Malignant Melanoma of the Brainstem: A Unicorn Not a Popcorn.

BACKGROUND

Primary intracranial malignant melanomas (PIMMs) are uncommon lesions of the central nervous system. Brainstem involvement is of rare occurrence.

METHODS AND MATERIAL: A 33-year-old male presented with the chief complaints of progressively increasing headache, visual disturbances, and diplopia from the last 6 months. Magnetic resonance imaging (MRI) showed a well-defined lesion in the midbrain appearing heterogeneously hyperintense on T1WI and containing mixed hyperintense and hypointense areas on T2WI. Multiple areas of SWI blooming, suggestive of hemorrhage, were seen within the lesion.

CONCLUSION

Brainstem malignant melanoma can masquerade cavernoma as seen in our case. Therefore, malignant melanomas should be considered in the differential diagnosis of brainstem lesions that presents with bleed.