible on both sides of the skulls of each population group. There were good statistically agreements between the electronic digital calliper and 3D laser scanning measurements in all groups and the two methods may be used interchangeably. However 3D scanning is a digital process and therefore the scans could be accessed remotely, either across the internet or by CD.

Thesis (MSc)--Stellenbosch University, 1998 / Stellenbosch University. Faculty of Science. Dept. of Botany & Zoology. / ENGLISH ABSTRACT: There has been a long-standing need to systematically analyze and classify South African fossil Lacertilia. Although extensive assemblages of fossil lizard and amphibian material from Langebaan on the West Coast and elsewhere exist in museum collections, the fragmentary nature of the material has largely prevented in-depth analyses and identification. In this comparative study the skulls and lower jaws of 7 lizard genera, representing the six extant South African families, were disassembled and the bones analyzed individually. The aim was to compile a comparative database of each bone against which current and future fossil finds could be matched. Detailed descriptions of the isolated elements were given. The results showed that despite some intra-generic variation, unique structural differences do exist in individual bones which may be utilized in the taxonomic assessment of fragmentary fossil material. / AFRIKAANSE OPSOMMING: Daar bestaan lank reeds 'n behoefte vir die sistematiese analise en klassifisering van fossielmateriaal van Suid-Afrikaanse Lacertilia. Alhoewel uitgebreide versamelings van akkedis- en amfibier-fossiele van Langebaan aan die Weskus en elders in museums bestaan, het die fragmentariese aard van die materiaal grootliks diepgaande analises en identifikasie belemmer In hierdie vergelykende studie is die skedels en onderkake van 7 akkedisgenera, wat die ses resente Suid-Afrikaanse families verteenwoordig, gedisartikuleer en elke been individueel geanaliseer. Die doel was om 'n vergelykende databasis van elke been saam te stel waarmee huidige en toekomstige fossielvondse vergelyk kan word. Gedetaileerde beskrywings van die ge'isoleerde elemente word gegee. Die resultate toon dat desondanks 'n mate van intra-generiese variasie, unieke strukturele verskille tussen individuele bene weI bestaan en dat hierdie verskille gebruik kan word om fossielfragmente taksonomies te analiseer.

Dissertation (PhD)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Introduction: Fetal alcohol syndrome (FAS) consists of multi-system abnormalities and is caused by the excessive intake of alcohol during pregnancy. The teratogenic effect of alcohol on the human fetus has now been established beyond reasonable doubt and FAS is the most important human teratogenic condition known today. The syndrome, first described by Lemoine in1968 in the French literature and in the English literature by Jones and Smith in 1973, has since been corroborated by numerous animal and human studies. This study has grown out of several epidemiological, prenatal and infant studies in areas of the Western Cape that are currently being undertaken by the Foundation for Alcohol Related Research (FARR). Preliminary data from studies in Wellington have confirmed that a significant proportion of school-entry children have FAS. The prevalence ofF AS in this community exceeds that for Down syndrome by a factor of30 times. The frequency ofFAS in high-risk populations of the Western Cape is the highest reported anywhere in the world. With this background, and the paucity of FAS literature related to dentistry, the aim of this study was to determine the craniofacial and oral manifestations ofF AS in a sample of school-going children in the Western Cape. Methodology: This study is a descriptive, case-control, cross-sectional study using a random cluster sampling method. On the day of examination, children were weighed, and their height and head circumference were measured. They then had photographs and radiographs taken, followed by an oral examination. For each child, the following information was recorded on the data capture sheet: date of birth, gender, head circumference, weight and height, enamel opacities, dental fluorosis, plaque index, gingival bleeding index, dentition status, oral mucosal lesions and dentofacial anomalies. Results: The total sample of90 children with diagnosed FAS and 90 controls, were matched for age, gender and social class. There were no significant age differences between the two groups (p=0.3363) and the mean ages were 8.9 and 9.1 for the FAS and control groups respectively. Head