The following sequences are available:

T2 weighted transverse, T2* weighted transverse, T1 weighted transverse pre and post contrast medium administration, FLAIR dorsal

A focal, approx. 0.5cm large, intraaxial lesion is present in the grey matter of the suprasylvian gyrus of the right temporal lobe. Centrally the lesion is hypointense on T1w, T2w and FLAIR images. Peripherally a thin, hypointense rim is visible. On the T2* weighted images a large signal void due to a susceptibility artefact is present.

There are no signs of a mass effect. No significant contrast medium uptake is present.

• Focal, intraaxial cortical lesion right suprasylvian gyrus with suceptibility artifact

The suceptibility artefact is indicative for the presence of haemorrhage.

The most common cause for primary intraaxial bleeding is an amyloidangiopathy. Amyloidangiopathy represents perivascular accumulation of hemosiderin and generally appears as multiple very small, pin point changes. Another cause for primary intraaxial bleeding is a spontaneous rupture of vessels due to systemic hypertension, e.g in case of chronic renal disease.

Most common cause for secondary bleeding into the brain parenchyma is an infection with angiostrongylus vasorum. Further differential diagnoses for secondary bleeding include coagulopathies, such as occur with Cushing’s disease, trauma associated bleeding, tumour associated bleeding (vascular neoplasia, e.g. hemangioendothelioma, primary CNS neoplasia, metastases) or vascular malformations.

Haemorrhagic infarcts in dogs are rare, compared to humans.

Owing to the fact that in this case a single lesion with a relatively large susceptibility artefact is present, bleeding secondary to an infection with Angiostrongylus vasorum is considered the most likely diagnosis.

Furth differential diagnoses include systemic hypertension and coagulopathy. Vascular neoplasia and malformations are rare and therefore considered less likely but cannot be ruled out completely.

Due to the lack of contrast enhancement and the absence of peripheral oedema a brain metastasis is unlikely. Trauma associated bleeding can be excluded as no trauma was reported in the history and there are no changes in the overlying musculature which indicate previous trauma.

Fecal examination proved a severe infection with Angiostrongylus vasorum.

The dog was dewormed.

Under therapy with anticonvulsant drugs seizuring was reduced and eventually ceased.