Vermian multinodular and vacuolating lesion of unknown significance discovered following syncope: a case report.

Introduction and importance: Multinodular and Vacuolating Posterior Fossa Lesions of Unknown Significance (MV PLUS) are benign cystic lesions that, though typically asymptomatic, can present with neurological symptoms such as seizures, headaches, and syncope. These lesions are predominantly found in sub-tentorial brain structures but can also appear in supratentorial areas. MRI is crucial in detecting these lesions, characterized by small nodules with high intensity on T2-FLAIR sequences. Despite increasing awareness, the pathophysiology and classification of MV PLUS lesions remain unclear, necessitating further research and careful monitoring. Case presentation: A 52-year-old female presented with subjective dizziness and a recent syncope episode. Neurological examination showed ataxia and a positive Romberg sign. MRI revealed a multicystic and nodular lesion in the vermian and paravermian regions, with altered signal intensity on T1-weighted and FLAIR sequences. The lesion showed no pathological enhancement post-gadolinium administration, and spectroscopy revealed no significant metabolite peaks. Clinical improvement was observed following corticosteroid and antivertiginous therapy, and the patient was discharged with a recommendation for neuroradiological follow-up. Clinical discussion: MV PLUS lesions are a subset of multinodular and vacuolating lesions that present significant diagnostic challenges due to their complex radiological features. First described in 2013, these lesions have distinct MRI characteristics, including a nodular appearance with high T2-FLAIR intensity and occasional cystic components. Despite being benign and typically stable, the differential diagnosis includes various other intracranial lesions, requiring careful evaluation. The pathogenesis and optimal management strategies for MV PLUS lesions are still under investigation, emphasizing the need for continued research. Conclusion: MV PLUS lesions, although rare and benign, present unique diagnostic challenges due to their varied radiological features and potential neurological symptoms. Regular MRI monitoring is essential to track their stability, given the current lack of understanding regarding their pathophysiology and long-term implications. Further research is needed to elucidate the etiology, natural history, and optimal management of these intriguing lesions.