Multinodular and Vacuolating Posterior Fossa Lesions of Unknown Significance. Case Report in Colombia

Abstract

There are multiple types of cystic lesions that can be found in the brain and in the posterior fossa. Among these, a new entity called MV PLUS (Multinodular and Vacuolating Posterior Fossa Lesions of Unknown Significance) has similar imaging characteristics to the vacuolating multinodular tumor, but as indicated by its acronym in English, it is located in the posterior fossa. These tumors are defined as a group of small, high intensity nodular subcortical images in the T2-FLAIR, with or without post-contrast enhancement. They can be differentiated from other cystic entities, because they are clustered lesions, without reactive inflammatory changes, in a cortex of normal appearance and without changes at follow-up. The latter, causes them to be considered benign, non-aggressive lesions. We present the case of a 21-year-old patient, who presented an incidentally found lesion in the central region of the vermis. MRI showed a multicystic-looking mass, that had no changes at follow-up in the last 3 years and without obvious differential diagnosis, suggestive of MV PLUS.