Multiple episodes of hemorrhage on MR

At tonight’s KCC, we saw some great cases from the clinic this week. One of them was a 7 year old MN Vizsla with a history of inappetance, ataxia and fever. He had an MR performed, which showed multifocal areas of abnormality. There were lesions in the right cerebrum, left frontal lobe, and left cerebellum. All of the lesions had a component of hyperintensity on T1 and T2 weighted images. They were intra-axial, and the largest one in the cerebellum had both hyperintense and hypointense components. The large lesion was causing a mass effect with displacement of the brainstem and midline shift.

The cerebellar lesion showed rim enhancement with gadolinium, and had an “onionskin” appearance on T2 and Flair images. There was also edema surrounding this lesion on both sequences.

Differential diagnoses for an asymmetric, multifocal disease included metastatic neoplasia, infarction, granulomatous disease, or septic emboli such as in endocarditis. There was a definite hemorrhagic component because of the hyperintensity on T1 and T2 images.

The interesting point that came out was that the “onionskin” appearance usually means multiple episodes of hemorrhage have occured at different times. The intensity of the blood changes over time as it is transformed to different metabolites.

This animal had disseminated hemangiosarcoma, including the right atrium, lung and multiple abdominal organs.