RESUMO
Radiological aspects of middle ear malformations based on the study of 31 observations should be correlated with the modalities of normal and abnormal morphogenesis. This is particularly the case for malformations of the ossicles, which can be classified according their precise branchial origin. Facial nerve malformations, dysgenesis of the footplate and atresia of the external auditory meatus is discussed in relation to normal events of middle ear morphogenesis. Standard histochemical procedures and study of radioactive sulphur uptake in the mouse embryo permit to characterize some factors of middle ear ossicles formation. Study of correlations between radiological features and experimental results reveal that the important factors are: the chronology of morphogenesis; the organization of branchial structures; the patterns of neural crest cells migration; the influence of environmental factors. Furthermore, teratologic features obtained in animals models can be correlated with human syndromes.