circumference (HC) differed significantly between the two groups (p<O.OOO 1) and the three photographic diagnostic measurements were all influenced by head circumference. The prevalence of enamel opacities between FAS and controls was not significantly different and averaged around 15% for both groups. The opacities were found largely in the maxillary central incisor and lower first molar teeth. More than three quarters of both the cases and the controls demonstrated the presence of plaque and almost two thirds demonstrated gingival bleeding on probing. FAS patients had statistically significantly (p<O.OO 1) more dentofacial anomalies than the controls. The mean dmft score for the FAS sample was slightly higher, though not significantly different from that of the controls and the decayed component (d) made up the largest part of the index in both groups. None of the FAS children had any missing or filled teeth, and in the case of the controls these were also rarely found. Thirty nine children (21.67%) of the total sample were caries-free. Discussion: This study represents one of the largest sample sizes documenting the craniofacial and oral and dental manifestations of the FAS to date. Forty two per cent of the FAS sample manifested growth retardation and this was statistically significant (p<O.OOOl) when compared to their controls. Analysis of the face using anthropometry supports many of the previous clinical descriptions of the effects of neonatal alcohol exposure and offers some new perspectives on the FAS facial phenotype. The characteristic dysmorphic facial features found included ptosis of the upper eyelids, epicanthic folds, short upturned nose, thin vermillion border of the upper lip and a smooth philtrum. Overall the analysis of the caries data for this study in respect of differences between cases and controls was found to be unremarkable. The lack of difference in the primary and permanent dentitions between the cases and controls could have been anticipated in this population due to the high prevalence of dental caries among children from the Western Cape. The FAS children showed significantly lower dental ages when compared to the controls. Dental maturation has previously been shown to be mildly, but consistently, delayed in children with delayed development and therefore this is a not surprising finding for the FAS children in this study. Differences between skeletal age and chronological age were noted for both boys and girls, but as a whole, in the present study groups (FAS and controls) showed little variation in skeletal development. Measurements related to the face height and mandibular size appear to be the most important in distinguishing the FAS children from the controls. Most (5 out of8) of the discriminating linear measurements studied lie in the front of the skull area. Most of the discriminating measurements are vertical measurements and only two of the measurements are lines between soft tissue points. When comparing the photographic analyses of the facial features versus the cephalometric assessments; the four facial features most typical of aF AS child had a Positive Predictive Value (PPV) of92% and a Negative Predictive Value (NPV) of90% and the eight linear measurements from the cephalometric analyses had a PPV of 92% and a NPV of 95%. One can therefore conclude that the external facial features are probably more reliable in discriminating between the two groups than the cephalometric measures. For further analyses, other models where a single angular measurement explains a combination of linear measurements need to be investigated. This might further improve the discriminating abilities of the cephalometric measurements as a whole. Conclusions: This study has shown the importance of the oral and craniofacial features ofFAS. FAS can no longer be viewed as just a rare and peculiar childhood disorder. Awareness and recognition of children with FAS is important so that they can be correctly diagnosed and referred appropriately. Prevention of the secondary disabilities and most importantly, the prevention of FAS in subsequent programmes can be planned. The dentist who treats children with FAS must recognise that such patients might be emotionally and mentally handicapped and may make treatment difficult and there may be a need for the child to be treated with behaviour modification and/or premedication before restorative treatment. The dentist should also be aware of the need for an accurate medical history, and possible medical consultations, before treatment can be undertaken safely. / AFRIKAANSE OPSOMMING: Fetale alkoholsindroom (FAS) bestaan uit multisisteem abnormaliteite en word veroorsaak deur oormatige inname van alkohol tydens swangerskap. Die teratogeniese uitwerking van alkoholop die menslike fetus word nie meer betwyfel nie en FAS is die belangrikste menslike teratogeniese toestand tans bekend. Die sindroom, soos aanvanklik deur Jones en Smith in 1973 beskryf, is sedertdien deur vele studies op mens en dier bevestig. Hierdie studie het gegroei uit vele epidemiologiese-, prenatale- en kleuterstudies in dele van die Weskaap wat tans onderneem word deur die Stigting vir Alkoholverwante Navorsing. Voorlopige data van die studies in Wellington bevestig dat 'n betekenisvolle deel van skoolbeginners FAS het. Die prevalensie van FAS in hierdie gemeenskap oortref dié van Down se sindroom met 'n faktor van 30. Die frekwensie van FAS in die Weskaap is die hoogste wat in die wêreld gerapporteer is. Met hierdie agtergrond, en die skaarste aan FAS literatuur wat op tandheelkunde betrekking het, was die doel van hierdie studie om die kraniofasiale en mondmanifestasies van fetale alkoholsindroom in 'n monster van skoolkinders in die Weskaap te ondersoek. Metodologie: Hierdie studie was 'n beskrywende, gevallebeheerde deursneestudie waarin 'n lukrake gebondelde monstermetode gebruik is. Op die dag van die ondersoek is die kinders geweeg en hulle lengte en kopomtrek bepaal. Hierna is foto's en x-straalopnames geneem, gevolg deur 'n mondondersoek. Die volgende inligting is vir elke kind aangeteken: geboortedatum, geslag, kopomtrek, massa en lengte, glasuur-opasiteite, tandfluorose, plaakindeks, gingivale bloedingsindeks, gebitstatus, mukosale letsels en dentofasiale anomalieë. Resultate: Die totale monster, bestaande uit 90 kinders met gediagnoseerde fetale alkoholsindroom en 90 bypassende kontroles, is vergelyk ten opsigte van ouderdom, geslag en sosiale klas. Daar was geen betekenisvolle ouderdomsverskille tussen die twee groepe nie (p- =0.3363). Kopomtrek het betekenisvol tussen die twee groepe verskil (p<0.0001), en die drie fotografiese diagnostiese afmetings is almal beïnvloed deur kopomtrek. Die prevalensie van glasuur-opasiteite tussen die FAS- en kontrolegroep was nie betekenisvol nie en het rondom 15% vir beide gewissel. Die opasiteite is hoofsaaklik gesien in maksillêre sentrale snytande en mandibulêre eerste molare. Meer as driekwart van beide groepe het plaak getoon, en byna tweederdes het gingivale bloeding met sondering gehad. Die gevallegroep het statisties betekenisvol meer (p<O.OO1) dentofasiale anomalieë getoon. Die gemiddelde dmft telling vir die FAS groep was effens hoër, alhoewel nie betekenisvol nie, as die kontrolegroep, en die "delayed" (vertraagde erupsie) komponent (d) het die grootste deel van die indeks uitgemaak in beide groepe. Geen van die FAS kinders het enige afwesige tande (m) of hers telde tande (f) gehad nie, soos ook gevind in die kontrolegroep. Nege-en-dertig kinders (21.67%) van die totale monster was kariesvry. Bespreking: Hierdie studie verteenwoordig een van die grootste monstergroottes tot op datum waarin ondersoek ingestel is na die kraniofasiale en mond- en tandmanifestasies van die fetale alkoholsindroom. Twee-en-veertig persent van die FAS monster het vertraagde groei getoon en dit was statisties-betekenisvol (p<O.OOOl)vergeleke met die kontrolegroep. Antropometriese analise van die gesig steun die vele kliniese beskrywings van neonatale blootstelling aan alkohol, en bied ook nuwe perspektiewe op die FAS gesigsfenotipe. Die kenmerkende dismorfiese gesigseienskappe wat gevind word, sluit ptose van die boonste ooglede, epikantusvoue, kort opgedraaide neus, dun vermiljoen rand van die bolip en 'n gladde filtrum in. In die geheel was die analise van die karies data ten opsigte van verskille tussen gevalle en kontroles onopvallend. Die afwesigheid van 'n verskil in die primêre en sekondêre gebitte in die gevalle en kontroles kon in hierdie bevolking verwag gewees het as gevolg van die hoë voorkoms van tandkaries onder kinders in die Weskaap. Die FAS kinders het betekenisvol-laer gebitouderdomme gehad as die kontrolegroep. Gebitmaturasie is in geringe maar deurlopende mate vertraag in kinders met vertraagde ontwikkelings, soos voorheen al getoon, en is daarom nie verbasend vir die FAS kinders in hierdie studie nie. Verskille tussen skeletale ouderdom en chronologiese ouderdom is gevind in beide seuns en dogters, maar in die geheel het dié huidige groepe (FAS en kontroles) min variasie in skeletale ontwikkeling getoon. Dit wil voorkom of afmetings wat verband hou met die gesigshoogte en grootte van die mandibula die belangrikste is om FAS kinders van die