, Tout d'abord, on localise la lésion : elle est rétrobulbaire, principalement intraconique avec une part extraconique
, Le globe est lui-aussi moulé par cette masse, qui est, par ailleurs
, On va donc s'intéresser au signal de la lésion. Elle est en hyposignal T1, signal intermédiaire T2 et se
, On se retrouve donc devant un signal cellulaire. La dernière étape est de rechercher des critères de malignité. L'ADC a des valeurs très basses indiquant une lésion très cellulaire. De plus, l'analyse de la courbe d'évolution du signal est de type plateau. La combinaison de ces 2 critères, associée à la morphologie de la lésion (se moulant sur les structures adjacentes)
, En diffusion, il existait un coefficient d'ADC de 1,33 x 10 -3 mm 2 /s, donc plutôt en faveur d'une lésion bénigne. La courbe d'intensité, quant à elle, montrait un profil type plateau, donc ne permettant pas de statuer sur une lésion bénigne ou maligne. D'après les éléments, cette lésion était plutôt en faveur d'une pathologie lymphoproliférative et l'ADC nous oriente vers le caractère peu cellulaire de cette lésion, c'est-à-dire rechercher les critères en faveur de la malignité
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