kontrolegroep te onderskei. Meeste (5 uit 8) van die diskriminerende lineêre afmetings wat bestudeer is, lê op die voorkant van die skedel. Die meeste is vertikale afmetings, terwyl slegs twee lyne tussen sagte weefsel punte. Waneer die fotografiese analises van die gesigseienskappe vergelyk word met die sefalometriese waarnemings, word gevind dat die vier gesigseienskappe tipies van 'n FAS kind 'n Positiewe Voorspelbare Waarde (PVW) van 92% en 'n Negatiewe Voorspelbare Waarde (NVW) van 90% het, en die agt lineêre afmetings vanaf die sefalometriese analise 'n PVW van 92% en 'n NPV van 95% het. Daar kan dus afgelei word dat die eksterne gesigseienskappe waarskynlik meer betroubaar is om te onderskei tussen die twee groepe. Vir verdere analise behoort ander modelle waar 'n enkel hoekige afmeting 'n kombinasie van lineêre afmetings verduidelik, ondersoek te word. Dit mag die diskriminerende vermoëns van sefalometriese afmetings in die geheel verder bevorder. Gevolgtrekking: Hierdie studie het die belang van orale en kraniofasiale eienskappe van FAS getoon. Die toestand kan nie langer as 'n seldsame en eienaardige aandoening van kinders beskou word nie, en bewustheid en herkenning van fetale alkoholsindroom pasiënte is belangrik sodat hulle korrek gediagnoseer en op gepaste wyse verwys kan word. Die tandarts wat FAS pasiënte behandel, moet besef dat sulke pasiënte emosioneel en geestelik belemmer mag wees en dus hantering en behandeling bemoeilik. Daar mag 'n behoefte ontstaan vir gedragsmodifikasie enlofpremedikasie voor herstellende behandeling. Verder moet die tandarts bewus wees van die behoefte aan 'n akkurate mediese geskiedenis, en moontlik konsultasie met 'n geneesheer, voor behandeling veilig ingestel kan word.

published_or_final_version / abstract / Biochemistry / Doctoral / Doctor of Philosophy

Depuis le début des années 1990, l'imagerie de l'oreille et de la base du crâne s'est considérablement développée. Des pathologies récentes, mal connues ont été explorées en imagerie, en particulier en IRM. L'objectif de mes travaux de recherche, a été de développer des séquences Haute Résolution (HR) sur l'oreille et la base du crâne permettant une analyse sémiologique fine et une caractérisation de ces différentes pathologies dans l’objectif d’une prise en charge plus adaptée. Le début de mes travaux a été orienté vers le conduit auditif interne. Mon but initial a été de mettre point et de développer une séquence 3 HR T2 sur l'oreille interne et le conduit auditif interne ainsi qu’une séquence spin écho T1 HR en coupes fines. Ces séquences ont permis l’analyse précise de l'extension des schwannomes vestibulaires dans le fond du conduit auditif interne. Cette étude a permis de dégager des critères intéressants en imagerie dans le choix thérapeutique (chirurgie versus radio-chirurgie) et dans le choix de la voie d'abord chirurgicale. Mon travail s’est également orienté vers le développement des séquences de diffusion en base du crâne, le but était de développer une séquence de diffusion HR dans le suivi des cholestéatomes opérés de l'oreille moyenne. Les récidives de cholestéatome sont fréquentes et les oreilles opérées sont parfois difficiles à analyser en TDM en cas de comblement de la cavité opératoire. Des séquences IRM spécifiques sont alors nécessaires pour différencier une récidive de cholestéatome, du tissu fibro-inflammatoire fréquemment présent. Plusieurs auteurs avaient montré l'intérêt des séquences de diffusion du fait de coefficients de diffusion très différents entre le tissu fibro-inflammatoire et le cholestéatome. Cependant ces premières séquences de diffusion EPI basse résolution, étaient peu adaptées au rocher et la base du crâne. Notre travail a été de mettre au point et de développer une séquence de diffusion HR Turbo Spin écho adaptée à l'oreille et à la base du crâne permettant le dépistage des récidives de cholestéatome et de valider cette séquence par comparaison au gadolinium tardif et à la chirurgie. Mon travail sur la base du crâne haute résolution m'a également permis de développer des séquences Spin Echo T1 et 3D Echo de gradient T1 en Haute Résolution avec saturation de la graisse permettant une analyse fine des extensions tumorales périnerveuses à la base du crâne principalement dans les cancers du nasopharynx. Ces travaux ont permis de définir les voies d'extension précises de ces tumeurs afin de ne pas sous-évaluer le stade initial de ces tumeurs dans la classification TNM de l'UICC. Ces travaux associés à ceux d'autres chercheurs ont permis de mettre à jour récemment cette classification UICC des tumeurs du nasopharynx. Une de mes principales voies de recherche a été le dépistage, l'analyse et la description des pathologies de l’oreille interne. Une étude longitudinale menée de 1998 à 2008 incluant toutes les pathologies intra-labyrinthiques découvertes au CHU de Lille, a permis de définir et de caractériser trois grands types de pathologies distinctes: les schwannomes intra-labyrinthiques, les labyrinthites, les hémorragies intra-labyrinthiques. Ces pathologies nécessitent des prises en charge différentes. Nous avons pu également définir des critères pronostics en particulier des critères de gravité nécessitant une prise en charge rapide adaptée. Dans le cadre ce travail de recherche sur les pathologies de l’oreille interne, nous nous sommes également intéressés au Syndrome de déhiscence du canal semi-circulaire supérieur, syndrome clinique récemment décrit par Minor en 1998. [...] / Since the beginning of the 1990s, the imaging of the ear and skull base has grown considerably. Recently, poorly known pathologies have been investigated by imaging, in particular with MRI. The objective of my research works was to develop high resolution (HR) sequences dedicated to the ear and the skull base, allowing a fine semiological analysis and a characterization of these various pathologies. The purpose is to contribute to a more appropriate medical management. The beginning of my work was directed towards the internal auditory canal. My initial purpose was to determine and develop a three-dimensional HR T2 sequence for the inner ear and the internal auditory canal as well as a spin echo T1 HR with thin slices. These sequences allowed the precise analysis of the extension of vestibular schwannomas in the fundus of the internal auditory canal. This study has indentified a relevant criteria for the therapeutic choice (surgery versus radiosurgery) and for the choice of the surgical approach. My work has also aimed to the development of diffusion sequences dedicated to the skull base. The purpose was to develop a HR diffusion sequences in the follow-up of operated cholesteatoma of the middle ear. Recurrence of cholesteatoma is frequent and the operated ears are sometimes difficult to analyze on CT, particularly when the postoperative cavity is completely filled. Specific MRI sequences are then necessary to differentiate a recurrent cholesteatoma from fibro-inflammatory tissue. The fact that the diffusion coefficient between fibro-inflammatory tissue and cholesteatoma is different has been shown by several authors. However these early sequences of echoplanar imaging (EPI) diffusion with low resolution were poorly suited to the temporal bone and the skull base. Our work was to finalize and develop a sequence of turbo spin echo HR diffusion, adapted to the ear and skull base for the screening of recurrent cholesteatoma and validate this sequence by comparison with delayed post gadolinium spin echo T1 sequence and surgery. My work on the HR imaging of the skull base also enabled me to develop some other sequences: spin echo T1 and 3D HR gradient echo T1 with fat saturation allowing for the detailed analysis of perineural spread to the skull base, mainly in nasopharyngeal cancers. This work helped to define the precise pathways of extension of these tumours in order not to underestimate the initial stage of these tumours in the TNM UICC classification. This work together with those of other researchers allowed the recent update of the UICC classification in nasopharyngeal tumours. One of my main research topics has been the screening, analysis and description of the pathologies of the inner ear. A longitudinal study from 1998 to 2008, including all the intralabyrinthine pathologies discovered to the University Center of Lille, allowed to define and characterize three major different pathologies: intralabyrinthine schwannoma, labyrinthitis and intralabyrinthine hemorrhage. These pathologies require different treatments. We were also able to define prognostic criteria in particular criteria of severity requiring a rapid and adapted medical management. Within the framework of my research on the pathologies of the inner ear, we were also interested in the syndrome of dehiscence of the superior semicircular canal. This clinical syndrome was recently described by Minor in 1998. A retrospective study of the cases discovered between 2007 and 2009, included a HR TDM of the temporal bone and a HR MRI (in particular imaging fusion between the 3D HR time-of-flight (TOF) and the 3D HR T2 sequences), enabled to identify a variant of the classic form of dehiscence. [...]

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